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1.  Florbetapir PET analysis of amyloid-β deposition in the presenilin 1 E280A autosomal dominant Alzheimer’s disease kindred: a cross-sectional study 
Lancet neurology  2012;11(12):10.1016/S1474-4422(12)70227-2.
Fibrillar amyloid-β (Aβ) is thought to begin accumulating in the brain many years before the onset of clinical impairment in patients with Alzheimer’s disease. By assessing the accumulation of Aβ in people at risk of genetic forms of Alzheimer’s disease, we can identify how early preclinical changes start in individuals certain to develop dementia later in life. We sought to characterise the age-related accumulation of Aβ deposition in presenilin 1 (PSEN1) E280A mutation carriers across the spectrum of preclinical disease.
Between Aug 1 and Dec 6, 2011, members of the familial Alzheimer’s disease Colombian kindred aged 18–60 years were recruited from the Alzheimer’s Prevention Initiative’s registry at the University of Antioquia, Medellín, Colombia. Cross-sectional assessment using florbetapir PET was done in symptomatic mutation carriers with mild cognitive impairment or mild dementia, asymptomatic carriers, and asymptomatic non-carriers. These assessments were done at the Banner Alzheimer’s Institute in Phoenix, AZ, USA. A cortical grey matter mask consisting of six predefined regions. was used to measure mean cortical florbetapir PET binding. Cortical-to-pontine standard-uptake value ratios were used to characterise the cross-sectional accumulation of fibrillar Aβ deposition in carriers and non-carriers with regression analysis and to estimate the trajectories of fibrillar Aβ deposition.
We enrolled a cohort of 11 symptomatic individuals, 19 presymptomatic mutation carriers, and 20 asymptomatic non-carriers, ranging in age from 20 to 56 years. There was greater florbetapir binding in asymptomatic PSEN1 E280A mutation carriers than in age matched non-carriers. Fibrillar Aβ began to accumulate in PSEN 1E280A mutation carriers at a mean age of 28·2 years (95% CI 27·3–33·4), about 16 years and 21 years before the predicted median ages at mild cognitive impairment and dementia onset, respectively. 18F florbetapir binding rose steeply over the next 9·4 years and plateaued at a mean age of 37·6 years (95% CI 35·3–40·2), about 6 and 11 years before the expected respective median ages at mild cognitive impairment and dementia onset. Prominent florbetapir binding was seen in the anterior and posterior cingulate, precuneus, and parietotemporal and frontal grey matter, as well as in the basal ganglia. Binding in the basal ganglia was not seen earlier or more prominently than in other regions.
These findings contribute to the understanding of preclinical familial Alzheimer’s disease and help set the stage for assessment of amyloid-modifying treatments in the prevention of familial Alzheimer’s disease.
Avid Radiopharmaceuticals, Banner Alzheimer’s Foundation, Nomis Foundation, Anonymous Foundation, Forget Me Not Initiative, Colciencias, National Institute on Aging, and the State of Arizona.
PMCID: PMC3515078  PMID: 23137949
The Lancet. Neurology  2012;11(12):1048-1056.
We previously detected functional brain imaging abnormalities in young adults at genetic risk for late-onset Alzheimer’s disease (AD). Here, we sought to characterize structural and functional magnetic resonance imaging (MRI), cerebrospinal fluid (CSF), and plasma biomarker abnormalities in young adults at risk for autosomal dominant early-onset AD. Biomarker measurements were characterized and compared in presenilin 1 (PSEN1) E280A mutation carriers and non-carriers from the world’s largest known autosomal dominant early-onset AD kindred, more than two decades before the carriers’ estimated median age of 44 at the onset of mild cognitive impairment (MCI) and before their estimated age of 28 at the onset of amyloid-β (Aβ) plaque deposition.
Biomarker data for this cross-sectional study were acquired in Antioquia, Colombia between July and August, 2010. Forty-four participants from the Colombian Alzheimer’s Prevention Initiative (API) Registry had structural MRIs, functional MRIs during associative memory encoding/novel viewing and control tasks, and cognitive assessments. They included 20 mutation carriers and 24 non-carriers, who were cognitively normal, 18-26 years old and matched for their gender, age, and educational level. Twenty of the participants, including 10 mutation carriers and 10 non-carriers, had lumbar punctures and venipunctures. Primary outcome measures included task-dependent hippocampal/parahippocampal activations and precuneus/posterior cingulate deactivations, regional gray matter reductions, CSF Aβ1-42, total tau and phospho-tau181 levels, and plasma Aβ1-42 levels and Aβ1-42/Aβ1-40 ratios. Structural and functional MRI data were compared using automated brain mapping algorithms and AD-related search regions. Cognitive and fluid biomarkers were compared using Mann-Whitney tests.
The mutation carrier and non-carrier groups did not differ significantly in their dementia ratings, neuropsychological test scores, or proportion of apolipoprotein E (APOE) ε4 carriers. Compared to the non-carriers, carriers had higher CSF Aβ1-42 levels (p=0·008), plasma Aβ1-42 levels (p=0·01), and plasma Aβ1-42/Aβ1-40 ratios (p=0·001), consistent with Aβ1-42 overproduction. They also had greater hippocampal/parahippocampal activations (as low as p=0·008, after correction for multiple comparisons), less precuneus/posterior cingulate deactivations (as low as p=0·001, after correction), less gray matter in several regions (p-values <0·005, uncorrected, and corrected p=0·008 in the parietal search region), similar to findings in the later preclinical and clinical stages of autosomal dominant and late-onset AD.
Young adults at genetic risk for autosomal dominant AD have functional and structural MRI abnormalities, along with CSF and plasma biomarker findings consistent with Aβ1-42 over-production. While the extent to which the underlying brain changes are progressive or developmental remain to be determined, this study demonstrates the earliest known biomarker changes in cognitively normal people at genetic risk for autosomal dominant AD.
Banner Alzheimer’s Foundation, Nomis Foundation, Anonymous Foundation, Forget Me Not Initiative, Boston University Department of Psychology, Colciencias (1115-408-20512, 1115-545-31651), National Institute on Aging (R01 AG031581, P30 AG19610, UO1 AG024904, RO1 AG025526, RF1AG041705), National Institute of Neurological Disorders and Stroke (F31-NS078786) and state of Arizona.
PMCID: PMC4181671  PMID: 23137948
Alzheimer’s disease; biomarkers; preclinical; early-onset; dominantly inherited; MRI; functional MRI; cerebrospinal fluid; plasma; presenilin E280A mutation; amyloid; tau; genetics; prevention
3.  Psychosocial Factors That Shape Patient and Carer Experiences of Dementia Diagnosis and Treatment: A Systematic Review of Qualitative Studies 
PLoS Medicine  2012;9(10):e1001331.
A systematic review of qualitative studies conducted by Frances Bunn and colleagues identifies and describes the experiences of patients and caregivers on receiving and adapting to a diagnosis of dementia.
Early diagnosis and intervention for people with dementia is increasingly considered a priority, but practitioners are concerned with the effects of earlier diagnosis and interventions on patients and caregivers. This systematic review evaluates the qualitative evidence about how people accommodate and adapt to the diagnosis of dementia and its immediate consequences, to guide practice.
Methods and Findings
We systematically reviewed qualitative studies exploring experiences of community-dwelling individuals with dementia, and their carers, around diagnosis and the transition to becoming a person with dementia. We searched PubMed, PsychINFO, Embase, CINAHL, and the British Nursing Index (all searched in May 2010 with no date restrictions; PubMed search updated in February 2012), checked reference lists, and undertook citation searches in PubMed and Google Scholar (ongoing to September 2011). We used thematic synthesis to identify key themes, commonalities, barriers to earlier diagnosis, and support identified as helpful. We identified 126 papers reporting 102 studies including a total of 3,095 participants. Three overarching themes emerged from our analysis: (1) pathways through diagnosis, including its impact on identity, roles, and relationships; (2) resolving conflicts to accommodate a diagnosis, including the acceptability of support, focusing on the present or the future, and the use or avoidance of knowledge; and (3) strategies and support to minimise the impact of dementia. Consistent barriers to diagnosis include stigma, normalisation of symptoms, and lack of knowledge. Studies report a lack of specialist support particularly post-diagnosis.
There is an extensive body of qualitative literature on the experiences of community-dwelling individuals with dementia on receiving and adapting to a diagnosis of dementia. We present a thematic analysis that could be useful to professionals working with people with dementia. We suggest that research emphasis should shift towards the development and evaluation of interventions, particularly those providing support after diagnosis.
Please see later in the article for the Editors' Summary.
Editors' Summary
Dementia is a decline in mental ability severe enough to interfere with daily life. Alzheimer disease is the most common type of dementia. People with dementia usually have problems with two or more cognitive functions—thinking, language, memory, understanding, and judgment. Dementia is rare before the age of 65, but about a quarter of people over 85 have dementia. Because more people live longer these days, the number of patients with dementia is increasing. It is estimated that today between 40 and 50 million people live with dementia worldwide. By 2050, this number is expected to triple.
One way to study what dementia means to patients and their carers (most often spouses or other family members) is through qualitative research. Qualitative research aims to develop an in-depth understanding of individuals' experiences and behavior, as well as the reasons for their feelings and actions. In qualitative studies, researchers interview patients, their families, and doctors. When the studies are published, they usually contain direct quotations from interviews as well as summaries by the scientists who designed the interviews and analyzed the responses.
Why Was This Study Done?
This study was done to better understand the experiences and attitudes of patients and their carers surrounding dementia diagnosis. It focused on patients who lived and were cared for within the community (as opposed to people living in senior care facilities or other institutions). Most cases of dementia are progressive, meaning symptoms get worse over time. Diagnosis often happens at an advanced stage of the disease, and some patients never receive a formal diagnosis. This could have many possible reasons, including unawareness or denial of symptoms by patients and people close to them. The study was also trying to understand barriers to early diagnosis and what type of support is useful for newly diagnosed patients and carers.
What Did the Researchers Do and Find?
The researchers conducted a systematic search for published qualitative research studies that reported on the experience, beliefs, feelings, and attitudes surrounding dementia diagnosis. They identified and reviewed 102 such studies. Among the quotations and summaries of the individual studies, they looked for prominent and recurring themes. They also compared and contrasted the respective experiences of patients and carers.
Overall, they found that the complexity and variety of responses to a diagnosis of dementia means that making the diagnosis and conveying it to patients and carers is challenging. Negative connotations associated with dementia, inconsistent symptoms, and not knowing enough about the signs and symptoms were commonly reported barriers to early dementia diagnosis. It was often the carer who initiated the search for help from a doctor, and among patients, willingness and readiness to receive a diagnosis varied. Being told one had dementia had a big impact on a patient's identity and often caused feelings of loss, anger, fear, and frustration. Spouses had to adjust to increasingly unequal relationships and the transition to a role as carer. The strain associated with this often caused health problems in the carers as well. On the other hand, studies examining the experience of couples often reported that they found ways to continue working together as a team.
Adjusting to a dementia diagnosis is a complex process. Initially, most patients and carers experienced conflicts, for example, between autonomy and safety, between recognizing the need for help but reluctance to accept it, or between living in the present and dealing with anxiety about and preparing for the future. As these were resolved and as the disease progressed, the attitudes of patients and carers towards dementia often became more balanced and accepting. Many patients and their families adopted strategies to cope with the impact of dementia on their lives in order to manage the disease and maintain some sort of normal life. These included practical strategies involving reminders, social strategies such as relying on family support, and emotional strategies such as using humor. At some point many patients and carers reported that they were able to adopt positive mindsets and incorporate dementia in their lives.
The studies also pointed to an urgent need for support from outside the family, both right after diagnosis and subsequently. General practitioners and family physicians have important roles in helping patients and carers to get access to information, social and psychological support, and community care. The need for information was reported to be ongoing and varied, and meeting it required a variety of sources and formats. Key needs for patients and carers mentioned in the studies include information on financial aids and entitlements early on, and continued access to supportive professionals and specialists.
What Do These Findings Mean?
Qualitative studies to date on how patients and carers respond to a diagnosis of dementia provide a fairly detailed picture of their experiences. The summary provided here should help professionals to understand better the challenges patients and carers face around the time of diagnosis as well as their immediate and evolving needs. The results also suggest that future research should focus on the development and evaluation of ways to meet those needs.
Additional Information
Please access these websites via the online version of this summary at
Wikipedia has pages on dementia and qualitative research (note that Wikipedia is a free online encyclopedia that anyone can edit)
Alzheimer Europe, an umbrella organization of 34 Alzheimer associations from 30 countries across Europe, has a page on the different approaches to research
The UK Department of Health has pages on dementia, including guidelines for carers of people with dementia
MedlinePlus also has information about dementia
PMCID: PMC3484131  PMID: 23118618
4.  Alzheimer’s disease phenotypes and genotypes associated with mutations in presenilin 2 
Brain  2010;133(4):1143-1154.
Mutations in presenilin 2 are rare causes of early onset familial Alzheimer’s disease. Eighteen presenilin 2 mutations have been reported, although not all have been confirmed pathogenic. Much remains to be learned about the range of phenotypes associated with these mutations. We have analysed our unique collection of 146 affected cases in 11 Volga German families, 101 who are likely to have the same N141I mutation in presenilin 2 (54 genotyped confirmed). We have also assessed the detailed neuropathologic findings in 18 autopsies from these families and reviewed the world’s literature on other presenilin 2 mutations; presenting a novel mutation that is predicted to lead to a premature truncation codon. Seven presenilin 2 mutations reported in the literature have strong evidence for pathogenicity whereas others may be benign polymorphisms. One hundred and one affected persons, with sufficient historical information from the Volga German pedigrees (N141I mutation), had a mean onset age of 53.7 years ± 7.8 (range 39–75) and mean age at death of 64.2 years ± 9.8 (range 43–88). These figures overlap with and generally fall between the results from the subjects in our centre who have late onset familial Alzheimer’s disease or mutations in presenilin 1. Seizures were noted in 20 (30%) of 64 subjects with detailed medical records. Two mutation carriers lived beyond age 80 without developing dementia, representing uncommon examples of decreased penetrance. Two persons had severe amyloid angiopathy and haemorrhagic stroke. Eighteen cases had detailed histopathology available and analysed at our institution. Braak stage was five or six, amyloid angiopathy and neuritic plaques were common and more than 75% had Lewy bodies in the amygdala. TAR DNA-binding protein-43 inclusions were uncommon. In addition, a 58-year-old female with a 2 year course of cognitive decline and no family history of dementia has abnormal fludeoxyglucose-positron emission tomography imaging and a novel 2 base pair deletion in presenilin 2 at nucleotide 342/343, predicted to produce a frame-shift and premature termination. We conclude that mutations in presenilin 2 are rare with only seven being well documented in the literature. The best studied N141I mutation produces an Alzheimer’s disease phenotype with a wide range of onset ages overlapping both early and late onset Alzheimer’s disease, often associated with seizures, high penetrance and typical Alzheimer’s disease neuropathology. A novel premature termination mutation supports loss of function or haploinsufficiency as pathogenic mechanisms in presenilin 2 associated Alzheimer’s disease.
PMCID: PMC2850581  PMID: 20375137
Alzheimer’s disease; presenilin 2; human genetics; dementia; amyloid; Volga German
5.  Familial Alzheimer’s disease–associated presenilin-1 alters cerebellar activity and calcium homeostasis 
The Journal of Clinical Investigation  2014;124(4):1552-1567.
Familial Alzheimer’s disease (FAD) is characterized by autosomal dominant heritability and early disease onset. Mutations in the gene encoding presenilin-1 (PS1) are found in approximately 80% of cases of FAD, with some of these patients presenting cerebellar damage with amyloid plaques and ataxia with unclear pathophysiology. A Colombian kindred carrying the PS1-E280A mutation is the largest known cohort of PS1-FAD patients. Here, we investigated PS1-E280A–associated cerebellar dysfunction and found that it occurs early in PS1-E208A carriers, while cerebellar signs are highly prevalent in patients with dementia. Postmortem analysis of cerebella of PS1-E280A carrier revealed greater Purkinje cell (PC) loss and more abnormal mitochondria compared with controls. In PS1-E280A tissue, ER/mitochondria tethering was impaired, Ca2+ channels IP3Rs and CACNA1A were downregulated, and Ca2+-dependent mitochondrial transport proteins MIRO1 and KIF5C were reduced. Accordingly, expression of PS1-E280A in a neuronal cell line altered ER/mitochondria tethering and transport compared with that in cells expressing wild-type PS1. In a murine model of PS1-FAD, animals exhibited mild ataxia and reduced PC simple spike activity prior to cerebellar β-amyloid deposition. Our data suggest that impaired calcium homeostasis and mitochondrial dysfunction in PS1-FAD PCs reduces their activity and contributes to motor coordination deficits prior to Aβ aggregation and dementia. We propose that PS1-E280A affects both Ca2+ homeostasis and Aβ precursor processing, leading to FAD and neurodegeneration.
PMCID: PMC3973081  PMID: 24569455
6.  Cholinesterase Inhibitors in Mild Cognitive Impairment: A Systematic Review of Randomised Trials 
PLoS Medicine  2007;4(11):e338.
Mild cognitive impairment (MCI) refers to a transitional zone between normal ageing and dementia. Despite the uncertainty regarding the definition of MCI as a clinical entity, clinical trials have been conducted in the attempt to study the role of cholinesterase inhibitors (ChEIs) currently approved for symptomatic treatment of mild to moderate Alzheimer disease (AD), in preventing progression from MCI to AD. The objective of this review is to assess the effects of ChEIs (donepezil, rivastigmine, and galantamine) in delaying the conversion from MCI to Alzheimer disease or dementia.
Methods and Findings
The terms “donepezil”, “rivastigmine”, “galantamine”, and “mild cognitive impairment” and their variants, synonyms, and acronyms were used as search terms in four electronic databases (MEDLINE, EMBASE, Cochrane, PsycINFO) and three registers: the Cochrane Collaboration Trial Register, Current Controlled Trials, and Published and unpublished studies were included if they were randomized clinical trials published (or described) in English and conducted among persons who had received a diagnosis of MCI and/or abnormal memory function documented by a neuropsychological assessment. A standardized data extraction form was used. The reporting quality was assessed using the Jadad scale. Three published and five unpublished trials met the inclusion criteria (three on donepezil, two on rivastigmine, and three on galantamine). Enrolment criteria differed among the trials, so the study populations were not homogeneous. The duration of the trials ranged from 24 wk to 3 y. No significant differences emerged in the probability of conversion from MCI to AD or dementia between the treated groups and the placebo groups. The rate of conversion ranged from 13% (over 2 y) to 25% (over 3 y) among treated patients, and from 18% (over 2 y) to 28% (over 3 y) among those in the placebo groups. Only for two studies was it possible to derive point estimates of the relative risk of conversion: 0.85 (95% confidence interval 0.64–1.12), and 0.84 (0.57–1.25). Statistically significant differences emerged for three secondary end points. However, when adjusting for multiple comparisons, only one difference remained significant (i.e., the rate of atrophy in the whole brain).
The use of ChEIs in MCI was not associated with any delay in the onset of AD or dementia. Moreover, the safety profile showed that the risks associated with ChEIs are not negligible. The uncertainty regarding MCI as a clinical entity raises the question as to the scientific validity of these trials.
A systematic review of trials of cholinesterase inhibitors for preventing transition of mild cognitive impairment (MCI) to dementia, conducted by Roberto Raschetti and colleagues, found no difference between treatment and control groups and concluded that uncertainty regarding the definition of MCI casts doubts on the validity of such trials.
Editors' Summary
Worldwide, more than 24 million people have dementia, a group of brain disorders characterized by an irreversible decline in memory, problem solving, communication, and other “cognitive” functions. The commonest form of dementia is Alzheimer disease (AD). The risk of developing AD increases with age—AD is rare in people younger than 65 but about half of people over 85 years old have it. The earliest symptom of AD is usually difficulty in remembering new information. As the disease progresses, patients may become confused and have problems expressing themselves. Their behavior and personality can also change. In advanced AD, patients need help with daily activities like dressing and eating, and eventually lose their ability to recognize relatives and to communicate. There is no cure for AD but a class of drugs called “cholinesterase inhibitors” can sometimes temporarily slow the worsening of symptoms. Three cholinesterase inhibitors—donepezil, rivastigmine, and galantamine—are currently approved for use in mild-to-moderate AD.
Why Was This Study Done?
Some experts have questioned the efficacy of cholinesterase inhibitors in AD, but other experts and patient support groups have called for these drugs to be given to patients with a condition called mild cognitive impairment (MCI) as well as to those with mild AD. People with MCI have memory problems that are more severe than those normally seen in people of their age but no other symptoms of dementia. They are thought to have an increased risk of developing AD, but it is not known whether everyone with MCI eventually develops AD, and there is no standardized way to diagnose MCI. Despite these uncertainties, several clinical trials have investigated whether cholinesterase inhibitors prevent progression from MCI to AD. In this study, the researchers have assessed whether the results of these trials provide any evidence that cholinesterase inhibitors can prevent MCI progressing to AD.
What Did the Researchers Do and Find?
The researchers conducted a systematic review of the medical literature to find trials that had addressed this issue, which met criteria that they had defined clearly in advance of their search. They identified three published and five unpublished randomized controlled trials (studies in which patients randomly receive the test drug or an inactive placebo) that investigated the effect of cholinesterase inhibitors on the progression of MCI. The researchers obtained the results of six of these trials—four examined the effect of cholinesterase inhibitors on the conversion of MCI to clinically diagnosed AD or dementia (the primary end point); all six examined the effect of the drugs on several secondary end points (for example, individual aspects of cognitive function). None of the drugs produced a statistically significant difference (a difference that is unlikely to have happened by chance) in the probability of progression from MCI to AD. The only statistically significant secondary end point after adjustment for multiple comparisons (when many outcomes are considered, false positive results can occur unless specific mathematical techniques are used to prevent this problem) was a decrease in the rate of brain shrinkage associated with galantamine treatment. More patients treated with cholinesterase inhibitors dropped out of trials because of adverse effects than patients given placebo. Finally, in the one trial that reported all causes of deaths, one participant who received placebo and six who received galantamine died.
What Do These Findings Mean?
These findings suggest that the use of cholinesterase inhibitors is not associated with any delay in the onset of clinically diagnosed AD or dementia in people with MCI. They also show that the use of these drugs has no effect on most surrogate (substitute) indicators of AD but that the risks associated with their use are not negligible. However, because MCI has not yet been clearly defined as a clinical condition that precedes dementia, some (even many) of the patients enrolled into the trials that the researchers assessed may not actually have had MCI. Thus, further clinical trials are needed to clarify whether cholinesterase inhibitors can delay the progression of MCI to dementia, but these additional trials should not be done until the diagnosis of MCI has been standardized.
Additional Information.
Please access these Web sites via the online version of this summary at
An essay by Matthews and colleagues, in the October 2007 issue of PLoS Medicine, discusses how mild cognitive impairment is currently diagnosed
The US Alzheimer's Association provides information about all aspects of Alzheimer disease, including fact sheets on treatments for Alzheimer disease and on mild cognitive impairment
The UK Alzheimer's Society provides information for patients and caregivers on all aspects of dementia, including drug treatments and mild cognitive impairment
The UK charity DIPEx provides short video clips of personal experiences of care givers of people with dementia
PMCID: PMC2082649  PMID: 18044984
7.  Cortical atrophy in presymptomatic Alzheimer’s disease presenilin 1 mutation carriers 
Sporadic late-onset Alzheimer’s disease (AD) dementia has been associated with a ‘signature’ of cortical atrophy in paralimbic and heteromodal association regions measured with MRI.
To investigate whether a similar pattern of cortical atrophy is present in presymptomatic presenilin 1 E280A mutation carriers an average of 6 years before clinical symptom onset.
40 cognitively normal volunteers from a Colombian population with familial AD were included; 18 were positive for the AD-associated presenilin 1 mutation (carriers, mean age=38) whereas 22 were non-carriers. T1-weighted volumetric MRI images were acquired and cortical thickness was measured. A priori regions of interest from our previous work were used to obtain thickness from AD-signature regions.
Compared to non-carriers, presymptomatic presenilin 1 mutation carriers exhibited thinner cortex within the AD-signature summary measure (p<0.008). Analyses of individual regions demonstrated thinner angular gyrus, precuneus and superior parietal lobule in carriers compared to non-carriers, with trend-level effects in the medial temporal lobe.
Results demonstrate that cognitively normal individuals genetically determined to develop AD have a thinner cerebral cortex than non-carriers in regions known to be affected by typical late-onset sporadic AD. These findings provide further support for the hypothesis that cortical atrophy is present in preclinical AD more than 5 years prior to symptom onset. Further research is needed to determine whether this method could be used to characterise the age-dependent trajectory of cortical atrophy in presymptomatic stages of AD.
PMCID: PMC3632663  PMID: 23134660
8.  Prevalence, Distribution, and Impact of Mild Cognitive Impairment in Latin America, China, and India: A 10/66 Population-Based Study 
PLoS Medicine  2012;9(2):e1001170.
A set of cross-sectional surveys carried out in Cuba, Dominican Republic, Peru, Mexico, Venezuela, Puerto Rico, China, and India reveal the prevalence and between-country variation in mild cognitive impairment at a population level.
Rapid demographic ageing is a growing public health issue in many low- and middle-income countries (LAMICs). Mild cognitive impairment (MCI) is a construct frequently used to define groups of people who may be at risk of developing dementia, crucial for targeting preventative interventions. However, little is known about the prevalence or impact of MCI in LAMIC settings.
Methods and Findings
Data were analysed from cross-sectional surveys established by the 10/66 Dementia Research Group and carried out in Cuba, Dominican Republic, Peru, Mexico, Venezuela, Puerto Rico, China, and India on 15,376 individuals aged 65+ without dementia. Standardised assessments of mental and physical health, and cognitive function were carried out including informant interviews. An algorithm was developed to define Mayo Clinic amnestic MCI (aMCI). Disability (12-item World Health Organization disability assessment schedule [WHODAS]) and informant-reported neuropsychiatric symptoms (neuropsychiatric inventory [NPI-Q]) were measured. After adjustment, aMCI was associated with disability, anxiety, apathy, and irritability (but not depression); between-country heterogeneity in these associations was only significant for disability. The crude prevalence of aMCI ranged from 0.8% in China to 4.3% in India. Country differences changed little (range 0.6%–4.6%) after standardization for age, gender, and education level. In pooled estimates, aMCI was modestly associated with male gender and fewer assets but was not associated with age or education. There was no significant between-country variation in these demographic associations.
An algorithm-derived diagnosis of aMCI showed few sociodemographic associations but was consistently associated with higher disability and neuropsychiatric symptoms in addition to showing substantial variation in prevalence across LAMIC populations. Longitudinal data are needed to confirm findings—in particular, to investigate the predictive validity of aMCI in these settings and risk/protective factors for progression to dementia; however, the large number affected has important implications in these rapidly ageing settings.
Please see later in the article for the Editors' Summary
Editors' Summary
Currently, more than 35 million people worldwide have dementia, a group of brain disorders characterized by an irreversible decline in memory, problem solving, communication, and other “cognitive” functions. Dementia, the commonest form of which is Alzheimer's disease, mainly affects older people and, because more people than ever are living to a ripe old age, experts estimate that, by 2050, more than 115 million people will have dementia. At present, there is no cure for dementia although drugs can be used to manage some of the symptoms. Risk factors for dementia include physical inactivity, infrequent participation in mentally or socially stimulating activities, and common vascular risk factors such as high blood pressure, diabetes, and smoking. In addition, some studies have reported that mild cognitive impairment (MCI) is associated with an increased risk of dementia. MCI can be seen as an intermediate state between normal cognitive aging (becoming increasingly forgetful) and dementia although many people with MCI never develop dementia, and some types of MCI can be static or self-limiting. Individuals with MCI have cognitive problems that are more severe than those normally seen in people of a similar age but they have no other symptoms of dementia and are able to look after themselves. The best studied form of MCI—amnestic MCI (aMCI)—is characterized by memory problems such as misplacing things and forgetting appointments.
Why Was This Study Done?
Much of the expected increase in dementia will occur in low and middle income countries (LAMICs) because these countries have rapidly aging populations. Given that aMCI is frequently used to define groups of people who may be at risk of developing dementia, it would be useful to know what proportion of community-dwelling older adults in LAMICs have aMCI (the prevalence of aMCI). Such information might help governments plan their future health care and social support needs. In this cross-sectional, population-based study, the researchers estimate the prevalence of aMCI in eight LAMICs using data collected by the 10/66 Dementia Research Group. They also investigate the association of aMCI with sociodemographic factors (for example, age, gender, and education), disability, and neuropsychiatric symptoms such as anxiety, apathy, irritability, and depression. A cross-sectional study collects data on a population at a single time point; the 10/66 Dementia Research Group is building an evidence base to inform the development and implementation of policies for improving the health and social welfare of older people in LAMICs, particularly people with dementia.
What Did the Researchers Do and Find?
In cross-sectional surveys carried out in six Latin American LAMICS, China, and India, more than 15,000 elderly individuals without dementia completed standardized assessments of their mental and physical health and their cognitive function. Interviews with relatives and carers provided further details about the participant's cognitive decline and about neuropsychiatric symptoms. The researchers developed an algorithm (set of formulae) that used the data collected in these surveys to diagnose aMCI in the study participants. Finally, they used statistical methods to analyze the prevalence, distribution, and impact of aMCI in the eight LAMICs. The researchers report that aMCI was associated with disability, anxiety, apathy, and irritability but not with depression and that the prevalence of aMCI ranged from 0.8% in China to 4.3% in India. Other analyses show that, considered across all eight countries, aMCI was modestly associated with being male (men had a slightly higher prevalence of aMCI than women) and with having fewer assets but was not associated with age or education.
What Do These Findings Mean?
These findings suggest that aMCI, as diagnosed using the algorithm developed by the researchers, is consistently associated with higher disability and with neuropsychiatric symptoms in the LAMICs studied but not with most sociodemographic factors. Because prevalidated and standardized measurements were applied consistently in all the countries and a common algorithm was used to define aMCI, these findings also suggest that the prevalence of aMCI varies markedly among LAMIC populations and is similar to or slightly lower than the prevalence most often reported for European and North American populations. Although longitudinal studies are now needed to investigate the extent to which aMCI can be used as risk marker for further cognitive decline and dementia in these settings, the large absolute numbers of older people with aMCI in LAMICs revealed here potentially has important implications for health care and social service planning in these rapidly aging and populous regions of the world.
Additional Information
Please access these Web sites via the online version of this summary at
Alzheimer's Disease International is the international federation of Alzheimer associations around the world; it provides links to individual associations, information about dementia, and links to three World Alzheimer Reports; information about the 10/66 Dementia Research Group is also available on this web site
The Alzheimer's Society provides information for patients and carers about dementia, including information on MCI and personal stories about living with dementia
The Alzheimer's Association also provides information for patients and carers about dementia and about MCI, and personal stories about dementia
A BBC radio program that includes an interview with a man with MCI is available
MedlinePlus provides links to further resources about MCI and dementia (in English and Spanish)
PMCID: PMC3274506  PMID: 22346736
9.  Choroidal Proteins Involved in Cerebrospinal Fluid Production may be Potential Drug Targets for Alzheimer’s Disease Therapy 
Alzheimer’s disease is known to be the most common form of dementia in the elderly. It is clinically characterized by impairment of cognitive functions, as well as changes in personality, behavioral disturbances and an impaired ability to perform activities of daily living. To date, there are no effective ways to cure or reverse the disease. Genetic studies of early-onset familial Alzheimer’s disease cases revealed causative mutations in the genes encoding β-amyloid precursor protein and the γ-secretase-complex components presenilin-1 and presenilin-2, supporting an important role of β-amyloid in the pathogenesis of Alzheimer’s disease. Compromised function of the choroid plexus and defective cerebrospinal fluid production and turnover, with diminished clearance of β-amyloid, may play an important role in late-onset forms of Alzheimer’s disease. If reduced cerebrospinal fluid turnover is a risk factor for Alzheimer’s disease, then therapeutic strategies to improve cerebrospinal fluid flow are reasonable. However, the role of deficient cerebrospinal fluid dynamics in Alzheimer’s disease and the relevance of choroidal proteins as potential therapeutic targets to enhance cerebrospinal fluid turnover have received relatively little research attention. In this paper, we discuss several choroidal proteins, such as Na+-K+ ATPase, carbonic anhydrase, and aquaporin 1, that may be targets for pharmacological up-regulation of cerebrospinal fluid formation. The search for potentially beneficial drugs useful to ameliorate Alzheimer’s disease by facilitating cerebrospinal fluid production and turnover may be an important area for future research. However, the ultimate utility of such modulators in the management of Alzheimer’s disease remains to be determined. Here, we hypothesize that caffeine, the most commonly used psychoactive drug in the world, may be an attractive therapeutic candidate for treatment of Alzheimer’s disease since long-term caffeine consumption may augment cerebrospinal fluid production. Other potential mechanisms of cognitive protection by caffeine have been suggested by recent studies.
PMCID: PMC3072647  PMID: 21487536
Alzheimer’s disease; aquaporin 1; caffeine; carbonic anhydrase II; cerebrospinal fluid pressure; cerebrospinal fluid production; choroid plexus; intracranial pressure; Na+-K+ ATPase; SLC4A10
10.  First Diagnosis and Management of Incontinence in Older People with and without Dementia in Primary Care: A Cohort Study Using The Health Improvement Network Primary Care Database 
PLoS Medicine  2013;10(8):e1001505.
Robert Grant and colleagues used the British THIN primary care database to determine rates of first diagnosis of urinary and faecal incontinence among people aged 60–89 with dementia compared with those without dementia, and the use of medication or indwelling catheters for urinary incontinence in those with and without dementia.
Please see later in the article for the Editors' Summary
Dementia is one of the most disabling and burdensome diseases. Incontinence in people with dementia is distressing, adds to carer burden, and influences decisions to relocate people to care homes. Successful and safe management of incontinence in people with dementia presents additional challenges. The aim of this study was to investigate the rates of first diagnosis in primary care of urinary and faecal incontinence among people aged 60–89 with dementia, and the use of medication or indwelling catheters for urinary incontinence.
Methods and Findings
We extracted data on 54,816 people aged 60–89 with dementia and an age-gender stratified sample of 205,795 people without dementia from 2001 to 2010 from The Health Improvement Network (THIN), a United Kingdom primary care database. THIN includes data on patients and primary care consultations but does not identify care home residents. Rate ratios were adjusted for age, sex, and co-morbidity using multilevel Poisson regression.
The rates of first diagnosis per 1,000 person-years at risk (95% confidence interval) for urinary incontinence in the dementia cohort, among men and women, respectively, were 42.3 (40.9–43.8) and 33.5 (32.6–34.5). In the non-dementia cohort, the rates were 19.8 (19.4–20.3) and 18.6 (18.2–18.9). The rates of first diagnosis for faecal incontinence in the dementia cohort were 11.1 (10.4–11.9) and 10.1 (9.6–10.6). In the non-dementia cohort, the rates were 3.1 (2.9–3.3) and 3.6 (3.5–3.8).
The adjusted rate ratio for first diagnosis of urinary incontinence was 3.2 (2.7–3.7) in men and 2.7 (2.3–3.2) in women, and for faecal incontinence was 6.0 (5.1–7.0) in men and 4.5 (3.8–5.2) in women. The adjusted rate ratio for pharmacological treatment of urinary incontinence was 2.2 (1.4–3.7) for both genders, and for indwelling urinary catheters was 1.6 (1.3–1.9) in men and 2.3 (1.9–2.8) in women.
Compared with those without a dementia diagnosis, those with a dementia diagnosis have approximately three times the rate of diagnosis of urinary incontinence, and more than four times the rate of faecal incontinence, in UK primary care. The clinical management of urinary incontinence in people with dementia with medication and particularly the increased use of catheters is concerning and requires further investigation.
Please see later in the article for the Editors' Summary
Editors' Summary
Globally, more than 35 million people have dementia, brain disorders that are characterized by an irreversible decline in cognitive functions such as language and memory. Alzheimer's disease and other forms of dementia mainly affect older people and, because people are living longer than ever, experts estimate that by 2050 more than 115 million people will have dementia. The earliest sign of dementia is usually increasing forgetfulness but, as the disease progresses, people gradually lose their ability to deal with normal daily activities such as dressing, they may become anxious or aggressive, and they may lose control of their bladder (urinary incontinence), bowels (bowel or fecal incontinence), and other physical functions. As a result, people with dementia require increasing amounts of care as the disease progresses. Relatives and other unpaid carers provide much of this care—two-thirds of people with dementia are cared for at home. However, many people with dementia end their days in a care or nursing home.
Why Was This Study Done?
Incontinence in people with dementia is distressing for the person with dementia and for their carers and often influences decisions to move individuals into care homes. However, little is known about the diagnosis and treatment of urinary and/or fecal incontinence among people with dementia living at home. This information is needed to help policymakers commission the services required for this section of society and insurers recognize the needs such patients have, as well as helping to raise clinicians' awareness of the issue. In this cohort study (an investigation that compares outcomes in groups of people with different characteristics), the researchers use data routinely collected from general practices (primary care) in the UK to determine the rate of first diagnosis of urinary and fecal incontinence in elderly patients with and without dementia and to find out whether a diagnosis of dementia affects the rate of use of drugs or of indwelling urinary catheters (tubes inserted into the bladder to drain urine from the body) for the treatment of urinary incontinence.
What Did the Researchers Do and Find?
The researchers extracted data collected between 2001 and 2010 on incontinence for nearly 55,000 people aged 60–89 with a diagnosis of dementia (the dementia cohort) and for more than 200,000 individuals without a diagnosis of dementia (the non-dementia cohort) from The Health Improvement Network (THIN) primary care database, which includes anonymized consultation records from nearly 500 UK general practices. In the dementia cohort, the rates of first diagnosis of urinary incontinence were 42.3 and 33.5 per 1,000 person-years at risk among men and women, respectively. In the non-dementia cohort, the corresponding rates were 19.8 and 18.6. The rates of first diagnosis of fecal incontinence were 11.1 and 10.1 in the dementia cohort, and 3.1 and 3.6 in the non-dementia cohort among men and women, respectively. After adjusting for age, sex and other diseases, the adjusted rate ratio for the first diagnosis of urinary incontinence in people with dementia compared to people without dementia was 3.2 in men and 2.7 in women; for fecal incontinence, it was 6.0 in men and 4.5 in women; the adjusted rate ratio was 2.2 for both men and women for drug treatment of urinary incontinence and 1.6 in men and 2.3 in women for use of indwelling urinary catheters.
What Do These Findings Mean?
These findings indicate that, in primary care in the UK, dementia is associated with a three-fold higher rate of diagnosis of urinary incontinence and a greater than four-fold higher rate of diagnosis of fecal incontinence. Moreover, the authors suggest that some aspects of clinical management of urinary continence vary between people with and without dementia. In particular, the use of indwelling urinary catheters appears to be more common among people with dementia than among people without dementia, increasing the risk of infection. Thus, health care practitioners providing care for people with dementia may be prioritizing ease of management over risk avoidance, a possibility that requires further investigation. Although the accuracy of these findings is limited by certain aspects of the study design (for example, the THIN database does not identify which patients are living in care homes), they nevertheless suggest that policymakers and insurers involved in planning and providing services for people with dementia living at home need to provide high levels of help with incontinence, including the provision of advice and support for carers.
Additional Information
Please access these websites via the online version of this summary at
The UK not-for-profit organization Alzheimers Society provides information for patients and carers about dementia, including information on coping with incontinence and personal stories about living with dementia
The US not-for-profit organization Alzheimers Association also provides information for patients and carers about dementia and about incontinence, and personal stories about dementia
The UK National Health Service Choices website provides information (including personal stories) about dementia, urinary incontinence, and bowel incontinence
MedlinePlus provides links to further resources about dementia, urinary incontinence and fecal incontinence (in English and Spanish)
The International Continence Society and the International Consultation on Urological Diseases provide independent advice on products to manage incontinence
More information about the THIN database is available
PMCID: PMC3754889  PMID: 24015113
11.  A Randomised, Blinded, Placebo-Controlled Trial in Dementia Patients Continuing or Stopping Neuroleptics (The DART-AD Trial)  
PLoS Medicine  2008;5(4):e76.
There have been increasing concerns regarding the safety and efficacy of neuroleptics in people with dementia, but there are very few long-term trials to inform clinical practice. The aim of this study was to determine the impact of long-term treatment with neuroleptic agents upon global cognitive decline and neuropsychiatric symptoms in patients with Alzheimer disease.
Methods and Findings
Design: Randomised, blinded, placebo-controlled parallel two-group treatment discontinuation trial.
Setting: Oxfordshire, Newcastle and Gateshead, London and Edinburgh, United Kingdom.
Participants: Patients currently prescribed the neuroleptics thioridazine, chlorpromazine, haloperidol trifluoperazine or risperidone for behavioural or psychiatric disturbance in dementia for at least 3 mo.
Interventions: Continue neuroleptic treatment for 12 mo or switch to an identical placebo.
Outcome measures: Primary outcome was total Severe Impairment Battery (SIB) score. Neuropsychiatric symptoms were evaluated with the Neuropsychiatric Inventory (NPI).
Results: 165 patients were randomised (83 to continue treatment and 82 to placebo, i.e., discontinue treatment), of whom 128 (78%) commenced treatment (64 continue/64 placebo). Of those, 26 were lost to follow-up (13 per arm), resulting in 51 patients per arm analysed for the primary outcome. There was no significant difference between the continue treatment and placebo groups in the estimated mean change in SIB scores between baseline and 6 mo; estimated mean difference in deterioration (favouring placebo) −0.4 (95% confidence interval [CI] −6.4 to 5.5), adjusted for baseline value (p = 0.9). For neuropsychiatric symptoms, there was no significant difference between the continue treatment and placebo groups (n = 56 and 53, respectively) in the estimated mean change in NPI scores between baseline and 6 mo; estimated mean difference in deterioration (favouring continue treatment) −2.4 (95% CI −8.2 to 3.5), adjusted for baseline value (p = 0.4). Both results became more pronounced at 12 mo. There was some evidence to suggest that those patients with initial NPI ≥ 15 benefited on neuropsychiatric symptoms from continuing treatment.
For most patients with AD, withdrawal of neuroleptics had no overall detrimental effect on functional and cognitive status. Neuroleptics may have some value in the maintenance treatment of more severe neuropsychiatric symptoms, but this benefit must be weighed against the side effects of therapy.
Trial registration: Cochrane Central Registry of Controlled Trials/National Research Register (#ISRCTN33368770).
In a randomized trial of patients with dementia, Clive Ballard and colleagues show that withdrawal of neuroleptics had no overall detrimental effect, and by some measures improved, functional and cognitive status.
Editors' Summary
The number of people with dementia (currently 25 million worldwide) is expected to increase by 5 million each year. The risk of dementia, including Alzheimer disease, increases sharply with age: Alzheimer's Disease International estimates that 1.4% of people 65–69 have dementia, whereas almost a full quarter of those over the age of 85 years are affected. Almost all older dementia patients will experience, along with the cognitive and functional decline typical of the illness, some neuropsychiatric symptoms. These symptoms can include agitation, aggression, and psychosis, and are often devastating for the older patient and his or her family and caregiver. Managing these symptoms is often a prime concern for health-care providers and families. Neuroleptics (sometimes called antipsychotics) are the class of drugs often used to manage or control neuropsychiatric problems, but there have been questions about their safety and appropriateness. Safety concerns involve risk of stroke, parkinsonism, sedation, edema, and chest infections but also include a worsening of cognitive decline with prolonged use of neuroleptics.
Why Was the Study Done?
Previous studies on the effectiveness and safety of neuroleptics in older people have been short term. Ballard and colleagues wanted to study over a longer period of time the impact of neuroleptic drugs on elderly patients with dementia. Specifically, they wanted to know if being on a neuroleptic was associated with more cognitive decline than coming off the drug. They also wanted to investigate whether discontinuing the drug exacerbated any neuropsychiatric symptoms, Parkinson disease-like symptoms, or other functional, language, and cognition difficulties frequently associated with dementia.
What Did the Researchers Do and Find?
The researchers recruited older patients with Alzheimer disease from across England who had been on neuroleptics for at least three months. They randomised patients to one of two groups: the first group continued taking the same neuroleptic at the same dosage level while the second group was switched to an identical-looking placebo. The researchers assessed the patients' cognitive status and neuropsychiatric symptoms upon their entry into the study. Six and 12 months later the researchers assessed any cognitive decline and the level of neuropsychiatric and other problems that patients were experiencing.
At both 6 and 12 months, the researchers found that there were no differences between the two groups (continued treatment and placebo) in terms of cognitive decline. The placebo group may have had less cognitive decline, but this was not statistically significant. They also found no overall differences between the two groups in the change in the number of neuropsychiatric symptoms over these time periods. Patients with severe neuropsychiatric problems at the outset of the trial did better on continued neuroleptic therapy, but this advantage was not statistically significant. There was a significant decline on the verbal fluency language tests among the patients who continued on their neuroleptic.
What Do these Findings Mean?
The researchers report perhaps the first trial of this duration on continued versus withdrawn neuroleptic treatment among older dementia patients. The findings do not indicate any benefit of continuing neuroleptic therapies in older patients on either cognitive or neuropsychiatric outcomes. The researchers conclude that neuroleptics, with their known safety issues, should not be used as first-line treatment to manage problems such as agitation or aggression. For older dementia patients whose neuropsychiatric symptoms are not remedied by nonpharmaceutical treatments, the researchers advise caution. More studies are urgently needed to find better solutions to help older patients with dementia who have agitation, aggression, and psychosis.
Additional Information
Please access these Web sites via the online version of this summary at
Alzheimer's Disease International is an umbrella organisation of organisations worldwide
The Alzheimer's Research Trust in the UK is a charity funding research to cure or prevent dementias
The US National Institutes of Aging has information on Alzheimer Disease in English and Spanish
Two governmental regulatory agencies—the Medicines and Healthcare Products Regulatory Agency in the UK and the Food and Drug Administration in the US—offer information about antipsychotics in people with dementia
PMCID: PMC2276521  PMID: 18384230
12.  Preclinical syndromes predict dementia: the Sydney older persons study 
OBJECTIVES—To identify if preclinical syndromes for Alzheimer's disease, vascular dementia, and Parkinson's disease and related dementias exist. Identification of dementia at early or even preclinical stages has important implications for treatment.
METHODS—A community dwelling sample of 647 subjects aged 75 and over at recruitment were followed up for a mean period of 3.19 years (range 2.61 to 4.51 years). Each subject was asked to participate in a medical assessment which included a standardised medical history examining both past and current health and medication usage; a neuropsychological battery (mini mental state examination, Reid memory test, verbal fluency, subsets of the Boston naming test and similarities, clock drawing and copied drawings) and physical examination. Preclinical syndromes for the three predominant dementias (Alzheimer's disease, vascular dementia and Parkinson's disease, and related dementias) and their combinations were defined using cognitive, motor, and vascular features. Their longitudinal outcome as defined by death and dementia incidence was examined.
RESULTS—Preclinical syndromes affected 55.7% (n=299) of subjects. Preclinical syndromes showed a trend for an increased odds of death (odds ratio 1.72, p=0.056) and a significantly increased odds of developing dementia (odds ratio 4.81, p<0.001). Preclinical syndromes were highly sensitive, detecting 52 of 58 (89.7%) incident dementias. Two hundred and sixteen of 268 (80.6%) preclinical subjects did not show dementia over the 3 year period (positive predictive value 19.4%). Subjects defined as having a combination of cognitive, extrapyramidal, and vascular features were at greatest risk of progressing to dementia.
CONCLUSIONS—Preclinical syndromes were sensitive and significant predictors of dementia. In view of their poor positive predictive value, the preclinical syndromes as defined in this study remain a research tool needing both definitional refinement and greater periods of observation. Multiple coexistent preclinical disorders resulted in a greater incidence of dementia, providing evidence for an additive role between multiple disorders.

PMCID: PMC1737538  PMID: 11511700
13.  Caregiver- and Patient-Directed Interventions for Dementia 
Executive Summary
In early August 2007, the Medical Advisory Secretariat began work on the Aging in the Community project, an evidence-based review of the literature surrounding healthy aging in the community. The Health System Strategy Division at the Ministry of Health and Long-Term Care subsequently asked the secretariat to provide an evidentiary platform for the ministry’s newly released Aging at Home Strategy.
After a broad literature review and consultation with experts, the secretariat identified 4 key areas that strongly predict an elderly person’s transition from independent community living to a long-term care home. Evidence-based analyses have been prepared for each of these 4 areas: falls and fall-related injuries, urinary incontinence, dementia, and social isolation. For the first area, falls and fall-related injuries, an economic model is described in a separate report.
Please visit the Medical Advisory Secretariat Web site,, to review these titles within the Aging in the Community series.
Aging in the Community: Summary of Evidence-Based Analyses
Prevention of Falls and Fall-Related Injuries in Community-Dwelling Seniors: An Evidence-Based Analysis
Behavioural Interventions for Urinary Incontinence in Community-Dwelling Seniors: An Evidence-Based Analysis
Caregiver- and Patient-Directed Interventions for Dementia: An Evidence-Based Analysis
Social Isolation in Community-Dwelling Seniors: An Evidence-Based Analysis
The Falls/Fractures Economic Model in Ontario Residents Aged 65 Years and Over (FEMOR)
This report features the evidence-based analysis on caregiver- and patient-directed interventions for dementia and is broken down into 4 sections:
Caregiver-Directed Interventions for Dementia
Patient-Directed Interventions for Dementia
Economic Analysis of Caregiver- and Patient-Directed Interventions for Dementia
Caregiver-Directed Interventions for Dementia
To identify interventions that may be effective in supporting the well-being of unpaid caregivers of seniors with dementia living in the community.
Clinical Need: Target Population and Condition
Dementia is a progressive and largely irreversible syndrome that is characterized by a loss of cognitive function severe enough to impact social or occupational functioning. The components of cognitive function affected include memory and learning, attention, concentration and orientation, problem-solving, calculation, language, and geographic orientation. Dementia was identified as one of the key predictors in a senior’s transition from independent community living to admission to a long-term care (LTC) home, in that approximately 90% of individuals diagnosed with dementia will be institutionalized before death. In addition, cognitive decline linked to dementia is one of the most commonly cited reasons for institutionalization.
Prevalence estimates of dementia in the Ontario population have largely been extrapolated from the Canadian Study of Health and Aging conducted in 1991. Based on these estimates, it is projected that there will be approximately 165,000 dementia cases in Ontario in the year 2008, and by 2010 the number of cases will increase by nearly 17% over 2005 levels. By 2020 the number of cases is expected to increase by nearly 55%, due to a rise in the number of people in the age categories with the highest prevalence (85+). With the increase in the aging population, dementia will continue to have a significant economic impact on the Canadian health care system. In 1991, the total costs associated with dementia in Canada were $3.9 billion (Cdn) with $2.18 billion coming from LTC.
Caregivers play a crucial role in the management of individuals with dementia because of the high level of dependency and morbidity associated with the condition. It has been documented that a greater demand is faced by dementia caregivers compared with caregivers of persons with other chronic diseases. The increased burden of caregiving contributes to a host of chronic health problems seen among many informal caregivers of persons with dementia. Much of this burden results from managing the behavioural and psychological symptoms of dementia (BPSD), which have been established as a predictor of institutionalization for elderly patients with dementia.
It is recognized that for some patients with dementia, an LTC facility can provide the most appropriate care; however, many patients move into LTC unnecessarily. For individuals with dementia to remain in the community longer, caregivers require many types of formal and informal support services to alleviate the stress of caregiving. These include both respite care and psychosocial interventions. Psychosocial interventions encompass a broad range of interventions such as psychoeducational interventions, counseling, supportive therapy, and behavioural interventions.
Assuming that 50% of persons with dementia live in the community, a conservative estimate of the number of informal caregivers in Ontario is 82,500. Accounting for the fact that 29% of people with dementia live alone, this leaves a remaining estimate of 58,575 Ontarians providing care for a person with dementia with whom they reside.
Description of Interventions
The 2 main categories of caregiver-directed interventions examined in this review are respite care and psychosocial interventions. Respite care is defined as a break or relief for the caregiver. In most cases, respite is provided in the home, through day programs, or at institutions (usually 30 days or less). Depending on a caregiver’s needs, respite services will vary in delivery and duration. Respite care is carried out by a variety of individuals, including paid staff, volunteers, family, or friends.
Psychosocial interventions encompass a broad range of interventions and have been classified in various ways in the literature. This review will examine educational, behavioural, dementia-specific, supportive, and coping interventions. The analysis focuses on behavioural interventions, that is, those designed to help the caregiver manage BPSD. As described earlier, BPSD are one of the most challenging aspects of caring for a senior with dementia, causing an increase in caregiver burden. The analysis also examines multicomponent interventions, which include at least 2 of the above-mentioned interventions.
Methods of Evidence-Based Analysis
A comprehensive search strategy was used to identify systematic reviews and randomized controlled trials (RCTs) that examined the effectiveness of interventions for caregivers of dementia patients.
Section 2.1
Are respite care services effective in supporting the well-being of unpaid caregivers of seniors with dementia in the community?
Do respite care services impact on rates of institutionalization of these seniors?
Section 2.2
Which psychosocial interventions are effective in supporting the well-being of unpaid caregivers of seniors with dementia in the community?
Which interventions reduce the risk for institutionalization of seniors with dementia?
Outcomes of Interest
any quantitative measure of caregiver psychological health, including caregiver burden, depression, quality of life, well-being, strain, mastery (taking control of one’s situation), reactivity to behaviour problems, etc.;
rate of institutionalization; and
Assessment of Quality of Evidence
The quality of the evidence was assessed as High, Moderate, Low, or Very low according to the GRADE methodology and GRADE Working Group. As per GRADE the following definitions apply:
Summary of Findings
Conclusions in Table 1 are drawn from Sections 2.1 and 2.2 of the report.
Summary of Conclusions on Caregiver-Directed Interventions
There is limited evidence from RCTs that respite care is effective in improving outcomes for those caring for seniors with dementia.
There is considerable qualitative evidence of the perceived benefits of respite care.
Respite care is known as one of the key formal support services for alleviating caregiver burden in those caring for dementia patients.
Respite care services need to be tailored to individual caregiver needs as there are vast differences among caregivers and patients with dementia (severity, type of dementia, amount of informal/formal support available, housing situation, etc.)
There is moderate- to high-quality evidence that individual behavioural interventions (≥ 6 sessions), directed towards the caregiver (or combined with the patient) are effective in improving psychological health in dementia caregivers.
There is moderate- to high-quality evidence that multicomponent interventions improve caregiver psychosocial health and may affect rates of institutionalization of dementia patients.
RCT indicates randomized controlled trial.
Patient-Directed Interventions for Dementia
The section on patient-directed interventions for dementia is broken down into 4 subsections with the following questions:
3.1 Physical Exercise for Seniors with Dementia – Secondary Prevention
What is the effectiveness of physical exercise for the improvement or maintenance of basic activities of daily living (ADLs), such as eating, bathing, toileting, and functional ability, in seniors with mild to moderate dementia?
3.2 Nonpharmacologic and Nonexercise Interventions to Improve Cognitive Functioning in Seniors With Dementia – Secondary Prevention
What is the effectiveness of nonpharmacologic interventions to improve cognitive functioning in seniors with mild to moderate dementia?
3.3 Physical Exercise for Delaying the Onset of Dementia – Primary Prevention
Can exercise decrease the risk of subsequent cognitive decline/dementia?
3.4 Cognitive Interventions for Delaying the Onset of Dementia – Primary Prevention
Does cognitive training decrease the risk of cognitive impairment, deterioration in the performance of basic ADLs or instrumental activities of daily living (IADLs),1 or incidence of dementia in seniors with good cognitive and physical functioning?
Clinical Need: Target Population and Condition
Secondary Prevention2
Physical deterioration is linked to dementia. This is thought to be due to reduced muscle mass leading to decreased activity levels and muscle atrophy, increasing the potential for unsafe mobility while performing basic ADLs such as eating, bathing, toileting, and functional ability.
Improved physical conditioning for seniors with dementia may extend their independent mobility and maintain performance of ADL.
Nonpharmacologic and Nonexercise Interventions
Cognitive impairments, including memory problems, are a defining feature of dementia. These impairments can lead to anxiety, depression, and withdrawal from activities. The impact of these cognitive problems on daily activities increases pressure on caregivers.
Cognitive interventions aim to improve these impairments in people with mild to moderate dementia.
Primary Prevention3
Various vascular risk factors have been found to contribute to the development of dementia (e.g., hypertension, hypercholesterolemia, diabetes, overweight).
Physical exercise is important in promoting overall and vascular health. However, it is unclear whether physical exercise can decrease the risk of cognitive decline/dementia.
Nonpharmacologic and Nonexercise Interventions
Having more years of education (i.e., a higher cognitive reserve) is associated with a lower prevalence of dementia in crossectional population-based studies and a lower incidence of dementia in cohorts followed longitudinally. However, it is unclear whether cognitive training can increase cognitive reserve or decrease the risk of cognitive impairment, prevent or delay deterioration in the performance of ADLs or IADLs or reduce the incidence of dementia.
Description of Interventions
Physical exercise and nonpharmacologic/nonexercise interventions (e.g., cognitive training) for the primary and secondary prevention of dementia are assessed in this review.
Evidence-Based Analysis Methods
A comprehensive search strategy was used to identify systematic reviews and RCTs that examined the effectiveness, safety and cost effectiveness of exercise and cognitive interventions for the primary and secondary prevention of dementia.
Section 3.1: What is the effectiveness of physical exercise for the improvement or maintenance of ADLs in seniors with mild to moderate dementia?
Section 3.2: What is the effectiveness of nonpharmacologic/nonexercise interventions to improve cognitive functioning in seniors with mild to moderate dementia?
Section 3.3: Can exercise decrease the risk of subsequent cognitive decline/dementia?
Section 3.4: Does cognitive training decrease the risk of cognitive impairment, prevent or delay deterioration in the performance of ADLs or IADLs, or reduce the incidence of dementia in seniors with good cognitive and physical functioning?
Assessment of Quality of Evidence
The quality of the evidence was assessed as High, Moderate, Low, or Very low according to the GRADE methodology. As per GRADE the following definitions apply:
Summary of Findings
Table 2 summarizes the conclusions from Sections 3.1 through 3.4.
Summary of Conclusions on Patient-Directed Interventions*
Previous systematic review indicated that “cognitive training” is not effective in patients with dementia.
A recent RCT suggests that CST (up to 7 weeks) is effective for improving cognitive function and quality of life in patients with dementia.
Regular leisure time physical activity in midlife is associated with a reduced risk of dementia in later life (mean follow-up 21 years).
Regular physical activity in seniors is associated with a reduced risk of cognitive decline (mean follow-up 2 years).
Regular physical activity in seniors is associated with a reduced risk of dementia (mean follow-up 6–7 years).
Evidence that cognitive training for specific functions (memory, reasoning, and speed of processing) produces improvements in these specific domains.
Limited inconclusive evidence that cognitive training can offset deterioration in the performance of self-reported IADL scores and performance assessments.
1° indicates primary; 2°, secondary; CST, cognitive stimulation therapy; IADL, instrumental activities of daily living; RCT, randomized controlled trial.
Benefit/Risk Analysis
As per the GRADE Working Group, the overall recommendations consider 4 main factors:
the trade-offs, taking into account the estimated size of the effect for the main outcome, the confidence limits around those estimates, and the relative value placed on the outcome;
the quality of the evidence;
translation of the evidence into practice in a specific setting, taking into consideration important factors that could be expected to modify the size of the expected effects such as proximity to a hospital or availability of necessary expertise; and
uncertainty about the baseline risk for the population of interest.
The GRADE Working Group also recommends that incremental costs of health care alternatives should be considered explicitly alongside the expected health benefits and harms. Recommendations rely on judgments about the value of the incremental health benefits in relation to the incremental costs. The last column in Table 3 reflects the overall trade-off between benefits and harms (adverse events) and incorporates any risk/uncertainty (cost-effectiveness).
Overall Summary Statement of the Benefit and Risk for Patient-Directed Interventions*
Economic Analysis
Budget Impact Analysis of Effective Interventions for Dementia
Caregiver-directed behavioural techniques and patient-directed exercise programs were found to be effective when assessing mild to moderate dementia outcomes in seniors living in the community. Therefore, an annual budget impact was calculated based on eligible seniors in the community with mild and moderate dementia and their respective caregivers who were willing to participate in interventional home sessions. Table 4 describes the annual budget impact for these interventions.
Annual Budget Impact (2008 Canadian Dollars)
Assumed 7% prevalence of dementia aged 65+ in Ontario.
Assumed 8 weekly sessions plus 4 monthly phone calls.
Assumed 12 weekly sessions plus biweekly sessions thereafter (total of 20).
Assumed 2 sessions per week for first 5 weeks. Assumed 90% of seniors in the community with dementia have mild to moderate disease. Assumed 4.5% of seniors 65+ are in long-term care, and the remainder are in the community. Assumed a rate of participation of 60% for both patients and caregivers and of 41% for patient-directed exercise. Assumed 100% compliance since intervention administered at the home. Cost for trained staff from Ministry of Health and Long-Term Care data source. Assumed cost of personal support worker to be equivalent to in-home support. Cost for recreation therapist from Alberta government Website.
Note: This budget impact analysis was calculated for the first year after introducing the interventions from the Ministry of Health and Long-Term Care perspective using prevalence data only. Prevalence estimates are for seniors in the community with mild to moderate dementia and their respective caregivers who are willing to participate in an interventional session administered at the home setting. Incidence and mortality rates were not factored in. Current expenditures in the province are unknown and therefore were not included in the analysis. Numbers may change based on population trends, rate of intervention uptake, trends in current programs in place in the province, and assumptions on costs. The number of patients was based on patients likely to access these interventions in Ontario based on assumptions stated below from the literature. An expert panel confirmed resource consumption.
PMCID: PMC3377513  PMID: 23074509
14.  Regional brain volume differences in symptomatic and presymptomatic carriers of familial Alzheimer’s disease mutations 
Mutations in the presenilin (PSEN1, PSEN2) and amyloid precursor protein (APP) genes cause familial Alzheimer’s disease (FAD) in a nearly fully penetrant, autosomal dominant manner, providing a unique opportunity to study presymptomatic individuals who can be predicted to develop Alzheimer’s disease (AD) with essentially 100% certainty. Using tensor-based morphometry (TBM), we examined brain volume differences between presymptomatic and symptomatic FAD mutation carriers and non-carrier (NC) relatives.
Twenty-five mutation carriers and 10 NC relatives underwent brain MRI and clinical assessment. Four mutation carriers had dementia (MUT-Dem), 12 had amnestic mild cognitive impairment (MUT-aMCI) and nine were cognitively normal (MUT-Norm). TBM brain volume maps of MUT-Norm, MUT-aMCI and MUT-Dem subjects were compared to NC subjects.
MUT-Norm subjects exhibited significantly smaller volumes in the thalamus, caudate and putamen. MUT-aMCI subjects had smaller volumes in the thalamus, splenium and pons, but not in the caudate or putamen. MUT-Dem subjects demonstrated smaller volumes in temporal, parietal and left frontal regions. As non-demented carriers approached the expected age of dementia diagnosis, this was associated with larger ventricular and caudate volumes and a trend towards smaller temporal lobe volume.
Cognitively intact FAD mutation carriers had lower thalamic, caudate and putamen volumes, and we found preliminary evidence for increasing caudate size during the predementia stage. These regions may be affected earliest during prodromal stages of FAD, while cortical atrophy may occur in later stages, when carriers show cognitive deficits. Further studies of this population will help us understand the progression of neurobiological changes in AD.
PMCID: PMC3779052  PMID: 23085935
15.  Relationship of dementia screening tests with biomarkers of Alzheimer’s disease 
Brain  2010;133(11):3290-3300.
Screening tests for Alzheimer’s disease lack sensitivity and specificity. We developed the AD8, a brief dementia screening interview validated against clinical and cognitive evaluations, as an improvement over current screening methods. Because insufficient follow-up has occurred to validate the AD8 against the neuropathologic findings of Alzheimer’s disease, we investigated whether AD8 scores correspond to impairment in episodic memory testing and changes in biomarkers of Alzheimer’s disease (cerebrospinal fluid and amyloid imaging with Pittsburgh compound B) characteristic of symptomatic Alzheimer’s disease. We also compared informant-based assessments with brief performance-based dementia screening measurements such as the Mini Mental State Exam. The sample (n = 257) had a mean age of 75.4 years with 15.1 years of education; 88.7% were Caucasian and 45.5% were male. The sample was divided into two groups based on their AD8 scores: those with a negative dementia screening test (AD8 score 0 or 1, n = 137) and those with a positive dementia screening test (AD8 score ≥2, n = 120). Individuals with positive AD8 scores had abnormal Pittsburgh compound B binding (P < 0.001) and cerebrospinal fluid biomarkers (P < 0.001) compared with individuals with negative AD8 scores. Individuals with positive AD8 tests and positive biomarkers scored in the impaired range on the Wechsler Logical Memory Story A (mean score 7.0 ± 4.5 for Pittsburgh compound B; mean score 7.6 ± 5.3 for cerebrospinal fluid amyloid beta protein 1–42). The AD8 area under the curve for Pittsburgh compound B was 0.737 (95% confidence interval: 0.64–0.83) and for cerebrospinal fluid amyloid beta protein 1–42 was 0.685 (95% confidence interval: 0.60–0.77) suggesting good discrimination. The AD8 had superior sensitivity in detecting early stages of dementia compared with the Mini Mental State Examination. The AD8 had a likelihood ratio of a positive test of 5.8 (95% confidence interval: 5.4–6.3) and likelihood ratio of a negative test of 0.04 (95% confidence interval: 0.03–0.06), increasing the pre-test probability of an individual having symptomatic Alzheimer’s disease. Individuals with AD8 scores of ≥2 had a biomarker phenotype consistent with Alzheimer’s disease and lower performance on episodic memory tests, supporting a diagnosis of Alzheimer’s disease. Informant-based assessments may be superior to performance-based screening measures such as the Mini Mental State Examination in corresponding to underlying Alzheimer’s disease pathology, particularly at the earliest stages of decline. The use of a brief test such as the AD8 may improve strategies for detecting dementia in community settings where biomarkers may not be readily available, and may enrich clinical trial recruitment by increasing the likelihood that participants have underlying biomarker abnormalities.
PMCID: PMC2965421  PMID: 20823087
AD8; Alzheimer’s disease; screening; biomarkers; preclinical; cognition
16.  Metal protein attenuating compounds for the treatment of Alzheimer’s dementia 
Alzheimer’s dementia (AD) may be caused by the formation of extracellular senile plaques comprised of beta-amyloid (Aß). In vitro and mouse model studies have demonstrated that metal protein attenuating compounds (MPACs) promote the solubilisation and clearance of Aß.
To evaluate the efficacy of metal protein attenuating compounds (MPACs) for the treatment of cognitive impairment due to Alzheimer’s dementia.
Search methods
We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group Specialized Register, on 29 July 2010 using the terms: Clioquinol OR PBT1 OR PBT2 OR “metal protein” OR MPACS OR MPAC.
Selection criteria
Randomised double-blind trials in which treatment with an MPAC was administered to participants with Alzheimer’s dementia in a parallel group comparison with placebo were included.
Data collection and analysis
Three review authors (RM, LJ, ELS) independently assessed the quality of trials according to the Cochrane Handbook for Systematic Reviews of Interventions.
The primary outcome measure of interest was cognitive function (as measured by psychometric tests). The secondary outcome measures of interest were in the following areas: quality of life, functional performance, effect on carer, biomarkers, safety and adverse effects, and death.
Main results
Two MPAC trials were identified. One trial compared clioquinol (PBT1) with placebo in 36 patients and 32 had sufficient data for per protocol analysis. There was no statistically significant difference in cognition (as measured on the Alzheimer’s Disease Assessment Scale - Cognition (ADAS-Cog)) between the active treatment and placebo groups at 36 weeks. The difference in mean change from baseline ADAS-Cog score in the clioquinol arm compared with the placebo arm at weeks 24 and 36 was a difference of 7.37 (95% confidence interval (CI) 1.51 to 13.24) and 6.36 (95% CI −0.50 to 13.23), respectively. There was no significant impact on non-cognitive symptoms or clinical global impression. One participant in the active treatment group developed neurological symptoms (impaired visual acuity and colour vision) which resolved on cessation of treatment and were possibly attributable to the drug.
In the second trial a successor compound, PBT2, was compared with placebo in 78 participants with mild Alzheimer’s dementia; all were included in the intention-to-treat analysis. There was no significant difference in the Neuropsychological Test Battery (NTB) composite, memory or executive scores between placebo and PBT2 in the least squares mean change from baseline at week 12. However, two executive function component tests of the NTB showed significant improvement over placebo in the PBT2 250 mg group from baseline to week 12: category fluency test (2.8 words, 95% CI 0.1 to 5.4; P = 0.041) and trail making part B (−48.0 s, 95% CI −83.0 to −13.0; P = 0.009). In the executive factor Z score, the difference in least squares mean change from baseline at week 12 for PBT2 250 mg compared with placebo was 0·27 (0·01 to 0·53; p=0·042). There was no significant effect on cognition on Mini-Mental State Examination (MMSE) or ADAS-Cog scales. PBT2 had a favourable safety profile.
Authors’ conclusions
There is an absence of evidence as to whether clioquinol (PBT1) has any positive clinical benefit for patients with AD, or whether the drug is safe. We have some concerns about the quality of the study methodology; there was an imbalance in treatment and control groups after randomisation (participants in the active treatment group had a higher mean pre-morbid IQ) and the secondary analyses of results stratified by baseline dementia severity. The planned phase III trial of PBT1 has been abandoned and this compound has been withdrawn from development. The second trial of PBT2 was more rigorously conducted and showed that after 12 weeks this compound appeared to be safe and well tolerated in people with mild Alzheimer’s dementia. Larger trials are now required to demonstrate cognitive efficacy.
PMCID: PMC4165331  PMID: 22592705
Alzheimer Disease [*drug therapy]; Chelating Agents [adverse effects; *therapeutic use]; Clioquinol [adverse effects; *analogs & derivatives; *therapeutic use]; Randomized Controlled Trials as Topic; Aged; Humans
17.  Cognitive training and cognitive rehabilitation for persons with mild to moderate dementia of the Alzheimer's or vascular type: a review 
Cognitive impairments, and particularly memory deficits, are a defining feature of the early stages of Alzheimer's disease and vascular dementia. Interventions that target these cognitive deficits and the associated difficulties with activities of daily living are the subject of ever-growing interest. Cognitive training and cognitive rehabilitation are specific forms of non-pharmacological intervention to address cognitive and non-cognitive outcomes. The present review is an abridged version of a Cochrane Review and aims to systematically evaluate the evidence for these forms of intervention in people with mild Alzheimer's disease or vascular dementia. Randomized controlled trials (RCTs), published in English, comparing cognitive rehabilitation or cognitive training interventions with control conditions and reporting relevant outcomes for the person with dementia or the family caregiver (or both), were considered for inclusion. Eleven RCTs reporting cognitive training interventions were included in the review. A large number of measures were used in the different studies, and meta-analysis could be conducted for several primary and secondary outcomes of interest. Several outcomes were not measured in any of the studies. Overall estimates of the treatment effect were calculated by using a fixed-effects model, and statistical heterogeneity was measured by using a standard chi-squared statistic. One RCT of cognitive rehabilitation was identified, allowing the examination of effect sizes, but no meta-analysis could be conducted. Cognitive training was not associated with positive or negative effects in relation to any of the reported outcomes. The overall quality of the trials was low to moderate. The single RCT of cognitive rehabilitation found promising results in relation to some patient and caregiver outcomes and was generally of high quality. The available evidence regarding cognitive training remains limited, and the quality of the evidence needs to improve. However, there is still no indication of any significant benefits from cognitive training. Trial reports indicate that some gains resulting from intervention may not be captured adequately by available standardized outcome measures. The results of the single RCT of cognitive rehabilitation show promise but are preliminary in nature. Further well-designed studies of cognitive training and cognitive rehabilitation are required to provide more definitive evidence. Researchers should describe and classify their interventions appropriately by using the available terminology.
PMCID: PMC3979126  PMID: 23924584
18.  Severity of CIND and MCI predict incidence of dementia in an ischemic stroke cohort 
Neurology  2009;73(22):1866-1872.
The utility of poststroke cognitive status, namely dementia, cognitive impairment no dementia (CIND), mild cognitive impairment (MCI), and no cognitive impairment (NCI), in predicting dementia has been previously examined. However, no studies to date have compared the ability of subtypes of MCI and CIND to predict dementia in a poststroke population.
A cohort of ischemic stroke patients underwent neuropsychological assessment annually for up to 5 years. Dementia was defined using the DSM-IV criteria. Univariate and multivariable Cox proportional regression was performed to determine the ability of MCI subtypes, CIND severity, and individual domains of impairment to predict dementia.
A total of 362 patients without dementia were followed up for a mean of 3.4 years (17% drop out), with 24 developing incident dementia. Older age, previous and recurrent stroke, and CIND and MCI subtypes were significant predictors of dementia. In multivariable analysis controlling for treatment allocation, patients who were older, had previous or recurrent stroke, and had either CIND moderate or multiple domain MCI with amnestic component were at elevated risk for dementia. In multivariable domain analysis, recurrent strokes, age, and previous strokes, verbal memory, and visual memory were significant predictors of dementia. Receiver operating characteristic curve analysis showed that CIND moderate (area under the curve: 0.893) and multiple domain MCI with amnestic component (area under the curve: 0.832) were significant predictors of conversion to dementia. All other classifications of cognitive impairment had areas under the curve less than 0.7.
Stroke patients with cognitive impairment no dementia (CIND) moderate are at higher risk of developing dementia, while CIND mild patients are not at increased risk of developing dementia.
= Alzheimer disease;
= area under the curve;
= confidence interval;
= cognitive impairment no dementia;
= Diagnostic and Statistical Manual of Mental Disorders, 4th edition;
= European Australasian Stroke Prevention in Reversible Ischemia Trial;
= European Australasian Stroke Prevention in Reversible Ischemia Trial, cognitive substudy;
= hazard ratio;
= lacunar infarct;
= mild cognitive impairment;
= modified Rankin scale;
= no cognitive impairment;
= Oxfordshire Community Stroke Project;
= partial anterior circulation infarct;
= posterior circulation infarct;
= receiver operating curve;
= total anterior circulation infarct;
= vascular dementia;
= Wechsler Adult Intelligence Scale–Revised;
= Wechsler Memory Scale–Revised.
PMCID: PMC2788800  PMID: 19949033
19.  Measuring clinical progression in MCI and pre-MCI populations: enrichment and optimizing clinical outcomes over time 
Recent biomarker research has improved the identification of individuals with very early stages of Alzheimer's disease (AD) and has demonstrated that biomarkers are sensitive for measuring progression in the pre-dementia or mild cognitive impairment (MCI) stage and even pre-symptomatic or pre-MCI stage of AD. Because there are no validated biomarkers in AD, it is important to seek out clinical outcomes that are also sensitive for measuring progression in these very early stages of disease. Clinical outcomes are more subjective and more affected by measurement error than biomarkers but represent the core aspects of the disease and are critical for validation of biomarkers and for evaluation of clinical relevance. Identification of individuals with pre-MCI stages of AD will need to continue to rely on biomarkers, but the identification of individuals with MCI who will progress to AD can be achieved with biomarkers or clinical criteria. Although standard clinical outcomes have been shown to be less sensitive to progression than biomarker outcomes in MCI and pre-MCI populations, non-standard scoring has improved the performance of the Alzheimer's Disease Assessment Scale cognitive subscale, making it more sensitive to progression. Neuropsychological cognitive testing items are optimal for measuring progression in pre-MCI populations, and current research is exploring the best ways to combine these items into a composite cognitive score with maximum responsiveness. In an MCI stage, cognitive, functional, and global items all change, and the best single composite score for measuring progression may involve all of these aspects of the disease. The best chance of success in demonstrating treatment effects in clinical trials will be achieved in a well-defined pre-MCI or MCI population and with an outcome that tracks well with clinical progression over time and with time. A partial least squares model can be used to identify these optimal weighted combinations.
PMCID: PMC3506938  PMID: 22805433
20.  Connected speech as a marker of disease progression in autopsy-proven Alzheimer’s disease 
Brain  2013;136(12):3727-3737.
Although an insidious history of episodic memory difficulty is a typical presenting symptom of Alzheimer’s disease, detailed neuropsychological profiling frequently demonstrates deficits in other cognitive domains, including language. Previous studies from our group have shown that language changes may be reflected in connected speech production in the earliest stages of typical Alzheimer’s disease. The aim of the present study was to identify features of connected speech that could be used to examine longitudinal profiles of impairment in Alzheimer’s disease. Samples of connected speech were obtained from 15 former participants in a longitudinal cohort study of ageing and dementia, in whom Alzheimer’s disease was diagnosed during life and confirmed at post-mortem. All patients met clinical and neuropsychological criteria for mild cognitive impairment between 6 and 18 months before converting to a status of probable Alzheimer’s disease. In a subset of these patients neuropsychological data were available, both at the point of conversion to Alzheimer’s disease, and after disease severity had progressed from the mild to moderate stage. Connected speech samples from these patients were examined at later disease stages. Spoken language samples were obtained using the Cookie Theft picture description task. Samples were analysed using measures of syntactic complexity, lexical content, speech production, fluency and semantic content. Individual case analysis revealed that subtle changes in language were evident during the prodromal stages of Alzheimer’s disease, with two-thirds of patients with mild cognitive impairment showing significant but heterogeneous changes in connected speech. However, impairments at the mild cognitive impairment stage did not necessarily entail deficits at mild or moderate stages of disease, suggesting non-language influences on some aspects of performance. Subsequent examination of these measures revealed significant linear trends over the three stages of disease in syntactic complexity, semantic and lexical content. The findings suggest, first, that there is a progressive disruption in language integrity, detectable from the prodromal stage in a subset of patients with Alzheimer’s disease, and secondly that measures of semantic and lexical content and syntactic complexity best capture the global progression of linguistic impairment through the successive clinical stages of disease. The identification of disease-specific language impairment in prodromal Alzheimer’s disease could enhance clinicians’ ability to distinguish probable Alzheimer’s disease from changes attributable to ageing, while longitudinal assessment could provide a simple approach to disease monitoring in therapeutic trials.
PMCID: PMC3859216  PMID: 24142144
Alzheimer’s disease; aphasia; neuropsychological tests; language; connected speech analysis
21.  The Alzheimer’s Prevention Initiative composite cognitive test score: Sample size estimates for the evaluation of preclinical Alzheimer’s disease treatments in presenilin 1 E280A mutation carriers 
There is a need to identify a cognitive composite that is sensitive to tracking preclinical AD decline to be used as a primary endpoint in treatment trials.
We capitalized on longitudinal data, collected from 1995 to 2010, from cognitively unimpaired presenilin 1 (PSEN1) E280A mutation carriers from the world’s largest known early-onset autosomal dominant AD (ADAD) kindred to identify a composite cognitive test with the greatest statistical power to track preclinical AD decline and estimate the number of carriers age 30 and older needed to detect a treatment effect in the Alzheimer’s Prevention Initiative’s (API) preclinical AD treatment trial. The mean-to-standard-deviation ratios (MSDRs) of change over time were calculated in a search for the optimal combination of one to seven cognitive tests/sub-tests drawn from the neuropsychological test battery in cognitively unimpaired mutation carriers during a two and five year follow-up period, using data from non-carriers during the same time period to correct for aging and practice effects. Combinations that performed well were then evaluated for robustness across follow-up years, occurrence of selected items within top performing combinations and representation of relevant cognitive domains.
This optimal test combination included CERAD Word List Recall, CERAD Boston Naming Test (high frequency items), MMSE Orientation to Time, CERAD Constructional Praxis and Ravens Progressive Matrices (Set A) with an MSDR of 1.62. This composite is more sensitive than using either the CERAD Word List Recall (MSDR=0.38) or the entire CERAD-Col battery (MSDR=0.76). A sample size of 75 cognitively normal PSEN1-E280A mutation carriers age 30 and older per treatment arm allows for a detectable treatment effect of 29% in a 60-month trial (80% power, p=0.05).
We have identified a composite cognitive test score representing multiple cognitive domains that has improved power compared to the most sensitive single test item to track preclinical AD decline in ADAD mutation carriers and evaluate preclinical AD treatments. This API composite cognitive test score will be used as the primary endpoint in the first API trial in cognitively unimpaired ADAD carriers within 15 years of their estimated age at clinical onset. We have independently confirmed our findings in a separate cohort of cognitively healthy older adults who progressed to the clinical stages of late-onset AD, described in a separate report, and continue to refine the composite in independent cohorts and compared with other analytical approaches.
PMCID: PMC4331113  PMID: 24816373
composite cognitive score; API; Alzheimer’s Prevention Initiative; E280A; PSEN1; presenilin1; sample size; preclinical; cognitively unimpaired; autosomal dominant; ADAD
22.  Event-related potential markers of brain changes in preclinical familial Alzheimer disease 
Neurology  2011;77(5):469-475.
Event-related potentials (ERPs) can reflect differences in brain electrophysiology underlying cognitive functions in brain disorders such as dementia and mild cognitive impairment. To identify individuals at risk for Alzheimer disease (AD) we used high-density ERPs to examine brain physiology in young presymptomatic individuals (average age 34.2 years) who carry the E280A mutation in the presenilin-1 (PSEN1) gene and will go on to develop AD around the age of 45.
Twenty-one subjects from a Colombian population with familial AD participated: 10 presymptomatic subjects positive for the PSEN1 mutation (carriers) and 11 siblings without the mutation (controls). Subjects performed a visual recognition memory test while 128-channel ERPs were recorded.
Despite identical behavioral performance, PSEN1 mutation carriers showed less positivity in frontal regions and more positivity in occipital regions, compared to controls. These differences were more pronounced during the 200–300 msec period. Discriminant analysis at this time interval showed promising sensitivity (72.7%) and specificity (81.8%) of the ERP measures to predict the presence of AD pathology.
Presymptomatic PSEN1 mutation carriers show changes in brain physiology that can be detected by high-density ERPs. The relative differences observed showing greater frontal positivity in controls and greater occipital positivity in carriers indicates that control subjects may use frontally mediated processes to distinguish between studied and unstudied visual items, whereas carriers appear to rely more upon perceptual details of the items to distinguish between them. These findings also demonstrate the potential usefulness of ERP brain correlates as preclinical markers of AD.
PMCID: PMC3146305  PMID: 21775732
23.  Clinical features and multidisciplinary approaches to dementia care 
Dementia is a clinical syndrome of widespread progressive deterioration of cognitive abilities and normal daily functioning. These cognitive and behavioral impairments pose considerable challenges to individuals with dementia, along with their family members and caregivers. Four primary dementia classifications have been defined according to clinical and research criteria: 1) Alzheimer’s disease; 2) vascular dementias; 3) frontotemporal dementias; and 4) dementia with Lewy bodies/Parkinson’s disease dementia. The cumulative efforts of multidisciplinary healthcare teams have advanced our understanding of dementia beyond basic descriptions, towards a more complete elucidation of risk factors, clinical symptoms, and neuropathological correlates. The characterization of disease subtypes has facilitated targeted management strategies, advanced treatments, and symptomatic care for individuals affected by dementia. This review briefly summarizes the current state of knowledge and directions of dementia research and clinical practice. We provide a description of the risk factors, clinical presentation, and differential diagnosis of dementia. A summary of multidisciplinary team approaches to dementia care is outlined, including management strategies for the treatment of cognitive impairments, functional deficits, and behavioral and psychological symptoms of dementia. The needs of individuals with dementia are extensive, often requiring care beyond traditional bounds of medical practice, including pharmacologic and non-pharmacologic management interventions. Finally, advanced research on the early prodromal phase of dementia is reviewed, with a focus on change-point models, trajectories of cognitive change, and threshold models of pathological burden. Future research goals are outlined, with a call to action for social policy initiatives that promote preventive lifestyle behaviors, and healthcare programs that will support the growing number of individuals affected by dementia.
PMCID: PMC3104685  PMID: 21655340
dementia; Alzheimer’s disease; clinical features; multidisciplinary care; BPSD; prodromal dementia
24.  Distinctive cognitive profiles in Alzheimer's disease and subcortical vascular dementia 
Background: There are inconsistencies in published reports regarding the profile of cognitive impairments in vascular dementia, and its differentiation from Alzheimer's disease.
Objectives: To identify the overall profile of cognitive impairment in subcortical vascular dementia as compared with Alzheimer's disease; and the tests which best discriminate between these groups.
Methods: 57 subjects participated: 19 with subcortical vascular dementia, 19 with Alzheimer's disease, and 19 controls. The dementia groups were matched for age, education, and general levels of cognitive and everyday functioning. Subcortical vascular dementia was defined by clinical features (prominent vascular risk factors plus a previous history of transient ischaemic events or focal neurological signs) and substantial white matter pathology on magnetic resonance imaging. All subjects were given a battery of 33 tests assessing episodic and semantic memory, executive/attentional functioning, and visuospatial and perceptual skills.
Results: Despite a minimal degree of overall dementia, both patient groups had impairments in all cognitive domains. The Alzheimer patients were more impaired than those with vascular dementia on episodic memory, while the patients with vascular dementia were more impaired on semantic memory, executive/attentional functioning, and visuospatial and perceptual skills. Logistic regression analyses showed that the two groups could be discriminated with 89% accuracy on the basis of two tests, the WAIS logical memory – delayed recall test and a silhouette naming test.
Conclusions: Subcortical vascular dementia and Alzheimer's disease produce distinctive profiles of cognitive impairment which can act as an adjunct to diagnosis. Many of the neuropsychological deficits thought to characterise Alzheimer's disease are also found in subcortical vascular dementia.
PMCID: PMC1757469  PMID: 14707310
25.  Epidemiological Pathology of Dementia: Attributable-Risks at Death in the Medical Research Council Cognitive Function and Ageing Study 
PLoS Medicine  2009;6(11):e1000180.
Researchers from the Medical Research Council Cognitive Function and Ageing Neuropathology Study carry out an analysis of brain pathologies contributing to dementia, within a cohort of elderly individuals in the UK who agreed to brain donation.
Dementia drug development aims to modulate pathological processes that cause clinical syndromes. Population data (epidemiological neuropathology) will help to model and predict the potential impact of such therapies on dementia burden in older people. Presently this can only be explored through post mortem findings. We report the attributable risks (ARs) for dementia at death for common age-related degenerative and vascular pathologies, and other factors, in the MRC Cognitive Function and Ageing Study (MRC CFAS).
Methods and Findings
A multicentre, prospective, longitudinal study of older people in the UK was linked to a brain donation programme. Neuropathology of 456 consecutive brain donations assessed degenerative and vascular pathologies. Logistic regression modelling, with bootstrapping and sensitivity analyses, was used to estimate AR at death for dementia for specific pathologies and other factors. The main contributors to AR at death for dementia in MRC CFAS were age (18%), small brain (12%), neocortical neuritic plaques (8%) and neurofibrillary tangles (11%), small vessel disease (12%), multiple vascular pathologies (9%), and hippocampal atrophy (10%). Other significant factors include cerebral amyloid angiopathy (7%) and Lewy bodies (3%).
Such AR estimates cannot be derived from the living population; rather they estimate the relative contribution of specific pathologies to dementia at death. We found that multiple pathologies determine the overall burden of dementia. The impact of therapy targeted to a specific pathology may be profound when the dementia is relatively “pure,” but may be less impressive for the majority with mixed disease, and in terms of the population. These data justify a range of strategies, and combination therapies, to combat the degenerative and vascular determinants of cognitive decline and dementia.
Please see later in the article for the Editors' Summary
Editors' Summary
Losing one's belongings and forgetting people's names is often a normal part of aging. But increasing forgetfulness can also be a sign of dementia, a group of symptoms caused by several disorders that affect the structure of the brain. The commonest form of dementia is Alzheimer disease. In this, protein clumps called plaques and neurofibrillary tangles form in the brain and cause its degeneration. Vascular dementia, in which problems with blood circulation deprive parts of the brain of oxygen, is also common. People with dementia have problems with two or more “cognitive” functions—thinking, language, memory, understanding, and judgment. As the disease progresses, they gradually lose their ability to deal with normal daily activities until they need total care, their personality often changes, and they may become agitated or aggressive. Dementia is rare before the age of 65 years but about a quarter of people over 85 years old have dementia. Because more people live to a ripe old age these days, the number of people with dementia is increasing. According to the latest estimates, about 35 million people now have dementia and by 2050, 115 million may have the disorder.
Why Was This Study Done?
There is no cure for dementia but many drugs designed to modulate specific abnormal (pathological) changes in the brain that can cause the symptoms of dementia are being developed. To assess the likely impact of these potentially expensive new therapies, experts need to know what proportion of dementia is associated with each type of brain pathology. Although some brain changes can be detected in living brains with techniques such as computed tomography brain scans, most brain changes can only be studied in brains taken from people after death (post mortem brains). In this study, which is part of the UK Medical Research Council Cognitive Function and Ageing Study (MRC CFAS), the researchers look for associations between dementia in elderly people and pathological changes in their post mortem brains and estimate the attributable-risk (AR) for dementia at death associated with specific pathological features in the brain. That is, they estimate the proportion of dementia directly attributable to each type of pathology.
What Did the Researchers Do and Find?
Nearly 20 years ago, the MRC CFAS interviewed more than 18,000 people aged 65 years or older recruited at six sites in England and Wales to determine their cognitive function and their ability to deal with daily activities. 20% of the participants, which included people with and without cognitive impairment, were then assessed in more detail and invited to donate their brains for post mortem examination. As of 2004, 456 individuals had donated their brains. The dementia status of these donors was established using data from their assessment interviews and death certificates, and from interviews with relatives and carers, and their brains were carefully examined for abnormal changes. The researchers then used statistical methods to estimate the AR for dementia at death associated with various abnormal brain changes. The main contributors to AR for dementia at death included age (18% of dementia at death was attributable to this factor), plaques (8%), and neurofibrillary tangles (11%) in a brain region called the neocortex, small blood vessel disease (12%), and multiple abnormal changes in blood vessels (9%).
What Do These Findings Mean?
These findings suggest that multiple abnormal brain changes determine the overall burden of dementia. Importantly, they also suggest that dementia is often associated with mixed pathological changes—many people with dementia had brain changes consistent with both Alzheimer disease and vascular dementia. Because people with dementia live for variable lengths of time during which the abnormal changes in their brain are likely to alter, it may be difficult to extrapolate these findings to living populations of elderly people. Furthermore, only a small percentage of the MRC CFAS participants have donated their brains so the findings of this study may not apply to the general population. Nevertheless, these findings suggest that the new therapies currently under development may do little to reduce the overall burden of dementia because most people's dementia involves multiple pathologies. Consequently, it may be necessary to develop a range of strategies and combination therapies to deal with the ongoing dementia epidemic.
Additional Information
Please access these Web sites via the online version of this summary at
The US National Institute on Aging provides information for patients and carers about forgetfulness and about Alzheimer disease (in English and Spanish)
The US National Institute of Neurological Disorders and Stroke provides information about dementia (in English and Spanish)
The UK National Health Service Choices Web site also provides detailed information for patients and their carers about dementia and about Alzheimer disease
MedlinePlus provides links to additional resources about dementia and Alzheimer disease (in English and Spanish)
More information about the UK Medical Research Council Cognitive Function and Ageing Study (MRC CFAS) is available
PMCID: PMC2765638  PMID: 19901977

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