Nonfunctioning adrenal incidentalomas with cortisol post-dexamethasone suppression test >0.9 µg/dL have a higher prevalence of cardiovascular disease than those with values ≤0.9 µg/dL.

Purpose: To analyze the differences in the cardiometabolic profile in patients with nonfunctioning adrenal incidentalomas (NFAI) with post-dexamethasone suppression test (DST) cortisol ≤1.4 µg/dL (NFAI ≤ 1.4) and those with post-DST cortisol >1.4 µg/dL (NFAI > 1.4) and between NFAI with post-DST cortisol ≤0.9 µg/dL (NFAI ≤ 0.9) and those with levels >0.9 µg/dL (NFAI > 0.9).

Methods: Multicenter retrospective observational study of patients with NFAIs. NFAI was defined as an adrenal incidentaloma with negative hormonal study (including metanephrines, post-DST cortisol ≤1.8 µg/dL and aldosterone/renin ratio when screening was indicated). Autonomous cortisol secretion (ACS) development was defined as an NFAIs in which post-DST serum cortisol >1.8 µg/dL were evidenced during hormonal follow-up evaluation.

Results: A total of 593 NFAI were included. Based on the 1.4 µg/dL threshold in the DST, most of the NFAI were classified as NFAI ≤ 1.4 (74.5%). Patients in the NFAI > 1.4 group were older than those in the NFAI ≤ 1.4 group, but there was no difference in the cardiometabolic profile after adjusting for age. A total of 69.5% of the patients had DST > 0.9 µg/dl. They were older and had a higher prevalence of cardiovascular disease than NFAI ≤ 0.9, even after adjusting by age (adjusted OR = 2.23 [1.10-4.53]). Patients in the NFAI > 1.4 group developed ACS more commonly than the NFAI ≤ 1.4 group (23.5% vs. 7.44%, P < 0.001). However, when the threshold of 0.9 µg/dL was considered, no difference was found between NFAI ≤ 0.9 and NFAI > 0.9 (P = 0.126).

Conclusion: The threshold of 1.4 µg/dL in the DST is useful to predict which patients with NFAI had a higher risk of ACS development during follow-up; and the threshold of 0.9 µg/dL to identify those patients with NFAI with a higher cardiovascular risk.