Objectives: Bone health is affected in Type-1-Diabetis (T1D) causing higher risk of hip fractures, prolonged fracture healing and altered bone mineral density (BMD). In T1D adults BMD is found to be decreased. In this study we have measured the BMD in children and adolescents from the Copenhagen Pediatric T1D Cohort.
Methods: 276 children and adolescents (131 girls) were included from the diabetes outpatient clinic at Herlev University Hospital. All patients underwent a physical examination, had blood tests drawn, and BMD Z-scores assessed by Dual Energy X-ray Absorptiometry (DXA). Standard deviation scores (SDS) on height, weight and BMI were used from a Danish study of more than 12.000 healthy children and adolescents. Glycemic control was evaluated by HbA1c (mmol/mol). T-tests were used to test for differences between gender, and linear regression analyses were used to estimate factors influencing the BMD.
Results: Mean age of participants was 13.6 (±3.7) and mean diabetes duration was 4.9 (±3.5) years. Mean HbA1c was 62.6 (±14.3). Mean total daily insulin dose was 0.85 IE/kg (±0.29) and 175 (63.4) % were treated with continuous subcutaneous insulin infusion. T1D patients had significantly higher weight and BMI SDS compared to the background population (+0.34 and +0.39 respectively) and had a higher BMD Z-score (+0.74). Separated into sex, only girls remained heavier and with a higher BMI compared to the background population and girls had a higher HbA1c compared to boys (64.8 vs 60.6). Both genders had higher BMD Z-score (+0.64 and +0.85). When comparing patients with optimal HbA1c (<=58) with poorly controlled (HbA1c >=75) we found no difference in weight or BMI, but a significantly lower BMD Z-score in the poorly controlled (P=0.02). Both groups did however have higher BMD Z-score compared to the background population. Linear regression analysis demonstrated significant negative effect of HbA1c and positive influence of BMI on BMD Z-score.
Conclusion: Our study reveals that children and adolescents with T1D have a higher BMD compared to the general population. Though a higher HbA1c correlates to lower BMD the increased BMI found in girls with T1D may in part explain the overall increase, however BMI in boys were equal to the background population and they still had higher BMD. Further research is needed to fully elucidate the relationship between BMD and diabetes in children and adolescents.
27 - 29 Sep 2018
European Society for Paediatric Endocrinology