Low cardiac vagal control is associated with genetic liability for elevated triglycerides and risky health behaviors.

Low parasympathetic regulation of cardiac activity, known as cardiac vagal control (CVC), is robustly associated with poor health outcomes. However, the etiological mechanism that undergirds this association remains largely unknown. One explanation is a causal relationship wherein health problems cause low CVC, or vice versa. However, an alternative explanation is that a common set of genetic factors contributes to both increased liability for poor health and low CVC (i.e., pleiotropy). The present study uses polygenic risk scores for a number of health-related phenotypes (physical, mental, behavioral) to test whether genetic liability for poor health has pleiotropic effects on CVC. We report evidence for shared genetic liability between low CVC and both poor physical health (elevated triglycerides) and risky health-related behaviors (increased drinking and sexual activity). The present findings are consistent with shared genetic liability explaining, at least in part, the well-documented correlation between CVC and health.