Upper normal blood pressures predict incident atrial fibrillation in healthy middle-aged men: a 35-year follow-up study

Hypertension is the most prevalent risk factor for incident atrial fibrillation (AF). Recently, even high normal blood pressures (BPs) have been established as predictive of AF in women. We aimed to study the long-term impact of upper normal BP on incident AF in a population-based study of middle-aged men. From 1972 to 1975, 2014 healthy Norwegian men were included in a prospective cardiovascular survey and underwent a comprehensive clinical examination including standardized BP measurements. During up to 35 years of follow-up, 270 men were documented with AF by scrutinizing all hospital discharges. Risk estimations for incident AF were analyzed in quartiles of BP using multivariate adjusted Cox proportional hazards. Men with baseline systolic BP ≥140 mm Hg and upper normal BP 128 to 138 mm Hg had 1.60-fold (95% CI 1.15-2.21) and 1.50-fold (1.10-2.03) risk of AF, respectively, compared with men with BP <128 mm Hg. Baseline diastolic BP ≥80 mm Hg increased the risk of incident AF 1.79-fold (95% CI 1.28-2.59) compared with diastolic BP <80 mm Hg. When adjusting for the occurrence of diabetes mellitus or cardiovascular diseases before an AF event, the results still maintained significance. Additional analyses, on average 7 years after baseline, including men still healthy, showed that sustained upper normal systolic BP remained a significant predictor of subsequent AF. In conclusion, upper normal blood pressures are long-term predictors of incident AF in initially healthy middle-aged men.