Background: It is well known that obesity is accompanied by changes in thyroid function. Hypothyroidism is associated with increased body weight. The aim of this study was to evaluate the operative outcomes, weight loss, and the effect of weight loss on thyroid function in morbidly obese patients with hypothyroidism who undergo laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery.
Methods: A retrospective review of 20 morbidly obese female patients with hypothyroidism and on thyroid replacement therapy who underwent LRYGB between January 2003 and August 2006.
Results: Mean preoperative body mass index (BMI) was 47.6 kg/m2 (range 38-58.5 kg/m2). Average patient age was 44.5 years (range 21-66 years). There was one early complication (pneumonia). Late complications included one death, three anastomotic strictures, and one small bowel obstruction. The patients were followed for a mean of 13.5 months (range 3-24 months). Their mean excess body weight loss was 13 kg (22%), 24.4 kg (39.4%), 33.2 kg (63.3%), 38.4 kg (65%), 41.7 kg (70%), and 43 kg (73%) at 1, 3, 6, 9, 12, and 24 months, respectively. Change in a mean BMI was the same regardless of the patient preoperative and postoperative thyroxine dose. Hypothyroidism resolved in 5(25%) patients, improved in 2(10%) patients, unchanged in 8(40%) patients, and worsened in 5 (25%) patients. Most of the five whose hypothyroidism worsened had thyroid autoimmune disease.
Conclusions: Hypothyroidism appears to improve in the vast majority of morbidly obese patients who undergo LRYGB, except for those whose thyroid disease is autoimmune in nature.