Cross-sectional Association Between Blood Pressure Status and Atrial Fibrillation in an Elderly Chinese Population

OBJECTIVE Atrial fibrillation (AF) and hypertension are prevalent chronic disease conditions in the elderly population. In the present cross-sectional study, we investigated the association between blood pressure (BP) and AF in an elderly Chinese population. METHOD Our elderly (≥65 years) subjects were residents recruited from 6 communities in Shanghai from 2006 to 2017. Atrial fibrillation was systematically screened by rest 12-lead electrocardiogram (ECG) or by a handheld single-lead ECG. BP status was defined according to the European hypertension guidelines as optimal, normal, or high-normal BP, and stage 1, 2, or 3 hypertension. RESULT In the 6,966 participants (women 56.0%, mean age: 72.3 years), the prevalence of AF was 3.3%, and the prevalence of hypertension was 58.7% (83.7% treated). In all participants, the association with prevalent AF was negative for systolic BP (odds ratio [OR] per 10-mm Hg increase 0.79, 95% confidence interval [CI]: 0.71–0.88, P < 0.0001) but positive for diastolic BP (OR per 5-mm Hg increase 1.11, 95% CI: 1.02–1.22, P = 0.02). In untreated participants (n = 3,544), the association with prevalent AF was U-shaped for both systolic and diastolic BP, with the nadir at high-normal BP and a significantly higher risk of prevalent AF in optimal systolic BP (OR: 3.11, 95% CI: 1.65–5.85, P = 0.004) and stage 2 or 3 diastolic hypertension relative to the nadir (OR: 8.04, 95% CI: 2.28–28.3, P = 0.001). CONCLUSION In the elderly population, BP shows a complicated relationship with prevalent AF, with high-normal BP at the lowest risk and optimal systolic BP and stage 2 or 3 diastolic hypertension at increased risks.