Objective: To evaluate the relationship between the ankle/arm blood pressure index (AAI, the ratio of ankle to arm systolic blood pressure, a measure of peripheral arterial disease) and short-term cardiovascular morbidity and mortality in older adults with systolic hypertension.
Design: Prospective cohort study, 1- to 2-year follow-up (mean, 16 months).
Setting: Eleven of 16 field centers from the Systolic Hypertension in the Elderly Program.
Participants: 1537 older men and women with systolic hypertension.
Main outcome measures: All-cause mortality, coronary heart disease (CHD) mortality, cardiovascular disease (CVD) mortality, and CHD and CVD morbidity and mortality.
Results: The AAI was measured at the 1989-1990 clinic examination and was 0.9 or less in 25.5% of 1537 participants. A low AAI was associated with most major CHD and CVD risk factors. In those with a low AAI (< or = 0.9) compared with those with an AAI of more than 0.9, age- and sex-adjusted relative risks for mortality end points at follow-up were as follows: total mortality, 3.8 (95% confidence interval [CI], 2.1 to 6.9); CHD mortality, 3.24 (95% CI, 1.4 to 7.5); and CVD mortality, 3.7 (95% CI, 1.8 to 7.7). For CVD morbidity and mortality, the age- and sex-adjusted relative risk was 2.5 (95% CI, 1.5 to 4.3). After adjustment for baseline CVD and other cardiovascular risk factors, the relative risk for total mortality was 4.1 (95% CI, 2.0 to 8.3) and for CVD morbidity and mortality, 2.4 (95% CI, 1.3 to 4.4). Results were similar when participants with clinical CVD at baseline were excluded.
Conclusion: A low AAI appears to be an important predictor of morbidity and mortality among older adults with systolic hypertension.