Adrenal adenomata displaying mild autonomous cortisol secretion: a service evaluation of cardiometabolic profile...

A proportion of adrenal adenomata exhibit autonomous cortisol secretion, now termed mild autonomous cortisol secretion (MACS), as defined by post-1mg overnight dexamethasone suppression test (ONDST) cortisol 51-137 nmol/l. Here, we characterized the cardiometabolic profile of MACS.

Clinical records of 98 individuals with adrenal adenomata were examined. Subcategorization into MACS1 (ONDST cortisol of 50-137 nmol/l) and MACS2 (ONDST cortisol of >137 nmol/l was created to take account of individuals with ONDST cortisol of more than 137 nmol/l and no diagnosis of Cushing's syndrome.

Diagnosis of MACS1 associated with a higher diagnosis rate of cardiovascular disease (CVD) (17.7% MACS1) vs. non-MACS = nonfunctioning adenoma (NFA) (3.7%) (P = 0.009) and higher rates of prescription of lipid-lowering agents (51.6%) vs. (29.6%) (P = 0.01). ONDST cortisol levels in MACS1 patients correlated with a more adverse lipid profile (for higher low-density lipoprotein cholesterol, r ² = 0.404, P = 0.007; high-density lipoprotein cholesterol r ² = -0.346, P = 0.023; for higher serum triglycerides r ² = 0.282, P = 0.02) in spite of higher rates of statin prescribing. There was a gradient of increasing numbers of antihypertensives prescribed, going from non-MACS NFA to MACS1 to MACS2. Dunn's post hoc analysis indicated an overall more adverse lipid profile in MACS1.

The positive direction of associations between serum cortisol and lipid measures highlights that MACS carries a metabolically adverse lipid profile. Diagnosis of MACS was associated with a higher diagnosis rate of CVD and appropriately higher rates of prescription of lipid-lowering agents and a greater number of antihypertensive agents prescribed. The question remains about whether a specific directed treatment of MACS should be offered beyond risk-factor-mitigating management.