Elevated midlife blood pressure increases stroke risk in elderly persons: the Framingham Study

Area of Science:

• Cardiovascular Epidemiology
• Neurology
• Preventive Medicine

Background:

• Traditional stroke risk prediction relies on current blood pressure (BP).
• The influence of a person's past BP readings (antecedent BP) on future stroke risk is not well understood.
• This study investigates the additional predictive value of antecedent BP for ischemic stroke risk.

Purpose of the Study:

• To determine the incremental impact of antecedent blood pressure on the risk of ischemic stroke.
• To assess whether past BP measurements provide additional predictive information beyond current BP levels for stroke risk.

Main Methods:

• Analysis of 5197 stroke-free participants from the Framingham Study cohort (1948-1998).
• Calculation of 10-year ischemic stroke risk for 60-, 70-, and 80-year-olds based on current, recent (1-9 years prior), and remote (10-19 years prior) antecedent BP.
• Statistical adjustments for smoking, diabetes mellitus, and baseline BP.

Main Results:

• Antecedent BP significantly influenced 10-year ischemic stroke risk at ages 60 and 70.
• Increased risk was observed per standard deviation increment in recent antecedent systolic BP for both women and men.
• This effect was consistent across recent and remote antecedent BP, in hypertensive and non-hypertensive individuals, and for all BP components.

Conclusions:

• Past blood pressure experience (antecedent BP) is a significant contributor to future ischemic stroke risk.
• Effective prevention of stroke in later life necessitates the management of blood pressure during midlife.