PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-18 (18)
 

Clipboard (0)
None
Journals
Year of Publication
Document Types
1.  Comparison of imaging biomarkers in ADNI versus the Mayo Clinic Study of Aging 
Archives of neurology  2012;69(5):614-622.
Objective
To determine whether MRI measurements observed in the Alzheimer's Disease Neuroimaging Initiative (ADNI; convenience-sample) differ from those observed in the Mayo Clinic Study of Aging (MCSA; population-based sample).
Design
Comparison of two samples.
Setting
59 recruiting sites for the ADNI in US/Canada, and the MCSA, a population-based cohort in Olmsted County, MN.
Patients
Cognitively normal (CN) subjects and amnestic mild cognitive impairment (aMCI) subjects were selected from the ADNI convenience cohort and MCSA population-based cohort. Two samples were selected; the first was a simple random sample of subjects from both cohorts in the same age range, and the second applied matching for age, sex, education, apolipoprotein E genotype, and Mini-Mental State Examination.
Main outcome measures
Baseline hippocampal volumes and annual percent decline in hippocampal volume.
Results
In the population-based sample, MCSA subjects were older, less educated, performed worse on MMSE, and less often had family history of AD than ADNI subjects. Baseline hippocampal volumes were larger in ADNI compared to MCSA CN subjects in the random sample, although no differences were observed after matching. Rates of decline in hippocampal volume were greater in ADNI compared to MCSA for both CN and aMCI, even after matching.
Conclusions
Rates of decline in hippocampal volume suggest that ADNI subjects have more aggressive brain pathology than MCSA subjects, and hence may not be representative of the general population. These findings have implications for treatment trials that employ ADNI-like recruitment mechanisms and for studies validating new diagnostic criteria for AD in its various stages.
doi:10.1001/archneurol.2011.3029
PMCID: PMC3569033  PMID: 22782510
2.  Characterization of a Family With c9FTD/ALS Associated With the GGGGCC Repeat Expansion in C9ORF72 
Archives of neurology  2012;69(9):1164-1169.
Background
The hexanucleotide repeat in the chromosome 9 open reading frame 72 (C9ORF72) gene was recently discovered as the pathogenic mechanism underlying many families with frontotemporal dementia (FTD) and/or amyotrophic lateral sclerosis (ALS) linked to chromosome 9 (c9FTD/ALS). We report the clinical, neuropsychological, and neuroimaging findings of a family with the C9ORF72 mutation and clinical diagnoses bridging the FTD, parkinsonism and ALS spectrum.
Objective
To characterize the antemortem characteristics of a family with c9FTD/ALS associated with the GGGGCC repeat expansion in C9ORF72
Design
Clinical series.
Setting
Tertiary care academic medical center.
Patients
The members of the family affected by the mutation with features of FTD and/or ALS.
Main Outcome Measures
Clinical, neuropsychological, and neuroimaging assessments.
Results
All three examined subjects had the hexanucleotide expansion detected in C9ORF72. All had personality/behavioral changes early in the course of the disease. One case had levodopa-unresponsive parkinsonism, and one had ALS. MRI showed symmetric bilateral frontal, temporal, insular and cingulate atrophy.
Conclusions
This report highlights the clinical and neuroimaging characteristics of a family with c9FTD/ALS. Further studies are needed to better understand the phenotypical variability and the clinico-neuroimaging-neuropathologic correlations.
doi:10.1001/archneurol.2012.772
PMCID: PMC3625860  PMID: 22637471
3.  Shapes of the Trajectories of Five Major Biomarkers of Alzheimer’s Disease 
Archives of neurology  2012;69(7):856-867.
Objective
To characterize the shape of the trajectories of Alzheimer’s Disease (AD) biomarkers as a function of MMSE.
Design
Longitudinal registries from the Mayo Clinic and the Alzheimer’s Disease Neuroimaging Initiative (ADNI).
Patients
Two different samples (n=343 and n=598) were created that spanned the cognitive spectrum from normal to AD dementia. Subgroup analyses were performed in members of both cohorts (n=243 and n=328) who were amyloid positive at baseline.
Main Outcome Measures
The shape of biomarker trajectories as a function of MMSE, adjusted for age, was modeled and described as baseline (cross-sectional) and within-subject longitudinal effects. Biomarkers evaluated were cerebro spinal fluid (CSF) Aβ42 and tau; amyloid and fluoro deoxyglucose position emission tomography (PET) imaging, and structural magnetic resonance imaging (MRI).
Results
Baseline biomarker values generally worsened (i.e., non-zero slope) with lower baseline MMSE. Baseline hippocampal volume, amyloid PET and FDG PET values plateaued (i.e., non-linear slope) with lower MMSE in one or more analyses. Longitudinally, within-subject rates of biomarker change were associated with worsening MMSE. Non-constant within-subject rates (deceleration) of biomarker change were found in only one model.
Conclusions
Biomarker trajectory shapes by MMSE were complex and were affected by interactions with age and APOE status. Non-linearity was found in several baseline effects models. Non-constant within-subject rates of biomarker change were found in only one model, likely due to limited within-subject longitudinal follow up. Creating reliable models that describe the full trajectories of AD biomarkers will require significant additional longitudinal data in individual participants.
doi:10.1001/archneurol.2011.3405
PMCID: PMC3595157  PMID: 22409939
Alzheimer’s disease biomarkers; Magnetic Resonance Imaging; cerebro spinal fluid; amyloid PET imaging; FDG PET imaging
4.  Effect of APOE ε4 Status on Intrinsic Network Connectivity in Cognitively Normal Elderly 
Archives of Neurology  2011;68(9):1131-1136.
Objective
To examine default mode and salience network functional connectivity as a function of APOE ε4 status in a group of cognitively normal age, gender and education-matched older adults.
Design
Case-control study.
Setting
Community-based sample
Subjects
Fifty-six cognitively normal APOE ε4 carriers and 56 age, gender and education-matched cognitively normal APOE ε4 non-carriers.
Main Outcome Measure
Alterations in in-phase default mode and salience network connectivity in APOE ε4 carriers compared to APOE ε4 non-carriers ranging from 63 to 91 years of age.
Results
A posterior cingulate seed revealed decreased in-phase connectivity in regions of the posterior default mode network that included the left inferior parietal lobe, left middle temporal gyrus, and bilateral anterior temporal lobes in the ε4 carriers relative to APOE ε4 non-carriers. An anterior cingulate seed showed greater in-phase connectivity in the salience network, including the cingulate gyrus, medial prefrontal cortex, bilateral insular cortex, striatum, and thalamus in APOE ε4 carriers vs. non-carriers. There were no group-wise differences in brain anatomy.
Conclusions
We found reductions in posterior default mode network connectivity but increased salience network connectivity in elderly cognitively normal APOE ε4 carriers relative to APOE ε4 non-carriers at rest. The observation of functional alterations in connectivity in the absence of structural changes between APOE e4 carriers and non-carriers suggests that alterations in connectivity may have the potential to serve as an early biomarker.
doi:10.1001/archneurol.2011.108
PMCID: PMC3392960  PMID: 21555604
5.  Evidence for Ordering of Alzheimer’s Disease Biomarkers 
Archives of Neurology  2011;68(12):1526-1535.
Objective
To empirically assess the concept that Alzheimer’s disease (AD) biomarkers significantly depart from normality in a temporally ordered manner.
Design
Validation sample
Setting
Multi-site, referral centers
Patients
We studied 401 elderly cognitively normal (CN), Mild Cognitive Impairment (MCI) and AD dementia subjects from the Alzheimer’s Disease Neuroimaging Initiative. We compared the proportions of three AD biomarkers – CSF Aβ42, CSF total tau (t-tau), and hippocampal volume adjusted by intra-cranial volume (HVa) - that were abnormal as cognitive impairment worsened. Cut-points demarcating normal vs. abnormal for each biomarker were established by maximizing diagnostic accuracy in independent autopsy samples.
Interventions
None
Main Outcome measures
AD biomarkers
Results
Within each clinical group in the entire sample (n=401) CSF Aβ42 was abnormal more often than t-tau or HVa. Among the 298 subjects with both baseline and 12 month data, the proportion of subjects with abnormal Aβ42 did not change from baseline to 12 months in any group. The proportion of subjects with abnormal t-tau increased from baseline to 12 months in CN (p=0.05) but not in MCI or dementia. In 209 subjects with abnormal CSF AB42 at baseline, the percent abnormal HVa, but not t-tau, increased from baseline to 12 months in MCI.
Conclusions
Reduction in CSF Aβ42 denotes a pathophysiological process that significantly departs from normality (i.e., becomes dynamic) early, while t-tau and HVa are biomarkers of downstream pathophysiological processes. T-tau becomes dynamic before HVa, but HVa is more dynamic in the clinically symptomatic MCI and dementia phases of the disease than t-tau.
doi:10.1001/archneurol.2011.183
PMCID: PMC3387980  PMID: 21825215
Alzheimer’s disease biomarkers; Magnetic Resonance Imaging; CSF tau; CSF Abeta; Alzheimer’s disease staging
6.  Replication of CLU, CR1 and PICALM associations with Alzheimer’s disease 
Archives of neurology  2010;67(8):961-964.
Background
Harold et al. and Lambert et al. recently published two large genome-wide association studies of late onset Alzheimer’s disease (LOAD) in which CLU, CR1, and PICALM were identified as novel LOAD genes.
Objective
To test for replication of the association between variants in the CLU, CR1 and PICALM genes with Alzheimer’s disease.
Design
Case-control association study
Setting
Community-based ascertainment of patients seen at the Mayo Clinic Jacksonville, FL and Rochester, MN, and autopsy-confirmed cases and controls whose pathology was evaluated at the Mayo Clinic Jacksonville. Additional samples were obtained from the National Cell Repository for Alzheimer’s Disease (NCRAD).
Participants
LOAD case-control series of European descent consisting of 1,829 LOAD cases and 2,576 controls
Main Outcome Measure
Clinical or pathology-confirmed diagnosis of LOAD
Results
In our follow-up study of 1,829 LOAD cases and 2,576 controls, the most significant SNPs in CLU (rs11136000), CR1 (rs3818361), and PICALM (rs3851179) were tested for allelic association and gave ORs of 0.82, 1.15, and 0.80 respectively that were comparable in direction and magnitude to those originally reported with p values of 8.6×10−5, 0.014, and 1.3×10−5 that were significant even after Bonferroni correction for 3 SNPs tested.
Conclusion
These results showing near perfect replication provide the first additional evidence that CLU, CR1, and PICALM are LOAD genes.
doi:10.1001/archneurol.2010.147
PMCID: PMC2919638  PMID: 20554627
7.  Mild Cognitive Impairment: Ten Years Later 
Archives of neurology  2009;66(12):1447-1455.
In the past 10 years, there has been a virtual explosion in the literature concerning the construct of mild cognitive impairment. The interest in this topic demonstrates the increasing emphasis on the identification of the earliest features of cognitive disorders such as Alzheimer’s disease and other dementias. Mild cognitive impairment represents the earliest clinical features of these conditions and, hence, has become a focus of clinical, epidemiological, neuroimaging, biomarker, neuropathological, disease mechanism and clinical trials research. This review summarizes the progress that has been made while also recognizing the challenges that remain.
doi:10.1001/archneurol.2009.266
PMCID: PMC3081688  PMID: 20008648
Mild cognitive impairment; Alzheimer’s disease; Imaging; Cognitive decline
8.  Association of Prior Stroke with Cognitive Function and Cognitive Impairment: A Population-based Study 
Archives of neurology  2009;66(5):614-619.
Background
Defining the nature of the contribution of stroke to cognitive impairment remains challenging.
Methods
We randomly selected Olmsted County, MN residents aged 70–89 years on October 1, 2004 and invited eligible non-demented subjects to participate. Participants (n = 2,050) were evaluated with an informant interview, a neurological evaluation, and neuropsychological testing. Neuropsychological testing included 9 tests to assess memory, attention and executive function, visuospatial cognition and language. Subjects were diagnosed by consensus as cognitively normal, MCI (either amnestic (a-) or non-amnestic (na-)), or dementia. A history of stroke was obtained from the subject and confirmed in the medical record. We computed the odds ratios (OR) for a clinical diagnosis of MCI or for scoring in the lowest quartile on each cognitive domain.
Results
There were 1640 cognitively normal and 329 MCI subjects, 241 a-MCI and 88 na-MCI. In fully adjusted models with non-demented subjects only, a history of stroke was associated with a higher odds ratio (OR) of na-MCI (OR= 2.85, 95% CI 1.61 – 5.04) than a-MCI (OR= 1.77, 95% CI 1.14 – 2.74). A history of stroke was also associated with impaired function in each cognitive domain except memory. The association was strongest for attention and executive function (OR=2.48, 95% CI 1.73 – 3.53). APOE e4 genotype was associated only with a-MCI and with impaired memory function.
Conclusions
In this population-based sample of non-demented persons, a history of stroke was particularly associated with na-MCI and with impairment in non-memory cognition. APOE e4 genotype was associated with memory impairment and a-MCI.
doi:10.1001/archneurol.2009.30
PMCID: PMC3050015  PMID: 19433661
9.  Alzheimer's Disease-Like Phenotype Associated With the c.154delA Mutation in Progranulin 
Archives of neurology  2010;67(2):171-177.
Objective
To characterize a kindred with a familial neurodegenerative disorder associated with a mutation in progranulin (PGRN), emphasizing the unique clinical features in this kindred.
Design
Clinical, radiologic, pathologic, and genetic characterization of a kindred with a familial neurodegenerative disorder.
Setting
Multispecialty group academic medical center.
Patients
Affected members of a kindred with dementia +/- parkinsonism associated with a unique mutation in PGRN.
Main Outcome Measure
Genotype-phenotype correlation.
Results
Ten affected individuals were identified, among whom six presented with initial amnestic complaints resulting in initial diagnoses of AD or amnestic mild cognitive impairment (MCI). A minority of individuals presented with features characteristic of FTD. The ages of onset of generation II (mean 75.8 years, range 69-80 years) were far greater than those of generation III (mean 60.7 years, range 55-66 years). The pattern of cerebral atrophy varied widely among affected individuals. Neuropathology in six individuals showed frontotemporal lobar degeneration with ubiquitin positive neuronal cytoplasmic and intranuclear inclusions (FTLD-U + NII). PGRN analysis revealed a single base pair deletion in exon 2 (c.154delA), causing a frameshift (p.Thr52Hisfs×2) and therefore creation of a premature termination codon and likely null allele.
Conclusions
We describe a large kindred in which the majority of affected individuals had clinical presentations resembling AD or amnestic MCI in association with a mutation in PGRN and underlying FTLD-U + NII neuropathology. This is in distinct contrast to previously reported kindreds, where clinical presentations have typically been within the spectrum of FTLD. The basis for the large difference in age of onset between generations will require further study.
doi:10.1001/archneurol.2010.113
PMCID: PMC2902004  PMID: 20142525
MRI; progranulin; frontotemporal dementia; PGRN
10.  Functional Impact of White Matter Hyperintensities in Cognitively Normal Elderly 
Archives of neurology  2010;67(11):1379-1385.
Objective
To investigate the impact white matter hyperintensities (WMH) detected on MRI have on motor dysfunction and cognitive impairment in non-demented elderly subjects.
Design
Cross-sectional study.
Setting
Population-based study on the incidence and prevalence of cognitive impairment in Olmsted County, MN.
Participants
A total of 148 non-demented elderly (65 males) ranging in age from 73 to 91 years.
Main Outcome Measures
We measured the percentage of the total white matter volume classified as WMH (WMHp) in a priori defined brain regions (i.e. frontal, temporal, parietal, occipital, periventricular or subcortical). Motor impairment was evaluated qualitatively using the Unified Parkinson’s Disease Rating Scale (UPDRS) summary measures of motor skills and quantitatively using a digitized portable walkway system. Four cognitive domains were evaluated using z-scores of memory, language, executive function, and visuospatial reasoning.
Results
A higher WMHp in all regions except occipital was associated with lower executive function z-score (p-value<0.01). A higher WMHp in all regions, but most strongly for parietal lobe, correlated with higher gait/postural-stability/posture UPDRS sum (p-value<0.01). A higher WMHp whether periventricular, subcortical or lobar correlated with reduced velocity (p-value<0.001).
Conclusions
We conclude that executive function is the primary cognitive domain affected by WMH burden. The data suggests that WMH in the parietal lobe are chiefly responsible for reduced balance and postural support compared to the other three lobes and may alter integration of sensory information via parietal lobe dysfunction in the aging brain. It is of interest that parietal WM changes were not the predominant correlate with motor speed, lending evidence to a global involvement of neural networks in gait velocity.
doi:10.1001/archneurol.2010.280
PMCID: PMC3025610  PMID: 21060015
11.  Physical Exercise and Mild Cognitive Impairment: A Population-Based Study 
Archives of neurology  2010;67(1):80-86.
Objective
Physical exercise was found to be associated with a decreased risk of dementia and Alzheimer disease. We investigated whether physical exercise is also associated with mild cognitive impairment (MCI).
Design
Population-based case-control study.
Setting
The Mayo Clinic Study of Aging, an ongoing population-based cohort study in Olmsted County, Minnesota, USA.
Participants
1324 non-demented subjects who completed a questionnaire on physical exercise.
Main Outcome Measures
An expert consensus panel classified each subject as either cognitively normal or affected by MCI using information from a Clinical Dementia Rating Scale administered to the subject and to an informant, a neurological evaluation, and neuropsychological testing to assess 4 cognitive domains.
Results
We compared the frequency of physical exercise in 198 subjects with MCI to the frequency in 1126 cognitively normal subjects and adjusted analyses for age, sex, years of education, medical comorbidity, and depression. The odds ratio (OR) for any frequency of moderate-intensity exercise was 0.61 (95% confidence interval [CI], 0.43–0.88; P=.008) for exercise in midlife (aged 50–65 years), and 0.68 (95% CI, 0.49–0.93; P=.02) for exercise in late life. The findings were consistent in men and women. Light exercise and vigorous exercise were not significantly associated with MCI.
Conclusions
In this population-based case-control study, any frequency of moderate-intensity exercise carried out in either midlife or late life was associated with a reduced OR of MCI.
doi:10.1001/archneurol.2009.297
PMCID: PMC2919839  PMID: 20065133
12.  Survival Profiles of Patients With Frontotemporal Dementia and Motor Neuron Disease 
Archives of neurology  2009;66(11):1359-1364.
Background
Frontotemporal dementia and amyotrophic lateral sclerosis are neurodegenerative diseases associated with TAR DNA-binding protein 43– and ubiquitin-immunoreactive pathologic lesions.
Objective
To determine whether survival is influenced by symptom of onset in patients with frontotemporal dementia and amyotrophic lateral sclerosis.
Design, Setting, and Patients
Retrospective review of patients with both cognitive impairment and motor neuron disease consecutively evaluated at 4 academic medical centers in 2 countries.
Main Outcome Measures
Clinical phenotypes and survival patterns of patients.
Results
A total of 87 patients were identified, including 60 who developed cognitive symptoms first, 19 who developed motor symptoms first, and 8 who had simultaneous onset of cognitive and motor symptoms. Among the 59 deceased patients, we identified 2 distinct subgroups of patients according to survival. Long-term survivors had cognitive onset and delayed emergence of motor symptoms after a long monosymptomatic phase and had significantly longer survival than the typical survivors (mean, 67.5 months vs 28.2 months, respectively; P<.001). Typical survivors can have simultaneous or discrete onset of cognitive and motor symptoms, and the simultaneous-onset patients had shorter survival (mean, 19.2 months) than those with distinct cognitive or motor onset (mean, 28.6 months) (P=.005).
Conclusions
Distinct patterns of survival profiles exist in patients with frontotemporal dementia and motor neuron disease, and overall survival may depend on the relative timing of the emergence of secondary symptoms.
doi:10.1001/archneurol.2009.253
PMCID: PMC2881327  PMID: 19901167
13.  Rapidly Progressive Neurodegenerative Dementias 
Archives of neurology  2009;66(2):201-207.
Background
Neurodegenerative dementias are typically characterized by an insidious onset and a relatively slowly progressive course. Less common are patients with a rapidly progressive course to death.
Objective
To characterize patients with a neurodegenerative disease and a rapidly progressive course to death.
Setting
Tertiary Care Medical Center.
Design/Methods
Using a text word search for “rapid” and “dementia” in the same sentence, the Mayo Clinic Medical Records Linkage system was used to identify all patients evaluated between 1/1/00−9/30/07 with brain autopsy (N=96). Of these 96, we included only those with disease duration of <4 years to death and with histological diagnosis of a neurodegenerative disease.
Results
We identified 22 cases (10 males). Although 36% were Creutzfeldt-Jakob disease (CJD), the rest included frontotemporal lobar degenerative with motor neuron degeneration (FTLD-MND; 23%); a tauopathy (progressive supranuclear palsy or corticobasal degeneration; 18%); diffuse Lewy body disease (DLBD; 14%) or Alzheimer's disease 9%. All CJD cases died ≤12 months after onset while the others had illness duration of >12 months. Notably, all three DLBD patients, but no others, initially experienced a transient postoperative- or illness-associated encephalopathy, then relative normality for two years, before a rapidly progressive dementia and decline to death in 4−12 months.
Conclusions
Based on this cohort, although CJD is the most likely cause of a rapidly progressive neurodegenerative dementia, FTLD-MND, DLBD, tauopathies and Alzheimer's disease can also cause a rapidly progressive dementia. If illness duration is beyond 12-months, a non-CJD neurodegenerative disease may be more likely the diagnosis, than CJD.
doi:10.1001/archneurol.2008.534
PMCID: PMC2764283  PMID: 19204156
14.  Voxel-based morphometry in frontotemporal lobar degeneration with ubiquitin-positive inclusions with and without progranulin mutations 
Archives of neurology  2007;64(3):371-376.
Background
Mutations in the progranulin gene (PGRN) have recently been identified as a cause of frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) in some families.
Objective
To determine whether there is a difference in the patterns of atrophy in cases with FTLD-U with and without a mutation in PGRN.
Design
Case control study
Setting
Brain bank of a tertiary care medical center
Patients
All subjects that had screened positive for mutations in PGRN and had a volumetric MRI were identified (n=8, PGRN (+)). Subjects were then matched by clinical diagnosis to a group of eight subjects with a pathological diagnosis of FTLD-U that had screened negative for mutations in PGRN (PGRN (−)). All subjects were then age and gender-matched to a control subject.
Main outcome Measures
Voxel-based morphometry was used to assess the patterns of grey matter atrophy in the PGRN (+) and (−) groups compared to controls, and compared to each other.
Results
The PGRN (+) group showed a widespread and severe pattern of grey matter loss predominantly affecting the frontal, temporal and parietal lobes. In comparison, the PGRN (−) group showed a less severe pattern of loss restricted mainly to the temporal and frontal lobes. On direct comparison the PGRN (+) group showed greater loss in the frontal and parietal lobes compared to the PGRN (−) group.
Conclusions
This study suggests that PGRN mutations may be associated with a specific and severe pattern of cerebral atrophy in subjects with FTLD-U.
doi:10.1001/archneur.64.3.371
PMCID: PMC2752412  PMID: 17353379
Frontotemporal dementia; Voxel-based morphometry; Ubiquitin; Dentate; Progranulin
15.  Visual Hallucinations in Posterior Cortical Atrophy 
Archives of neurology  2006;63(10):1427-1432.
Objective
To compare clinical and imaging features of patients with posterior cortical atrophy (PCA) with and without well-formed visual hallucinations.
Setting
Tertiary care medical center
Methods
Fifty-nine patients fulfilling criteria for PCA were retrospectively identified, and divided into two groups based on the presence (N=13) and absence (N=46) of visual hallucinations. Both groups were then compared statistically for clinical differences, as well as with voxel-based morphometry (VBM) for imaging differences.
Results
In PCA patients with hallucinations, parkinsonism and rapid eye movement sleep behavior disorder occurred more frequently (p<0.0001), as did myoclonic jerks (p=0.0002). VBM analysis showed greater atrophy in a network of structures, including the primary visual cortex, lentiform nuclei, thalamus, basal forebrain and midbrain in the patients with hallucinations.
Conclusions
Hallucinations in patients with PCA are associated with parkinsonism, rapid eye movement sleep behavior disorder, and myoclonic jerks. The results from the VBM analysis suggest that hallucinations in PCA cannot be exclusively attributed to atrophy of the posterior association cortices and may involve a circuit of thalamocortical connections.
doi:10.1001/archneur.63.10.1427
PMCID: PMC2748870  PMID: 17030659
Parkinsonism; Thalamus; Myoclonic jerks; REM sleep; Voxel based morphometry
16.  Hippocampal Volumes, Proton Magnetic Resonance Spectroscopy Metabolites, and Cerebrovascular Disease in Mild Cognitive Impairment Subtypes 
Archives of neurology  2008;65(12):1621-1628.
Background
Although a majority of patients with amnestic mild cognitive impairment (aMCI) progress to Alzheimer disease, the natural history of nonamnestic MCI (naMCI) is less clear. Noninvasive imaging surrogates for underlying pathological findings in MCI would be clinically useful for identifying patients who may benefit from disease-specific treatments at the prodromal stage of dementia.
Objective
To determine the characteristic magnetic resonance imaging (MRI) and proton MR spectroscopy (1H MRS) profiles of MCI subtypes.
Design
Case-control study.
Setting
Community-based sample at a tertiary referral center.
Patients
Ninety-one patients with single-domain aMCI, 32 patients with multiple-domain aMCI, 20 patients with single- or multiple-domain naMCI, and 100 cognitively normal elderly subjects frequency-matched by age and sex.
Main Outcome Measures
Posterior cingulate gyrus 1H MRS metabolite ratios, hippocampal volumes, and cerebrovascular disease on MRI.
Results
Patients with single-domain aMCI were characterized by small hippocampal volumes and elevated ratios of myo-inositol to creatine levels. Patients with naMCI on average had normal hippocampal volumes and 1H MRS metabolite ratios, but a greater proportion (3 of 20 patients [15%]) had cortical infarctions compared with patients with single-domain aMCI (6 of 91 [7%]). For characterization of MCI subtypes, 1H MRS and structural MRI findings were complementary.
Conclusions
The MRI and 1H MRS findings in singledomain aMCI are consistent with a pattern similar to that of Alzheimer disease. Absence of this pattern on average in patients with naMCI suggests that cerebrovascular disease and other neurodegenerative diseases may be contributing to the cognitive impairment in many individuals with naMCI.
doi:10.1001/archneur.65.12.1621
PMCID: PMC2743393  PMID: 19064749
17.  Detecting Dementia with the Mini-Mental State Examination (MMSE) in Highly Educated Individuals 
Archives of neurology  2008;65(7):963-967.
Objectives
To evaluate the utility of Mini-Mental State Examination (MMSE) scores in detecting cognitive dysfunction in a sample of highly educated individuals.
Design
Archival data were reviewed on 4248 participants enrolled in the Mayo Clinic Alzheimer's Disease Research Center (ADRC) and Alzheimer's Disease Patient Registry (ADPR).
Patients
1141 primarily Caucasian (93%) individuals with 16 or more years of self-reported education were identified. These included 307 (164 males and 143 females) dementia cases (any type), 176 patients with Mild Cognitive Impairment (106 males and 70 females), and 658 nondemented controls (242 males and 416 females).
Setting
Mayo Clinic ADRC and ADPR cohort.
Main Outcome Measures
Diagnostic accuracy estimates (sensitivity, specificity, positive and negative predictive power) of MMSE cut-scores in detecting cognitive dysfunction.
Results
In this sample of highly educated, largely Caucasian older adults, the standard MMSE cut-score of 24 (23 or below) yielded a sensitivity of .66, specificity of .99 and an overall correct classification rate of 89% in detecting dementia. A cut score to 27 (26 or below) resulted in an optimal balance of sensitivity and specificity (.89 and .91, respectively) with an overall correct classification rate of 90%. In a cognitively impaired group (dementia and MCI), a cut-score of 27 (sensitivity = .69, specificity = .91) or 28 (sensitivity and specificity = .78) might be more appropriate.
Conclusion
Elderly patients with college education who present with complaints of cognitive decline (self- or other-report) and score below 27 on the MMSE are at greater risk of being diagnosed with dementia and should be referred for a comprehensive dementia evaluation, including formal neuropsychological testing.
doi:10.1001/archneur.65.7.963
PMCID: PMC2587038  PMID: 18625866
Alzheimer's disease; dementia; Mini-Mental State Examination; diagnosis
18.  Duration and Severity of Diabetes Are Associated with Mild Cognitive Impairment 
Archives of neurology  2008;65(8):1066-1073.
Background
It remains unknown whether diabetes mellitus is a risk factor for mild cognitive impairment (MCI).
Objective
To investigate the association of diabetes mellitus with MCI using a population-based case-control design.
Design, Setting, and Participants
Our study was conducted in subjects aged 70 through 89 years on October 1, 2004, who were randomly selected from the Olmsted County, MN, population.
Main Outcome Measure
We administered to all participants the Clinical Dementia Rating Scale, a neurological exam, and a neuropsychological evaluation including 9 tests in 4 cognitive domains to diagnose normal cognition, MCI, or dementia. We assessed history of diabetes, diabetes treatment, and complications by interview and we measured fasting blood glucose. History of diabetes was also confirmed using a medical records-linkage system.
Results
We compared 329 patients with MCI to 1640 subjects free of MCI and of dementia. The frequency of diabetes was similar in subjects with MCI (20.1%) and in subjects without MCI (17.7%; odds ratio [OR], 1.16; 95% confidence interval [CI], 0.85-1.57). However, MCI was associated with onset of diabetes before age 65 years (OR, 2.20; 95% CI, 1.29-3.73), diabetes duration ≥10 years (OR, 1.76; 95% CI, 1.16-2.68), treatment with insulin (OR, 2.01; 95% CI, 1.22-3.31), and presence of complications (OR, 1.80; 95% CI, 1.13-2.89) after adjustment for age, sex, and education. Analyses using alternative definitions of diabetes yielded consistent findings.
Conclusions
These findings suggest an association between earlier onset, longer duration, and greater severity of diabetes and MCI.
doi:10.1001/archneur.65.8.1066
PMCID: PMC2630223  PMID: 18695056

Results 1-18 (18)