Alcohol-related hospitalization is associated with increased risk of ischaemic stroke among low-risk patients with atrial fibrillation.

Aims: Patients with atrial fibrillation (AF) under the age of 65 and CHA2DS2-VASc risk score of 0 in men or 1 in women are considered to be at low risk for ischaemic stroke, and therefore without benefit of oral anticoagulation therapy. The objective of this study is to assess the incidence and predictors of ischaemic stroke among low-risk patients with AF identified from a National Patient Register.

Methods and results: A retrospective study of 25 252 low-risk AF patients (age 18-64) out of total 345 123 AF patients identified from the Swedish Nationwide Patient Register for the period 1 January 2006 to 31 December 2012. During a median follow-up of 5.0 (interquartile range 2.9-6.8) years, ischaemic stroke occurred at an annual rate of 0.34 per 100 patient-years [95% confidence interval (CI) 0.31-0.38]. Significant predictors of stroke were age, hazard ratio (HR) 1.06 (CI 1.05-1.08) per incremental year, and previous alcohol-related hospitalization HR 2.01 (CI 1.45-2.79). Intracerebral bleeding events were rare and not statistically different HR 2.05 (CI 0.76-5.56) between patients with and without alcohol-related hospitalizations. Use of oral anticoagulants was associated with lower risk for ischaemic stroke, HR 0.78 (CI 0.63-0.97).

Conclusion: The presence of a previous hospitalization with an alcohol-related disease was associated with a small but significant increase in the risk of stroke among low-risk AF patients. More research about relation between alcohol use and ischaemic stroke in AF patients is warranted.