Blood pressure and disability-free survival among community-dwelling diabetic and non-diabetic elderly patients receiving antihypertensive treatment.

Abstract

Although many large-scale trials showed efficacies of antihypertensive treatment in patients with diabetes mellitus and hypertension for reduction of cardiovascular (CV) morbidity/mortality, blood pressure (BP) targets in older hypertensive patients with diabetes still represent the object of debate. We investigated adequate BP targets with respect to the risk of incident disability or mortality in community-dwelling elderly hypertensive patients with and without diabetes. We analyzed 139 diabetic and 431 non-diabetic patients receiving antihypertensive treatment aged 65 years or older. The end-point was the composite outcome of first certification for support/care need or mortality. Relationships among each of four classes of systolic BP (SBP) or diastolic BP (DBP) and the risk of events were estimated using Cox hazards analysis. Over 4 years, diabetic patients showed significantly higher rates of all events including first certification for support/care need or mortality compared with the non-diabetic subjects (29 [20.8%] and 48 [11.1%] cases, unadjusted hazard ratio [HR] 1.99, 95% confidence interval (CI) 1.26-3.16, P = 0.003). After adjustment for confounding variables, the risk of events was significantly higher in non-diabetic subjects with SBP <120 mmHg (HR 3.90, 95% CI 1.32-11.5, P = 0.014) and SBP ≥160 mmHg (HR 3.42, 95% CI 1.22-9.57, P = 0.019), but only those with SBP ≥160 mmHg (HR 22.8, 95% CI 4.83-118, P < 0.001) in diabetic patients, compared with non-diabetic control subjects with baseline SBP of 140-159 mmHg. These observations showed the critical importance of intensive control of SBP to <160 mmHg for disability-free survival in elderly hypertensive patients with diabetes mellitus.