For children with type 1 diabetes (T1D), adverse effects on bone mineral density (BMD) begin early in the course of disease, according to study results published in The Journal of Clinical Endocrinology & Metabolism.
The results also indicated that poor glycemic control is associated with lower bone accrual.
The study included children age 7 to 17 years who were enrolled within 30 days of diagnosis of T1D (n = 36). The researchers obtained whole-body and regional dual-energy x-ray absorptiometry scans and tibia peripheral quantitative computed tomography at baseline and after 12 months of follow-up. The primary outcome was bone accrual assessed by bone mineral content (BMC) and areal BMD velocity z score. Sex- and age-specific reference data were retrieved from contemporary National Health and Nutrition Evaluation Surveys.
Compared with reference data, measures from participants with T1D showed lower total body less head BMC (z score, -0.46 ± 0.76), femoral neck areal BMD (z score, -0.57 ± 0.99), and tibia cortical volumetric BMD (z score, -0.44 ± 1.11) at baseline (P <.05 for all).
After 12 months, accrual of total body less head BMC was lower among participants with poor glycemic control (hemoglobin A1c [HbA1c] ≥7.5%) compared with patients with good glycemic control (HbA1c <7.5%; z score, -0.36 ± 0.84 vs 0.58 ± 0.71; P =.003).
The results indicated that total body less head BMC velocity was correlated with gains in tibia cortical area (R, 0.71; P =.003) and periosteal circumference z scores (R, 0.67; P =.007) in participants with good glycemic control. These correlations were not present in participants with poor glycemic control.
“Further longitudinal studies of longer duration are needed to determine if early and sustained reductions in HbA1c are necessary and/or sufficient to normalize bone accrual and reduce fracture risk in patients with T1D,” the researchers wrote.
Weber DR, Gordon RJ, Kelley JC, et al. Poor glycemic control is associated with impaired bone accrual in the year following a diagnosis of type 1 diabetes [published online April 29, 2019]. J Clin Endocrinol Metab. doi:10.1210/jc.2019-00035