Atrial fibrillation patients more likely to develop cancer

The risk of cancer is higher among patients with atrial fibrillation (AF), a recent study has found. Among important risk factors are comorbidities such as diabetes, hypertension and liver cirrhosis.

The study included 332,555 AF patients (mean age, 70.8±13.1 years; 55.2 percent male) with no history of cancer, enrolled from Taiwan’s National Health Insurance Research Database. Cancer incidence data in the general population were retrieved from the National Cancer Registry. Majority of the participants had hypertension.

Over a median follow-up of 3.1 years, 22,911 incident cases of cancer were observed, leading to an incidence rate of 1.65 percent per year. This was higher in males than in females (1.92 vs 1.31 percent per year).

The peak of cancer incidence occurred a year after AF diagnosis, with 7,413 such cases. The corresponding rate was 2.65 percent per year. This was significantly higher than rates of cancer incidence ≥10 years after AF incidence (incidence risk ratio, 10.20, 95 percent CI, 9.57–10.89).

AF patients likewise suffered from a significantly elevated risk of cancer relative to general population controls (standardized incidence ratio [SIR], 1.37, 1.36–1.39). This remained true even after disaggregation according to sex: males (SIR, 1.37, 1.35–1.40) and females (SIR, 1.37, 1.34–1.40). This relationship also remained significant across all age categories.

Multivariable Cox regression analysis found that significant predictors of cancer among AF patients were age ≥65 years, male sex, hypertension, diabetes, chronic obstructive pulmonary disease and liver cirrhosis. The incidence of cancer in patients with all six risk factors was 2.76 percent per year, as compared to only 0.70 percent per year in AF patients without any risk factor.