Abstract
BACKGROUND: The clinical impact of obesity on postoperative outcomes of patients undergoing thyroidectomy remains controversial. METHODS: Patients aged ≥ 18 years who were diagnosed with thyroid malignancy and underwent thyroidectomy between 2016 and 2020 were included, and divided into two groups: patients with body mass index (BMI) < 30 kg/m(2) and those with BMI ≥ 30 kg/m(2). Patients in the obese group were then subdivided into four groups: Group 1 (BMI 30.0-34.9 kg/m(2)), Group 2 (BMI 35.0-39.9 kg/m(2)), Group 3 (BMI 40.0-44.9 kg/m(2)), and Group 4 (BMI ≥ 45.0 kg/m(2)) to evaluate the association between degree of obesity and clinical outcomes. We performed propensity score matching, compared outcome variables between the groups, and conducted adjusted multivariate logistic regression analyses of postoperative outcomes. RESULTS: A total of 6778 patients diagnosed with thyroid cancer who underwent thyroidectomy were screened, of whom 1299 (19.2%) patients were obese. Patients in the obese group had higher total hospital charges (p < 0.001) and an increased risk of overall postoperative complications (34.7% vs. 30.5%, p = 0.023). Specifically, patients in the obese group had increased odds of respiratory complication (adjusted odds ratio (aOR) 1.66, 95% confidence interval (CI) [1.26-2.19]), acute renal failure (aOR 1.87, 95% CI [1.13-3.09]), and wound complication (aOR 2.77, 95% CI [1.21-6.37]) than those in the non-obese group. Moreover, trend tests showed that the risks of unfavorable discharge, infection, acute renal failure, and respiratory complication all exhibited an upward trend with increased BMI. CONCLUSION: Obesity is associated with an increased risk of postoperative complications in patients with thyroid cancer undergoing thyroidectomy. This finding suggests that obese patients should be treated with more caution during postoperative recovery.