Risk factors for ankle fractures in older adults based on clinical components of the Fracture Risk Assessment (FRAX) tool and comorbidities in Korea: a retrospective case-control study

Background: Ankle fractures are common in older adults; however, their relationship with osteoporotic fractures remains unclear. This study aimed to evaluate potential risk factors for ankle fractures in older adults by analyzing individual clinical components of the Fracture Risk Assessment (FRAX) tool and comorbidities. Methods: We conducted a retrospective case-control study including 84 patients aged ≥65 years with ankle fractures and 150 controls who underwent bone mineral density (BMD) testing without prior ankle fractures. The variables analyzed included age, sex, body mass index, smoking, alcohol consumption, prior fracture history, and comorbidities such as hypertension, diabetes mellitus, and dementia. BMD was measured at the spine, total hip, and femoral neck. Results: Univariate analysis showed that alcohol consumption, diabetes mellitus, and total hip T-score categories were significantly associated with ankle fractures. In binary logistic regression, alcohol consumption remained significantly associated with higher ankle fracture risk (odds ratio [OR], 5.302; 95% confidence interval [CI], 1.778–15.811; P=0.003), and both osteopenia and osteoporosis at the total hip were also associated with increased risk (OR, 3.260, P=0.049; OR, 3.561, P=0.031, respectively). Diabetes mellitus did not reach statistical significance in the adjusted model (P=0.074). Model fit was adequate (Hosmer-Lemeshow P=0.377), and post hoc power analysis confirmed sufficient sample size. Conclusions: These findings suggest that lower total hip BMD and alcohol-related factors may be associated with ankle fracture risk in older adults. The FRAX score itself was not calculated; instead, this study focused on analyzing selected clinical components. Limitations include the retrospective design, lack of fall and medication data, and cross-sectional BMD assessment.Level of evidence: III.