Among older adults without diabetes, a relationship between increasing insulin resistance and lower risk for fracture is mediated by BMI and bone mineral density, suggesting that the association is explained by higher BMI and BMD levels often seen in insulin resistance, according to an analysis of data from the Health ABC study.

“It is not clear whether the net effect of [insulin resistance] is favorable or unfavorable for the risk of fractures,” Nicola Napoli, MD, PhD, of the division of endocrinology and diabetes at the University Campus Bio-Medico di Roma in Rome, and colleagues wrote in the study background. “It is possible that, being positively associated with BMD, [insulin resistance] reduces fracture risk. On the other hand, [type 2 diabetes] is associated with higher fracture risk in spite of higher BMD, and [insulin resistance] may have a similar relationship to fracture.”