Severe malnutrition predicts early postoperative complications in aseptic revision total shoulder arthroplasty

Background: This study investigates the association between the Geriatric Nutritional Risk Index (GNRI), a simple readily available measure of malnutrition risk, and 30-day postoperative complications following revision total shoulder arthroplasty (TSA). Methods: The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients who underwent TSA between 2015 and 2022. The study population was divided into three groups based on preoperative GNRI: normal/reference (GNRI > 98), moderate malnutrition (92 ≤ GNRI ≤ 98), and severe malnutrition (GNRI < 92). Logistic regression analysis was conducted to investigate the connection between preoperative GNRI and postoperative complications. Results: Compared to normal nutrition, moderate malnutrition was not independently associated with postoperative complications. Compared to normal nutrition, severe malnutrition was independently associated with a greater likelihood of experiencing any complication (odds ratio (OR) 3.08, 95% confidence interval (CI) 1.80–5.27; P < 0.001), blood transfusions (OR 3.68, 95% CI 1.40–9.66; P = 0.008), non-home discharge (OR 2.99, 95% CI 1.50–5.98; P = 0.002), and length of stay >2 days (OR 3.10, 95% CI 1.77–5.42; P < 0.001). Discussion: Severe malnutrition based on GNRI is a predictor of early complications following revision TSA, however moderate malnutrition is not.