摘要:Objectives: This study was designed to evaluate whether different antihypertensive treatment regimens with similar blood pressure reduction have different effects on new- onset atrial fibrillation(AF). Background: It is unknown whether angiotensin II receptor blockade is better than beta- blockade in preventing new- onset AF. Methods: In the Losartan Intervention For Endpoint reduction in hypertension(LIFE) study 9,193 hypertensive patients and patients with electrocardiogram documented left ventricular hypertrophy were randomized to once- daily losartan or atenolol- based antihypertensive therapy. Electrocardiograms were Minnesota coded centrally, and 8,851 patients without AF by electrocardiogram or history, who were thus at risk of developing AF, were followed for 4.8± 1.0 years. Results: New- onset AF occurred in 150 patients randomized to losartan versus 221 to atenolol(6.8 vs. 10.1 per 1,000 person- years; relative risk 0.67, 95% confidence interval[CI] 0.55 to 0.83, p< 0.001), despite similar blood pressure reduction. Patients receiving losartan tended to stay in sinus rhythm longer(1,809± 225 vs. 1,709± 254 days from baseline, p=0.057) than those receiving atenolol. Moreover, patients with new- onset AF had two- , three- and five- fold increased rates, respectively, of cardiovascular events, stroke, and hospitalization for heart failure. There were fewer composite end points(n=31 vs. 51, hazard ratio=0.60, 95% CI 0.38 to 0.94, p=0.03) and strokes(n=19 vs. 38, hazard ratio=0.49, 95% CI 0.29 to 0.86, p=0.01) in patients who developed new- onset AF in the losartan compared to the atenolol treatment arm of the study. Furthermore, Cox regression analysis showed that losartan(21% risk reduction) and new- onset AF both independently predicted stroke even when adjusting for traditional risk factors. Conclusions: Our novel finding is that new- onset AF and associated stroke were significantly reduced by losartan compared to atenolol- based antihypertensive treatment with similar blood pressure reduction.