Metabolic profile differences in ACTH-dependent and ACTH-independent Cushing syndrome

The most common etiologies of Cushing's syndrome (CS) are adrenocorticotropic hormone (ACTH)-producing pituitary adenoma (pitCS) and primary adrenal gland disease (adrCS), both of which burden patients with metabolic disturbance. The aim of this study was to compare the metabolic features of pitCS and adrCS patients.

A retrospective review including 114 patients (64 adrCS and 50 pitCS) diagnosed with CS in 2009-2019 was performed. Metabolic factors were then compared between pitCS and adrCS groups.

Regarding sex, females suffered both adrCs (92.2%) and pitCS (88.0%) more frequently than males. Regarding age, patients with pitCS were diagnosed at a younger age (35.40 ± 11.94 vs. 39.65 ± 11.37 years, p = 0.056) than those with adrCS, although the difference was not statistically significant. Moreover, pitCS patients had much higher ACTH levels and more serious occurrences of hypercortisolemia at all time points (8 AM, 4 PM, 12 AM) than that in adrCS patients. Conversely, indexes, including body weight, BMI, blood pressure, serum total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglycerides, fasting plasma glucose, and uric acid, showed no differences between adrCS and pitCS patients. Furthermore, diabetes prevalence was higher in pitCS patients than in adrCS patients; however, there were no significant differences in hypertension or dyslipidemia prevalence between the two.

Although adrCS and pitCS had different pathogenetic mechanisms, different severities of hypercortisolemia, and different diabetes prevalences, both etiologies had similar metabolic characteristics.