Diabetes Risk Factors and Bone Microarchitecture as Assessed by High-Resolution Peripheral Quantitative Computed Tomography (HR-pQCT) in Adults with Long-standing Type 1 Diabetes
Objective: To determine whether type 1 diabetes and its complications are associated with bone geometry and microarchitecture.
Research Design and Methods: Cross-sectional study embedded in a long-term observational study. High-resolution peripheral quantitative computed tomography (HR-pQCT) scans of distal radius and distal and diaphyseal tibia were performed in a subset of 183 type 1 diabetes participants from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) and 94 controls without diabetes. HbA1c, skin advanced glycation end products (AGEs), and diabetes-related complications were assessed in EDIC participants with >30 years of follow-up.
Results: Compared to controls (60±8 years-old, 65% female), EDIC participants (60±7 years-old, diabetes duration 38±5 years, 51% female) had lower total bone mineral density (BMD) at distal radius (-7.9%, 95%CI:(-15.2%,-0.6%), p=0.030) and distal tibia (-11.3%, 95%CI:(-18.5%,-4.2%), p=0.001); larger total area at all sites (distal radius +4.7%, 95%CI:(+0.5%,+8.8%), p=0.030; distal tibia +5.9%, 95%CI:(+2.1%,+9.8%), p=0.003; diaphyseal tibia +3.4%, 95%CI (+0.8%,+6.1%), p=0.011); and poorer radius trabecular and cortical microarchitecture. Estimated failure load was similar between two groups. Among EDIC, higher HbA1c, AGE and macroalbuminuria were associated with lower total BMD. Macroalbuminuria was associated with larger total area and lower cortical thickness at distal radius. Higher HbA1c and AGE, lower glomerular filtration rate, peripheral neuropathy and retinopathy were associated with deficits in trabecular microarchitecture.
Conclusions: Type 1 diabetes is associated with lower BMD, larger bone area and poorer trabecular microarchitecture. Among 1 diabetes, suboptimal glycemic control, AGE accumulation and microvascular complications are associated with deficits in bone microarchitecture and lower BMD.