Metabolic Syndrome as a Risk Factor for Postoperative Complication in Patients Undergoing Spine Surgery: A Systematic Review and Meta-Analysis of More Than 3 Million Cases.

OBJECTIVE: Including conditions like obesity, diabetes, hypertension, and dyslipidemia, metabolic syndrome disrupts metabolic homeostasis and impairs recovery, increasing the risk of surgical complications. This study evaluates the impact of metabolic syndrome on spine surgery outcomes, addressing inconsistencies in the existing literature. METHODS: Four databases were searched until December 2024 for studies comparing the postoperative complication rates of spine surgeries between patients with and without metabolic syndrome. Following deduplication, 2 authors independently reviewed the studies. For each included study, demographics and incidence rates of postoperative complications were extracted separately by 2 authors. Data analysis was performed using R. RESULTS: After deduplication, 115 studies were evaluated for inclusion in our study. Following the review of full texts, 11 studies were included. No significant differences were found between patients with and without metabolic syndrome in terms of mortality and nonhome discharge, pulmonary thromboendarterectomy, pneumonia, and sepsis (P > 0.05). However, metabolic syndrome was associated with a significantly increased risk of 30-day readmission (RR: 1.5, 95% CI: 1.2-1.8), reoperation (RR: 1.3, 95% CI: 1.1-1.6), cardiac complications (RR: 1.7, 95% CI: 1.5-2.1), respiratory complications (RR: 1.68, 95% CI: 1.17-2.40), cerebrovascular complications (RR: 2.0, 95% CI: 1.4-2.9), renal complications (RR: 4.48, 95% CI: 2.58-7.80), urinary complications (RR: 1.45, 95% CI: 1.41-1.48), venous thromboembolism (RR: 1.3, 95% CI: 1.1-1.6), and wound complications (RR: 1.6, 95% CI: 1.3-1.9). CONCLUSIONS: Metabolic syndrome might significantly increase the risk of some postoperative complications in spine surgery patients. These findings highlight the need for personalized preoperative planning and management strategies to mitigate surgery risks. CLINICAL RELEVANCE: Identifying and optimizing metabolic syndrome components before surgery may improve patient outcomes and reduce complication rates.