Showing papers by "Lisa L. Barnes published in 2002"

Participation in Cognitively Stimulating Activities and Risk of Incident Alzheimer Disease

Abstract: ContextFrequent participation in cognitively stimulating activities has been hypothesized to reduce risk of Alzheimer disease (AD), but prospective data regarding an association are lacking.ObjectiveTo test the hypothesis that frequent participation in cognitive activities is associated with a reduced risk of AD.DesignLongitudinal cohort study with baseline evaluations performed between January 1994 and July 2001 and mean follow-up of 4.5 years.Participants and SettingA total of 801 older Catholic nuns, priests, and brothers without dementia at enrollment, recruited from 40 groups across the United States. At baseline, they rated frequency of participation in common cognitive activities (eg, reading a newspaper), from which a previously validated composite measure of cognitive activity frequency was derived.Main Outcome MeasuresClinical diagnosis of AD by a board-certified neurologist using National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association criteria and change in global and specific measures of cognitive function, compared by cognitive activity score at baseline.ResultsBaseline scores on the composite measure of cognitive activity ranged from 1.57 to 4.71 (mean, 3.57; SD, 0.55), with higher scores indicating more frequent activity. During an average of 4.5 years of follow-up, 111 persons developed AD. In a proportional hazards model that controlled for age, sex, and education, a 1-point increase in cognitive activity score was associated with a 33% reduction in risk of AD (hazard ratio, 0.67; 95% confidence interval, 0.49-0.92). Results were comparable when persons with memory impairment at baseline were excluded and when terms for the apolipoprotein E ∊4 allele and other medical conditions were added. In random-effects models that controlled for age, sex, education, and baseline level of cognitive function, a 1-point increase in cognitive activity was associated with reduced decline in global cognition (by 47%), working memory (by 60%), and perceptual speed (by 30%).ConclusionThese results suggest that frequent participation in cognitively stimulating activities is associated with reduced risk of AD.

Natural history of mild cognitive impairment in older persons.

Abstract: Background: Cognitive abilities of older persons range from normal, to mild cognitive impairment, to dementia. Few large longitudinal studies have compared the natural history of mild cognitive impairment with similar persons without cognitive impairment. Methods: Participants were older Catholic clergy without dementia, 211 with mild cognitive impairment and 587 without cognitive impairment, who underwent annual clinical evaluation for AD and an assessment of different cognitive abilities. Cognitive performance tests were summarized to yield a composite measure of global cognitive function and separate summary measures of episodic memory, semantic memory, working memory, perceptual speed, and visuospatial ability. The authors compared the risk of death, risk of incident AD, and rates of change in global cognition and different cognitive domains among persons with mild cognitive impairment to those without cognitive impairment. All models controlled for age, sex, and education. Results: On average, persons with mild cognitive impairment had significantly lower scores at baseline in all cognitive domains. Over an average of 4.5 years of follow-up, 30% of persons with mild cognitive impairment died, a rate 1.7 times higher than those without cognitive impairment (95% CI, 1.2 to 2.5). In addition, 64 (34%) persons with mild cognitive impairment developed AD, a rate 3.1 times higher than those without cognitive impairment (95% CI, 2.1 to 4.5). Finally, persons with mild cognitive impairment declined significantly faster on measures of episodic memory, semantic memory, and perceptual speed, but not on measures of working memory or visuospatial ability, as compared with persons without cognitive impairment. Conclusions: Mild cognitive impairment is associated with an increased risk of death and incident AD, and a greater rate of decline in selected cognitive abilities.

Individual differences in rates of change in cognitive abilities of older persons

Abstract: The authors examined change in cognitive abilities in older Catholic clergy members. For up to 6 years, participants underwent annual clinical evaluations, which included a battery of tests from which summary measures of 7 abilities were derived. On average, decline occurred in each ability and was more rapid in older persons than in younger persons. However, wide individual differences were evident at all ages. Rate of change in a given domain was not strongly related to baseline level of function in that domain but was moderately associated with rates of change in other cognitive domains. The results suggest that change in cognitive function in old age primarily reflects person-specific factors rather than an inevitable developmental process.

Depressive symptoms, cognitive decline, and risk of AD in older persons

Abstract: Background : Cross-sectional and retrospective case-control studies suggest an association of depression symptoms with cognitive impairment and AD, but there have been few prospective studies and their results have been inconsistent. Methods : Participants are Catholic clergy members who were aged ≥65 years and who did not have clinical evidence of AD. During a 7-year period, they underwent annual clinical evaluations that included clinical classification of AD and detailed cognitive function testing from which global and specific measures of cognition were derived. Number of depressive symptoms was assessed at baseline with a modified, 10-item Center for Epidemiologic Studies Depression Scale (CES-D). The association of CES-D score with incident AD, using proportional hazards models, and cognitive decline, using random effects models, was examined. Results : At baseline, participants reported an average of about one depressive symptom on the CES-D scale (range, 0 to 8). During the 7 years of follow-up, 108 persons developed AD. In analyses that controlled for selected demographic and clinical variables including baseline level of cognitive function, CES-D score was associated with both risk of AD and rate of cognitive decline. For each depressive symptom, risk of developing AD increased by an average of 19%, and annual decline on a global cognitive measure increased by an average of 24%. Conclusions : The results raise the possibility that depressive symptoms in older persons may be associated with risk of developing AD.

The apolipoprotein E epsilon 4 allele and decline in different cognitive systems during a 6-year period.

Abstract: Context Impairment of episodic memory is an early and defining feature of Alzheimer disease (AD). The apolipoprotein E (APOE) ϵ4 allele is known to influence risk of AD but it has been difficult to establish whether it affects episodic memory differently from other cognitive functions. Objective To examine the association of ϵ4 with decline in different cognitive systems. Design Longitudinal cohort study. Setting More than 40 groups of Catholic clergy from across the United States. Participants Older Catholic clergy members without clinical evidence of dementia at baseline underwent annual clinical evaluations for up to 6 years. Of 624 persons eligible for follow-up, 611 (98%) participated, of whom 161 (26%) had at least 1 ϵ4 allele. They completed an average of 5.5 evaluations (range, 2-7). Main Outcome Measures Incident AD and annual rates of change in episodic memory, semantic memory, working memory, perceptual speed, and visuospatial ability. Results The presence of ϵ4 was associated with risk of developing AD on follow-up (relative risk, 1.92; 95% confidence interval, 1.27-2.89). In a series of random effects models, ϵ4 was associated with impaired baseline function in episodic memory and visuospatial ability and with more rapid decline in all domains. The effect of ϵ4 on annual decline in episodic memory (>3-fold increase) was significantly stronger than its effect on decline in other cognitive systems ( P P = .06). Conclusion The results suggest that the APOE ϵ4 allele influences risk of AD by a relatively selective effect on episodic memory.