A Lifestyle Risk Score for Prediction of Incident AF: Development and Validation of the HARMS ≪sub>2</sub>-Af Score

Background: Lifestyle risk factors (RFs) are a modifiable target in atrial fibrillation (AF) management. The relative contribution of individual lifestyle RFs to the development of AF has not been described.Objective: Development and validation of an AF-lifestyle risk score to identify individuals at risk of AF in the general population.Methods: The UK Biobank and Framingham Heart Study are large prospective cohorts with outcomes measured >10 years. Incident AF was based on ICD-10 coding. Prior AF was excluded. Regression analysis identified independent predictors of AF, which were evaluated in a multivariable model. A weighted score was developed in the UK Biobank population and externally validated in the Framingham Heart Study (FHS). Kaplan-Meier estimates ascertained the 10-year risk of AF.Findings: In the UKB, AF incidence was 5·3% among 302,926 participants, with median time to AF 7·3 years (IQR 4·3-9·8). Hypertension, Age, Raised BMI (obesity, BMI >30kg/m2), Male sex, Sleep apnoea, Smoking and Alcohol were predictive variables (all p<0·001); physical inactivity (OR 1·02,95%CI 0·97-1·10, p=0·547), diabetes (OR 0·98, 95% CI 0·91-1·06, p=0·626) and BMI 27-30kg/m2 (OR 1·02, 95%CI 0·97-1·07, p=0·424) were not significant. The HARMS2-AF score had similar predictive performance (AUC=0·782) to the unweighted regression model (AUC 0·808) in UKB. Validation in the FHS (AF incidence 6·7% of 7206 participants) demonstrated an AUC of 0·747 (95% CI 0·724-0·769). Higher HARMS2-AF score ( > 5 points) was associated with heightened 10-year AF risk (score 5-9: OR 9·35, score 10-14: OR 33·34).Interpretation: The HARMS 2 -AF score is a novel lifestyle risk score which may help identify individuals at risk of AF and assist in general population screening.Funding: None.Declaration of Interest: The following industry funding sources regarding activities outside the submitted work have been declared in accordance with ICMJE guidelines. Dr Segan is supported by NHMRC / NHF post-graduate scholarship. Prof. Peter M Kistler has received funding from Abbott Medical for consultancy and speaking engagements and fellowship support from Biosense Webster. Prof. Jonathan Kalman has research and fellowship support from Medtronic and Biosense Webster. All other authors declare no competing interests.Ethical Approval: . The UK Biobank was granted ethical approval from the UK Biobank ResearchEthical Committee (reference # 11/NW/0382)