Cardiovascular features of possible autonomous cortisol secretion in patients with adrenal incidentalomas

Low-grade incomplete post-dexamethasone cortisol suppression in patients with adrenal incidentalomas - recently defined as possible autonomous cortisol secretion (pACS) - has been associated with increased cardiovascular events and mortality. However, prospective studies documenting cardiac abnormalities in these patients are lacking.

Between July 2016 and September 2017, 71 consecutive patients with adrenal lesions were prospectively screened for hypercortisolism by dexamethasone suppression test (NCT 02611258). Complete anthropometric, metabolic and hormonal parameters were recorded along with full cardiac ultrasound assessment and noninvasive measurement of arterial stiffness. All patients underwent chemical-shift magnetic resonance imaging to characterize the lesions. Cardiovascular outcomes were recorded in blind.

According to post-dexamethasone suppression cortisol values (post-DST), 34 patients had pACS and 37 non-functioning adenomas (NFA). The two groups were similar in sex, BMI, age distribution, cardiovascular risk factors and comorbidities. Left ventricular mass index (LVMI^BSA) was increased in pACS compared to NFA (P = 0.006) and mildly correlated to the post-DST cortisol level (rho = 0.347; P = 0.004). The post-DST cortisol levels explained up to 13.7% of LVMI^BSA variance (P = 0.002). Compared to NFA, patients with pACS had a higher prevalence of diastolic dysfunction (35.1% vs 82.6%; P = 0.001) and worse arterial stiffness assessed by pulse wave velocity (P = 0.033).

In apparently asymptomatic patients, mild autonomous cortisol secretion can sustain early cardiac and vascular remodeling, independently of other risk factors. The morphological and functional cardiovascular changes observed in pACS underline the need for further studies to correctly define the long-term management of this relatively common condition.