The Geriatric Nutritional Risk Index Is an Independent Predictor of Adverse Outcomes for Total Joint Arthroplasty Patients.

BACKGROUND: Malnutrition affects patient outcomes after total joint arthroplasty (TJA). Although hypoalbuminemia has been used as a surrogate, there is no unanimous method for screening and assessing malnutrition. This study aimed to determine if malnutrition, as defined by the Geriatric Nutritional Risk Index (GNRI), is independently correlated with short-term (<30 days) postoperative complications and prognosis in patients undergoing TJA. METHODS: The 2016-2019 American College of Surgeons National Surgical Quality Improvement Program was queried for all patients aged >65 years who underwent TJA. Based on GNRI value, patients were divided into 3 groups: normal nutrition (GNRI >98), moderate malnutrition (GNRI 92-98), and severe malnutrition (GNRI <92). After adjusting for potential confounders, multivariable regression models were used to analyze the association between GNRI and patient outcomes. RESULTS: A total of 191,087 patients were included in the study. Prevalence of malnutrition based on body mass index (<18.5 kg/m2), albumin (<3.5 mg/dL), and GNRI (≤98) was 0.41% (784), 4.17% (7975), and 15.83% (30,258). Adjusted analysis showed that compared with normal nutrition, moderate and severe malnutrition status were associated with a higher rate of transfusion, readmission, and postoperative length of stay over 8 days (P < .05). Severe malnutrition was also associated with pneumonia, surgical site infection, urinary tract infection, sepsis, and revision surgery (P < .05). CONCLUSION: Malnutrition, as defined by GNRI, is an independent predictor of adverse outcomes after TJA, including 30-day readmission, revision surgery, and increased length of stay. GNRI can be used to routinely screen and assess patient nutritional status before TJA and counsel patients and families appropriately. LEVEL OF EVIDENCE: Level 3: Retrospective Cohort Study.