Background. Features that may allow early identification of patients at risk of prolonged delirium, and therefore of poorer outcomes, are not well understood. The aim of this study was to determine if preoperative delirium risk factors and delirium symptoms (at onset and clinical symptomatology during the course of delirium) are associated with delirium duration. Methods. This study was conducted in prospectively identified cases of incident delirium. We compared patients experiencing delirium of short duration (1 or 2 days) with patients who had more prolonged delirium (≥3 days) with regard to DRS-R-98 (Delirium Rating Scale Revised-98) symptoms on the first delirious day. Delirium symptom profile was evaluated daily during the delirium course. Results. In a homogenous population of 51 elderly hip-surgery patients, we found that the severity of individual delirium symptoms on the first day of delirium was not associated with duration of delirium. Preexisting cognitive decline was associated with prolonged delirium. Longitudinal analysis using the generalised estimating equations method (GEE) identified that more severe impairment of long-term memory across the whole delirium episode was associated with longer duration of delirium. Conclusion. Preexisting cognitive decline rather than severity of individual delirium symptoms at onset is strongly associated with delirium duration.
Delirium is a prevalent problem in long-term care (LTC) facilities where advanced age and cognitive impairment represent two important risk factors for this condition. Delirium is associated with numerous negative outcomes including increased morbidity and mortality. Despite its clinical importance, delirium often goes unrecognized by nurses. Although rates of nurse-detected delirium have been studied among hospitalized older patients, this issue has been largely neglected among demented older residents in LTC settings. The goals of this study were to determine detection rates of delirium and delirium symptoms by nurses among elderly residents with dementia and to identify factors associated with undetected cases of delirium.
In this prospective study (N = 156), nurse ratings of delirium were compared to researcher ratings of delirium. This procedure was repeated for 6 delirium symptoms. Sensitivity, specificity, positive and negative predictive values were computed. Logistic regressions were conducted to identify factors associated with delirium that is undetected by nurses.
Despite a high prevalence of delirium in this cohort (71.5%), nurses were able to detect the delirium in only a minority of cases (13%). Of the 134 residents not identified by nurses as having delirium, only 29.9% of them were correctly classified. Detection rates for the 6 delirium symptoms varied between 39.1% and 58.1%, indicating an overall under-recognition of symptoms of delirium. Only the age of the residents (≥ 85 yrs) was associated with undetected delirium (OR: 4.1; 90% CI: [1.5–11.0]).
Detection of delirium is a major issue for nurses that clearly needs to be addressed. Strategies to improve recognition of delirium could result in a reduction of adverse outcomes for this very vulnerable population.
S100B protein and Neuron Specific Enolase (NSE) can increase due to brain cell damage and/or increased permeability of the blood-brain-barrier. Elevation of these proteins has been shown after various neurological diseases with cognitive dysfunction. Delirium is characterized by temporal cognitive deficits and is an important risk factor for dementia. The aim of this study was to compare the level of S100B and NSE of patients before, during and after delirium with patients without delirium and investigate the possible associations with different subtypes of delirium.
The study population were patients aged 65 years or more acutely admitted after hip fracture. Delirium was diagnosed by the Confusion Assessment Method and the subtype by Delirium Symptom interview. In maximal four serum samples per patient S100B and NSE levels were determined by electrochemiluminescence immunoassay.
Of 120 included patients with mean age 83.9 years, 62 experienced delirium. Delirious patients had more frequently pre-existing cognitive impairment (67% vs. 18%, p < 0.001). Comparing the first samples during delirium to samples of non-delirious patients, a difference was observed in S100B (median 0.16 versus 0.10 μg/L, p = < 0.001), but not in NSE (median 11.7 versus 11.7 ng/L, p = 0.97). Delirious state (before, during, after) (p < 0.001), day of blood withdrawal (p < 0.001), pre- or postoperative status (p = 0.001) and type of fracture (p = 0.036) were all associated with S100B level. The highest S100B levels were found 'during' delirium. S100B levels 'before' and 'after' delirium were still higher than those from 'non-delirious' patients. No significant difference in S100B (p = 0.43) or NSE levels (p = 0.41) was seen between the hyperactive, hypoactive and mixed subtype of delirium.
Delirium was associated with increased level of S100B which could indicate cerebral damage either due to delirium or leading to delirium. The possible association between higher levels of S100B during delirium and the higher risk of developing dementia after delirium is an interesting field for future research. More studies are needed to elucidate the role of S100B proteins in the pathophysiological pathway leading to delirium and to investigate its possibility as biomarker for delirium.
Delirium is a disorder of acute onset with fluctuating symptoms and is characterized by inattention, disorganized thinking, and altered levels of consciousness. The risk for delirium is greatest in individuals with dementia, and the incidence of both is increasing worldwide because of the aging of our population. Although several clinical trials have tested interventions for delirium prevention in individuals without dementia, little is known about the mechanisms for the prevention of delirium in early-stage Alzheimer’s disease (AD). The purpose of this article is to explore ways of preventing delirium and slowing the rate of cognitive decline in early-stage AD by enhancing cognitive reserve. An agenda for future research on interventions to prevent delirium in individuals with early-stage AD is also presented.
Cognitive decline is commonly stated as one of the main risk
factors for delirium. The aim was to assess the importance of a
delirium episode as a symptom of an underlying dementia among community
dwelling healthy elderly people in a prospective 2 year follow up
study. The study patients consisted of 51 people living at home and
older than 65 years of age, without severe underlying disorders
including diagnosed dementia, admitted consecutively as emergency cases
to hospital because of an acute delirious state and followed up for 2 years. The diagnosis of delirium and dementia were based on the
DSM-III-R criteria. The community dwelling patients were evaluated and
tested annually by a clinical investigator, a geriatric study nurse,
and a neuropsychologist. The medical records of the institutionalised
patients were also evaluated. Dementia was diagnosed immediately after
the assurance that delirium symptoms had subsided in 14 out of 51 subjects (27%) and the additional 14 subjects were diagnosed as being
demented during the 2 year follow up, 28 out of 51 patients
(55%) altogether. Alzheimer's disease or mixed dementia was diagnosed
in 14 out of 51 patients (27%), vascular dementia in 10 (20%), and
dementia with Lewy bodies in two (4%). One case of alcoholic dementia
and one case of a non-alcoholic hepatic encephalopathia were also
found. A delirium episode is often the first sign of dementia requiring
attention from medical and social professionals.
Delirium is common in persons with dementia and often accompanies acute medical or surgical conditions. These individuals are at risk for an accelerated decline in their cognitive and physical function. For this reason, interventions that help resolve delirium are critically needed. We have developed a non-pharmacological intervention for delirium in persons with dementia based on our prior interdisciplinary work on delirium, dementia and cognitive stimulation. The intervention uses recreational activities that are alerting, capture attention, and provide cognitive stimulation that encourages cognitive processing in support of cognitive function. In this paper we describe the practical protocol we have developed for implementing these activities, and present a video that will enhance treatment fidelity for studies that replicate the approach.
Cognitive stimulation; recreational activities; delirium; dementia
Delirium in older hospital inpatients appears to be associated with various adverse outcomes. The limitations of previous research on this association have included small sample sizes, short follow-up periods and lack of consideration of important confounders or modifiers, such as severity of illness, comorbidity and dementia. The objective of this study was to determine the prognostic significance of delirium, with or without dementia, for cognitive and functional status during the 12 months after hospital admission, independent of premorbid function, comorbidity, severity of illness and other potentially confounding variables.
Patients 65 years of age and older who were admitted from the emergency department to the medical services were screened for delirium during their first week in hospital. Two cohorts were enrolled: patients with prevalent or incident delirium and patients without delirium, but similar in age and cognitive impairment. The patients were followed up at 2, 6 and 12 months after hospital admission. Analyses were conducted for 4 patient groups: 56 with delirium, 53 with dementia, 164 with both conditions and 42 with neither. Baseline measures included delirium (Confusion Assessment Method), dementia (Informant Questionnaire on Cognitive Decline in the Elderly), physical function (Barthel Index [BI] and premorbid instrumental activities of daily living, IADL), the Mini-Mental State Examination (MMSE), comorbidity, and physiologic and clinical severity of illness. Outcome variables measured at follow-up were the MMSE, Barthel Index, IADL and admission to a long-term care facility.
After adjustment for covariates, the mean differences in MMSE scores at follow-up between patients with and without delirium were –4.99 (95% confidence interval [CI] –7.17 to –2.81) for patients with dementia and –3.36 (95% CI –6.15 to –0.58) for those without dementia. At 12 months, the adjusted mean differences in the BI were –16.45 (95% CI –27.42 to –5.50) and –13.89 (95% CI –28.39 to 0.61) for patients with and without dementia respectively. Patients with both delirium and dementia were more likely to be admitted to long-term care than those with neither condition (adjusted odds ratio 3.18, 95% CI 1.19 to 8.49). Dementia but not delirium predicted worse IADL scores at follow-up. Unadjusted analyses yielded similar results.
For older patients with and without dementia, delirium is an independent predictor of sustained poor cognitive and functional status during the year after a medical admission to hospital.
Delirium or acute brain dysfunction is extremely prevalent in medical intensive care unit (ICU) patients, but limited data exist regarding its prevalence and risk factors among surgical (SICU) and trauma ICU (TICU) patients. The purpose of this study was to determine the prevalence and risk factors for delirium in surgical and trauma ICU patients.
SICU and TICU patients requiring mechanical ventilation (MV) >24 hours were prospectively evaluated for delirium using the Richmond Agitation Sedation Scale (RASS) and the Confusion Assessment Method for the ICU (CAM-ICU). Those with baseline dementia, intracranial injury, or ischemic/hemorrhagic strokes that would confound the evaluation of delirium were excluded. Markov models were used to determine predictors for daily transition to delirium.
One-hundred patients (46 SICU and 54 TICU) were enrolled. Prevalence of delirium was 73% in the SICU and 67% in the TICU. Multivariable analyses identified midazolam [OR 2.75 (CI 1.43–5.26, p = 0.002)] exposure as the strongest independent risk factor for transitioning to delirium. Opiate exposure showed an inconsistent message such that fentanyl was a risk factor for delirium in the SICU (p = 0.007) but not in the TICU (p = 0.936), while morphine exposure was associated with a lower risk of delirium (SICU, p = 0.069; TICU p = 0.024).
Approximately 7 out of 10 SICU and TICU patients experience delirium. In keeping with other recent data on benzodiazepines, exposure to midazolam is an independent and potentially modifiable risk factor for the transitioning to delirium.
trauma; surgery; cognitive impairment; delirium; mechanical ventilation; critical care; sedatives and analgesic
Delirium is a frequent complication in medically ill elderly patients that is associated with serious adverse outcomes including increased mortality. Delirium risk is linked to older age, dementia, and illness that involves activation of inflammatory responses. IGF-I is increasingly postulated as a key link between environmental influences on body metabolism with a range of neuronal activities and has been described as the master regulator of the connection between brain and bodily well-being. The relationships between IGF-I and ageing, cognitive impairment and inflammatory illness further support a possible role in delirium pathogenesis. Five studies of IGF-I in delirium were identified by a systematic review. These conflicting findings, with three of the five studies indicating an association between IGF-1 and delirium occurrence, may relate to the considerable methodological differences in these studies. The relevance of IGF-I and related factors to delirium pathogenesis can be clarified by future studies which account for these issues and other confounding factors. Such work can inform therapeutic trials of IGF-I and/or growth hormone administration.
There is a high prevalence of delirium in older medical intensive care unit (ICU) patients and delirium is associated with adverse outcomes. We need to identify modifiable risk factors for delirium in the ICU, such as medication use. The objective of this study was to examine the impact of benzodiazepine or opioid use on the duration of ICU delirium in an older medical population.
Prospective cohort study.
Fourteen-bed medical intensive care unit in an urban university teaching hospital.
304 consecutive admissions age 60 and older.
Main Outcome Measurements
The main outcome measure was duration of ICU delirium, specifically the first episode of ICU delirium. Patients were assessed daily for delirium with the Confusion Assessment Method for the ICU (CAM-ICU) and a validated chart review method. Our main predictor was the receipt of benzodiazepines or opioids during ICU stay. A multivariable model was developed using Poisson rate regression.
Delirium occurred in 239 of 304 patients (79%). The median duration of ICU delirium was 3 days with a range of 1-33 days. In a multivariable regression model receipt of a benzodiazepine or opioid (RR, 1.64, 95% CI, 1.27-2.10) was associated with increased delirium duration. Other variables associated with delirium duration in this analysis include preexisting dementia (RR, 1.19, 95% CI 1.07-1.33), receipt of haloperidol (RR, 1.35, 95% CI, 1.21-1.50), and severity of illness (RR, 1.01, 95% CI, 1.00-1.02).
The use of benzodiazepines or opioids in the ICU is associated with longer duration of a first episode of delirium. Receipt of these medications may represent modifiable risk factors for delirium. Clinicians caring for ICU patients should carefully evaluate the need for benzodiazepines, opioids and haloperidol.
delirium; critical care; risk factors; aged; benzodiazepines; opioids; haloperidol
Postoperative delirium is associated with increased morbidity and mortality. Pre-existing cognitive impairment and depression have been frequently cited as important risk factors for this complication. This prospective cohort study was designed to determine if individuals who perform poorly on preoperative cognitive tests and/or exhibited depressive symptoms would be at high risk for the development of postoperative delirium.
One hundred nondemented patients, 50 years and older, scheduled for major, elective noncardiac surgery completed a preoperative test battery that included measures of global cognition, executive function and symptoms of depression. Known preoperative risk factors for delirium were collected and examined with the results of the preoperative test battery to determine the independent predictors of delirium.
The overall incidence of delirium was 16% and was associated with increased hospital length of stay (p<0.05) and an increased incidence of postoperative complications (p<0.01). Delirious subjects did not differ from their non-delirious cohorts with regard to their preoperative global cognitive function, preexisting medical comorbidities, age, anesthetic management or history of alcohol use. Preoperative executive scores (p<0.001) and depression (p<0.001), as measured by the Trail Making B test and Geriatric Depression Scale Short Form, respectively, were found to be independent predictors of postoperative delirium.
Low preoperative executive scores and depressive symptoms independently predict postoperative delirium in older individuals. A rapid, simple test combination including tests of executive function and depression could improve physicians’ ability to recognize patients who might benefit from a perioperative intervention strategy to prevent postoperative delirium.
Leptin is a hormone with significant effects on the brain, both at the cellular level and cognitive level. This study aimed to establish the association between leptin levels and delirium in a Colombian elderly population. 115 patients older than 60 years were included. Leptin was measured by enzyme-linked immunosorbent assay after overnight fasting and Mini-Mental State Examination and Confusion Assessment Method (CAM) tests were employed. Delirium was diagnosed using CAM in 23.48% of patients, being most frequent in men. There were no significant differences in hematology and renal test values between patients with delirium and those without delirium, but cerebrovascular diagnoses were more frequent in patients with delirium. No correlation with any specific medication was found, but patients with delirium had a higher number of comorbidities and medications. Leptin levels were significantly lower in patients with delirium and correlated negatively with the number of diagnoses and medications, but not with age, gender, body mass index, or hematology and renal test results. Leptin levels may have a role in the pathophysiological process of delirium and low leptin could be a useful clinical biomarker to establish risk in elderly patients given the association with delirium.
delirium; elderly; hospitalization; leptin
The present study was carried out on the hospitalized geriatric general medical patients with the aim to identify the possible risk factors associated with delirium in the elderly. The assessment of the patients was carried out using Mini Mental Status Examination (MMSE), Delirium Symptom Interview (DSI), Delirium Rating Scale (DRS) and ICD-10 Diagnostic Criteria for Research for delirium Details of medical records were collected. An overall rate of delirium of 27% was found in the 100 patients who constituted the sample. Pre-existing cognitive deficits, neurological illnesses, urinary tract infections, visual impairment, hearing impairment, current proteinuria, leukocytosis, raised blood ammonia, hyponatremia and potassium level disturbances were the risk factors identified.
Delirium; elderly; genatric; risk factor
The oldest-old are the fastest growing segment of the Western population. Over half of the oldest-old will have dementia, but the etiology is yet unknown. Age is the only risk factor consistently associated with dementia in the oldest-old. Many of the risk and protective factors for dementia in the young elderly, such as ApoE genotype, physical activity, and healthy lifestyle, are not relevant for the oldest-old. Neuropathology is abundant in the oldest-old brains, but specific pathologies of Alzheimer’s disease (AD) or vascular dementia are not necessarily correlated with cognition, as in younger persons. It has been suggested that accumulation of both AD-like and vascular pathologies, loss of synaptic proteins, and neuronal loss contribute to the cognitive decline observed in the oldest-old. Several characteristics of the oldest-old may confound the diagnosis of dementia in this age group. A gradual age-related cognitive decline, particularly in executive function and mental speed, is evident even in non-demented oldest-old. Hearing and vision losses, which are also prevalent in the oldest-old and found in some cases to precede/predict cognitive decline, may mechanically interfere in neuropsychological evaluations. Difficulties in carrying out everyday activities, observed in the majority of the oldest-old, may be the result of motor or physical dysfunction and of neurodegenerative processes. The oldest-old appear to be a select population, who escapes major illnesses or delays their onset and duration toward the end of life. Dementia in the oldest-old may be manifested when a substantial amount of pathology is accumulated, or with a composition of a variety of pathologies. Investigating the clinical and pathological features of dementia in the oldest-old is of great importance in order to develop therapeutic strategies and to provide the most elderly of our population with good quality of life.
Dementia; epidemiology; neurobiology; oldest-old; risk factors
To review the mechanisms of sedative-hypnotic action with respect to the risk of delirium imparted by drugs that act on γ-amino-butyric-acid type A receptors or α2 adrenoceptors.
MEDLINE was searched for relevant articles.
Development of the acute confusional state of delirium is associated with longer intensive care unit (ICU) and hospital lengths of stay, significantly higher risk of functional decline, and increased mortality. Disruption of sleep is a modifiable risk factor that may contribute to delirium and cognitive dysfunction in ICU patients. Among the functions of sleep are repair of defective processes and restoration of the brain to a state in which it is ready to acquire new knowledge. It is logical that disruption of these processes may produce acute confusion. Delirium develops through a complex interaction between the patient’s baseline vulnerability (patient’s predisposing risk factors before hospitalization) and precipitating factors or insults (modifiable events that occur during hospitalization). The latter factors include both sleep disruption and sedation. We present a hypothesis that these two factors are causally linked through effects on memory. Our hypothesis explains why patients randomized to receive an α2 adrenoceptor agonist are less likely to develop delirium (and the attendant cognitive dysfunction) than those randomized to receive benzodiazepines.
Herein we present our hypothesis that alternate mechanisms of hypnotic action may differentiate the deleriogenic properties of the two classes of sedatives. Future studies should focus on whether a causal relationship can be established between sedative administration, sleep disruption, and delirium.
Hip fractures mainly affect older people. It is associated with high morbidity and mortality, and in particular a high frequency of delirium. Incident delirium following hip fracture is associated with an increased risk of dementia in the following months, but it is still not firmly established whether this is an association or a causal relationship. Orthogeriatric units vary with respect to content and timing of the intervention. One main effect of orthogeriatric care may be the prevention of delirium, especially if preoperative and postoperative care are provided. Thus, the aim of Oslo Orthogeriatric Trial, is to assess whether combined preoperative and postoperative orthogeriatric care can reduce the incidence of delirium and improve cognition following hip fracture.
Inclusion and randomisation will take place in the Emergency Department, as soon as possible after admission. All patients with proximal femur fractures are eligible, irrespective of age, pre-fracture function and accommodation, except if the fracture is caused by a high energy trauma or the patient is terminally ill. The intervention is pre-and post-operative orthogeriatric care delivered on a dedicated acute geriatric ward. The primary outcome measure is a composite endpoint combining the Clinical Dementia Rating Scale (CDR) and the 10 word memory task at four months after surgery. Secondary outcomes comprise incident delirium, length of stay, cognition, mobility, place of residence, activities of daily living and mortality, measured at 4 and 12 months after surgery. We have included 332 patients in the period 17th September 2009 to 5th January 2012.
Our choice of outcome measures and our emphasis of orthogeriatric care in the preoperative as well as the postoperative phase will enable us to provide new knowledge on the impact of orthogeriatric care on cognition.
Delirium is a common outcome after cardiac surgery. Delirium prediction rules identify patients at risk for delirium who may benefit from targeted prevention strategies, early identification and treatment of underlying causes. The purpose of this prospective study was to develop a prediction rule for delirium in a cardiac surgery cohort and validate it in an independent cohort.
Methods and Results
Prospectively, cardiac surgery patients ≥60 years were enrolled in a derivation sample (n=122) and then a validation sample (n=109). Beginning on the second postoperative day, patients underwent a standardized daily delirium assessment and delirium was diagnosed according to the Confusion Assessment Method. Delirium occurred in 63 (52%) of the derivation cohort patients. Multivariable analysis identified four variables independently associated with delirium: prior stroke or transient ischemic attack (TIA), Mini Mental State Examination (MMSE) score, abnormal serum albumin, and the Geriatric Depression Scale (GDS). Points were assigned to each variable: MMSE ≤23 received 2 points; MMSE 24-27, GDS >4, prior stroke/TIA, and abnormal albumin received 1 point each. In the derivation sample, the cumulative incidence of delirium for point levels of 0, 1, 2, and ≥3 was 19%, 47%, 63%, and 86%, respectively (C-statistic 0.74). The corresponding incidence of delirium in the validation sample was 18%, 43%, 60%, and 87%, respectively (C-statistic 0.75).
Delirium occurs frequently after cardiac surgery. Using four preoperative characteristics, clinicians can determine cardiac surgery patients' risk for delirium. Patients at higher delirium risk could be candidates for close postoperative monitoring and interventions to prevent delirium.
Delirium; Cardiac surgery; aged; cognition; prediction rule; depression
Delirium remains a significant risk for hospitalized older adults and has been shown to be a persistent risk posthospitalization as well. Dementia is a risk factor for delirium. The prevalence of delirium superimposed on dementia (DSD) ranges from 22% to 89% in hospitalized and community-dwelling individuals 65 and older. Individuals with DSD have been found to have accelerated decline in cognitive and functional abilities, greater need for institutionalization, greater rehospitalization risk, and increased mortality. The purpose of this article is to define and describe DSD, outline assessment tools for its identification, and provide appropriate nursing interventions.
Postoperative delirium, a common complication in the elderly, can occur following any type of surgery and is associated with increased morbidity and mortality; it may also be associated with subsequent cognitive problems. Effective therapy for postoperative delirium remains elusive because the causative factors of delirium are likely multiple and varied.
Patients ≥ 65 years old undergoing elective knee arthroplasty were prospectively evaluated for postoperative Diagnostic and Statistical Manual of Mental Disorders-IV delirium. Exclusion criteria included dementia, mini-mental state exam score<24, delirium, clinically significant CNS/neurological disorder, current alcoholism, or any serious psychiatric disorder. Delirium was assessed on postoperative days 2 and 3 using standardized scales. Patients’ pre-existing medical conditions were obtained from medical charts. The occurrence of obstructive sleep apnea (OSA) was confirmed by contacting patients to check their polysomnography records. Data were analyzed using Pearson Chi-Square or Wilcoxon Rank Sum tests and multiple logistic regressions adjusted for effects of covariates.
Of 106 enrolled patients, 27 (25%) developed postoperative delirium. Of the 15 patients with obstructive sleep apnea, 8 (53%) experienced postoperative delirium, compared to 19 (20%) of the patients without obstructive sleep apnea (p=0.0123, OR: 4.3). Obstructive sleep apnea was the only statistically significant predictor of postoperative delirium in multivariate analyses.
This is the first prospective study employing validated measures of delirium to identify an association between pre-existing obstructive sleep apnea and postoperative delirium.
Delirium is a cognitive disorder. DSM-IV criteria for delirium must include both acute onset and fluctuating symptoms; disturbance of consciousness (including inattention); at least one of the following: disorganised thinking, disorientation, memory impairment or perceptual disturbance; and evidence of a putative causal medical condition. Traditionally, the course has been described as transient in which recovery is likely to be complete if the underlying aetiological factor is promptly corrected or is self-limited. The most common precipitating causes in elderly include sepsis, dehydration and drugs. Work-up for delirium is limited to septic screening, baseline investigations and imaging. Patients with delirium without focal signs and with either evidence for a medical aetiology of delirium or pre-diagnosed dementia are at a very low risk of having focal lesions in their contrast-enhanced CT or MRI. We are presenting an interesting case of delirium with urosepsis whose imaging revealed milliary brain tuberculomas on contrast-enhanced MRI.
It has been hypothesized that individuals without dementia with Alzheimer disease (AD) neuropathology may be in the preclinical stages of dementia and could be experiencing subtle cognitive decline. The purpose of this study was to compare longitudinal cognitive performance in oldest-old individuals without dementia with and without AD neuropathology.
The study included 58 individuals without dementia from The 90+ Autopsy Study, a population-based study of aging and dementia in individuals aged 90 and older. Participants had neurologic and neuropsychological testing every 6 months with an average of 3 years of follow-up. We compared the trajectory of cognitive performance on the Modified Mini-Mental State Examination (3MS) and the California Verbal Learning Test II (CVLT) by level of AD neuropathology. Based on Consortium to Establish a Registry for Alzheimer's Disease plaque staging, individuals were categorized as having low (none or sparse) or high (moderate or frequent) plaques. Based on Braak and Braak staging, participants were classified as having low (stages I–III) or high (IV–VI) tangles.
No significant differences were found in 3MS or CVLT cognitive performance over time based on plaque or tangle staging. Both high and low pathology groups showed modest improvements on the 3MS and CVLT consistent with learning effects.
AD neuropathology at autopsy is not associated with the trajectory of cognitive performance in the 3 years before death in oldest-old without dementia. Despite the presence of AD neuropathology at death, oldest-old without dementia display learning effects on cognitive tests. Further research is necessary to understand factors other than AD neuropathology that may affect cognition in the oldest-old.
Delirium affects 50–80% of patients in intensive care units and is associated with long-term cognitive impairment and increased risk of mortality. There are a paucity of data reporting the neuropathologic findings in ICU patients experiencing delirium. The purpose of this pilot, hypothesis-generating study was to evaluate brain autopsies in ICU patients who suffered from delirium in order to explore possible neuroanatomic correlates.
Utilizing study databases at Vanderbilt University we retrospectively identified patients who suffered from delirium in the ICU and subsequently died and received a brain autopsy during the same hospitalization. Information was also gathered regarding exposure to sedation and analgesia during ICU stay, number of delirium days, medical conditions surrounding death, and time with hypoxia and hypotension.
Patients’ mean age was 55 (SD±8.4), median number of days spent with delirium was 7 (±5 IQR). In 6 of 7 (86%) patients, pathologic lesions normally attributed to hypoxia or ischemia were noted in the hippocampus, pons, and striatum. Hippocampal lesions represented the most common neuropathological site of injury, present in 5 of 7 (71%) patients.
Hypoxic ischemic injury in multiple locations of the brain was a common finding in this pilot autopsy study of patients who had demonstrated delirium in the ICU. In particular, study of the hippocampus seems especially warranted in patients experiencing ICU delirium. Further correlation between clinical diagnoses, risk factors for neurological injury, neuroimaging, and neuropathology will help elucidate the mechanisms underlying acute brain dysfunction in our patients and long-term cognitive implications upon survival.
Delirium; Brain Autopsy; Neuropathology; Intensive Care; Hippocampus
Delirium affects 60– 80% of ventilated patients and is associated with worse clinical outcomes including death. Unfortunately there are limited data regarding the prevalence and risk factors of delirium in critically ill burn patients. The objectives of this study were to evaluate the prevalence of delirium in ventilated burn patients, using validated instruments, and to identify its risk factors.
Adult ventilated burn patients at 2 tertiary centers were prospectively evaluated for delirium using the Confusion Assessment Method in the ICU for 30 days or until ICU discharge. Patients with neurological injuries, severe dementia and those not expected to survive > 24 hours, were excluded. Markov logistic regression was used to identify risk factors of delirium, adjusting for clinically relevant covariates.
The 82 ventilated burn patients had a median (interquartile range) age of 48 (38, 62), APACHE II scores 27 (21, 30) and percent burns of 20 (7, 32). Prevalence of delirium was 77% with a median duration of 3 (1, 6) days. Exposure to benzodiazepines was an independent risk factor for the development of delirium [Odds Ratio 6.8, (confidence interval 3.1, 15), p <0.001) while exposure to intravenous opiates [0.5 (0.4, 0.6), p <0.001] and methadone [0.7 (0.5, 9), p=0.02] were both associated with a lower risk of delirium.
Delirium occurred atleast once in approximately 80% of ventilated burn patients. Exposure to benzodiazepines was an independent risk factor for delirium while opiates and methadone reduced the risk of developing delirium, possibly through reduction of pain in these patients.
burn critically ill; delirium; benzodiazepines; risk factors; mechanically ventilated
Delirium often has a poor outcome, but why some people have incomplete recovery is not well understood. Our objective was to identify factors associated with short-term (by discharge) and long-term (by 6 month) incomplete recovery of function following delirium.
In a prospective cohort study of elderly patients with delirium seen by geriatric medicine services, function was assessed at baseline, at hospital discharge and at six months.
Of 77 patients, vital and functional status at 6 months was known for 71, of whom 21 (30%) had died. Incomplete functional recovery, defined as ≥10 point decline in the Barthel Index, compared to pre-morbid status, was present in 27 (54%) of the 50 survivors. Factors associated with death or loss of function at hospital discharge were frailty, absence of agitation (hypoactive delirium), a cardiac cause and poor recognition of delirium by the treating service. Frailty, causes other than medications, and poor recognition of delirium by the treating service were associated with death or poor functional recovery at 6 months.
Pre-existing frailty, cardiac cause of delirium, and poor early recognition by treating physicians are associated with worse outcomes. Many physicians view the adverse outcomes of delirium as intractable. While in some measure this might be true, more skilled care is a potential remedy within their grasp.
Delirium is common, deadly, and costly in people with dementia. The purpose of this pilot study was to test the feasibility of the computerized decision support component of an intervention strategy—Early Nurse Detection of Delirium Superimposed on Dementia—designed to improve nurse assessment and detection of delirium superimposed on dementia. This pilot study enrolled and followed 15 individuals with dementia (mean age = 83, mean admission Mini-Mental State Examination score = 14.8) and their caregivers daily for the duration of their hospitalization. Results indicated 100% adherence by nursing staff on the delirium assessment decision support screens and 75% adherence on the management screens. Despite the prevalence and severity of delirium in people with dementia, there are currently no published reports of the use of the electronic medical record in delirium detection and management. Success of this effort may encourage similar use of information technology in other settings.