Combined effect of blood pressure and physical activity on cardiovascular mortality

BACKGROUND: High blood pressure increases cardiovascular mortality, but whether the effect is counteracted by physical activity is not clear. METHODS: The combined association of blood pressure and physical activity on cardiovascular mortality was assessed in a cohort of 30 597 women and 30 508 men, using standardized blood pressure measurements and information on usual frequency, duration, and intensity of physical exercise. RESULTS: During 16 years of follow-up, 1942 women and 2824 men with no history of cardiovascular disease or diabetes, who had never used blood pressure medication, died from cardiovascular causes. Cardiovascular mortality increased continuously with increasing blood pressure, and, at each blood pressure level, risk was higher in men and women with no physical activity compared with those who reported high physical activity. High activity combined with increasing pressure, however, yielded higher risk than high activity combined with normotensive pressure. Compared with the reference (systolic pressure 120-129 mmHg and high activity), the relative risk of cardiovascular death for systolic pressure of 140-159 mmHg combined with high activity was 1.21 (95% confidence interval, 0.97-1.52), compared with a relative risk of 1.73 (95% confidence interval, 1.37-2.19) in men with no activity. For women, the corresponding relative risks were 1.47 (95% confidence interval, 1.04-2.09) in the high activity group and 1.93 (95% confidence interval, 1.39-2.69) for no activity. The combined results for diastolic pressure and physical activity displayed similar patterns. CONCLUSIONS: The results support the hypothesis that cardiovascular health of individuals with moderate hypertension will benefit from regular physical exercise.