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.