The endocrine manifestations of adults with spinal muscular atrophy

• Published in: Muscle & nerve 2024-12, Vol.70 (6), p.1230-1239
• Main Authors: Rakusa, Matej, Koritnik, Blaž, Leonardis, Lea, Goricar, Katja, Rudolf, Tjasa, Firbas, Dejan, Snoj, Žiga, Jensterle, Mojca
• Format: Article
• Language: English
• Subjects: Abnormalities; Adult; Adults; Atrophy; beta‐hydroxybutyrate; Blood; Blood Glucose - metabolism; Body Composition; Body fat; Body mass index; Body size; Cross-Sectional Studies; Dyslipidemia; Endocrine System Diseases - blood; Endocrine System Diseases - etiology; Female; Glucose; glucose metabolism; Glucose tolerance; Glucose Tolerance Test; Glycated Hemoglobin - metabolism; Growth factors; Health risks; Hemoglobin; Humans; Hydrocortisone - blood; Hyperglycemia; Hypogonadism; Insulin; Insulin - blood; Insulin resistance; Insulin Resistance - physiology; Insulin-Like Growth Factor I - metabolism; Insulin-like growth factors; lipid profile; Lipids; Male; Metabolism; Middle Aged; Muscular Atrophy, Spinal - blood; Muscular Atrophy, Spinal - complications; Muscular Atrophy, Spinal - physiopathology; Spinal muscular atrophy; Testosterone; Testosterone - blood
• ISSN: 0148-639X; 1097-4598; 1097-4598
• DOI: 10.1002/mus.28275

Introduction/Aims Changes in body composition in patients with spinal muscular atrophy (SMA) can cause endocrine abnormalities that are insufficiently studied in adults. We aimed to assess the endocrine profile in a cohort of adults with SMA. Second, we compared body composition and endocrine profiles between nonambulatory and ambulatory patients and between different types of SMA. Methods The cross‐sectional study included 29 SMA patients (18 [62.1%] males and 11 [37.9%] females) of median age 44 (IQR 30–51.5) years with type 2, 3, or 4. Body composition was measured by bioimpedance. Morning blood samples were drawn for glycated hemoglobin (HbA1c), lipid profile, testosterone, cortisol, and insulin‐like growth factor‐1 (IGF‐1). Blood glucose, insulin, and beta‐hydroxybutyrate (BHB) were measured during a 75 g oral glucose tolerance test. The homeostatic model assessment for insulin resistance index was calculated. Results In total, 75.9% of patients had increased fat mass (FM), with 51.7% having an increase despite normal body mass index. Ambulation was the most important discriminating factor of body composition. 93.1% of patients had metabolic abnormalities, including hyperglycemia, insulin resistance, and dyslipidemia. Increased BHB, a marker of ketosis, was present in more than a third of patients. Functional hypogonadism was present in half of male patients. Testosterone and IGF‐1 negatively correlated with FM. Discussion Adult patients with SMA had abnormal body composition and highly prevalent metabolic disturbances that might increase cardiometabolic risk. Because treatments have modified the course of SMA, it is important to investigate whether these observations translate into clinically relevant outcomes.