HMW adiponectin levels in mild autonomous cortisol secretion and non-functioning adrenal adenoma: Impact of cortisol autonomy.

OBJECTIVE: To compare cardiometabolic features and serum high molecular weight (HMW) adiponectin levels between patients with mild autonomous cortisol secretion (MACS) and non-functioning adrenal adenoma (NFAA), and to explore the associations of HMW adiponectin with low-grade cortisol autonomy and cardiometabolic parameters. METHODS: Seventy-two patients with adrenal adenomas (48 MACS and 24 NFAA; 2:1 ratio) matched for age, sex, and body mass index (BMI) were included. Serum HMW adiponectin concentrations were measured using ELISA. Metabolic syndrome (MetS) was defined according to the NCEP-ATP III criteria, and the cardiometabolic index (CMI) was calculated. RESULTS: Dyslipidemia prevalence and HbA1c levels were significantly higher in patients with MACS than in those with NFAA (p < 0.05). MetS prevalence was 50.0% in MACS and 37.5% in NFAA (p = 0.316). The CMI did not differ significantly between the groups (p > 0.05). Serum HMW adiponectin levels were significantly higher in patients with MACS compared with NFAA (2143.8 ± 940.2 vs 1386.0 ± 649.5 ng/mL, p < 0.001). In the overall cohort, HMW adiponectin correlated positively with post-dexamethasone suppression test (DST) cortisol and negatively with ACTH, waist circumference, and waist-to-height ratio (p < 0.05). In multivariable analysis, post-DST cortisol and waist circumference were associated with HMW adiponectin levels. CONCLUSION: HMW adiponectin levels were higher in MACS compared with NFAA and positively associated with post-DST cortisol levels, despite higher dyslipidemia prevalence and HbA1c levels. These findings suggest that mild cortisol autonomy may be associated with altered HMW adiponectin regulation. However, the higher HMW adiponectin levels observed in MACS should not be interpreted as a metabolically protective response.