Preoperative malnutrition as an independent risk factor for the postoperative mortality in elderly Chinese individuals undergoing hip surgery: a single-center observational study

Abstract

Objective: Malnutrition is prevalent in elderly with hip fracture and higher than in community-dwelling older adults. Scarce studies have examined the association between preoperative malnutrition and postoperative mortality in elderly Chinese individuals with hip fracture. This study was designed to explore the effect of preoperative malnutrition on the postoperative long-term mortality in elderly Chinese individuals undergoing hip surgery. Methods: As a single-center observational study, this study included 263 consecutive patients above 70 years old with hip fracture and elective surgery. Preoperative nutritional status was evaluated by prognostic nutritional index (PNI). Patients were divided into one group with malnutrition (26 patients with PNI ⩽ 38) and the other group without malnutrition (169 patients with PNI > 38), respectively. Results: The overall malnutrition rate was 13.3% (26 patients). The postoperative long-term mortality rates of patients with and without malnutrition had statistically significant difference [10 patients (38.5%) and 32 patients (18.9%), p < 0.05]. Cox regression analysis showed that malnutrition (hazard ratio: 0.269, 95% confidence interval: 0.085–0.859, p < 0.05) and partial pressure of carbon dioxide (hazard ratio: 0.873, 95% confidence interval: 0.790–0.964, p < 0.05) were independent risk factors for the postoperative long-term mortality. Conclusion: This study demonstrated that preoperative malnutrition was an independent risk factor for the postoperative long-term mortality and resulted in a more than 2.5-fold increase of the postoperative long-term mortality in elderly Chinese individuals undergoing hip surgery.