Risk factors for surgical site infection following thyroid surgery: a systematic review and meta-analysis

Thyroid surgery is a common surgical procedure for the treatment of thyroid diseases, such as thyroid nodules, thyroid cancer, and hyperthyroidism. Despite significant advancements in surgical techniques and perioperative care, surgical site infection (SSI) remains a frequent postoperative complication, which can lead to prolonged hospital stays, increased medical costs, and decreased quality of life for patients. Identifying risk factors for SSI is crucial for developing effective prevention strategies. This study aimed to systematically investigate and quantify the incidence and risk factors associated with SSI following thyroid surgery through a meta-analysis and systematic review.

A comprehensive search strategy was employed across major databases [PubMed, Web of Science, Embase, Cochrane Library, China Biology Medicine (CBM), China National Knowledge Infrastructure (CNKI), Wanfang Data] up to June 15, 2024. Additionally, we conducted a supplementary search for relevant literature up to October 4, 2024. Studies were selected based on stringent inclusion and exclusion criteria focusing on SSI risk factors in patients undergoing thyroid surgery. The methodological quality of eligible studies was critically appraised. Statistical analyses were conducted using Stata 15.1 with meta-analytic techniques to estimate means and standard deviations, and calculating odds ratio (OR) with 95% confidence interval (CI) using appropriate effect models. Publication bias was assessed using Egger's test.

The systematic review and subsequent meta-analysis included nine studies (eight case-control and two cohort) involving a total of 127,467 patients, with 703 cases of postoperative SSI documented. Key findings indicated that prolonged surgical duration greater than 2 hours [OR =4.50; 95% CI: (2.74, 7.37); P<0.001], presence of comorbidities [OR =1.91; 95% CI: (1.16, 3.15); P=0.01], age greater than 50 years [OR =1.81; 95% CI: (1.24, 2.64); P=0.002], incision length greater than 5 cm [OR =2.79; 95% CI: (1.92, 4.04); P<0.001], lymph node dissection [OR =1.90; 95% CI: (1.28, 2.80); P=0.001], and male [OR =1.78; 95% CI: (1.38, 2.29); P<0.001] were significant risk factors for SSI after thyroid surgery. Conversely, male gender did not present a statistically significant association with SSI risk.

Surgical duration greater than 2 hours, presence of comorbidities, age greater than 50 years, incision length greater than 5 cm, lymph node dissection, and male emerge as critical risk factors for SSI in patients recovering from thyroid surgery. However, the small number of included articles and the lack of differentiation between OR, risk ratio (RR), and hazard ratio (HR) are limitations of this analysis.