sST2 levels are associated with all‐cause mortality in anticoagulated patients with atrial fibrillation

Background Atrial fibrillation ( AF ) is associated with high morbidity and mortality, even despite the use of oral anticoagulation ( OAC ). Soluble suppression of tumorigenicity‐2 ( sST 2) is a member of the interleukin‐1 receptor family [interleukin‐1 receptor‐like 1 ( IL 1 RL 1)], which has been associated with an increased risk of mortality and morbidity in heart failure or acute coronary syndrome. We assessed the predictive value of sST 2 levels in an unselected ‘real‐world’ cohort of anticoagulated AF patients. Methods We included 562 patients (49% male; median age 77 [ IQR : 71–82]) with permanent AF who were stable (for at least 6 months) on OAC ( INR s 2·0–3·0). sST 2 levels were quantified by ELISA . Patients were followed‐up for up to 4 years, and cardiovascular events and all‐cause mortality were recorded. Results Median ( IQR ) of sST 2 levels was 51·23 (39·09–67·40) μg/L. Median follow‐up was 1587 days [ IQR 1482–1617], and during this period, 91 patients died (16·2%, 3·72%/year). The c‐statistic for predicting mortality with sST 2 was 0·58 + 0·03; P  = 0·017). On multivariate analysis, age [hazard ratio ( HR ) 1·09 (1·05–1·13); P  < 0·001], diabetes mellitus [1·76 (1·08–2·88); P  = 0·023], previous stroke [2·16 (1·29–3·60); P  = 0·003] and sST 2 levels [1·008 (1·002–1·14); P  = 0·008] were independently associated with mortality. Concentrations of sST 2 were also significantly associated with the risk of mortality, even after adjusting for the CHA 2 DS 2 – VAS c score [ HR : 1·007 (1·001–1·013); P  = 0·014]. Conclusions In an anticoagulated AF patient's cohort, sST 2 levels are an independent predictive factor of all‐cause mortality. sST 2 levels could be a biomarker used to improve clinical risk assessment in anticoagulated AF patients.