The study authors, Led by Dr. Anushka Patel, of Royal Prince Alfred Hospital in Sydney, Australia,examined 11,000 patients with type 2 diabetes to find mortality and cardiovascular risks associated with atrial fibrillation. They also planned to determine whether the effects of blood pressure lowering on cardiovascular events differ between diabetics with and without atrial fibrillation.

The researchers randomly assigned study subjects to a fixed combination of perindopril and indapamide or placebo. At baseline, atrial fibrillation was seen in 847 patients (7.6%). Over 4.3 years of mean follow-up, 879 patients died, with 53% of the deaths due to cardiovascular causes.

According to the article, 15% of the deaths occurred in patients with atrial fibrillation. After multiple adjustments, associations were observed between atrial fibrillation and increased risks of all-cause mortality (hazard ratio [HR] 1.61; p < 0.0001), cardiovascular death (HR 1.77; p < 0.0001), and death from heart failure (HR 1.68; p = 0.0002). Patients with atrial fibrillation also had a higher risk of major cerebrovascular events (HR 1.68; p = 0.0008).

Routine blood pressure lowering using a fixed combination of perindopril-indapamide produced similar relative risk reductions in cardiovascular and all-cause mortality in patients with and without atrial fibrillation, the investigators report. However, they add, because of their higher risks of these events, the absolute benefits of this blood pressure-lowering treatment appear much greater in patients with atrial fibrillation.

According to researchers, 5 years of active blood pressure lowering treatment would prevent death in one out of every 39 patients with atrial fibrillation or out of 84 patients without the arrhythmia. Prevention of one cardiovascular death needs treatment for 5 years in 42 patients with atrial fibrillation versus 120 patients without it.