Shared genetic risk between anorexia nervosa and cardiovascular disease events: Evidence from genome‐wide association studies

OBJECTIVE: Cardiovascular complications occur in up to 80% of patients with anorexia nervosa (AN), yet the underlying mechanisms warrant further investigation. We assessed the genetic correlation (r_g ) between AN and cardiovascular disease (CVD) events to inform whether elevated cardiovascular risk among individuals with AN is due to shared genetic effects. METHOD: We used genome-wide association study summary statistics for AN (N = 72,517), AN with binge eating (N = 12,630), AN without binge eating (N = 12,516), and six CVD events (N = 390,142 to 977,323). We calculated the r_g s via linkage disequilibrium score regression and corrected for multiple testing using false discovery rate. RESULTS: Significant r_g s emerged between AN with heart failure (r_g  = -0.11, SE = 0.05, q = .04) and myocardial infarction (r_g  = -0.10, SE = 0.03, q = .01). AN with binge eating had a significant r_g with myocardial infarction (r_g  = -0.15, SE = 0.06, q = .02). No significant r_g emerged between AN without binge eating and any CVD event. DISCUSSION: Some loci affect the liability to AN and CVD in opposite directions and the shared genetic effects may not be consistent across all CVD events. Our results provide further evidence suggesting that the elevated cardiovascular risk in AN may not be due to shared genetic underpinnings, but more likely a downstream consequence of the disease.