Is the 1mg-dexamethasone suppression test a precise marker of glucocorticoid excess and cardiometabolic risk in patients with adrenal incidentalomas?

The Influence of Remnant Cholesterol on Cardiovascular Risk and Mortality in Patients with Non-Functional Adrenal Incidentalomas and Mild Autonomous Cortisol Secretion: A Retrospective Cohort Study

Background: Increased cardiovascular risk has been described in individuals with adrenal incidentalomas. The aim of the present study is to assess the effect of remnant cholesterol (RC) on the cardiovascular risk and mortality of patients with adrenal incidentalomas. Methods: A retrospective cohort study was conducted with patients with adrenal incidentalomas between 2001 and 2024. One hundred thirty-seven patients (mean age of 61.2 ± 11.5 years; 56.6% women) with non-functioning adrenal incidentalomas and with mild autonomous cortisol secretion (MACS) (cortisol post-dexamethasone suppression test ≥1.8 µg/mL) were included. The patients were divided into two groups using 30 mg/dL as the cut-off for RC. Logistic regression models were used to study the impact of RC on major adverse cardiovascular events and mortality (MACEs). Results: Patients with RC ≥ 30 mg/dL exhibited a higher prevalence of type 2 diabetes mellitus (T2D) (p < 0.001), lower HDL-C (p < 0.001) and LDL-C (p = 0.025) levels, a higher frequency of treatment with statins (p = 0.032), and a higher rate of non-fatal major cardiovascular events (p = 0.038) and MACEs (p = 0.038). Patients with MACS showed no differences in RC or complications during the follow-up. The relative risk of high RC was 2.65 (1.04-6.77) for cardiovascular events and 2.27 (1.05-4.92) for MACEs, with p < 0.05 in both cases. The only variables independently affecting MACEs were age ([odds ratio] OR = 1.13 [p = 0.004]), female sex (OR = 0.20; p = 0.016), LDL-C (OR = 1.02; p = 0.029), and RC (OR = 1.06; p = 0.014). T2D and HDL-C were not independently associated with MACEs. Conclusions: RC ≥30 mg/dL in patients with adrenal incidentalomas was associated with a higher prevalence of T2D, lower HDL-C levels, and a higher risk of MACEs. MACS was not associated with RC or MACEs during the follow-up.

Mild autonomous cortisol secretion: pathophysiology, comorbidities and management approaches

The majority of incidentally discovered adrenal tumours are benign adrenocortical adenomas and the prevalence of adrenocortical adenomas is around 1-7% on cross-sectional abdominal imaging. These can be non-functioning adrenal tumours or they can be associated with autonomous cortisol secretion on a spectrum that ranges from rare clinically overt adrenal Cushing syndrome to the much more prevalent mild autonomous cortisol secretion (MACS) without signs of Cushing syndrome. MACS is diagnosed (based on an abnormal overnight dexamethasone suppression test) in 20-50% of patients with adrenal adenomas. MACS is associated with cardiovascular morbidity, frailty, fragility fractures, decreased quality of life and increased mortality. Management of MACS should be individualized based on patient characteristics and includes adrenalectomy or conservative follow-up with treatment of associated comorbidities. Identifying patients with MACS who are most likely to benefit from adrenalectomy is challenging, as adrenalectomy results in improvement of cardiovascular morbidity in some, but not all, patients with MACS. Of note, diagnosis and management of patients with bilateral MACS is especially challenging. Current gaps in MACS clinical practice include a lack of specific biomarkers diagnostic of MACS-related health outcomes and a paucity of clinical trials demonstrating the efficacy of adrenalectomy on comorbidities associated with MACS. In addition, little evidence exists to demonstrate the efficacy and safety of long-term medical therapy in patients with MACS.

Epidemiology and Management of Hypertension and Diabetes Mellitus in Patients with Mild Autonomous Cortisol Secretion: A Review

Mild autonomous cortisol secretion (MACS) is associated with a higher cardiometabolic risk than that observed in patients with nonfunctioning adrenal adenomas and in the general population. In patients with MACS, the excess of glucocorticoids affects various metabolic pathways, leading to different manifestations of metabolic syndrome and other comorbidities. Hypertension and diabetes mellitus are two of the most common cardiometabolic comorbidities associated with MACS, reaching a prevalence of up to 80% and up to 40%, respectively. In addition, they are the comorbidities that experienced a greater improvement after adrenalectomy in patients with MACS. Hypertension pathogenesis is multifactorial, including the coexistence of comorbidities such as obesity or diabetes and the role of the different polymorphisms of the glucocorticoid receptor gene, among others. Glucocorticoid-induced diabetes mellitus is mainly related to the detrimental effects of glucocorticoids on insulin-dependent glucose uptake in peripheral tissues, gluconeogenesis and insulin secretion. There are no specific recommendations for hypertension and diabetes treatment in patients with MACS. Thus, considering the similar underlying pathogenesis of hypertension and diabetes mellitus in overt and mild hypercortisolism, our recommendation is to follow this general stepwise approach: surgically remove the adrenal culprit lesion to induce remission from hypercortisolism; control hypercortisolism with steroidogenesis inhibitors; and treat elevated blood pressure or high glucose levels using carefully selected anti-hypertensives and glucose-lowering medications if blood pressure and glucose levels remain uncontrolled, respectively. In this review, we summarize the epidemiology, physiopathology and management of diabetes mellitus and hypertension in patients with MACS.