Resting Metabolic Rate in Adults with Facioscapulohumeral Muscular Dystrophy (FSHD).

Determine whether resting metabolic rate (RMR) is altered in adults with facioscapulohumeral muscular dystrophy (FSHD). Eleven people with FSHD (51±12yrs, 2 females) and eleven controls (48±14yrs, 2 females) completed one visit, including 30-minutes of indirect calorimetry and dual-energy x-ray absorptiometry (DXA) scanning. RMR was calculated from resting oxygen consumption/carbon dioxide production; regional/whole-body fat mass and lean mass were collected from the DXA scan. Absolute RMR was 15% lower in FSHD (p=0.04); when normalized to regional/local lean mass, no differences in RMR were observed (p>0.05). Absolute RMR was correlated with total lean mass for all participants combined (p 0.05 for both). When RMR was expressed relative to lean body mass, no differences in RMR were found, indicating that the lower levels of lean mass observed in FSHD patients likely contribute to the lower absolute RMR values. Novelty bullets: • Resting metabolic rate (RMR) is lower among people with FSHD, as compared with controls • The reduced RMR among people with FSHD is due to disease-related loss in muscle mass and likely related to lower physical activity and/or exercise levels.