Results from a large, international, randomised, controlled trial have shown that there is a strong link between patients with diabetes mellitus who have atrial fibrillation and an increased risk of other heart-related problems and death.
The findings are published in the European Heart Journal.
The ADVANCE study of 11,140 patients with type 2 diabetes found that patients who had atrial fibrillation at the start of the trial had a 61% increased risk of dying from any cause, a 77% increased risk of dying from cardiovascular causes such as a myocardial infarction or stroke, and a 68% increased risk of developing heart failure or other cerebrovascular problems such as stroke, when compared with diabetic patients who did not have atrial fibrillation.
However, the study also found that if clinicians gave more aggressive treatments to the diabetic atrial fibrillation patients, in this study they treated them with a combination blood pressure lowering drugs, ( Perindopril and Indapamide ), the risk of dying or developing any of these complications was reduced. It was also reduced in diabetic patients without atrial fibrillation who were given the same treatment.
Active treatment produced similar relative benefits to patients with and without atrial fibrillation. However, because of their higher risk at the start of the study, the absolute benefit associated with active treatment was greater in patients with atrial fibrillation than without.
Researchers estimate that five years of active treatment would prevent one death among every 42 patients with atrial fibrillation and one death among every 120 patients without this arrhythmia.
The findings have important implications for the management of diabetics and for policy in this area. Diabetes is a major global health problem, with an estimated worldwide prevalence of 2.8% in 2000, projected to increase to 4.4% in 2030. Atrial fibrillation is common in diabetic patients.
The prevalence of atrial fibrillation varies greatly according to the population's age and other health problems. It ranges between 4% in primary care settings to 15% in hospitalised patients.
In the ADVANCE study, 847 ( 7.6% ) of the 11,140 patients had atrial fibrillation at baseline and a further 352 patients developed atrial fibrillation over an average follow-up of 4.3 years. The overall prevalence in this population was about 11%. There are data to suggest that the prevalence of atrial fibrillation in people with diabetes is about twice that among people without diabetes.
The ADVANCE study informs clinicians that atrial fibrillation is a marker of greater risk of cardiovascular events and mortality among diabetics, both men and women. Such patients should have their cardiovascular risk factors, such as blood pressure and cholesterol, controlled more aggressively. This is a separate issue to rate and rhythm control ( or the use of anticoagulants to prevent thromboembolic events ), which is the usual therapeutic focus in patients with atrial fibrillation. These issues are important, but we believe our data suggest that heightened awareness and management of overall cardiovascular risk is also important.
An example of this comes from the results of the blood pressure intervention in ADVANCE. Routine administration of a fixed combination of Perindopril and Indapamide ( Coversyl Plus ) to patients with type 2 diabetes resulted in 18% reduction of cardiovascular death and 14% reduction of death from any cause in both patients with and without atrial fibrillation. However, because of their higher baseline risks, patients with atrial fibrillation benefited more, in absolute terms.
The study also found that there was a significantly stronger association between atrial fibrillation and deaths from cardiovascular disease in women compared with men. Women with atrial fibrillation were twice as likely to die than women without atrial fibrillation, whereas men with atrial fibrillation were 50% more likely to die then men without atrial fibrillation. As healthy women normally have a lower risk of death from heart disease than do men of a similar age, this increased risk in diabetic women with atrial fibrillation meant that the women's rates of death matched those of the men. ( Xagena )
Source: European Society of Cardiology, 2009