Blood pressure increase between 55 and 68 years of age is inversely related to lung function: longitudinal results from the cohort study 'Men born in 1914'.

BACKGROUND: Although age is associated with increasing blood pressure, there is a substantial heterogeneity within a certain birth cohort. Whether increase in systolic and diastolic blood pressure is related to pulmonary function is largely unknown. OBJECTIVE: To study blood pressure elevation between 55 and 68 years of age in relation to vital capacity (VC) and forced expiratory volume (FEV1.0) at 55. DESIGN: Population-based cohort study. PARTICIPANTS: A total of 375 men without antihypertensive medication at baseline. MAIN OUTCOME MEASURE: Change in systolic blood pressure (SBP) and diastolic blood pressure (DBP) over 13 years. RESULTS: Blood pressure increase between 55 and 68 years was highest among men who at 55 years had low vital capacity. Average increase in systolic blood pressure for men with vital capacity in the first, second, third and fourth quartile was 20.4, 18.7, 16.5 and 11.1 mmHg, respectively (P for trend = 0.005). Average increase in diastolic blood pressure was 10.6, 9.9, 9.0 and 6.3 mmHg, respectively (P= 0.02). The trends remained statistically significant after adjustments for baseline blood pressure, tobacco consumption, smoking cessation between 55 and 68, weight change between 55 and 68, physical activity and diabetes. Further analysis showed that the relationships could be found among men with blood pressures < or = 140/ 90 mmHg at baseline, whereas no significant association was found for men whose baseline SBP or DBP exceeded 140/90 mmHg. FEV1.0 showed similar associations with change in blood pressure. CONCLUSION: Lung function is inversely associated with future blood pressure increase. It is suggested that this association could contribute to the relationships between lung function and incidence of cardiovascular disease.