Assessing perioperative body weight changes in patients thyroidectomized for a benign nontoxic nodular goitre

Following thyroidectomy, patients often complain of weight gain. Our study aimed to evaluate the extent of weight change in patients thyroidectomized for a nontoxic benign goitre after adjusting for patient demographics and pre-operative weight changes.

Three different patient groups were studied. The first comprised 898 patients who underwent thyroidectomy for benign nontoxic nodular goitre (group I). The second comprised 179 patients who had benign nontoxic goitre but did not undergo thyroidectomy (group II), and the third comprised 80 patients who underwent a simple excision of a parathyroid adenoma (group III). All patients were weighed 12 months preceding baseline, at baseline and 6 months after baseline.

Baseline characteristics were comparable between groups. Patients in Group I who gained the least weight in the year leading to surgery gained the most weight 12 months after surgery (P = 0·030). After adjusting for demographics and pre-operative weight changes, Group I gained significantly more weight at post 6 and 12 months (0·71 (95% CI=0·46-0·95) kg and 1·21 (95% CI = 0·96-1·46) kg, respectively). Weight gain at post 12 months appeared similar between hemithyroidectomy and total thyroidectomy (1·32 vs 1·16 kg, P = 0·197). Younger age (ß coefficient -0·100, 95% CI = -0·030 to 0·003, P = 0·015) and higher baseline thyroid stimulating hormone (ß coefficient -0·315, 95% CI = -1·468 to 0·134, P = 0·020) were significant factors for weight gain at post 12 months.

Compared to nonthyroidectomized patients, thyroidectomized patients experienced significant weight increases at post 6 and 12 months. The extent of thyroidectomy did not affect the extent of weight gain. Younger age and higher baseline thyroid stimulating hormone were significant factors of weight gain at post 12 months.