Alzheimer Disease: Stern Y

Dubois B, Feldman HH, Jacova C, Dekosky ST, Barberger-Gateau P, Cummings J, Delacourte A, Galasko D, Gauthier S, Jicha G, Meguro K, O'brien J, Pasquier F, Robert P, Rossor M, Salloway S, Stern Y, Visser PJ, Scheltens P. · INSERM U610, Hôpital de la Salpêtrière, Paris, France. · Lancet Neurol. · Pubmed #17616482 No free full text.

Abstract: The NINCDS-ADRDA and the DSM-IV-TR criteria for Alzheimer's disease (AD) are the prevailing diagnostic standards in research; however, they have now fallen behind the unprecedented growth of scientific knowledge. Distinctive and reliable biomarkers of AD are now available through structural MRI, molecular neuroimaging with PET, and cerebrospinal fluid analyses. This progress provides the impetus for our proposal of revised diagnostic criteria for AD. Our framework was developed to capture both the earliest stages, before full-blown dementia, as well as the full spectrum of the illness. These new criteria are centred on a clinical core of early and significant episodic memory impairment. They stipulate that there must also be at least one or more abnormal biomarkers among structural neuroimaging with MRI, molecular neuroimaging with PET, and cerebrospinal fluid analysis of amyloid beta or tau proteins. The timeliness of these criteria is highlighted by the many drugs in development that are directed at changing pathogenesis, particularly at the production and clearance of amyloid beta as well as at the hyperphosphorylation state of tau. Validation studies in existing and prospective cohorts are needed to advance these criteria and optimise their sensitivity, specificity, and accuracy.

Stern Y. · Cognitive Neuroscience Division of the Taub Institute, 630 W. 168th Street, New York, NY 10032, USA. · Alzheimer Dis Assoc Disord. · Pubmed #16917199 No free full text.

Abstract: Epidemiologic evidence suggests that individuals with higher IQ, education, occupational attainment, or participation in leisure activities have a reduced risk of developing Alzheimer disease (AD). The concept of cognitive reserve (CR) posits that individual differences in how tasks are processed provide differential reserve against brain pathology or age-related changes. This may take 2 forms. In neural reserve, preexisting brain networks that are more efficient or have greater capacity may be less susceptible to disruption. In neural compensation, alternate networks may compensate for pathology's disruption of preexisting networks. Imaging studies have begun to identify the neural substrate of CR. Because CR may modulate the clinical expression of AD pathology, it is an important consideration in studies of "preclinical" AD and treatment studies. There is also the possibility that directly enhancing CR may help forestall the diagnosis of AD.

Stern Y. · Cognitive Neuroscience Division of the Taub Institute, New York, NY 10032, USA. · Alzheimer Dis Assoc Disord. · Pubmed #16772747 No free full text.

Abstract: Epidemiologic evidence suggests that individuals with higher IQ, education, occupational attainment, or participation in leisure activities have a reduced risk of developing Alzheimer disease (AD). The concept of cognitive reserve (CR) posits that individual differences in how tasks are processed provide differential reserve against brain pathology or age-related changes. This may take 2 forms. In neural reserve, preexisting brain networks that are more efficient or have greater capacity may be less susceptible to disruption. In neural compensation, alternate networks may compensate for pathology's disruption of preexisting networks. Imaging studies have begun to identify the neural substrate of CR. Because CR may modulate the clinical expression of AD pathology, it is an important consideration in studies of "preclinical" AD and treatment studies. There is also the possibility that directly enhancing CR may help forestall the diagnosis of AD.

Cosentino S, Stern Y. · Cognitive Neuroscience Division of the Taub Institute for Research in Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York 10032, USA. · J Int Neuropsychol Soc. · Pubmed #16519270 No free full text.

Abstract: Anosognosia, disordered awareness of cognitive and behavioral deficits, is a striking and common symptom of Alzheimer's disease (AD), yet its etiology, clinical correlates, and prognostic value are unclear. Historically, disordered awareness has been a conceptually challenging phenomenon, evidenced by the numerous and diverse theories that aim to explain the manner in which this syndrome arises. We review many of these theories, focusing on the neuroanatomic substrates of awareness, and highlighting the potential roles of critical regions such as the right prefrontal and parietal cortices in enabling self-awareness. We then address methodological limitations such as use of subjective measurement tools that likely contribute to the conceptual ambiguity surrounding anosognosia. We argue that metacognitive techniques used in healthy adults, such as the Feeling of Knowing task, offer models for dissecting awareness into clear and identifiable cognitive components in patients with AD. We critique several studies that have pioneered such tasks in AD, and offer guidelines for future implementation of such methods. A final goal of this review is to advocate for a multidimensional approach to studying metacognitive skills that will facilitate the objective investigation of deficit awareness as it relates to a variety of disease variables such as prognosis, neuropsychological profile, neuropathological distribution, psychiatric symptoms, and clinical course.

Scarmeas N, Stern Y. · Columbia University Medical Center, 622 West 168th Street, PH 19th Floor, New York, NY 10032, USA. · Curr Psychiatry Rep. · Pubmed #16513038 No free full text.

Abstract: Many studies have investigated APOE-related differences in cerebral structure, blood flow, metabolism, and activation in an attempt to detect early brain changes in subjects at risk for Alzheimer's disease (AD). Structural magnetic resonance imaging studies have produced conflicting results, with some failing to detect APOE-related differences and others suggesting that epsilon4 carriers have more pronounced atrophy, particularly at medial temporal structures. All functional imaging studies done during rest in middle-aged and elderly subjects have found decreased cerebral metabolism for epsilon4 carriers (mostly in areas that usually are affected by AD), and some have reported faster cerebral metabolic reductions over time. Areas with decreased resting cerebral perfusion and metabolism, in addition to other areas with increased perfusion, have been reported in young epsilon4 carriers. Imaging studies done during the performance of various cognitive tasks in middle-aged and elderly subjects, and a single study in young subjects, have produced mixed results with regionally nonspecific increased, decreased, or nondifferential APOE-related activations depending on the cognitive task used. APOE-related findings in imaging studies of nondemented subjects may be the result of incipient AD pathologic changes or of genetic heterogeneity in brain structure and function.

Scarmeas N, Stern Y. · Columbia Presbyterian Medical Center, 622 West 168th Street, PH 19th Floor, New York, NY 10032, USA. · Curr Neurol Neurosci Rep. · Pubmed #15324603 No free full text.

Abstract: Epidemiologic evidence suggests that higher occupational attainment and education, as well as increased participation in intellectual, social, and physical aspects of daily life, are associated with slower cognitive decline in healthy elderly and may reduce the risk of incident Alzheimer's disease (AD). There is also evidence from structural and functional imaging studies that patients with such life experiences can tolerate more AD pathology before showing signs of clinical dementia. It has been hypothesized that such aspects of life experience may result in functionally more efficient cognitive networks and, therefore, provide a cognitive reserve that delays the onset of clinical manifestations of dementia. In this article, we review some of the relevant literature of the noted associations between markers of cognitive reserve and AD and discuss the possible mechanisms that may explain these associations.

Scarmeas N, Stern Y. · Cognitive Neuroscience Division, Department of Neurology, Taub Institute for Research in Alzheimer's Disease and the Aging Brain, and College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA. · J Clin Exp Neuropsychol. · Pubmed #12815500 No free full text.

Abstract: The concept of cognitive reserve (CR) suggests that innate intelligence or aspects of life experience like educational or occupational attainments may supply reserve, in the form of a set of skills or repertoires that allows some people to cope with progressing Alzheimer's disease (AD) pathology better than others. There is epidemiological evidence that lifestyle characterized by engagement in leisure activities of intellectual and social nature is associated with slower cognitive decline in healthy elderly and may reduce the risk of incident dementia. There is also evidence from functional imaging studies that subjects engaging in such leisure activities can clinically tolerate more AD pathology. It is possible that aspects of life experience like engagement in leisure activities may result in functionally more efficient cognitive networks and therefore provide a CR that delays the onset of clinical manifestations of dementia.

Stern Y. · G.H. Sergievsky Center, The Taub Institute, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA. · J Int Neuropsychol Soc. · Pubmed #11939702 No free full text.

Abstract: The idea of reserve against brain damage stems from the repeated observation that there does not appear to be a direct relationship between the degree of brain pathology or brain damage and the clinical manifestation of that damage. This paper attempts to develop a coherent theoretical account of reserve. One convenient subdivision of reserve models revolves around whether they envision reserve as a passive process, such as in brain reserve or threshold, or see the brain as actively attempting to cope with or compensate for pathology, as in cognitive reserve. Cognitive reserve may be based on more efficient utilization of brain networks or of enhanced ability to recruit alternate brain networks as needed. A distinction is suggested between reserve, the ability to optimize or maximize normal performance, and compensation, an attempt to maximize performance in the face of brain damage by using brain structures or networks not engaged when the brain is not damaged. Epidemiologic and imaging data that help to develop and support the concept of reserve are presented.

Desmond DW, Erkinjuntti T, Sano M, Cummings JL, Bowler JV, Pasquier F, Moroney JT, Ferris SH, Stern Y, Sachdev PS, Hachinski VC. · Department of Neurology, Columbia University, College of Physicians and Surgeons, New York, New York, USA. · Alzheimer Dis Assoc Disord. · Pubmed #10609678 No free full text.

Abstract: Dementia is common among patients with cerebrovascular disease, particularly in a setting of one or more clinically evident strokes. Prior cohort and case studies have suggested that the cognitive syndrome of vascular dementia is characterized by predominant executive dysfunction, in contrast to the deficits in memory and language function that are typical of patients with Alzheimer disease. The course of cognitive decline may also differ between those dementia subtypes, with many, but not all, patients with vascular dementia exhibiting a stepwise course of decline caused by recurrent stroke and most patients with Alzheimer disease exhibiting a gradually progressive course of decline. The findings of prior studies of the cognitive syndrome of vascular dementia must be interpreted with caution, however, because of (1) possible inaccuracies in the determination of the dementia subtype and the loss of precision that might result from pooling heterogeneous subgroups of patients with vascular dementia, (2) difficulties inherent in identifying a pattern of strengths and weaknesses in patients who are required to have memory impairment and other deficits to meet operationalized criteria for dementia, and (3) the use of limited test batteries whose psychometric properties are incompletely understood. Specific questions that should be addressed by future studies are discussed.

Vliet EC, Manly J, Tang MX, Marder K, Bell K, Stern Y. · Gertrude H. Sergievsky Center, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA. · J Int Neuropsychol Soc. · Pubmed #12901778 No free full text.

Abstract: Test scores from a comprehensive neuropsychological battery administered to 1602 subjects consisting of 1347 subjects with probable Alzheimer's disease (AD), 100 subjects with questionable dementia (QD) and 155 non-demented elderly control subjects were cross-sectionally analyzed. Subjects with probable AD were categorized as mild (n = 244), moderate (n = 480), severe (n = 376), and very severe (n = 247) according to modified mini mental status exam (mMMSE) scores. Mean scores on individual neuropsychological tests are provided for each group of subjects. Stratified random sampling was performed to select a sample of mild AD subjects who were matched in age and education to non-demented elderly controls, and analyses focused on the performance of QD subjects and mild AD subjects, whose scores were compared to those of the elderly control subjects. Selected scores were organized by cognitive domain and logistic regressions were used to determine the domains and individual tests within each that were most predictive of group status. Results suggested a profile of scores associated with QD and mild AD including impaired recall of verbal information for both groups. Areas of lower functioning in QD subjects as compared to elderly controls included category fluency and visuospatial ability.

Scarmeas N, Brandt J, Albert M, Devanand DP, Marder K, Bell K, Ciappa A, Tycko B, Stern Y. · Cognitive Neuroscience Division, Taub Institute for Research in Alzheimer's Disease and the Aging Brain, New York, NY, USA. · Neurology. · Pubmed #11971084 No free full text.

Abstract: BACKGROUND: Psychiatric symptoms occur frequently in the course of AD, are a frequent contributor to institutionalization, predict cognitive decline and death, and often require treatment with psychotropic medications. Previous studies investigating the association between APOE genotype and psychiatric symptomatology in AD have reported contradictory results. OBJECTIVE: To determine whether APOE genotype predicts incident psychiatric symptomatology in patients with AD. METHODS: Eighty-seven patients with AD at early stages and no psychiatric history were followed semiannually for up to 9.3 years (mean 5.5 years) for development of delusions, illusions, hallucinations, behavioral symptoms, and depression. Cox proportional hazards models were used to examine the relative risk for incident psychiatric symptomatology (outcome) in relation to APOE genotype (predictor). RESULTS: The presence of one epsilon4 allele carried a 2.5-fold risk, whereas the presence of two epsilon4 alleles carried a 5.6-fold risk for development of delusions. The associations remained significant even when age, ethnicity, sex, education, duration of disease, and cognitive and functional performance were controlled for. The presence of two epsilon4 alleles was associated with reduced risk for developing hallucinations in the adjusted analysis only. No significant associations were detected between APOE genotype and the incidence of illusions, behavioral symptoms, or depression. CONCLUSION: The presence of one or more epsilon4 alleles is a significant predictor for the incidence of delusions in the course of AD.

Helzner EP, Luchsinger JA, Scarmeas N, Cosentino S, Brickman AM, Glymour MM, Stern Y. · Gertrude H. Sergievsky Center, Columbia University Medical Center, NY, New York, USA. · Arch Neurol. · Pubmed #19273753 No free full text.

Abstract: BACKGROUND: Vascular factors including medical history (heart disease, stroke, diabetes, and hypertension), smoking, and prediagnosis blood lipid measurements (cholesterol: total, high-density lipoprotein, low-density lipoprotein [LDL-C], and triglyceride concentrations) may be predictors for progression of Alzheimer disease (AD). OBJECTIVE: To determine whether prediagnosis vascular risk factors are associated with progression of AD. DESIGN: Inception cohort followed up longitudinally for a mean of 3.5 (up to 10.2) years. SETTING: Washington Heights/Inwood Columbia Aging Project, New York, New York. Patients One hundred fifty-six patients with incident AD (mean age at diagnosis, 83 years). Main Outcome Measure Change in a composite score of cognitive ability from diagnosis onward. RESULTS: In generalized estimating equation models (adjusted for age, race/ethnicity, and years of education), higher cholesterol (total cholesterol and LDL-C) concentrations and history of diabetes were associated with faster cognitive decline. Each 10-U increase in cholesterol and LDL-C was associated with a 0.10-SD decrease in cognitive score per year of follow-up (P < .001 for total cholesterol; P = .001 for LDL-C). High-density lipoprotein cholesterol and triglyceride concentrations were not associated with rate of decline. A history of diabetes was associated with an additional 0.05-SD decrease in cognitive score per year (P = .05). History of heart disease and stroke were associated with cognitive decline only in carriers of the apolipoprotein E epsilon4 (APOE-epsilon4) gene. In a final generalized estimating equation model that included high-density lipoprotein cholesterol and LDL-C concentrations and history of diabetes, only higher LDL-C was independently associated with faster cognitive decline. CONCLUSION: Higher prediagnosis total cholesterol and LDL-C concentrations and history of diabetes were associated with faster cognitive decline in patients with incident AD, which provides further evidence for the role of vascular risk factors in the course of AD.

Scarmeas N, Stern Y, Mayeux R, Manly JJ, Schupf N, Luchsinger JA. · Department of Neurology, Columbia University Medical Center, New York, NY 10032, USA. · Arch Neurol. · Pubmed #19204158 links to  free full text

Abstract: BACKGROUND: Higher adherence to the Mediterranean diet (MeDi) may protect from Alzheimer disease (AD), but its association with mild cognitive impairment (MCI) has not been explored. OBJECTIVE: To investigate the association between the MeDi and MCI. DESIGN, SETTING, AND PATIENTS: In a multiethnic community study in New York, we used Cox proportional hazards to investigate the association between adherence to the MeDi (0-9 scale; higher scores indicate higher adherence) and (1) the incidence of MCI and (2) the progression from MCI to AD. All of the models were adjusted for cohort, age, sex, ethnicity, education, APOE genotype, caloric intake, body mass index, and duration between baseline dietary assessment and baseline diagnosis. MAIN OUTCOME MEASURES: Incidence of MCI and progression from MCI to AD. RESULTS: There were 1393 cognitively normal participants, 275 of whom developed MCI during a mean (SD) follow-up of 4.5 (2.7) years (range, 0.9-16.4 years). Compared with subjects in the lowest MeDi adherence tertile, subjects in the middle tertile had 17% less risk (hazard ratio [HR] = 0.83; 95% confidence interval [CI], 0.62-1.12; P = .24) of developing MCI and those in the highest tertile had 28% less risk (HR = 0.72; 95% CI, 0.52-1.00; P = .05) of developing MCI (trend HR = 0.85; 95% CI, 0.72-1.00; P for trend = .05). There were 482 subjects with MCI, 106 of whom developed AD during a mean (SD) follow-up of 4.3 (2.7) years (range, 1.0-13.8 years). Compared with subjects in the lowest MeDi adherence tertile, subjects in the middle tertile had 45% less risk (HR = 0.55; 95% CI, 0.34-0.90; P = .01) of developing AD and those in the highest tertile had 48% less risk (HR = 0.52; 95% CI, 0.30-0.91; P = .02) of developing AD (trend HR = 0.71; 95% CI, 0.53-0.95; P for trend = .02). CONCLUSIONS: Higher adherence to the MeDi is associated with a trend for reduced risk of developing MCI and with reduced risk of MCI conversion to AD.

Helzner EP, Scarmeas N, Cosentino S, Tang MX, Schupf N, Stern Y. · Gertrude H Sergievsky Center, Columbia University Medical Center, New York, NY 10032, USA. · Neurology. · Pubmed #18981370 No free full text.

Abstract: OBJECTIVE: To describe factors associated with survival in Alzheimer disease (AD) in a multiethnic, population-based longitudinal study. METHODS: AD cases were identified in the Washington Heights Inwood Columbia Aging Project, a longitudinal, community-based study of cognitive aging in Northern Manhattan. The sample comprised 323 participants who were initially dementia-free but developed AD during study follow-up (incident cases). Participants were followed for an average of 4.1 (up to 12.6) years. Possible factors associated with shorter lifespan were assessed using Cox proportional hazards models with attained age as the time to event (time from birth to death or last follow-up). In subanalyses, median postdiagnosis survival durations were estimated using postdiagnosis study follow-up as the timescale. RESULTS: The mortality rate was 10.7 per 100 person-years. Mortality rates were highest [corrected] among those diagnosed at older ages, and among non-Hispanic whites compared to [corrected] Hispanic [corrected] The median lifespan of the entire sample was 92.2 years (95% CI: 90.3, 94.1). In a multivariable-adjusted Cox model, history of diabetes and history of hypertension were independently associated with a shorter lifespan. No differences in lifespan were seen by race/ethnicity after multivariable adjustment. The median postdiagnosis survival duration was 3.7 years among non-Hispanic whites, 4.8 years among African Americans, and 7.6 years among Hispanics. CONCLUSION: Factors influencing survival in Alzheimer disease include race/ethnicity and comorbid diabetes and hypertension.

Zhu CW, Leibman C, McLaughlin T, Zbrozek AS, Scarmeas N, Albert M, Brandt J, Blacker D, Sano M, Stern Y. · Geriatric Research, Education, and Clinical Center (GRECC), James J. Peters VA Medical Center, Bronx, NY, NY 10468, USA. · Dement Geriatr Cogn Disord. · Pubmed #18946219 links to  free full text

Abstract: BACKGROUND/AIMS: To examine the incremental effect of patients' dependence on others, on cost of medical and nonmedical care, and on informal caregiving hours over time. METHODS: Data are obtained from 172 patients from the Predictors Study, a large, multicenter cohort of patients with probable Alzheimer disease (AD) followed annually for 4 years in 3 University-based AD centers in the USA. Enrollment required a modified Mini-Mental State Examination score >or=30. We examined the effects of patient dependence (measured by the Dependence Scale, DS) and function (measured by the Blessed Dementia Rating Scale, BDRS) on medical care cost, nonmedical care cost, and informal caregiving time using random effects regression models. RESULTS: A one-point increase in DS score was associated with a 5.7% increase in medical cost, a 10.5% increase in nonmedical cost, and a 4.1% increase in caregiving time. A one-point increase in BDRS score was associated with a 7.6% increase in medical cost, a 3.9% increase in nonmedical cost and an 8.7% increase in caregiving time. CONCLUSIONS: Both functional impairment and patient dependence were associated with higher costs of care and caregiving time. Measures of functional impairment and patient dependence provide unique and incremental information on the overall impact of AD on patients and their caregivers.

Scherer RK, Scarmeas N, Brandt J, Blacker D, Albert MS, Stern Y. · Cognitive Neuroscience Division, Taub Institute for Research in Alzheimer's Disease and the Aging Brain, Gertrude H. Sergievsky Center, Department of Neurology, Columbia University Medical Center, 630 West 168th St., P&S Box 16, New York, NY 10032, USA. · J Gerontol A Biol Sci Med Sci. · Pubmed #18840808 No free full text.

Abstract: BACKGROUND: Although there has been much research devoted to understanding the predictors of nursing home placement (NHP) in Alzheimer's disease (AD) patients, there is currently a lack of research concerning the predictors of home health care. The objective of this study was to examine whether the Dependence Scale can predict home health aide (HHA) use. METHODS: The sample is drawn from the Predictors Study, a large, multicenter cohort of patients with probable AD, prospectively followed annually for up to 7 years in three university-based AD centers in the United States. Markov analyses (n=75) were used to calculate annual transition probabilities for the "new onset" of HHA use (instances where an HHA was absent at the previous visit, but present at the next visit) as a function of HHA presence at the preceding year's visit and dependence level at that preceding year's visit. RESULTS: The dependence level at the previous year's visit was a significant predictor of HHA use at the next year's visit. Three specific items of the Dependence Scale (needing household chores done for oneself, needing to be watched or kept company when awake, and needing to be escorted when outside) were significant predictors of the presence of an HHA. CONCLUSION: The Dependence Scale is a valuable tool for predicting HHA use in AD patients. Obtaining a better understanding of home health care in AD patients may help delay NHP and have a positive impact on the health and well-being of both the caregiver and the patient.

Brickman AM, Honig LS, Scarmeas N, Tatarina O, Sanders L, Albert MS, Brandt J, Blacker D, Stern Y. · Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, 630 W 168th St, Campus Box 16, New York, NY 10032, USA. · Arch Neurol. · Pubmed #18779424 No free full text.

Abstract: OBJECTIVE: To determine if baseline measurements of cerebral atrophy and severity of white matter hyperintensity (WMH) predict the rate of future cognitive decline in patients with Alzheimer disease (AD). DESIGN: Data were drawn from the Predictors Study, a longitudinal study that enrolls patients with mild AD and reassesses them every 6 months with use of the Columbia modified Mini-Mental State (mMMS) examination (score range, 0-57). Magnetic resonance images were analyzed to determine the severity of WMH, using the Scheltens scale, and the degree of atrophy, using the bicaudate ratio. Generalized estimating equations were used to determine whether severity of baseline magnetic resonance image measurements and their interaction predicted the rate of mMMS score decline at subsequent visits. SETTING: Three university-based AD centers in the United States. PARTICIPANTS: At baseline, 84 patients with AD from the Predictors Study received structural magnetic resonance imaging and were selected for analysis. They had a mean of 6 follow-up evaluations. Main Outcome Measure The mMMS score. RESULTS: Generalized estimating equation models demonstrated that the degree of baseline atrophy (beta = -0.316; P = .04), the severity of WMH (beta = -0.173; P = .03), and their interaction (beta = -6.061; P = .02) predicted the rate of decline in mMMS scores. CONCLUSIONS: Both degree of cerebral atrophy and severity of WMH are associated with the rapidity of cognitive decline in AD. Atrophy and WMH may have a synergistic effect on future decline in AD, such that patients with a high degree of both have a particularly precipitous cognitive course. These findings lend further support to the hypothesis that cerebrovascular pathological abnormalities contribute to the clinical syndrome of AD.

Devanand DP, Liu X, Tabert MH, Pradhaban G, Cuasay K, Bell K, de Leon MJ, Doty RL, Stern Y, Pelton GH. · Division of Geriatric Psychiatry, New York State Psychiatric Institute, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA. · Biol Psychiatry. · Pubmed #18723162 No free full text.

Abstract: BACKGROUND: The utility of combining early markers to predict conversion from mild cognitive impairment (MCI) to Alzheimer's Disease (AD) remains uncertain. METHODS: Included in the study were 148 outpatients with MCI, broadly defined, followed at 6-month intervals. Hypothesized baseline predictors for follow-up conversion to AD (entire sample: 39/148 converters) were cognitive test performance, informant report of functional impairment, apolipoprotein E genotype, olfactory identification deficit, and magnetic resonance imaging (MRI) hippocampal and entorhinal cortex volumes. RESULTS: In the 3-year follow-up patient sample (33/126 converters), five of eight hypothesized predictors were selected by backward and stepwise logistic regression: Pfeffer Functional Activities Questionnaire (FAQ; informant report of functioning), University of Pennsylvania Smell Identification Test (UPSIT; olfactory identification), Selective Reminding Test (SRT) immediate recall (verbal memory), MRI hippocampal volume, and MRI entorhinal cortex volume. For 10% false positives (90% specificity), this five-predictor combination showed 85.2% sensitivity, combining age and Mini-Mental State Examination (MMSE) showed 39.4% sensitivity; combining age, MMSE, and the three clinical predictors (SRT immediate recall, FAQ, and UPSIT) showed 81.3% sensitivity. Area under ROC curve was greater for the five-predictor combination (.948) than age plus MMSE (.821; p = .0009) and remained high in subsamples with MMSE > or = 27/30 and amnestic MCI. CONCLUSIONS: The five-predictor combination strongly predicted conversion to AD and was markedly superior to combining age and MMSE. Combining the clinically administered measures also led to strong predictive accuracy. If independently replicated, the findings have potential utility for early detection of AD.

Zhu CW, Leibman C, McLaughlin T, Scarmeas N, Albert M, Brandt J, Blacker D, Sano M, Stern Y. · Geriatric Research, Education, and Clinical Center, Program of Research on Serious Physical and Mental Illness, James J Peters Veterans Affairs Medical Center, Bronx, New York 10468, USA. · J Am Geriatr Soc. · Pubmed #18662215 links to  free full text

Abstract: OBJECTIVES: To estimate incremental effects of patients' dependence and function on costs of care during the early stages of Alzheimer's disease (AD) and to compare strengths of their relationships with different cost components. DESIGN: Multicenter, cross-sectional, observational study. SETTING: Three university hospitals in the United States. PARTICIPANTS: One hundred seventy-nine community-living patients with probable AD, with modified Mini-Mental State Examination scores of 30 or higher. MEASUREMENTS: Patients' dependence was measured using the Dependence Scale (DS). Functional capacity was measured using the Blessed Dementia Rating Scale (BDRS). Total cost was measured by summing direct medical costs and informal costs. Direct medical costs included costs of hospitalization, outpatient treatment and procedures, assistive devices, and medications. Informal costs were estimated from time spent helping with basic and instrumental activities of daily living for up to three caregivers per patient using national average hourly earnings as wage rate. RESULTS: DS and BDRS were associated with higher total cost; a 1-point increase in DS was associated with a $1,832 increase in total cost, and a 1-point increase in BDRS was associated with a $3,333 increase. Examining component costs separately identified potential differences between DS and BDRS. A 1-point increase in BDRS was associated with a $1,406 increase in direct medical cost. A 1-point increase in DS was associated with a $1,690 increase in informal cost. CONCLUSION: Patients' dependence and function related differently to direct medical and informal cost, suggesting that measures of function and dependence provided unique information for explaining variations in cost of care for patients with AD, highlighting the value in measuring both constructs.

Zhu CW, Scarmeas N, Stavitsky K, Albert M, Brandt J, Blacker D, Sano M, Stern Y. · Geriatric Research, Education, and Clinical Center and Program of Research on Serious Physical and Mental Illness, Targeted Research Enhancement Program, James J. Peters VA Medical Center, Bronx, NY, USA. · Alzheimers Dement. · Pubmed #18631979 links to  free full text

Abstract: BACKGROUND: The objective of this study was to compare total costs of care and its major components for community-living patients with Alzheimer's disease (AD) or dementia with Lewy bodies (DLB). This cross-sectional analysis of baseline data from the Predictors II Study took place in three university-based AD centers in the U.S. METHODS: Community-living patients clinically diagnosed with probable AD (n = 170) or DLB (n = 25) with a modified Mini-Mental State examination (mMMS) score > or =30, equivalent to a score of approximately > or =16 on the Folstein Mini-Mental State Examination (MMSE), participated in this study. Patient and informant reported on patients' use of direct medical care, direct nonmedical care, and informal care. Patients' clinical and demographic characteristics included global cognitive status (measured by MMSE), functional capacity (measured by Blessed Dementia Rating Scale), psychotic symptoms, behavioral problems, depressive symptoms, extrapyramidal signs, comorbidities, age, and sex. Costs were compared by using covariate matching methods. RESULTS: Unadjusted total costs and direct medical costs were not significantly different between AD and DLB patients. Compared with AD patients, unadjusted indirect costs were significantly higher and unadjusted direct nonmedical costs were significantly lower among DLB patients. After adjusting for age, sex, cognitive and functional status, differences in all cost components between DLB and AD patients were no longer statistically significant. CONCLUSIONS: Apparent cost differences were largely attributed to differences in patients' cognitive and functional status. However, the small sample size for DLB patients might have limited power to detect statistically significant differences in costs of care between these groups.

Steinerman JR, Irizarry M, Scarmeas N, Raju S, Brandt J, Albert M, Blacker D, Hyman B, Stern Y. · Departments of Neurology, Columbia University Medical Center, 630 W 168th St, P&S Box 16, New York, NY 10032, USA. · Arch Neurol. · Pubmed #18625856 links to  free full text

Abstract: OBJECTIVE: To determine whether beta-amyloid (Abeta) peptides segregated into distinct biochemical compartments would differentially correlate with clinical severity of Alzheimer disease (AD). DESIGN: Clinicopathologic correlation study. PARTICIPANTS: Twenty-seven patients from a longitudinal study of AD and 13 age- and sex-matched controls without a known history of cognitive impairment or dementia were included in this study. INTERVENTIONS: Temporal and cingulate neocortex were processed using a 4-step extraction, yielding biochemical fractions that are hypothesized to be enriched with proteins from distinct anatomical compartments: TRIS (extracellular soluble), Triton (intracellular soluble), sodium dodecyl sulfate (SDS) (membrane associated), and formic acid (extracellular insoluble). Levels of Abeta(40) and Abeta(42) were quantified in each biochemical compartment by enzyme-linked immunosorbent assay. RESULTS: The Abeta(42) level in all biochemical compartments was significantly elevated in patients with AD vs controls (P < .01). The Abeta(40) levels in the TRIS and formic acid fractions were elevated in patients with AD (temporal, P < .01; cingulate, P = .03); however, Triton and SDS Abeta(40) levels were similar in patients with AD and in controls. Functional impairment proximal to death correlated with Triton Abeta(42) (r = 0.48, P = .02) and SDS Abeta(42) (r = 0.41, P = .04) in the temporal cortex. Faster cognitive decline was associated with elevated temporal SDS Abeta(42) levels (P < .001), whereas slower decline was associated with elevated cingulate formic acid Abeta(42) and SDS Abeta(42) levels (P = .02 and P = .01, respectively). CONCLUSION: Intracellular and membrane-associated Abeta, especially Abeta(42) in the temporal neocortex, may be more closely related to AD symptoms than other measured Abeta species.

Zhu CW, Torgan R, Scarmeas N, Albert M, Brandt J, Blacker D, Sano M, Stern Y. · Geriatric Research, Education, and Clinical Center (GRECC), James J. Peters VA Medical Center, Bronx, NY 10468, USA. · Home Health Care Serv Q. · Pubmed #18510196 links to  free full text

Abstract: OBJECTIVES: To (1) compare home health and informal (unpaid) services utilization among patients with Alzheimer's disease (AD), (2) examine longitudinal changes in services use, and (3) estimate possible interdependence of home health and informal care utilization. METHODS: The sample is drawn from the Predictors Study, a large, multicenter cohort of patients with probable AD, prospectively followed annually for up to 7 years in three university-based AD centers. Bivariate probit models estimated the effects of patient characteristics on home health and informal care utilization. RESULTS: A large majority of the patients (80.6%) received informal care with a smaller proportion (18.6%) receiving home health services. Home health services utilization increased from 9.9% at baseline to 34.5% in year 4. Among users, number of days that services were provided in three-month recall increased from 21.9 to 56 days over time. Home health services utilization was significantly associated with function, depressive symptoms, being female, and not living with a spouse. Informal care utilization was significantly associated with cognition, function, comorbidities, and living with a spouse or child. CONCLUSIONS: Home health and informal care utilization relate differently to patient characteristics. Utilization of home health care or informal care was not influenced by utilization of the other.

Siedlecki KL, Honig LS, Stern Y. · Cognitive Neuroscience Division, Taub Institute, Columbia University College of Physicians and Surgeons. · Neuropsychology. · Pubmed #18444718 No free full text.

Abstract: An exploratory factor analysis (EFA) and a series of confirmatory factor analyses were conducted on 17 variables designed to assess different cognitive abilities in a sample of healthy older adults. In the EFA, 4 factors emerged corresponding to language, memory, processing speed, and fluid ability constructs. The results of the confirmatory factor analyses suggested that a 5-factor model with an additional Attention factor improved the fit. The invariance of the 5-factor model was examined across 3 groups: a group of cognitively healthy older adults, a group of patients diagnosed with questionable dementia (QD), and a group of patients diagnosed with probable Alzheimer's disease (AD). Results of the invariance analysis suggest that the model may have configural invariance across the 3 groups but not metric invariance. Specifically, preliminary analyses suggest that the memory construct may represent something different in the QD and AD groups as compared to the healthy older adult group, consistent with the underlying pathology in early AD.

Cosentino S, Scarmeas N, Helzner E, Glymour MM, Brandt J, Albert M, Blacker D, Stern Y. · Cognitive Neuroscience Division of the Gertrude H. Sergievsky Center, Columbia University Medical Center, New York, NY 10032, USA. · Neurology. · Pubmed #18401023 links to  free full text

Abstract: OBJECTIVE: To determine whether APOE epsilon 4 predicts rate of cognitive change in incident and prevalent Alzheimer disease (AD). METHODS: Individuals were recruited from two longitudinal cohort studies-the Washington Heights and Inwood Columbia Aging Project (WHICAP; population-based) and the Predictors Study (clinic-based)--and were followed for an average of 4 years. Three samples of participants diagnosed with AD, with diverse demographic characteristics and baseline cognitive functioning, were studied: 1) 199 (48%) of the incident WHICAP cases; 2) 215 (54%) of the prevalent WHICAP cases; and 3) 156 (71%) of the individuals diagnosed with AD in the Predictors Study. Generalized estimating equations were used to test whether rate of cognitive change, measured using a composite cognitive score in WHICAP and the Mini-Mental State Examination in Predictors, varied as a function of epsilon 4 status in each sample. RESULTS: The presence of at least one epsilon 4 allele was associated with faster cognitive decline in the incident population-based AD group (p = 0.01). Parallel results were produced for the two prevalent dementia samples only when adjusting for disease severity or excluding the most impaired participants from the analyses. CONCLUSION: APOE epsilon 4 may influence rate of cognitive decline most significantly in the earliest stages of Alzheimer disease.

Habeck C, Foster NL, Perneczky R, Kurz A, Alexopoulos P, Koeppe RA, Drzezga A, Stern Y. · Taub Institute, Columbia University Medical Center, New York, NY 10032, USA. · Neuroimage. · Pubmed #18343688 links to  free full text

Abstract: We performed univariate and multivariate discriminant analysis of FDG-PET scans to evaluate their ability to identify Alzheimer's disease (AD). FDG-PET scans came from two sources: 17 AD patients and 33 healthy elderly controls were scanned at the University of Michigan; 102 early AD patients and 20 healthy elderly controls were scanned at the Technical University of Munich, Germany. We selected a derivation sample of 20 AD patients and 20 healthy controls matched on age with the remainder divided into 5 replication samples. The sensitivity and specificity of diagnostic AD-markers and threshold criteria from the derivation sample were determined in the replication samples. Although both univariate and multivariate analyses produced markers with high classification accuracy in the derivation sample, the multivariate marker's diagnostic performance in the replication samples was superior. Further, supplementary analysis showed its performance to be unaffected by the loss of key regions. Multivariate measures of AD utilize the covariance structure of imaging data and provide complementary, clinically relevant information that may be superior to univariate measures.