Higher Charlson Comorbidity Index is a Risk Factor for Hip Fracture in Older Adults at Lower Temperatures: A Cross-sectional Study (Preprint)

BACKGROUND The incidence of hip fractures is increasing, and there have been reports linking cold weather to a higher risk of fractures. OBJECTIVE The study aimed to evaluate clinical variables in hip fracture patients who may predispose them to such fractures under different temperatures. METHODS This is a cross-sectional study conducted at a single medical center, enrolling older adults (≥60 years) who had experienced a hip fracture. Comprehensive clinical histories and detailed information regarding each patient's hip fracture were obtained. All meteorological data were extracted from the Taiwan Central Weather Bureau database. Multiple clinical parameters that may have a close connection with the temperature at which the hip fracture occurred were screened. Statistical analysis involved using the Pearson correlation test or the independent Student’s t-test, followed by generalized estimating equation analysis. RESULTS The cohort comprised 506 older adults with hip fractures. Initial univariate analysis revealed that a history of past cerebrovascular accidents, Charlson Comorbidity Index, patient age, and preinjury Barthel Index were significantly related to the temperature at which the hip fractures occurred. The generalized estimating equation analysis indicated that only the Charlson Comorbidity Index had a considerably inverse association with temperature. This finding suggests that for older adults with a higher Charlson Comorbidity Index, hip fractures tend to occur at lower temperatures, and vice versa. CONCLUSIONS Comorbidities are the only clinical concern that predisposes older adults to hip fracture under colder temperatures. This epidemiological finding could guide future patient education and hip fracture prevention programs. CLINICALTRIAL TMU-JIRB N201709053