Endocrine Abstracts

Introduction: Primary aldosteronism (PA) is associated with increased prevalence of metabolic disorders such as impaired glucose and lipid metabolism and insulin resistance. Individuals with PA have an increased risk of cardiovascular events. The aim of this study is to determine the characteristics of metabolic syndrome (MS) in patients with PA.

Patients and methods: Retrospective study concerning 40 patients with PA over the period of 10 years from January 2010 to December 2022. The MS was diagnosed according to the worldwide definition of the International Diabetes Federation (IDF).

Findings: The average age of our patients was 55.4 years. There were 16 men and 24 women. Hypertension was present in 39 patients. Severe hypertension was found in 11 cases and resistant hypertension in 4 others. The average Body Mass Index (BMI) was 29.7 kg/m². Obesity was documented in 42.5%. It was classified as grade I in the majority of instances. The android distribution was present in 90% of cases. The mean waist circumference (WC) was 102 cm. In terms of lipid profile, dyslipidemia was diagnosed in 30 of our patients, with 7 patients already undergoing treatment. Mixed dyslipidemia was the most common type (35%), followed by isolated low HDL-cholesterol (10%). Among our 40 patients, 16 had diabetes. The exploration of glucose homeostasis diagnosed 9 new cases of impaired glucose tolerance. Metabolic syndrome was present in 82.5% of cases. Among them, 13 patients met all the diagnostic criteria according to the IDF. An analytical study of MS in PA revealed that among anthropometric parameters, only WC was significantly higher in patients with MS (P=0.005). Biochemically, triglycerides levels were higher in patients with MS (1.7 vs 0.9 mmol/l; P=0.002), while HDL-cholesterol levels were higher in patients without MS (1.1 vs 1.4 mmol/l; P=0.024). Bilateral adrenal hyperplasia was the most frequent aetiology of PA among the patients presenting with MS.

Conclusion: Recent studies have shown that MS is more common in hypertensive individuals with PA than in those with essential hypertension. These findings suggest the possibility of aldosterone effects on carbohydrate metabolism through insulin secretion and/or insulin resistance. Indeed, hypokalemia is a factor contributing to decreased insulin production. Additionally, chronic potassium depletion observed in PA is responsible for insulin resistance that persists even after correction of hypokalemia. This implies a direct action of aldosterone on insulin receptors, associated with development of MS.