Blood pressure, smoking and body mass in relation to mortality from strokeand coronary heart disease in the elderly. A 10-year follow-up in Norway

Objectives: To examine the association between blood pressure, smoking and body mass index (BMI) and cerebro- and cardiovascular mortality in a popula tion of healthy elderly. Design: Ten-year mortality follow-up of elderly me n and women who participated in the Nord-Trondelag Health Study 1984-86. Se tting: Nord-Trondelag county, Norway. Subjects: 3121 men and 3271 women age d 70 years and older, free from any diagnosed atherosclerotic diseases or d iabetes at baseline. Main outcome measures: Relative risk of cerebro- and c ardiovascular mortality and all-cause mortality according to blood pressure , smoking and BMI. Results: There was a consistent, positive association be tween systolic and diastolic blood pressure and cerebro- and cardiovascular mortality. The association persisted after adjustment for potential confou nding factors, and was strongest for cerebrovascular mortality; the adjuste d relative risks for systolic blood pressure categories 160-179 mmHg and gr eater than or equal to 180 mmHg in men were 1.63 (95% confidence interval, CI 1.06-2.53) and 2.19 (95% CI 1.39-3.44) compared to blood pressure < 140 mmHg. In women, the corresponding relative risks were 1.54 (95% Cl 0.93-2.5 6) and 2.12 (95% CI 1.29-3.50). For diastolic blood pressure the adjusted r elative risks in categories 100-109 and greater than or equal to 110 mmHg i n men were 1.88 (95% CI 1.19-2.95) and 3.06 (95% CI 1.79-5.21) compared to pressure < 90 mmHg. The corresponding relative risks in women were 1.75 (95 % Cl 1.05-2.91) and 2.02 (95% CI 1.04-3.93). Current smoking increased card iovascular mortality in both men and women, and among women, BMI was negati vely associated with all-cause mortality. Conclusions: These findings add t o the growing evidence that hypertension is a major risk factor for mortali ty from stroke and coronary heart disease among the elderly and the very ol d.