Evaluation of Nottingham Hip Fracture Score, Age-Adjusted Charlson Comorbidity Index and the Physiological and Operative Severity Score for the enumeration of Mortality and morbidity as predictors of mortality in elderly neck of femur fracture patients

Risk scoring models for patients with proximal femur fractures: Qualitative systematic review assessing 30-day mortality and ease of use

BACKGROUND

Hip fractures are a common orthopaedic injury affecting a particularly frail and vulnerable patient cohort. They are at risk of many complications, including prolonged length of stay and mortality. Efforts to identify those at high risk may be beneficial. Over 25 risk prediction models are published for patients with hip fractures.

AIM

The primary aim of this study was to assess the performance of predictor scores in predicting 30-day mortality. The secondary aim was to assess the ease of use of these systems.

METHODS

A qualitative systematic review was performed. A search was conducted on online databases, including PubMed, CINAHL, Clinical Trials.gov, Cochrane, DARE, EMBASE, SCOPUS, and Web of Science.. The terms fragility hip fractures and risk prediction models were utilised while performing the search. These were then expanded using Boolean operators and similar terms. Search results were imported to Covidence. Primary observational studies using one or more hip fracture mortality prediction models and 30-day mortality as an outcome were included. Systematic reviews and studies on specific patient groups defined other medical conditions (e.g. COVID positive or dialysis patients) were excluded.

RESULTS

3,101 studies were screened following duplicate removal. 34 papers were included in the review, in which 23 scoring systems were reported. Six of these were pre-operative and reported in multiple studies. Most demonstrated appropriate fit and fair discrimination. Five of the six pre-operative scoring systems examined, displayed appropriate ease of use, allowing risk calculation at the time of admission.

CONCLUSION

Nottingham Hip Fracture Score remains the most extensive reported scoring system and performs fair overall with AUROCs of 0.64-0.80 and good fit in calibration across all studies. However, new systems utilise many similar predictors. There is a need for the standardisation of publications on scoring systems to allow further systematic review and meta-analyses.

Validation and updating of the Older Person's Emergency Risk Assessment (OPERA) score to predict outcomes for hip fracture patients

INTRODUCTION

Hip fractures are associated with significant morbidity and mortality in older people. Accurate risk stratification is important for planning of care, informed decision-making and communication with patients and relatives. The Older Persons' Emergency Risk Assessment (OPERA) score is a risk stratification score for older people admitted to hospital. Our aims were to validate OPERA in hip fracture patients, update the score and compare performance with the Nottingham Hip Fracture Score (NHFS).

METHODS

This dual-centre 3-year observational study (2016-2018) included acutely admitted hip fracture patients managed surgically aged ⩾65 years. The primary outcome was 30-day mortality. Secondary outcomes included residence at 120 days and 1-year mortality. Model performance was assessed using area under the curve (AUC) analysis and Brier scores (discrimination) and calibration curves. The OPERA score was updated using regression analysis with additional independent predictors and validated using bootstrap analysis.

RESULTS

2142 patients (median age 86 [80-91] years) were included with a 30-day mortality of 5.2% and a 1-year mortality of 31.4%. 30-day mortality AUC for OPERA was 0.75 (95% CI, 0.73-0.77) and for NHFS 0.68 (0.65-0.70). For 1-year mortality AUC for OPERA was 0.74 (0.73-0.75) and for NHFS 0.70 (0.69-0.71). The OPERA Score was updated to Hip-OPERA, including ASA grade. Hip-OPERA demonstrated an AUC for 30-day mortality of 0.77 (0.73-0.81) and an AUC for 1-year mortality of 0.76 (0.75-0.77). AUC for new residential care status at 120 days was 0.79 (0.78-0.80).

CONCLUSIONS

Hip-OPERA demonstrated superior discrimination to the NHFS and OPERA for 30-day mortality, 1-year mortality and residence at 120 days following hip fracture. External validation is desirable.

Predictors of one-year mortality following hip fracture surgery in elderly

Background

Understanding mortality risk factors is critical to reducing mortality among elderly hip fracture patients. To investigate the effects of admission and post-operative levels of distribution width of red blood cells (RDW), albumin, and RDW/albumin (RA) ratio on predicting 1-year mortality following hip fracture surgery.

Methods

A retrospective study was conducted on 275 elderly patients who underwent hip fracture surgery in a tertiary hospital between January 2018 and January 2022. Deaths within one year of hip fracture were defined as the deceased group. The survivors were defined as those who survived for at least one year. The relationship between admission and post-operative levels of RDW, albumin, RA, and mortality within one year after hip surgery was assessed statistically, including binary logistic regression analysis. The study also assessed other factors related to mortality.

Results

One-year mortality was 34.7%. There was a 3.03-year (95% CI [1.32-4.75]) difference between the deceased (79.55 ± 8.36 years) and survivors (82.58 ± 7.41 years) (p < 0.001). In the deceased group, the mean hemoglobin (HGB) values at admission (p = 0.022) and post-operative (p = 0.04) were significantly lower. RDW values at admission (p = 0.001) and post-op (p = 0.001) were significantly lower in the survivor group. The mean albumin values at admission (p < 0.001) and post-operative (p < 0.001) in the survivor group were significantly higher than in the deceased group. A significant difference was found between the survivor group and the deceased group in terms of mean RA ratio at admission and post-operative (p < 0.001). Based on binary logistic regression analysis, presence of chronic obstructive pulmonary disease (COPD) (OR 3.73, 95% CI [1.8-7.76]), RDW (OR 1.78, 95% CI [1.48-2.14]), and albumin (OR 0.81, 95% CI [0.75-0.87]), values at admission were found to be independent predictors of 1-year mortality in elderly patients with hip fracture.

Conclusion

Based on this study, presence of COPD, higher RDW, and lower albumin levels at admission were independent predictors of 1-year mortality following hip fracture surgery in the elderly.

Use of the Shizuoka Hip Fracture Prognostic Score (SHiPS) to Predict Long-Term Mortality in Patients With Hip Fracture in Japan: A Cohort Study Using the Shizuoka Kokuho Database

Hip fractures are common in patients of advanced age and are associated with excess mortality. Rapid and accurate prediction of the prognosis using information that can be easily obtained before surgery would be advantageous to clinical management. We performed a population-based retrospective cohort study using an 8.5-year Japanese claims database (April 2012-September 2020) to develop and validate a predictive model for long-term mortality after hip fracture. The study included 43,529 patients (34,499 [79.3%] women) aged ≥65 years with first-onset hip fracture. During the observation period, 43% of the patients died. Cox regression analysis identified the following prognostic predictors: sex, age, fracture site, nursing care certification, and several comorbidities (any malignancy, renal disease, congestive heart failure, chronic pulmonary disease, liver disease, metastatic solid tumor, and deficiency anemia). We then developed a scoring system called the Shizuoka Hip Fracture Prognostic Score (SHiPS); this system was established by scoring based on each hazard ratio and classifying the degree of mortality risk into four categories based on decision tree analysis. The area under the receiver operating characteristic (ROC) curve (AUC) (95% confidence interval [CI]) of 1-year, 3-year, and 5-year mortality based on the SHiPS was 0.718 (95% CI, 0.706-0.729), 0.736 (95% CI, 0.728-0.745), and 0.758 (95% CI, 0.747-0.769), respectively, indicating good predictive performance of the SHiPS for as long as 5 years after fracture onset. Even when the SHiPS was individually applied to patients with or without surgery after fracture, the prediction performance by the AUC was >0.7. These results indicate that the SHiPS can predict long-term mortality using preoperative information regardless of whether surgery is performed after hip fracture.

Predictability of Neutrophil to Lymphocyte Ratio in preoperative elderly hip fracture patients for post-operative short-term complications: a retrospective study

PURPOSE

Neutrophil to Lymphocyte Ratio (NLR) is a simple biomarker of systemic inflammatory response. We investigated predictability of NLR for early adverse outcome after surgery for hip fracture in elderly population.

METHODS

We reviewed a total of 971 elderly patients with hip fracture who underwent emergency surgery between January 2017 and July 2020 in the Department of Orthopaedics Surgery at the Wollongong Hospital. After considering exclusion criteria, data from a total of 834 patients included in our study. Socio-demographic data, NLR in admission, updated Charlson comorbidity index (uCCI), biochemical markers, mortality rate and 15 short term post-operative complications were collected to determine predictability of NLR for post-operative complications and mortality.

RESULTS

After hip surgery, Hospital in-patient case fatality rate was 3.7% (31). In addition, 63.1% (511) of the patients had at least one complication or more. Logistic regression demonstrated that raised NLR (P-value < 0.001, OR 1.05) and uCCI≥4 (P-Value < 0.001, OR 1.75) are associated with post-operative complications. Moreover, decreased haemoglobin was associated with adverse effects (P-value < 0.001, OR 0.97). No association was found for any of these variables with in-patient mortality except for albumin (P-value: 0.03). In addition, despite significant association, ROC analyses showed a low predictability for each of the above variables including NLR (AUC 0.59) for post-operative complications.

CONCLUSIONS

Despite significant association, NLR was unable to prognosticate early adverse outcomes. However, it can be considered as a risk factor in admission for postoperative complications in combination with other risk factors and clinical context.

Validation of the Nottingham Hip Fracture Score in Predicting Postoperative Outcomes Following Hip Fracture Surgery

OBJECTIVE

Although several prognostic models have been developed for patients who underwent hip fracture surgery, their preoperative performance was insufficiently validated. We aimed to verify the effectiveness of the Nottingham Hip Fracture Score (NHFS) for predicting postoperative outcomes following hip fracture surgery.

METHODS

This was a single-center and retrospective analysis. A total of 702 elderly patients with hip fractures (age ≥ 65 years old) who received treatment in our hospital from June 2020 to August 2021 were selected as the research participants. They were divided into the survival group and the death group based on their survival 30 days after surgery. The multivariate logistic regression model was used to identify the independent risk factors for the 30-day mortality after surgery. The NHFS and American Society of Anaesthesiologists (ASA) grades were used to construct these models, and a receiver operating characteristic curve was plotted to assess their diagnostic significance. A correlation analysis was performed between NHFS and length of hospitalization and mobility 3 months after surgery.

RESULTS

There were significant differences in the age, albumin level, NHFS, and ASA grade between both groups (p < 0.05). The length of hospitalization in the death group was longer than the survival group (p < 0.05). The perioperative blood transfusion and postoperative ICU transfer rates in the death group were higher than in the survival group (p < 0.05). The death group's incidence of pulmonary infections, urinary tract infections, cardiovascular events, pressure ulcers, stress ulcers with bleeding, and intestinal obstruction was higher than the survival group (p < 0.05). The NHFS and ASA III were independent risk factors for the 30-day mortality after surgery, regardless of age and albumin level (p < 0.05). The area under the curve (AUC) of the NHFS and ASA grade for predicting the 30-day mortality after surgery was 0.791 (95% confidence interval [CI] 0.709-0.873, p < 0.05) and 0.621 (95% CI 0.477-0.764, p > 0.05), respectively. The NHFS positively correlated with hospitalization length and mobility grade 3 months after surgery (p < 0.05).

CONCLUSION

The NHFS demonstrated a better predictive performance than the ASA score for the 30-day mortality after surgery and positively correlated with the hospitalization length and postoperative activity limitation in elderly patients with hip fractures.

Comparison of Prognostic Value of 10 Biochemical Indices at Admission for Prediction Postoperative Myocardial Injury and Hospital Mortality in Patients with Osteoporotic Hip Fracture

Aim: To evaluate the prognostic impact at admission of 10 biochemical indices for prediction postoperative myocardial injury (PMI) and/or hospital death in hip fracture (HF) patients. Methods: In 1273 consecutive patients with HF (mean age 82.9 ± 8.7 years, 73.5% women), clinical and laboratory parameters were collected prospectively, and outcomes were recorded. Multiple logistic regression and receiver-operating characteristic analyses (the area under the curve, AUC) were preformed, the number needed to predict (NNP) outcome was calculated. Results: Age ≥ 80 years and IHD were the most prominent clinical factors associated with both PMI (with cardiac troponin I rise) and in-hospital death. PMI occurred in 555 (43.6%) patients and contributed to 80.3% (49/61) of all deaths (mortality rate 8.8% vs. 1.9% in non-PMI patients). The most accurate biochemical predictive markers were parathyroid hormone > 6.8 pmol/L, urea > 7.5 mmol/L, 25(OH)vitamin D < 25 nmol/L, albumin < 33 g/L, and ratios gamma-glutamyl transferase (GGT) to alanine aminotransferase > 2.5, urea/albumin ≥ 2.0 and GGT/albumin ≥ 7.0; the AUC for developing PMI ranged between 0.782 and 0.742 (NNP: 1.84−2.13), the AUC for fatal outcome ranged from 0.803 to 0.722, (NNP: 3.77−9.52). Conclusions: In HF patients, easily accessible biochemical indices at admission substantially improve prediction of hospital outcomes, especially in the aged >80 years with IHD.

Developing and validating a scoring system for measuring frailty in patients with hip fracture: a novel model for predicting short-term postoperative mortality

Objectives

Frailty is common among patients with hip fracture and may, in part, contribute to the increased risk of mortality and morbidity after hip fracture surgery. This study aimed to develop a novel frailty score for patients with traumatic hip fracture that could be used to predict postoperative mortality as well as facilitate further research into the role of frailty in patients with hip fracture.

Methods

The Orthopedic Hip Frailty Score (OFS) was developed using a national dataset, retrieved from the Swedish National Quality Registry for Hip Fractures, that contained all adult patients who underwent surgery for a traumatic hip fracture in Sweden between January 1, 2008 and December 31, 2017. Candidate variables were selected from the Nottingham Hip Fracture Score, Sernbo Score, Charlson Comorbidity Index, 5-factor modified Frailty Index, as well as the Revised Cardiac Risk Index and ranked based on their permutation importance, with the top 5 variables being selected for the score. The OFS was then validated on a local dataset that only included patients from Orebro County, Sweden.

Results

The national dataset consisted of 126,065 patients. 2365 patients were present in the local dataset. The most important variables for predicting 30-day mortality were congestive heart failure, institutionalization, non-independent functional status, an age ≥85, and a history of malignancy. In the local dataset, the OFS achieved an area under the receiver-operating characteristic curve (95% CI) of 0.77 (0.74 to 0.80) and 0.76 (0.74 to 0.78) when predicting 30-day and 90-day postoperative mortality, respectively.

Conclusions

The OFS is a significant predictor of short-term postoperative mortality in patients with hip fracture that outperforms, or performs on par with, all other investigated indices.

Level of evidence

Level III, Prognostic and Epidemiological.

Validation of the Nottingham Hip Fracture Score (NHFS) for the prediction of 30-day mortality in a Swedish cohort of hip fractures

BACKGROUND

Hip fracture is a common osteoporotic fracture with great morbidity and mortality. The utility of ASA classification is limited, as most patients are ≥ASA 3. A reliable predictor of mortality risk could support decision-making. We aimed to evaluate Nottingham hip fracture score (NHFS) for the prediction of 30-day mortality and then to recalibrate the formula converting NHFS to risk of 30-day mortality.

METHODS

All patients >60 years with surgically treated hip fracture surgery during 2015-16 were assessed. Data was extracted manually from routinely collected clinical data in registry and medical records. Discriminative performance of NHFS and ASA was assessed with C-statistics. The conversion formula from NHFS to risk of 30-day mortality was recalibrated using logistic binominal regression. Observed vs expected ratios of 30-day mortality were compared with the 2012 NHFS-formula and recalibration was performed in a split dataset.

RESULTS

1864 patients were included, with 213 deaths within 30 days. C-statistic were 0.64 for NHFS and 0.62 for ASA. Comparing expected values from the 2012-revision with our observed deaths gave a ratio of 1.37. Relating predicted levels of 30-day mortality based on 70% of our cohort vs. 30% test portion of our Swedish dataset gave a ratio of 0.97.

DISCUSSION

NHFS underestimated mortality in our cohort and showed poor discrimination. Revision of the formula based on a split dataset improved calibration. We suggest NHFS to be routinely implemented to support clinical judgements, expand preoperative assessment and escalate intraoperative monitoring.

Predictors of In-Hospital Mortality in Older Adults Undergoing Hip Fracture Surgery: A Case-Control Study

Introduction: Although surgery has been proven to improve the long-term survival of older adults with hip fracture, in-hospital mortality directly resulting from repair of hip fracture is undesirable. This study aimed to identify potential prognostic factors that predict in-hospital mortality risk in elderly patients following hip fracture surgery. Materials and Methods: This case–control study comprehensively collected data from older adults with hip fracture admitted to a single medical centre. Age was selected as the cross-matching factor. Univariate and binary multivariate logistic regression models were used to estimate the odds ratios with 95% confidence intervals. A receiver operating characteristic curve was constructed to quantify the discrimination power of the model. Results: Among a total of 841 older adults who received hip fracture surgery, 17 died during hospitalisation, yielding a 2.0% in-hospital mortality rate. Using a binary multivariate logistic regression model to perform a comparison with 51 age-matched patients in survival groups, the model revealed that estimated glomerular filtration rate (eGFR) and malignant cancer history were the only 2 factors significantly correlated with in-hospital mortality. The prognostic values for the eGFR and malignant cancer history were acceptable, with areas under the curve of .76 and .67, respectively. Conclusion: The prevalence of in-hospital mortality following hip fracture is low. After adjustment for age, eGFR and malignant cancer history were identified as factors significantly correlated with in-hospital mortality. The findings of this study could assist in the early screening and detection of patients with high in-hospital mortality risks.

Chin-on-Chest in Neck of Femur Fracture (COCNOF) sign: A simple radiographic predictor of frailty and mortality in hip fracture patients

INTRODUCTION

Fragility fractures are a significant public health challenge often occurring as a result of frailty. Identifying patients who have increased risk of adverse outcomes can aid treating teams in managing these patients appropriately. We hypothesise that the appearance of the patient's head overlapping the lung fields (named Chin on Chest in Neck of Femur sign (COCNOF)) in the admission chest radiograph was a predictor of increased mortality at 3, 6 and 12 months.

METHODS

All consecutive patients admitted with hip fracture between 1^st January - 31st December 2019 were analysed. We collected patient characteristics, AMTS score, ASA grade, length of stay, place of discharge, Nottingham Hip Fracture Score, Rockwood Frailty score, Charlson Comorbidity Index and presence of COCNOF sign. The main outcome measures were mortality at 90 days, six months and 12 months following admission.

RESULTS

469 patients with a mean age of 81.9 (SD 8.4) were included. 18% of patients were COCNOF positive. Univariate analysis showed positive COCNOF sign to be associated with higher mortality at 90 days (19.1 vs 10.8%; RR 1.95, 95%CI 1.05 - 3.63,p=0.03), six months (31.5% vs 14.2%; RR 2.77, 95%CI 1.62 - 4.72, p<0.001) and twelve months (41.6% vs 17.1%; RR 3.45, 95%CI 1.62-4.72, p<0.001). In the multivariate regression models the strongest predictors of mortality were age, gender and CCI it is therefore likely that the COCNOF sign is acting as a surrogate marker of these variables within the univariate models.

CONCLUSION

Our results suggest that COCNOF sign is a simple radiographic marker which can be used to identify patients with higher levels of frailty and increased risk of mortality following hip fracture.

Predictive Values of Preoperative Characteristics for 30-Day Mortality in Traumatic Hip Fracture Patients

Hip fracture patients have a high risk of mortality after surgery, with 30-day postoperative rates as high as 10%. This study aimed to explore the predictive ability of preoperative characteristics in traumatic hip fracture patients as they relate to 30-day postoperative mortality using readily available variables in clinical practice. All adult patients who underwent primary emergency hip fracture surgery in Sweden between 2008 and 2017 were included in the analysis. Associations between the possible predictors and 30-day mortality was performed using a multivariate logistic regression (LR) model; the bidirectional stepwise method was used for variable selection. An LR model and convolutional neural network (CNN) were then fitted for prediction. The relative importance of individual predictors was evaluated using the permutation importance and Gini importance. A total of 134,915 traumatic hip fracture patients were included in the study. The CNN and LR models displayed an acceptable predictive ability for predicting 30-day postoperative mortality using a test dataset, displaying an area under the ROC curve (AUC) of as high as 0.76. The variables with the highest importance in prediction were age, sex, hypertension, dementia, American Society of Anesthesiologists (ASA) classification, and the Revised Cardiac Risk Index (RCRI). Both the CNN and LR models achieved an acceptable performance in identifying patients at risk of mortality 30 days after hip fracture surgery. The most important variables for prediction, based on the variables used in the current study are age, hypertension, dementia, sex, ASA classification, and RCRI.

Predicting 30-Day and 180-Day Mortality in Elderly Proximal Hip Fracture Patients: Evaluation of 4 Risk Prediction Scores at a Level I Trauma Center

This study evaluated the use of risk prediction models in estimating short- and mid-term mortality following proximal hip fracture in an elderly Austrian population. Data from 1101 patients who sustained a proximal hip fracture were retrospectively analyzed and applied to four models of interest: Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM), Charlson Comorbidity Index, Portsmouth-POSSUM and the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP^®) Risk Score. The performance of these models according to the risk prediction of short- and mid-term mortality was assessed with a receiver operating characteristic curve (ROC). The median age of participants was 83 years, and 69% were women. Six point one percent of patients were deceased by 30 days and 15.2% by 180 days postoperatively. There was no significant difference between the models; the ACS-NSQIP had the largest area under the receiver operating characteristic curve for within 30-day and 180-day mortality. Age, male gender, and hemoglobin (Hb) levels at admission <12.0 g/dL were identified as significant risk factors associated with a shorter time to death at 30 and 180 days postoperative (p < 0.001). Among the four scores, the ACS-NSQIP score could be best-suited clinically and showed the highest discriminative performance, although it was not specifically designed for the hip fracture population.