Annals of Long Term Care

Hypertension and the Risk of Mild Cognitive Impairment

The objective of this study was to explore whether hypertension is associated with the risk of mild cognitive impairment (MCI), an intermediate stage of dementia, because there are conflicting data relating hypertension to the risk of Alzheimer disease. This was a retrospective community-based cohort study conducted in northern Manhattan. Multi-variate proportional hazards regression analyses were used, relating hypertension to incident all-cause MCI, amnestic MCI, and nonamnestic MCI in 918 persons without prevalent MCI at baseline followed up for a mean of 4.7 years.

Results showed that there were 334 cases of incident MCI, 160 cases of amnestic MCI, and 174 cases of nonamnestic MCI during 4337 person-years of follow-up. Hypertension was associated with an increased risk of all-cause MCI (hazard ratio, 1.40; 95% confidence interval, 1.06-1.77; P=.02) and nonamnestic MCI (hazard ratio, 1.70; 95% confidence interval, 1.13-2.42; P=.009) after adjusting for age and sex. Both associations were slightly attenuated in models additionally adjusting for stroke and other vascular risk factors. There was no association between hypertension and the risk of amnestic MCI (hazard ratio, 1.10; 95% confidence interval, 0.79-1.63; P=.49). Consistent with this association, hypertension was related with the slope of change in an executive ability score, but not with memory or language score. There was no effect modification of the association between hypertension and MCI by ApoE4 genotype or use of antihypertensive medication.

The authors concluded that a history of hypertension is related to a higher risk of MCI. The association seems to be stronger with the nonamnestic than the amnestic type of MCI in the elderly. These findings suggest that prevention and treatment of hypertension may have an important impact in lowering the risk of cognitive impairment.

Reitz C, Tang MX, Manly J, et al. Hypertension and the risk of mild cognitive impairment. Arch Neurol 2007;64(12): 1734-1740.

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Physical Activity Recommendations and Decreased Risk of Mortality

Whether national physical activity recommendations are related to mortality benefit is incompletely understood. The authors of this study prospectively examined physical activity guidelines in relation to mortality among 252,925 women and men aged 50 to 71 years in the National Institutes of Health–American Association of Retired Persons (NIH-AARP) Diet and Health Study. Physical activity was assessed using 2 self-administered baseline questionnaires.

Results showed that during 1,265,347 person-years of follow-up, 7900 participants died. Compared with being inactive, achievement of activity levels that approximate the recommendations for moderate activity (at least 30 minutes on most days of the week) or vigorous exercise (at least 20 minutes 3 times per week) was associated with a 27% (relative risk [RR], 0.73; 95% confidence interval [CI], 0.68-0.78) and 32% (RR, 0.68; 95% CI, 0.64-0.73) decreased mortality risk, respectively. Physical activity reflective of meeting both recommendations was related to substantially decreased mortality risk overall (RR, 0.50; 95% CI, 0.46-0.54) and in subgroups, including smokers (RR, 0.48; 95% CI, 0.44-0.53) and nonsmokers (RR, 0.54; 95% CI, 0.45-0.64), normal weight (RR, 0.45; 95% CI, 0.39-0.52) and overweight or obese individuals (RR, 0.48; 95% CI, 0.44-0.54), and those with 2 h/d (RR, 0.53; 95% CI, 0.44-0.63) and more than 2 h/d of television or video watching (RR, 0.50; 95% CI, 0.45-0.55). Engaging in physical activity at less than recommended levels was also related to reduced mortality risk (RR, 0.81; 95% CI, 0.76-0.86).

The authors concluded that following physical activity guidelines is associated with lower risk of death.