Analysis of combined indicators for risk of osteoporotic hip fractures in elderly women

Abstract Background Hip fractures in the elderly population has become a global issue due to its high morbidity and mortality. Although an increasing number of researchers are devoting attention to identify risk factors in attempts to reduce the incidence of hip fractures in the elderly, only few studies have investigated combined indicators in elderly hip fractures. The objective of the present study was to compare the accuracy of combined independent risk factors in assessing the risk of hip fractures in elderly women. Methods Ninety elderly females who sustained hip fractures and 110 female outpatients who fulfilled the inclusion criteria were included in our cross-sectional study. Bone mineral density (BMD), Beta-carboxy terminal telopeptide(β-CTX), N-terminal/mid region (N-MID), and 25(OH)D levels were analyzed. A novel evaluation model was established to evaluate combined indicators in assessing hip fractures in elderly women. Results Compared with the control group, taller height, higher levels of β-CTX, and lower levels of total hip BMD, femoral neck BMD, and 25(OH)D were found in the facture group. After adjustment for confounding factors, logistic regression analysis revealed that 25(OH)D, femoral neck BMD and height remained risk factors for hip fractures in elderly women. Then a model including independent risk factors was established. DeLong test showed the area under the ROC(AUC) of 25(OH)D was significantly greater than that for femoral neck BMD (p < 0.01) and height (p < 0.01). AUC of model including 25(OH)D and height was significantly greater than that of other combinations (p < 0.01). Conclusion 25(OH)D, femoral neck BMD and height were associated with the occurrence of hip fractures in elderly women even after adjustment for confounding factors, and model including 25(OH)D and height could provide better associated power than other combinations in the assessment of elderly hip fractures. β-CTX and N-MID were not independent risk factors for hip fractures in elderly women.