Type 2 diabetes (T2D) is associated with significantly increased frailty compared with the general population, according to study results published in Diabetes Care. Risk for fragility fractures is increased with frailty, and diabetes may affect fracture risk more strongly in patients who are frail.
In individuals with T2D, bone mineral density and body mass index are often both increased, which should have a protective effect against most fractures. However, T2D has presented as an independent risk factor for fractures, introducing a “diabetes bone paradox” that warrants further research. For this study, investigators followed 3149 participants (mean age, 65 ± 12 years) from the prospective Canadian Multicenter Osteoporosis Study, 138 of whom had diabetes, to explore the relationship between diabetes, frailty, and incident fracture risk.
A fragility fracture included any fracture resulting from a fall of standing height or less. Time to incident nontraumatic fragility fracture was the primary outcome, with time to spine or hip fracture being the secondary outcome. A frailty index that measured 29 health-related deficits was used to quantify frailty. Analyses were performed using Cox proportional hazard models that included the use of an interaction term: the product of frailty and diabetes.
Although bone mineral density was significantly higher in patients with vs without diabetes (P <.001), those with diabetes were also significantly frailer (frailty index, 0.22 ± 0.11 vs 0.16 ± 0.10; P <.001). The frailty index score correlated with risk for incident fragility fractures, with each 0.01-point increase in frailty index associated with a hazard ratio of 1.02 and each 0.10-point increase in frailty index associated with a hazard ratio of 1.12 in the fully adjusted model (P =.018).
Limitations to this study included an observational and nonrandomized design, participant self-reporting on diabetes diagnosis, and the fact that the original study did not distinguish between type 1 diabetes and T2D, though only a very small proportion potentially had type 1 diabetes.
“The existence of the diabetes bone paradox remains an unsolved clinical issue in general practice for the management of fracture risk in type 2 diabetes. Our data suggest frailty status may aid in the understanding of the paradox and thus enhance the quality of assessment and care for diabetes,” wrote the researchers. “Particular attention should be paid to diabetes as a risk factor for fragility fractures in those who are frail.”
The Canadian Multicenter Osteoporosis Study received funding from pharmaceutical companies, and some authors report financial associations with the pharmaceutical industry. For a full list of author disclosures, please see the original reference.
Li G, Prior JC, Leslie WD, et al. Frailty and risk of fractures in patients with type 2 diabetes [published online January 28, 2019]. Diabetes Care. doi:10.2337/dc18-1965.