Objectives: To establish the relationship between childhood mental ability and adult hypertension.
Design: Retrospective cohort study.
Setting: Community.
Participants: Non-clinical sample of people born in 1921 who participated in both the Scottish Mental Survey 1932 and the Midspan studies. Nine hundred and thirty-eight people were participants in both studies.
Main outcome measures: Mid-life systolic and diastolic blood pressure, intelligence quotient (IQ) at age 11 years, sex, social class, height and weight.
Results: After adjustment for age, sex, social class, body mass index, height, cholesterol level and smoking, there remained a 3.15 mmHg decrease in systolic blood pressure and a 1.5 mmHg decrease in diastolic blood pressure for each standard deviation increase in childhood IQ.
Conclusions: The association between hypertension and lower cognitive function in adulthood is partly accounted for by individual differences in childhood IQ.