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There are conflicting reports about the potential role of vitamin antioxidants in preventing and/or slowing the progression of various forms of cognitive impairment including Alzheimer’s disease (AD). We examined longitudinal data from the Canadian Study of Health and Aging, a population-based, prospective 5-year investigation of the epidemiology of dementia among Canadians aged 65+ years. Our primary objective was to examine the association between supplemental use of antioxidant vitamins and subsequent risk of significant cognitive decline (decrease in 3MS score of 10 points or more) among subjects with no evidence of dementia at baseline (n = 894). We also explored the relationship between vitamin supplement use and incident vascular cognitive impairment (VCI; including a diagnosis of vascular dementia, possible AD with vascular components and VCI but not dementia), dementia (all cases) and AD. After adjusting for potential confounding factors assessed at baseline, subjects reporting a combined use of vitamin E and C supplements and/or multivitamin consumption at baseline were significantly less likely (adjusted OR 0.51; 95% CI 0.29–0.90) to experience significant cognitive decline during a 5-year follow-up period. Subjects reporting any antioxidant vitamin use at baseline also showed a significantly lower risk for incident VCI (adjusted OR 0.34, 95% CI 0.13–0.89). A reduced risk for incident dementia or AD was not observed. Our findings suggest a possible protective effect for antioxidant vitamins in relation to cognitive decline but randomized controlled trials are required for confirmation.

Objectives: To determine whether baseline self-rated health (SRH) independently predicted survival in an older Canadian population and to investigate the role of cognition on the SRH-mortality relationship. Design: Population-based prospective cohort study. Setting: Ten Canadian provinces, community-based. Participants: A total of 8,697 community-dwelling participants aged 65 and older. Measurements: Self-reported measures of overall health, physical function, comorbidities, and demographic characteristics were obtained by interview. Cognitive ability was ascertained using the Modified Mini-Mental State Examination (3MS). Participants were followed for their survival status from the initial interview in 1991 until October 31, 1996. Results: Subjects with reports of poor SRH were significantly more likely to die during follow-up than those reporting good SRH, after adjusting for relevant covariates (adjusted hazard ratio (AHR)=1.38, 95% confidence interval (CI)=1.24–1.53). SRH was also related to other measures of health status across levels of cognitive impairment. SRH remained a significant predictor of mortality in subjects with mild to moderate cognitive impairment (AHR=1.26, 95% CI=1.01–1.59) but not in those with severe cognitive impairment (AHR=1.00, 95% CI=0.76–1.31). Conclusion: This study supports the utility of SRH assessments in predicting survival of individuals with mild to moderate cognitive impairment. The findings highlight the potential role of complex cognitive processes underlying the SRH-mortality relationship.

Purpose This study examines the risk of all-cause and cardiac-related mortality associated with calcium channel blockers (CCBs) and other antihypertensives/diuretics compared with β-blockers among an elderly cohort. We explored variations in mortality risk according to CCB formulation, dose and duration of use. Methods Data are from the clinical sample of the Canadian Study of Health and Aging, a population-based prospective study of community and institutional residing persons aged 65+ years. The sample comprised 837 subjects without dementia and reporting use of 1+ antihypertensive/diuretic agents at baseline (1991) and with survival data during follow-up (1996). Results Risk of all-cause and cardiac-related mortality was significantly higher among nifedipine users (HR=1.85, 95%CI 1.12, 3.05 and HR=2.22, 95%CI 1.02, 4.84, respectively) compared with β-blocker users. After adjusting for covariates, the hazard ratios (95% confidence interval) for selected drug classes compared with β-blockers were: nifedipine HR=1.82 (1.09–3.04), diltiazem/verapamil HR=0.96 (0.58–1.60), loop diuretics HR=1.84 (1.21–2.82), ACE inhibitors HR=0.98 (0.54–1.78) and other diuretics/antihypertensives HR=1.10 (0.70–1.72). Among nifedipine users, mortality risk increased with average daily dose and with recent (≤6 months) initiation of therapy and remained significant for prolonged-acting formulations. Conclusions Older subjects exposed to the dihydropyridine calcium antagonist nifedipine had a significantly higher risk for all-cause and cardiac-related mortality during the 5-year follow-up than subjects using β-blockers. Copyright © 2000 John Wiley & Sons, Ltd.

Data collected as part of the Canadian Study of Health and Aging were analyzed to determine whether physiological changes associated with Alzheimer's disease are common to other types of dementia and are related more to the severity of cognitive impairment. We found that blood pressure and body mass index decreased with increasing dementia severity in both probable Alzheimer's disease and vascular dementia. There were no differences in mean random blood glucose levels or serum osmolarities between types or stages of dementia. We conclude that certain 'hypometabolic' features are associated with dementia severity and are not unique to Alzheimer's disease.

We report on the prevalence of primitive reflexes (PR) and their association with cognitive, behavioural, functional and clinical characteristics in 2914 Canadians 65 years and older. Data were collected as part of the Canadian Study of Health and Aging (1990-92) and included individuals living in the community and in institutions. PR were more commonly found in demented subjects. Demented subjects with prehensile PR (i.e. grasp, traction, suck) had significantly more functional and behavioural problems and were more severely demented. The presence of any PR increased the likelihood of other neurological findings (e.g. bradykinesia). Vascular dementia (VD) cases were more likely to have unilateral primitive PR than probable Alzheimer's disease (Pro AD) and Parkinson's dementia (PD) cases. PD cases were more likely to have glabellar and traction responses. While more common among the demented, PR lacked sufficient sensitivity to be an early diagnostic tool for dementia. Prehensile PR may help to define particular types or severity of dementia.

To determine whether baseline self-rated health (SRH) independently predicted survival in an older Canadian population and to investigate the role of cognition on the SRH-mortality relationship.Population-based prospective cohort study.Ten Canadian provinces, community-based.A total of 8,697 community-dwelling participants aged 65 and older.Self-reported measures of overall health, physical function, comorbidities, and demographic characteristics were obtained by interview. Cognitive ability was ascertained using the Modified Mini-Mental State Examination (3MS). Participants were followed for their survival status from the initial interview in 1991 until October 31, 1996.Subjects with reports of poor SRH were significantly more likely to die during follow-up than those reporting good SRH, after adjusting for relevant covariates (adjusted hazard ratio (AHR)=1.38, 95% confidence interval (CI)=1.24-1.53). SRH was also related to other measures of health status across levels of cognitive impairment. SRH remained a significant predictor of mortality in subjects with mild to moderate cognitive impairment (AHR=1.26, 95% CI=1.01-1.59) but not in those with severe cognitive impairment (AHR=1.00, 95% CI=0.76-1.31).This study supports the utility of SRH assessments in predicting survival of individuals with mild to moderate cognitive impairment. The findings highlight the potential role of complex cognitive processes underlying the SRH-mortality relationship.

Recent epidemiologic studies have shown an association between low serum folate levels and risk of vascular disease, including stroke and various types of vascular cognitive impairment. We examined data from the Canadian Study of Health and Aging (CSHA), a population-based, prospective 5-year investigation of the epidemiology of dementia among Canadians aged 65+ years. The risk of an adverse cerebrovascular event (including vascular dementia, vascular cognitive impairment, or fatal stroke) during follow-up, was assessed according to serum folate quartiles among subjects with no evidence of dementia at baseline (n = 369). After adjusting for certain covariates, including cardiovascular disease and nutritional indices, education, smoking and baseline cognitive status, the risk estimate for an adverse cerebrovascular event associated with the lowest folate quartile compared with the highest quartile was OR 2.42 (95% CI 1.04–5.61). Results from stratified analyses also showed that relatively low serum folate was associated with a significantly higher risk of an adverse cerebrovascular event among female (OR 4.02, 95% CI 1.37–11.81) but not male (OR 1.02, 95% CI 0.25–4.13) subjects. Among the total sample, there was a consistent trend toward poorer health and cognitive outcomes during follow-up (including mortality, cognitive decline and dementia) among those in the lowest folate quartile compared with the highest quartile. Low serum folate levels are independently associated with a significantly higher risk of an adverse cerebrovascular event, including vascular dementia and stroke death, among older, cognitively vulnerable persons.