What is the ideal blood pressure threshold for the prevention of atrial fibrillation in elderly general population?

Intensive blood pressure (BP) lowering in patients with hypertension at increased risk of cardiovascular disease has been associated with a lowered risk of incident atrial fibrillation (AF). It is uncertain whether maintaining the optimal BP levels can prevent AF in the general elderly population. We included 115,866 participants without AF in the Korea National Health Insurance Service-Senior (≥60 years) cohort from 2002 to 2013. We compared the influence of BP on the occurrence of new-onset AF between octogenarians (≥80 years) and non-octogenarians (<80 years) subjects. With up to 6.7 ± 1.7 years of follow-up, 4393 incident AF cases occurred. After multivariable adjustment for potentially confounding clinical covariates, the risk of AF in non-octogenarians was significantly higher in subjects with BP levels of <120/<80 and ≥140/90 mm Hg, with hazard ratios of 1.15 (95% confidence interval (CI), 1.03–1.28; p < 0.001) and 1.14 (95% CI, 1.04–1.26; p < 0.001), compared to the optimal BP levels (120–129/<80 mm Hg). In octogenarians, the optimal BP range was 130–139/80–89 mm Hg, higher than in non-octogenarians. A U-shaped relationship for the development of incident AF was evident in non-octogenarians, and BP levels of 120–129/<80 mm Hg were associated the lowest risk of incident AF. Compared to non-octogenarians, the lowest risk of AF was associated with higher BP levels of 130–139/80–89 mm Hg amongst octogenarians.