Publication Details
Abstract
Bariatric surgery is the most effective available intervention for achieving substantial and sustained weight loss in patients with severe obesity, and it produces well-documented improvements in multiple obesity-related comorbidities. Among the less widely appreciated effects of bariatric surgery are its consequences for thyroid gland structure and function. Weight loss induced by procedures such as sleeve gastrectomy and Roux-en-Y gastric bypass is consistently associated with a decline in circulating thyroid-stimulating hormone (TSH) toward normal-weight reference values, a reduction in indices of central resistance to thyroid hormone, and — on ultrasonography — a reversal of the hypoechoic, obesity-related pattern of the thyroid parenchyma toward normal echogenicity. This review summarizes the current evidence on the pathomorphological and functional remodeling of the thyroid gland after bariatric surgery, discusses the proposed mechanisms underlying this remodeling, and addresses the practical question of levothyroxine dose adjustment in hypothyroid patients undergoing these procedures.