IMPACT-MACS Study: Investigating the Mechanisms, Pathophysiology, and Cardiometabolic Treatment in Mild Autonomous Cortisol Secretion
University of Texas Southwestern Medical Center
Summary
The goal of this study is to learn how two treatments-adrenalectomy (surgical removal of an adrenal gland) and semaglutide (a medication used for weight management)-affect insulin resistance and cortisol regulation in adults with mild autonomous cortisol secretion (MACS). The study will also learn how these treatments impact body composition, blood pressure, cholesterol, inflammation, muscle strength, and quality of life. The main questions the study aims to answer are: 1. Does adrenalectomy or semaglutide improve insulin resistance more in people with MACS? 2. How do these treatments change cortisol patterns and other cardiometabolic risk factors? 3. Do people with MACS respond differently to semaglutide compared to matched adults without MACS? Participants will: 1. Receive either adrenalectomy or semaglutide if they have MACS, or semaglutide if they are matched controls 2. Complete clinic visits and phone visits over about 26-30 weeks 3. Undergo metabolic testing such as blood tests, urine steroid profiling, body composition scans, blood pressure monitoring, muscle strength testing, and questionnaires about health and well-being
Description
This single-center, prospective, interventional study evaluates metabolic responses to surgical versus medical treatment in adults with mild autonomous cortisol secretion (MACS). The study includes: 1. a randomized controlled trial comparing adrenalectomy to semaglutide in MACS, and 2. a parallel matched case-control comparison evaluating semaglutide effects in MACS versus matched controls without adrenal tumors. The primary objective is to compare changes in insulin sensitivity measured by hyperinsulinemic-euglycemic clamp (M-value) from baseline to week 26. Secondary outcomes include corti…
Eligibility
- Age range
- 18+ years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Adults ≥18 years * MACS groups: adrenal adenoma + DST cortisol \>1.8 µg/dL + no overt Cushing + eligible for adrenalectomy * Willingness to postpone surgery 6 months if randomized * Controls: no adrenal abnormalities + normal DST + BMI ≥27 + ≥2 cardiometabolic conditions * Stable medication doses for ≥4 weeks * Negative pregnancy test if applicable Exclusion Criteria: * Prior GLP-1 RA within 90 days * Weight change \>5 kg in past 90 days * Prior obesity/diabetes surgery * Type 1 diabetes or other diabetes types * Severe organ disease * Recent pancreatitis * Pregnancy,…
Interventions
- ProcedureIntervention 1: Adrenalectomy
Surgical removal of one adrenal gland performed by an endocrine surgeon following institutional standard-of-care practices. Includes postoperative monitoring for adrenal insufficiency and routine clinical follow-up.
- DrugIntervention 2: Semaglutide
Once-weekly subcutaneous semaglutide administered according to FDA-approved titration for chronic weight management (0.25 mg to 2.4 mg weekly as tolerated). Participants receive training on injection technique, dose escalation, and safety monitoring.
Location
- University of Texas Southwestern Medical CenterDallas, Texas