The Impact of Malnutrition on Surgical Outcomes in One-Level Lumbar Laminectomy: A Large Propensity-Matched Retrospective Cohort Study

Introduction: The impact of malnutrition, defined by serum albumin < 3.5 g/dL, and its negative impact on surgical outcomes and increased hospital length of stay has been previously reported. However, there is very limited data examining long-term complications of malnutrition in spine surgery. This study evaluates both short- and long-term outcomes in malnourished patients undergoing one-level lumbar laminectomy.

Methods: We utilized the TriNetX database to conduct a retrospective, propensity score-matched analysis of data from 60 US healthcare organizations. Inclusion criteria were patients from 18-90 years old with serum albumin obtained four months prior to one-level lumbar laminectomy in the last 20 years. Patients with an albumin < 3.5 g/dL were assigned to the malnourished cohort and patients with an albumin≥ 3.5 g/dL were assigned to the nourished cohort. Groups were propensity score-matched by age and race. Numerous relevant short-term ( < 90 days) and long-term (>365 days) postoperative outcomes were examined including readmission, infection, spine pain, and subsequent instrumentation removal.

Results: A total of 3,982 patients were identified following propensity score-matching, with 1,991 patients in each cohort. In the short term, malnutrition was associated with increased risk of many negative outcomes compared to nourished cohort including increased readmission (Incidence Risk 32.1% vs 11.4%, p=0.001), sepsis (11.3% vs 2.4%, p=0.001), neurological deficits (5.5% vs 2.2%, p=0.001), acute pulmonary failure (2.8% vs 0.6%, p=0.001), and death (3.5% vs 0.5%, p=0.001). Additionally, malnutrition was associated with increased instrumentation removal in the long term (1.6% vs 0.8%, p=0.013).

Conclusion : Hypoalbuminemia is associated with significantly increased risk of numerous clinically meaningful postoperative complications in the three months following one-level lumbar laminectomy. Additionally, we find increased risk of instrumentation removal in the years following surgery. These data suggest nutritional evaluation and optimization prior to one-level lumbar laminectomy may improve outcomes; however, further prospective research is required to guide specific recommendations for nutritional optimization.