Incidence and risk factors for atrial fibrillation in patients with newly diagnosed heart failure

Aims We aimed to identify the incidence and risk factors for first ever atrial fibrillation among patients with newly diagnosed heart failure following initial heart failure diagnosis. Methods A heart failure inception cohort of patients aged 20–89 years without atrial fibrillation or cancer (N = 14 457) from 2000 to 2005 was identified from The Health Improvement Network primary care database in the United Kingdom and followed for a mean of 2.67 years. First ever cases of atrial fibrillation were identified and controls (N = 3000) were frequency matched to cases by age and sex. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using unconditional logistic regression. Results One thousand four hundred and eighty-nine patients (10.3%) developed a first episode of atrial fibrillation: incidence rate 27.3/1000 person-years. A three-fold increased risk of atrial fibrillation was seen in the first 6 months after heart failure diagnosis, OR 3.62 (95% CI: 2.97–4.42) with the risk decreasing thereafter. Other risk factors were excessive alcohol consumption (OR 2.91, 1.60–5.30) and valvular heart disease (OR 1.98, 1.63–2.40) and use of oral steroids (OR 1.76, 95% CI: 1.40–2.22). Reduced risks of atrial fibrillation were found with use of statins (OR 0.65, 95% CI: 0.56–0.76) and β-blockers (OR 0.78, 95% CI: 0.67–0.91). Conclusions The incidence of first ever atrial fibrillation among newly diagnosed heart failure patients is high, especially in the first 6 months after diagnosis. This time relationship, together with the identified risk factors for atrial fibrillation, warrants consideration in the medical care of patients with heart failure.