Blood pressure and mortality risk in older people: comparison between African Americans and whites.

OBJECTIVES

To determine the risk from hypertension for all-cause mortality in a racially mixed sample of community-dwelling older adults.

DESIGN

Baseline blood pressure was assessed between 1985 and 1986 in a sample of persons 65 years of age and older from five counties of the Piedmont of North Carolina (N = 4,162). All-cause mortality was monitored annually over the subsequent 6 years as part of the Established Populations for Epidemiologic Studies of the Elderly (EPESE) sponsored by the National Institute on Aging.

SETTING

Eighteen percent of all respondents in the sample had a systolic blood pressure of > 160 (17% for whites and 18% for African Americans) and 16% had a diastolic blood pressure of >90 (14% for whites and 20% for African Americans). During the 6 years of follow-up, 29% of the sample died (with no difference in mortality rates between whites and African Americans).

PARTICIPANTS

4,000 community-dwelling people age 65 years and older; 1,846 were white and 2,154 were African American.

MEASUREMENTS

Systolic and diastolic blood pressure and all-cause mortality.

RESULTS

Systolic blood pressure positively related to mortality during the 6 years of follow-up (relative risk = 1.05). Among whites the relationship of diastolic pressure to mortality was nonlinear, with those at the upper and lower ends of the distribution at increased risk. Among African Americans, diastolic pressure was unrelated to mortality. The analyses were controlled for age; gender; education; body mass index (BMI); smoking history; taking a medication to manage blood pressure; a history of cancer, diabetes mellitus, heart attack, or stroke; poor subjective health; impaired functional status; and cognitive impairment.

CONCLUSIONS

The findings confirm that among older adults there is a significant relationship overall between systolic blood pressure and mortality over 6 years of follow-up in both whites and African Americans. Diastolic pressure was a risk factor for whites only.