OBJECTIVE To investigate the effects of alcohol abstinence on prevention of new-onset atrial fibrillation (AF) in patients with type 2 diabetes mellitus (T2DM).

RESEARCH DESIGN AND METHODS A total of 1,112,682 patients newly diagnosed with T2DM between 2011 and 2014 were identified from the Korean National Health Insurance Service database. After excluding those with a history of AF, 175,100 patients were included. The primary outcome was new-onset AF.

RESULTS During a mean follow-up of 4.0 years, AF occurred in 4,174 patients. Those with heavy alcohol consumption (alcohol intake ≥40 g/day) before T2DM diagnosis had a higher risk of AF (adjusted hazard ratio [aHR] 1.22; 95% CI 1.06-1.41) compared with patients with no alcohol consumption. After T2DM diagnosis, those with moderate to heavy alcohol consumption (alcohol intake ≥20 g/day) who abstained from alcohol had a lower risk of AF (aHR 0.81; 95% CI 0.68-0.97) compared with constant drinkers. Alcohol abstinence showed consistent trends toward lower incident AF in all subgroups and was statistically significant in men (aHR 0.80; 95% CI 0.67-0.96), those aged >65 years (aHR 0.69; 95% CI 0.52-0.91), those with CHA₂DS₂-VASc score <3 points (aHR 0.71; 95% CI 0.59-0.86), noninsulin users (aHR 0.77; 95% CI 0.63-0.94), and those with BMI <25 kg/m² (aHR 0.68; 95% CI 0.53-0.88).

CONCLUSIONS In patients with newly diagnosed T2DM, alcohol abstinence was associated with a low risk of AF development. Lifestyle modifications, such as alcohol abstinence, in patients newly diagnosed with T2DM should be recommended to reduce the risk of AF.