Subclinical atherosclerosis is associated with incident atrial fibrillation: a systematic review and meta-analysis

Aims Coronary artery disease is an established risk factor for incident atrial fibrillation (AF), but it is unclear whether subclinical atherosclerosis also increases the risk of incident AF. Therefore, the aim was to assess the association between subclinical atherosclerosis, defined by increased carotid intima-media thickness (cIMT) or coronary artery calcium score (CACS), and incident AF. Methods and results A systematic review of MEDLINE, EMBASE, and Cochrane was done to find all cohort studies investigating the association between subclinical atherosclerosis, defined by increased cIMT or CACS, and incident AF. Eligible articles had to be available in an English full-text version; include adults over the age of 18 years; include ≥100 participants; and have a follow-up period ≥12 months. Data on cIMT were pooled using a fixed-effects model, while data on CACS (I2 >25) were pooled using a random-effects model. Five studies on cIMT including 36 333 patients and two studies on CACS including 34 603 patients were identified. All studies investigating the association between increased cIMT and incident AF showed a significant association, with an overall hazard ratio (HR) of 1.43 [95% confidence interval (CI) 1.27–1.59]. The two studies investigating the association between increased CACS and AF also showed a significant association with an overall HR of 1.07 (95% CI 1.02–1.12). Conclusion Data from seven observational studies suggest that subclinical atherosclerosis defined by increased cIMT or CACS is associated with an increased risk of incident AF. These findings emphasize the need for further research investigating whether treatment of subclinical atherosclerosis should be a part of the initiatives to prevent AF.