SUN-144 High Prevalence of Diabetes in Patients with Primary Aldosteronism (PA) Associated with Subclinical Hypercortisolism and Prediabetes More Prevalent in Bilateral Than Unilateral PA

INTRODUCTION: Primary aldosteronism (PA) is characterized by the autonomous production of aldosterone, usually from an aldosterone producing adenoma in one adrenal gland or idiopathic hyperaldosteronism, with bilateral adrenal lesions. It has been suggested that aldosterone overproduction, hypokalemia, or the complication of subclinical hypercortisolism (SH) in patients with PA, are related to impaired glucose homeostasis and insulin resistance. However, the true contributions of these factors to disturbances of carbohydrate metabolism in PA have not been investigated thoroughly from a large-scale epidemiologic viewpoint. In the present study, the true prevalence of glucose intolerance in more than 2000 patients with PA and its association with aldosterone concentration, hypokalemia, and SH were studied in a multicenter collaborative study. METHODS: The prevalence of diabetes was determined in 2210 patients with PA (diagnosed or HbA(1c) ≥6.5%, NGSP) and compared with that of the Japanese general population from the National Survey of the Ministry of Health, Labour and Welfare in 2016, according to age and sex. In 1386 patients with PA and clear laterality (unilateral or bilateral), the effects of plasma aldosterone concentration (PAC), hypokalemia (<3.5 mEq/L), suspected SH (serum cortisol ≥1.8 μg/dL after 1-mg dexamethasone suppression test) and PA laterality on the prevalence of diabetes or prediabetes (5.7%≤HbA(1c)<6.5%) were examined. RESULTS: Of the 2210 patients with PA, 477 (21.6%) had diabetes, this prevalence of being higher than that of the general population (12.1%) or in 10 year cohorts aged 30 to 69 years. According to the χ(2) test, diabetes was present significantly more frequently in PA patients with suspected SH (26.8%) than in those with F-1mgDST <1.8 μg/dL (16.9%; p=0.001). When using logistic regression analysis, it was found that age, sex, BMI, and F-1mgDST ≥1.8 μg/dL were significant contributing factors to the presence of diabetes, whereas laterality of PA was not a significant factor. Despite more active PA profiles (e.g. higher PAC, lower potassium concentrations) in unilateral than bilateral PA, BMI and HbA(1c) values were significantly higher in bilateral PA. PA laterality had no effect on prevalence of diabetes; however, prevalence of prediabetes was significantly higher in bilateral than unilateral PA. CONCLUSIONS: Individuals with PA have a high prevalence of diabetes, which is associated mainly with SH. The prevalence of prediabetes is greater for bilateral than unilateral PA, suggesting a unique metabolic cause of bilateral PA. SUPPORT: This research was supported by the Japan Agency for Medical Research and Development (AMED) for the Practical Research Project for Rare/Intractable Disease.