Obese elderly patients with hip fractures may have better survival outcomes after surgery
Hao Wang, Liping Pan, Baoqiang Li, Taiguo Ning, Guanghua Liang, Yongping Cao
Abstract
BACKGROUND: In recent years, there has been an increasing amount of research on the "obesity paradox". So our primary objective was to explore whether this phenomenon exists in our study, and secondary objective was to determine the effect of body mass index (BMI) on major complications, and the incidence of acute kidney injury (AKI) after hip fracture surgery after controlling for confounding factors. METHODS: ). We analyzed demographic characteristics, operation information and postoperative outcomes. Using multivariate regression with normal-weight patients as the reference, we determined the odds of 1-year mortality, major complications, and AKI by BMI category. RESULTS: A total of 644 patients were included. Nine percent of patients died after 1 year, 18% had major postoperative complications, and 12% had AKI. There was a U-shaped relationship between BMI and the rates of major complications or AKI. However, there was a linear decreasing relationship between 1-year mortality and BMI. After controlling for confounding factors, multivariate regression analysis showed that the risk of 1-year mortality after surgery was 2.24 times higher in underweight patients than in normal-weight patients (P < 0.05, OR: 2.24, 95% CI 1.14-4.42). Compared with normal-weight patients, underweight patients had a 2.07 times increased risk of major complications (P < 0.05, OR 2.07, 95% CI 1.21-3.55), and the risk of major complications in obese patients was 2.57 times higher than that in normal-weight patients (P < 0.05, OR 2.57, 95% CI 1.09-6.09). Compared with normal-weight, underweight patients had a 2.18 times increased risk of AKI (P < 0.05, OR 2.18, 95% CI 1.17-4.05). CONCLUSIONS: The 1-year mortality risk of patients with higher BMI was significantly reduced. Besides, compared with normal-weight patients, underweight patients and obese patients have a higher risk of major complications; low-weight and obese patients are at higher risk for AKI.