Effect of Intensive Blood Pressure Lowering on Incident Atrial Fibrillation and P-Wave Indices in the ACCORD Blood Pressure Trial

BACKGROUND There are no proven strategies to prevent atrial fibrillation (AF) in patients with type 2 diabetes (T2DM). We compared standard blood pressure (BP) lowering vs. intensive BP lowering in reducing incidence of AF or P-wave indices (PWI - ECG markers of left atrial abnormality that are considered intermediate phenotypes of AF) in patients with T2DM. METHODS We analyzed data from the ACCORD BP trial - a randomized controlled nonblinded trial (2001-2009) which randomized patients with T2DM and systolic BP (SBP) 130-180mm Hg on ≤3 antihypertensive medications aged 40-79 years with cardiovascular disease (CVD) or aged 55-79 years with subclinical CVD or ≥2 CVD risk factors to standard BP lowering (SBP <140mm Hg) vs. intensive BP lowering (SBP <120mm Hg). The primary outcome was a composite of incident AF and PWI. RESULTS Data from 3,087 participants (mean age, 62.2 years; women, 48.2%; non-White, 39.2%) were analyzed. During a mean follow-up of 4.4 years, the primary outcome occurred in 1,063 participants (incidence rate, 84.5 per 1,000 person-years in the standard-therapy group vs. 73.9 per 1,000 person-years in the intensive-therapy group). The adjusted hazard ratios (95% confidence intervals) of intensive-therapy group for the primary outcome and for incident PWI alone were 0.87 (0.77-0.98), P = 0.02 and 0.87 (0.76-0.98), P = 0.02, respectively. The effect of intensive therapy on the incidence of AF alone did not reach statistical significance. CONCLUSIONS In patients with T2DM, intensive BP lowering reduces the incidence of the composite outcome of AF and PWI, suggesting a potential benefit from stringent BP control in patients with T2DM.