Epigenetic Aging is Associated with Measures of Midlife Muscle Volume and Attenuation in CARDIA Study

Abstract

Abstract Background GrimAge acceleration (GAA), an epigenetic marker that represents physiologic aging, is associated with age-related diseases including cancer and cardiovascular diseases. However, the associations between GAA and muscle mass and function are unknown. Methods We estimated measures of GAA in 1118 Black and White participants from the Coronary Artery Risk Development in Young Adults (CARDIA) Study at exam years (Y) 15 (2000-01) and 20 (2005-06). Abdominal muscle composition was measured using CT scans at the year 25 (2010-11) visit. We used multivariate regression models to examine associations of GAA estimates with muscle imaging measurements. Results In the CARDIA study, each one-year higher GAA was associated with an average 1.1% (95% CI 0.6%, 1.5%) higher intermuscular adipose tissue [IMAT] volume for abdominal muscles. Each one-year higher GAA was associated with an average -0.089 Hounsfield unit (HU) (95% CI -0.146, -0.032) lower lean muscle attenuation and an average -0.049 HU (95% CI -0.092, -0.007) lower IMAT attenuation for abdominal muscles. Stratified analyses showed that GAA was more strongly associated with higher abdominal muscle IMAT volume in females and significantly associated with lower lean muscle attenuation for White participants only. Conclusions Higher GAA is associated with higher abdominal muscle IMAT volume and lower lean muscle attenuation in a midlife population.