Association of Malnutrition with Surgical Outcomes After Spine Surgery for Spinal Epidural Abscess

Introduction: Malnutrition has been shown to be a predictor of poor surgical outcomes but its specific effects in spinal epidural abscess (SEA) is understudied. This study aims to assess the potential association between nutritional status and post-operative outcomes, as measured by extended length of stay (LOS), adverse events (AEs), non-routine discharge (NRD), and 30-day mortality.

Methods: We conducted a retrospective cohort study using the 2011-2022 American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database to identify adult patients who underwent spinal surgery for SEA. The study population was divided into two groups: Nourished (preoperative serum albumin values ≥ 3.5 g/dL) and Malnourished (preoperative serum albumin values < 3.5 g/dL). Multivariable logistic regression analyses were performed to identify factors associated with extended LOS, AEs, NRD, 30-day unplanned reoperation, and mortality.

Results: 1,462 adults were stratified by nutrition status: 300 Nourished (20.5%) and 1162 Malnourished (79.5%). The Malnourished cohort had a significantly higher incidence of severe medical AEs (Nourished: 42.7% vs. Malnourished: 55.9, p< 0.001), including ventilator requirement (Nourished: 4.7% Malnourished: 10.8%, p=0.001), DVT (Nourished: 1.3% vs. Malnourished: 4.2%, p=0.017), and septic shock (Nourished: 4.3% vs. Malnourished: 8.9%, p=0.010); conversely, no significant difference was noted for surgical AEs. Malnourished patients also had significantly longer LOS (Nourished: 11.0 ± 7.4 days vs. Malnourished: 16.0 ± 11.8 days, p< 0.001), increased incidence of NRD (Nourished: 50.3% vs. Malnourished: 72.5%, p< 0.001), higher 30-day mortality (Nourished: 2.0% vs. Malnourished: 4.8%, p=0.031), and higher 30-day reoperation (Nourished: 9.3% vs. Malnourished: 16.5%, p=0.002). On multivariate analysis, malnourishment was significantly associated with an increased risk of extended LOS (2.47 (1.65-3.71), p< 0.001) AEs (1.41 (1.08-1.83), p=0.011), and NRD (1.93 (1.44-2.58), p< 0.001), but was not significantly associated with 30-day unplanned reoperation or mortality.

Conclusion : The results of our study indicate that malnourishment is significantly associated with worse post-surgical outcomes for patients with SEA. Further investigation is necessary to assess this relationship and identify interventions for mitigating the negative effects of malnourishment in operative therapy for SEA.