Co-existing primary aldosteronism (PA) and autonomous cortisol secretion (ACS) has been recently recognized as a distinct entity. This study aimed to assess the incidence of ACS in patients with PA, and its impact on clinical and laboratory parameters.

Ninety-two patients diagnosed with PA were included. Demographic data, comorbidities, laboratory and imaging results were retrospectively analyzed. Patients with overnight 1mg dexamethasone suppression test>1.8μg/dL were classified as PA with ACS.

Twenty-four patients (26.1%) were in the PA-with-ACS group, and 68 (73.9%) in the PA-without-ACS group. Mean age (P=0.034), body mass index (P=0.034), number of female patients (P=0.012) and maximum adenoma diameter (P<0.001) were higher in the PA-with-ACS group than in the PA-without-ACS group. Basal (P=0.001) and post-saline infusion plasma aldosterone concentrations (PAC) (P=0.009) were higher in the PA-without-ACS group than in the PA-with-ACS group. No significant differences between groups were found in intensity of antihypertensive treatment, presence of type 2 diabetes, coronary artery disease, proteinuria or glomerular filtration rate (P>0.05). Left ventricular hypertrophy (LVH) was detected in 49.4% of patients. Logistic regression demonstrated that PAC and gender were associated factors for LVH.

Cortisol co-secretion was identified in approximately one-quarter of patients diagnosed with PA. PA patients without ACS had higher PAC than those with co-existing ACS. According to our results, the co-existing ACS may not seem to have a significant negative impact on clinical parameters in patients with PA.