An epidemiological study found that patients treated for hypertension with beta-blockers, ACE-inhibitors or angiotensin-2 receptor blockers (ARBs) had a lower risk of atrial fibrillation (AF) than those treated with calcium-channel blockers (CCBs).

Hypertension is a risk factor for AF, and treatment with antihypertensive drugs reduces this risk. There is evidence that ACE-inhibitors and ARBs may have additional effects in reducing risk of AF, but opinions conflict and there are no data from studies comparing more than two drug classes. This study used data from the UK GPRD, a well-validated database comprising approximately 5 million UK primary care patient records, to analyse risk of AF in patients receiving monotherapy (or monotherapy with low-dose diuretic) with several drug classes. For the study population, the authors extracted details of treated hypertensive patients who had received one or more prescriptions for an ACE-inhibitor, ARB, beta-blocker, CCB, or diuretic. Those with a diagnosis of AF without clinical risk factors were identified and each was matched with four controls from the study population. The authors then carried out a nested case-control analysis to assess and compare the relative risk for incident AF according to drug class, using CCB as a reference group.

There were 682,993 patients treated for hypertension in the study population; 4,661 had a diagnosis of AF and were matched with 18,642 controls. Compared with those receiving CCB, current long-term recipients of ACE inhibitors had a lower risk of AF (adjusted odds ration [OR], 0.75; 95% CI, 0.65 to 0.87), as did those treated with ARB (adjusted OR, 0.71; 95% CI, 0.57 to 0.89) In addition, those who had been receiving beta-blockers for the past year or longer also had a reduced risk (adjusted OR, 0.78; 95% CI, 0.67 to 0.92).

The authors conclude that in patients with hypertension, long-term treatment with ACE inhibitors, ARBs, or beta-blockers reduces the risk for AF compared with CCB treatment. They note some limitations of their study, including the inclusion of patients being treated with diuretics (to avoid excluding the many patients on diuretic combinations) and the possibility of selection bias. They therefore suggest that confirmatory research is needed.