ESPE Yearbook of Paediatric Endocrinology

Diabetes Care 2021;44:1898-1905. https://pubmed.ncbi.nlm.nih.gov/34285100/

Brief Summary: This systematic review and meta-analysis of 46 studies and 6,468 participants (aged <20 years) provides evidence that youth with type 1 diabetes (T1D) have reduced lower body mineral density (BMD), as assessed by multiple modalities: DXA, peripheral quantitative computed tomography (pQCT), and/or quantitative ultrasound (QUS).

Assessing bone health in people with T1D is important based on adult studies suggesting an increased fracture risk compared to the general population, due to reduced BMD and poor bone quality (1). Data in children and adolescents with T1D are less clear and consequently, although bone health is considered as one of the comorbidities of T1D in international guidelines, there are no clear recommendations on screening.

This meta-analysis, although limited by heterogeneity between the included studies and the assessment of BMD by pQCT or QUS in only few studies, is the first to examine multiple modalities to assess BMD. DXA is the classical method used for BMD although it can be limited by its dependency on body size and lack of reporting z-scores in several studies. QUS and pQCT, which are primarily used in the research settings, may be more appropriate for assessing a maturing skeleton, being less influenced by bone size and use less radiation (2).

Youth with T1D had lower total body, spine, and femoral neck BMD, as well as lower total body BMD and lumbar spine BMD z scores (by DXA) and lower phalangeal and calcaneal BMD (QUS). pQCT demonstrated a differential effect of T1D on the trabecula and cortical components of bone. The only factor associated to BMD was age. However, there was high heterogeneity across studies in reporting other variables which could have affected the results.

It is surprising that HbA1c was not associated to BMD, and this can be explained by inclusion of only cross-sectional HbA1c values, therefore limiting the assessment of longterm glycemic control. Chronic hyperglycemia was previously hypothesized to induce altered osteoblast differentiation and maturation and alteration of osteoclast activity (3). Overall, these findings suggest that routine assessment of BMD should be considered in youth with T1D, although further data are needed to support that. Similarly, there is a need to understand the mechanisms of abnormal bone development in T1D to inform recommendations for prevention.

References: 1. Shah VN, Shah CS, Snell-Bergeon JK. Type 1 diabetes and risk of fracture: meta-analysis and review of the literature. Diabet Med 2015;32:1134–1142. 2. Chobot AP, Haffke A, Polanska J, et al. Bone status in adolescents with type 1 diabetes. Diabetologia 2010;53:1754–1760. 3. Valerio G, del Puente A, Esposito-del Puente A, Buono P, Mozzillo E, Franzese A. The lumbar bone mineral density is affected by long-term poor metabolic control in adolescents with type 1 diabetes mellitus. Horm Res 2002; 58: 266–272.