Impact of bariatric surgery on morbidly obese hypothyroid patients

Abstract

Background Obesity is considered a risk factor for many health issues, which includes cardiovascular, psychological, neurological, and musculoskeletal diseases. It is known that overt hypothyroidism induces obesity if not properly managed. The aim of current study is to evaluate effect of different bariatric surgeries on morbidly obese hypothyroid patients regarding thyroid-stimulating hormone, free T4, and dose of levothyroxine supplement needed. Patients and methods A retrospective cohort study was conducted on patients with morbid obesity and hypothyroidism from January 2021 to January 2023. We included patients more than 18 years old, obese (BMI >40 kg/m2 or >35 kg/m2 in association with uncontrolled comorbidities such as diabetes, hypertension, hyperlipidemia, and obstructive sleep apnea) with hypothyroidism undergoing bariatric surgery. Secondary objectives include assessment of weight reduction after bariatric surgery as excess weight loss and excess body mass index loss. Results The mean excess weight loss was 44.2%, while the mean excess body mass index loss was 88.22%. Sleeve gastrectomy surgery had the highest percentage of patients who reduced their thyroid hormone replacement (THR) dose (61.9%), followed by the Mini Gastric Bypass (MGB) group (47.5%). The Roux-en-Y Gastric Bypass (RGB) group had the highest percentage of patients who were off their THR dose (56.3%), followed by the sleeve group (31.8%). Only one (4.5%) patient in the sleeve group had an increased THR dose. Conclusions Bariatric surgery has a significant impact on the THR dose in patients with hypothyroidism. The type of surgery also affects the percentage of patients who reduced, stopped, or maintained their THR dose.