Ankle fractures do not predict osteoporotic fractures in women with or without diabetes

Summary It is not clear whether ankle fractures predict future osteoporotic fractures in women, and whether diabetes influences this relationship. We found that a prior ankle fracture does not predict subsequent osteoporotic fractures in women with or without diabetes. Introduction We aimed to determine: (1) whether a prior ankle fracture was a risk factor for a subsequent major osteoporotic fracture in older women; (2) whether this risk was modified by the presence of diabetes; (3) the risk factors for ankle fracture in older women. Methods We identified 3,054 women age 50 years and older with diabetes and 9,151 matched controls using the Manitoba Bone Density Program database. Multivariable regression models were used to examine factors associated with prior ankle fracture, and the importance of prior ankle fracture as a predictor of subsequent major osteoporotic fracture during a mean 4.8 years of observation. Results A prior ankle fracture was not a significant predictor of subsequent major osteoporotic fracture for women with diabetes (hazard ratio [HR] 1.13; 95% confidence interval [CI], 0.68–1.83; p=0.623) or women without diabetes (HR 1.16; 95% CI, 0.79–1.71; p=0.460), and there was no interaction between diabetes and ankle fracture after pooling all women in the cohort (p=0.971). The presence of diabetes was not independently associated with prior ankle fracture (adjusted odds ratio [OR] 1.14 [95% CI, 0.93–1.38], p=0.200), whereas higher body mass index (adjusted OR 1.04 per standard deviation increase [95% CI, 1.03–1.06], p<0.001), previous major osteoporotic fracture (adjusted OR 1.40 [95% CI, 1.13–1.75], p= 0.002), and multiple comorbidities (>6 ambulatory diagnostic groups) (adjusted OR 1.81 [95% CI, 1.40–2.36], p< 0.001) were related to prior ankle fracture. Conclusions Ankle fracture was not a significant predictor of major osteoporotic fracture in women, and a diagnosis of diabetes did not influence the relationship.