Prognosis prediction after hip fracture surgery: independent validation and recalibration of the Nottingham Hip Fracture Score
10.3760/cma.j.cn115530-20230718-00003
- VernacularTitle:髋部骨折手术预后的预测：Nottingham髋部骨折评分的独立验证和重新校准
- Author:
Yongjun JIN
1
;
Peng XIAO
;
Xu ZHU
;
Bingtao ZHAO
;
Xinfeng LIANG
;
Xuejian WU
Author Information
1. 郑州大学第一附属医院骨科，郑州 450052
- Keywords:
Hip fractures;
Mortality;
Nottingham hip fracture score;
Forecasting
- From:
Chinese Journal of Orthopaedic Trauma
2023;25(9):777-784
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the application value of the Nottingham Hip Fracture Score (NHFS) in China and establish a formula specifically designed to assess the risk for 30-day mortality after surgery for hip fracture patients in China.Methods:A retrospective study was conducted to analyze the clinical data of 824 hip fracture patients who had been treated at Department of Orthopaedics, The First Hospital Affiliated to Zhengzhou University from August 2019 to May 2022. There were 312 males and 512 females with a median age of 73 (63, 82) years. The clinical data were compared between patients with different survival outcomes. The 30-day mortality was calculated by the formula according to the patients' NHFS, and compared with the actual one to validate the effectiveness of the original prediction model. The patients were divided into a training group ( n=577) and a validation group ( n=247). Binary logistic regression analysis was performed to establish a new prediction model for the patients in the training group. The discrimination, calibration, and clinical effectiveness of the predictive model were assessed in both the training and validation groups. Results:Multivariate logistic regression analysis showed that advanced age (≥86 years old) ( OR=3.775, 95% CI: 1.099 to 12.972, P=0.035), male ( OR=3.151, 95% CI: 1.574 to 6.306, P=0.001), admission hemoglobin concentration ≤100 g/L ( OR=2.402, 95% CI: 1.189 to 4.850, P=0.015), dependence on others for care before admission ( OR=2.673, 95% CI: 1.298 to 5.505, P=0.008), and comorbidities ≥2 ( OR=4.988, 95% CI: 1.874 to 13.274, P=0.001) were identified as risk factors for postoperative 30-day mortality (all P<0.05). In validation of the original prediction model, the C-index was found to be 0.764, indicating good discrimination. However, there was a significant discrepancy between the mortality forecast by the original prediction model and the actual mortality ( P<0.05), indicating poor calibration. After the prediction model was recalibrated, 30-day mortality (%) = 100/[1 + e (5.818-NHFS×0.599)]. After the new prediction model was validated in both the training and validation groups, the C-indexes were 0.762 and 0.780, indicating a good level of discrimination. The predicted 30-day mortality by the prediction model was closely aligned with the actual mortality ( P>0.05), demonstrating good calibration. When the threshold probabilities of the training and the validation groups were 0 to 26% and 0 to 35%, respectively, the patients might benefit from clinical intervention, showing clinical effectiveness of the model. Conclusions:The NHFS can predict the risk for 30-day mortality after hip fracture surgery. The new NHFS prediction model after calibration has a good predictive value for 30-day mortality after hip fracture surgery in Chinese population.
