Fracture risk assessment (FRAX) without BMD and risk of major osteoporotic fractures in adults with type 1 diabetes

Abstract

Objective: To evaluate the association between Fracture Risk Assessment Tool (FRAX) without bone mineral density (BMD) and risk for major osteoporotic fractures (MOF) in type 1 diabetes.

Methods: Subjects with type 1 diabetes and without diabetes from the 'Coronary Artery Calcification in Type 1 Diabetes' study were included. Risk for MOF was calculated using FRAX-based clinical risk factors and without BMD at visit 3 (2006-2008). Incident fractures were defined as fractures that occurred between visit 3 and visit 4 (2013-2017). Survival models were used to study the predictability of new MOF by diabetes status.

Results: 346 type 1 diabetes (mean age 43.3 ± 9, BMI 26.4 ± 5, diabetes duration 29.4 ± 8.6 years, A1c 7.8 ± 1.1) and 411 controls (mean age 46.9 ± 9 years, BMI 26.3 ± 5 kg/m², A1c 5.5 ± 0.4) were analyzed in this study. In unadjusted survival analysis, the FRAX score without BMD was significantly associated with MOF (HR 1.08, 95% CI: 1.04-1.13, p < 0.0001), and remained significantly associated after adjustment for age and sex (HR 1.09, 95% CI: 1.04-1.15, p = 0.0007) and type 1 diabetes (HR 1.08, 95% CI: 1.04-1.12, p = 0.0002). In the fully adjusted model (adjusted for age, sex and type 1 diabetes), the FRAX score without BMD was the only variable significantly associated with risk of MOF (HR 1.08, 95% CI: 1.02-1.14, p = 0.006).

Conclusion: Clinical use of FRAX without BMD is useful tool in identifying adults with type 1 diabetes at higher risk for MOF risk and may help clinicians to guide therapeutic decision-making in this high fracture risk population.

Keywords: Bone mineral density; FRAX; Fracture risk; Fracture risk assessment tool; Major osteoporotic fracture; Type 1 diabetes.