Abstract
Introduction
Although a previous hip fracture is one of the strongest predictors for the next one this risk might be modified by other factors. The goal of this analysis was to compute a simple algorithm to assess the individual risk for a contralateral hip fracture.
Materials and methods
The analysis is based on a nationwide population-based Danish cohort study of 84,360 patients experiencing a hip fracture followed-up for 5 years. We a priori defined a set of 17 candidate parameters potentially associated with early contralateral hip fracture. We bootstrapped a stepwise augmentation procedure 10 times and selected five parameters that entered the model in all bootstrapping cycles and computed the individual risk for a contralateral fracture within two, three, and five years after the first incidence.
Results
12,349 patients (14.6%) experienced a contralateral hip fracture within five years. The strength of association were: female gender (Odds Ratio 1.58), alcohol abuse 1.57, living in a single household 1.10, no prescription of bisphosphonates 1.64, and comorbidity and Charlson Score values less than 2 2.20, between 3 and 4 1.76, 5 and more, 1.46 against no comorbidity. The probability of experiencing a second fracture ranged from 3.4% to 25.9%.
Discussion
Once this instrument is validated in other cohorts it provides a rational basis for prophylactic augmentation or more aggressive pharmaceutical treatment.
