Ginette Lafleche

Age at onset of Alzheimer's disease Relation to pattern of cognitive dysfunction and rate of decline

We examined the pattern of cognitive impairment and rate of cognitive and functional decline as a function of age at symptom onset in 127 patients with probable Alzheimers disease (AD). At baseline, early-onset (before age 65) and late-onset groups were mildly and comparably impaired on the modified Mini-Mental State Examination (mMMS) and the Blessed Dementia Rating Scale-Part 1 (BDRS). Repeated-measures analysis of variance revealed significantly more rapid decline in early-onset subjects over a 2-year follow-up period. Multivariate linear regression analyses indicated that age at symptom onset strongly predicted rate of decline on the mMMS and the BDRS, even after controlling for symptom duration, gender, family history of dementia, and baseline mMMS and BDRS scores. Early- and late-onset AD subjects also differed in terms of pattern of performance on the mMMS. Early-onset subjects scored significantly lower than late-onset subjects on attentional items of the mMMS at baseline and follow-up. Conversely, late-onset subjects scored significantly lower than early-onset subjects on memory and naming items at baseline, and the two groups were comparable on these tasks at follow-up. Results provide longitudinal evidence of more rapid cognitive and functional decline in subjects with early-onset AD and suggest that early-onset AD may be characterized by predominant impairment of attentional skills.

Utility of extrapyramidal signs and psychosis as predictors of cognitive and functional decline, nursing home admission, and death in Alzheimer's disease Prospective analyses from the Predictors Study

Objective: To examine whether either extrapyramidal signs or psychotic features are associated with more rapid progression of Alzheimers disease. Background: It has been unclear whether extrapyramidal signs and psychosis are predictors of faster course or are simply late signs. Methods: Two hundred thirty-six patients with mild Alzheimers disease were recruited in three cities and followed semiannually. Results: Using Cox proportional hazards models that adjusted for age, sex, disease severity, and estimated duration of illness at study entry, the presence of extrapyramidal signs at entry was associated with higher relative risk (RR) of reaching moderate cognitive (RR = 2.35, 95% CI = 1.12 to 4.92) or functional (RR = 2.31, 95% CI = 1.37 to 3.90) severity, nursing home entry (RR = 2.51, 95% CI = 1.32 to 4.76), or death (RR = 3.04, 95% CI = 1.31 to 7.05). Psychosis predicted only the functional end point (RR = 1.85, 95% CI = 1.18 to 2.90). Using regression models, modified Mini-Mental State scores declined 1.30 points (95% CI = 0.16 to 2.44) per 6-month interval, more among patients with than those without extrapyramidal signs; patients with psychosis declined 1.15 (95% CI = 0.52 to 1.77) more mMMS points per interval. Conclusions: This study confirms extrapyramidal signs and psychosis as robust predictors of disease end points and rapid progression in Alzheimers disease.

Quality of Life in Patients with Alzheimer's Disease as Reported by Patient Proxies

OBJECTIVE: To measure behaviors indicative of quality of life (QOL) in patients with Alzheimers disease and to examine correlates of patient QOL.

Multicenter study of predictors of disease course in Alzheimer disease (the "predictors study"). I. Study design, cohort description, and intersite comparisons.

Clinicians should be able to provide the patient with Alzheimer disease (AD) and the family with an accurate prediction of what to expect, but the variability in the rate of disease progression precludes this. In several previous studies, specific clinical signs such as muscular rigidity, myoclonus, and hallucinations or delusions were associated with rapid progression to a more severe stage of dementia or death. The “Predictors Study,” a longitudinal study at three independent sites, was designed to develop a predictor model of the natural history of Alzheimer disease. The study was conducted at three study sites, New York, Baltimore, and Boston in a cohort of 224 patients with early probable AD. This article describes the design and implementation of the Predictors Study, and compares features of the study cohort at baseline across sites. Patients were all at the mild stage of disease at entry and were relatively comparable across sites. Extrapyramidal signs and delusions were common, but myoclonus was rarely observed.

Differences in abstraction ability with age.

Three tests of abstraction were administered to 89 optimally healthy subjects aged 30-79. Performance on all 3 tasks showed significant differences with age. This was primarily, although not entirely, the result of deficits in performance by the 70-year-old subjects. These results do not appear to be related to changes in memory ability or to a differential increase in a particular type of abstraction error.

Multicenter Study of Predictors of Disease Course in Alzheimer Disease (the “predictors Study”). Ii. Neurological, Psychiatric, and Demographic Influences on Baseline Measures of Disease Severity

The “Predictors Study” is a prospective cohort study of the natural history of Alzheimer disease (AD), the aim of which is to identify milestones in disease progression and to develop a model to predict disease course in individual patients. The empirical background to this study is based on previous reports that the presence of extrapyramidal signs (EPS), myoclonus, and psychosis in AD may signify greater disease severity at any given stage and a more rapid course of the disease over time. The present analyses were conducted to determine whether these independent “predictor” variables were associated with greater disease severity at baseline within a new cohort of 224 mild AD patients recruited from three different medical centers (in New York, Baltimore, and Boston). Measures of disease severity were provided by the modified Mini-Mental State Examination (mMMSE) and the Blessed Dementia Rating Scale (BDRS), which measures functional capacity. Independent variables were EPS, delusions, and slowing of the posterior dominant EEG rhythm. The frequency of myoclonus and hallucinations was too low to permit adequate statistical assessment of their effects at this time. EPS and EEG slowing were associated with low mMMSE scores, whereas delusions were primarily associated with impaired functional capacity. These effects were independent of the influence of age and disease duration. These results indicate that the effects of these independent variables can be detected at mild stages of AD and that these effects can be generalized across different geographical regions.