High density lipoprotein cholesterol and the risk of stroke in elderly men: the Honolulu heart program.

High density lipoprotein (HDL) cholesterol has been inversely associated with coronary heart disease. Associations with stroke are less clear, particularly among the elderly. In this study, the authors examined the relation between HDL cholesterol levels and the risk of stroke in elderly men. Levels of HDL cholesterol were measured in 2,444 Honolulu Heart Program men aged 71-93 years at the 1991-1993 examinations. The participants, who were free of prevalent stroke, coronary heart disease, and cancer at baseline, were followed to the end of 1998 for thromboembolic and hemorrhagic stroke. While HDL cholesterol was unrelated to hemorrhagic events, incidence of thromboembolic stroke declined consistently with increasing HDL cholesterol level (p = 0.003). There was a nearly threefold excess of thromboembolic stroke in men with low HDL cholesterol levels (<1.0 mmol/liter (<40 mg/dl)) compared with men with high levels (> or =1.6 mmol/liter (> or =60 mg/dl)) (10.6/1,000 person-years vs. 3.6/1,000 person-years; p = 0.001). Adjustment for other risk factors had little effect on these findings, although associations appeared strongest in elderly men with "desirable" total cholesterol levels, hypertension, or diabetes mellitus. These findings suggest that HDL cholesterol level is inversely related to the risk of thromboembolic stroke in elderly men. Whether HDL cholesterol alters the effect of other factors on stroke risk in elderly men warrants further study.

Age-related changes in risk factor effects on the incidence of thromboembolic and hemorrhagic stroke.

We examined the changes in risk factor effects on the incidence of thromboembolic and hemorrhagic stroke as they may occur with age. Findings were based on repeated risk factor measurements at four examinations over a 26-year period in 7589 men in the Honolulu Heart Program. After each examination, 6 years of follow-up were available to assess risk factor effects on the incidence of stroke over a broad range of ages (45-93 years). As compared with normotensive men, the risk of thromboembolic stroke in the presence of hypertension declined from a 7-fold excess in men aged 45 to 54 years to a 1.4-fold excess in men aged > or =75 (P<.001). Adverse effects of diabetes and atrial fibrillation seemed to be equally important across all ages, whereas a protective effect of physical activity increased with age. Except for men with atrial fibrillation, the incidence of thromboembolic stroke increased significantly with age regardless of risk factor status, including men with normal blood pressure (P<.001). Although hemorrhagic events were less common, positive relations with cigarette smoking seemed to strengthen with age, whereas those with hypertension tended to decline. Our findings suggest that strategies for the prevention of stroke may need to account for changes in risk factor effects as they occur with age. Control of diabetes and the encouragement of active lifestyles in the elderly seem to be especially important.

C-reactive protein and the future risk of thromboembolic stroke in healthy men.

BACKGROUND: Evidence suggests that C-reactive protein (CRP) is related to thromboembolic (TE) stroke. Whether associations are altered in the presence of other risk factors is unclear. The purpose of this study was to additionally assess the relation between CRP and TE stroke. METHODS AND RESULTS: On the basis of 20 years of follow-up after CRP measurement, 259 cases of TE stroke were identified and compared with 1348 controls. Subjects were aged 48 to 70 years when CRP was measured. Levels of CRP were positively associated with TE stroke throughout the 20 years of follow-up. Although associations were modest within 5 years of CRP measurement, the odds of stroke in the top versus bottom CRP quartile increased over time to a 3.8-fold excess by 10 to 15 years into follow-up (P<0.001). For men without hypertension or diabetes, the overall corresponding odds were 1.6 to 1.7 (P<0.05). In men 55 years of age, and in those with hypertension or diabetes were not significant. CONCLUSIONS: Findings suggest that elevated CRP in middle adulthood and in men with healthier risk factor profiles may be important as a risk factor for TE stroke. Use of CRP levels as a clinical screen to identify an increased risk of cardiovascular disease in otherwise healthy men warrants consideration.

Plantation work and risk of Parkinson disease in a population-based longitudinal study.

CONTEXT: Parkinson disease (PD) has an unknown cause; however, convincing evidence is emerging that indicates pesticides can selectively injure the dopaminergic system in laboratory animals. Retrospective studies in humans demonstrate a link between exposure to agricultural lifestyle factors and PD. OBJECTIVE: To determine whether working on a plantation in Hawaii and exposure to pesticides are associated with an increased risk of PD decades later. DESIGN AND SETTING: Prospective cohort study based on the island of Oahu, Hawaii, with 30 years of follow-up. Years of work on a plantation were assessed by questionnaire at study enrollment in 1965. Self-reported information on pesticide exposure was collected at a separate examination 6 years later. PARTICIPANTS: Participants were 7986 Japanese American men born between 1900 and 1919 who were enrolled in the longitudinal Honolulu Heart Program. MAIN OUTCOME MEASURES: Incident PD was determined by medical record review or by an examination conducted by a study neurologist at a later date. RESULTS: During follow-up, 116 men developed PD. Age-adjusted incidence increased significantly among men who worked more than 10 years on a plantation. The relative risk of PD was 1.0 (95% confidence interval, 0.6-1.6), 1.7 (95% confidence interval, 0.8-3.7), and 1.9 (95% confidence interval, 1.0-3.5) for men who worked on a plantation 1 to 10 years, 11 to 20 years, and more than 20 years compared with men who never did plantation work (P =.006, test for trend). Age-adjusted incidence of PD was higher in men exposed to pesticides than in men not exposed to pesticides although this was not statistically significant (P =.10, test for trend). CONCLUSION: These longitudinal observations regarding plantation work in Hawaii support case-control studies suggesting that exposure to pesticides increases the risk of PD.