Impact of hypercortisolism on skeletal muscle mass and adipose tissue mass in patients with adrenal adenomas.

Abstract

Abdominal visceral adiposity and central sarcopenia are markers of increased cardiovascular risk and mortality. To assess whether central sarcopenia and adiposity can serve as a marker of disease severity in patients with adrenal adenomas and glucocorticoid secretory autonomy. Retrospective cohort study. Twenty-five patients with overt Cushing's syndrome (CS), 48 patients with mild autonomous cortisol excess (MACE) and 32 patients with a nonfunctioning adrenal tumour (NFAT) were included. Medical records were reviewed, and body composition measurements (visceral fat [VAT], subcutaneous fat [SAT], visceral/total fat [V/T], visceral/subcutaneous [V/S] and total abdominal muscle mass) were calculated based on abdominal computed tomography (CT). In patients with overt CS, when compared to patients with NFAT, the V/T fat and the V/S ratio were increased by 0.08 (P<.001) and by 0.3 (P<.001); however, these measurements were decreased by 0.04 (P=.007) and 0.2 (P=.01), respectively, in patients with MACE. Total muscle mass was decreased by -10cm2 (P=.02) in patients with overt CS compared to patients with NFAT. Correlation with morning serum cortisol concentrations after dexamethasone suppression testing revealed that for every 28nmol/L cortisol increase there was a 0.008 increase in V/T (P<.001), 0.02 increase in the V/S fat ratio (P<.001) and a 1.2cm2 decrease in mean total muscle mass (P=.002). The severity of hypercortisolism was correlated with lower muscle mass and higher visceral adiposity. These CT-based markers may allow for a more reliable and objective assessment of glucocorticoid-related disease severity in patients with adrenal adenomas.