Preoperative Nutritional Status Screened by MNA-SF Predicts Major Complications in Elderly Patients Undergoing Lumbar Fusion Surgery

Purpose: To investigate the role of Mini Nutritional Assessment-Short Form (MNA-SF) in predicting postoperative complications in older patients (≥75 years) undergoing lumbar fusion surgery. Patients and Methods: Patients who had undergone posterior lumbar fusion surgery between June 2019 and September 2021 were enrolled. Those with an MNA-SF score of 12 or higher were categorized as the Nourished group, while those with a score less than 12 were placed in the Malnutrition-Risk group. Preoperative, intraoperative, and postoperative variables between groups were compared. Patients were then re-classified based on the presence of major complications, univariate analysis and multivariate logistic regression was used to identify risk factors for major complications. Results: A total of 240 patients were enrolled, with 182 in the Nourished group and 58 in the Malnutrition-Risk group. The Malnutrition-Risk group exhibited a higher incidence of major complications (46.6% vs 23.1%, p = 0.001) and comprehensive complications index (18.42 ± 18.00 vs 12.65 ± 15.87, p = 0.021), Oswestry Disability Index (27.52 ± 23.44 vs 20.45 ± 20.42, p = 0.029) and longer recovery times (12.53 days vs 10.15 days, p =0.033). Length of stay (LOS) were also increased in the Malnutrition-Risk group (19.22 ± 10.67 vs 16.04 ± 7.69, p = 0.014). Multiple regression analysis identified nutritional risk and malnutrition, as assessed by MNA-SF, as independent factors associated with postoperative major complications (OR 2.81, 95% CI 1.42-5.53, p = 0.003). Conclusion: Preoperative nutritional risk or malnutrition is an independent risk factor for major complications among older patients undergoing posterior lumbar fusion surgery. The MNS-SF emerges as a convenient and effective tool for promptly screening the nutritional status of older patients, prompting subsequent nutritional evaluation or intervention before surgery.