In a population-based prospective study, no association between high blood pressure and mortality after age 85 years

OBJECTIVE: To study the impact of a history of hypertension and current blood pressure on mortality in the oldest old. DESIGN: An observational population-based cohort study. SETTING: Community city of Leiden, The Netherlands. PARTICIPANTS: Five hundred and ninety-nine inhabitants of the birth-cohort 1912-1914 were enrolled on their 85th birthday. There were no selection criteria related to health or demographic characteristics. INTERVENTIONS: The mean follow-up was 4.2 years. Medical histories were obtained from general practitioners. Medication histories were obtained from the participant's pharmacist. Blood pressure was measured twice at baseline. MAIN OUTCOME MEASURES: All cause and cardiovascular mortality. RESULTS: Five hundred and seventy-one participants were included, 39.2% had a history of hypertension. During follow-up 290 participants died, 119 due to cardiovascular causes. Compared to participants without a history of hypertension, those with a history of hypertension had increased mortality from cardiovascular causes relative risk (RR) 1.60, confidence interval (CI) 1.06-2.40 but equal mortality from all causes (RR 1.19, CI 0.91-1.55). High blood pressure at baseline (age 85) was not a risk factor for mortality. Baseline blood pressure values below 140/70 mmHg (n = 48) were associated with excess mortality, predominantly in participants with a history of hypertension. CONCLUSION: In the oldest old, high blood pressure is not a risk factor for mortality, irrespective of a history of hypertension. Blood pressure values below 140/70 mmHg are associated with excess mortality.