Bone deficits in children and youth with type 1 diabetes: A systematic review and meta-analysis

Association of daily physical activity and bone microarchitecture in young adults with type 1 diabetes - A pilot exploratory study

Purpose

Physical activity (PA) is an important determinant of skeletal health. In young adults with type 1 diabetes (T1D) fracture risk is increased, yet few studies have examined the PA and bone health relationship. Therefore, this pilot cross-sectional study characterized PA levels and their association with bone parameters measured by high resolution peripheral quantitative computed tomography (HR-pQCT) in young adults with T1D.

Methods

HR-pQCT (Xtreme CTII) was used to measure bone outcomes at the distal tibia and radius, and accelerometery (ActiGraph GT3X) recorded daily minutes of light and moderate-vigorous physical activity (MVPA). Quadratic regression analyses were conducted with a p-value ≤ 0.05 considered significant.

Results

PA data from 19 young adults (23.1 ± 1.9 years) with T1D was analyzed. Over half (63 %) of participants completed ≥150 min of MVPA per week, however, most measured activity time per day (57 %) was spent in sedentary pursuits. Significant non-linear associations were found between the duration of MVPA and several trabecular bone parameters at the tibia.

Conclusions

In young adults with T1D, MVPA may have site specific (tibia) and compartment specific (trabecular) non-linear associations with bone. Further studies should confirm these findings, which may help inform evidence-based exercise recommendations to optimize bone health in young adults with T1D.

Bone properties in persons with type 1 diabetes and healthy controls - A cross-sectional study

BACKGROUND

The risk of fractures is increased in persons with type 1 diabetes (T1D) and assessment of bone health has been included in the 2024 updated Standards of Care by The American Diabetes Association (ADA). Previous studies have found that in T1D bone metabolism, mineral content, microstructure, and strength diverge from that of persons without diabetes. However, a clear description of a T1D bone phenotype has not yet been established. We investigated bone mechanical properties and microstructure in T1D compared with healthy controls. For the potential future introduction of additional bone measures in the clinical fracture risk assessment, we aimed to assess any potential associations between various measures related to bone indices in subjects with T1D.

METHODS

We studied human bone indices in a clinical cross-sectional setup including 111 persons with early-onset T1D and 37 sex- and age-matched control persons. Participants underwent hip and spine DXA scans for bone mineral density (BMD) of the femoral neck (FN), total hip (TH), and lumbar spine (LS), and TBS evaluation, microindentation of the tibial shaft for Bone Material Strength index (BMSi), and high-resolution periphery quantitative computed tomography (HRpQCT) of the distal radius and tibia for volumetric BMD (vBMD) and structural measures of trabecular and cortical bone. Results are reported as means with (standard deviation) or (95 % confidence intervals (CI)), medians with [interquartile range], and differences are reported with (95 % CI).

RESULTS

The study included 148 persons aged 20 to 75 years with a median age of 43.2 years. The T1D group who had all been diagnosed with T1D before the age of 18 years demonstrated values of HbA1c ranging from 39 to 107 mmol/mol and a median HbA1c of 57 mmol/mol. The BMD did not differ between groups (the mean difference in FN-BMD was 0.026 g/cm2 (-0.026; 0.079), p = 0.319) and the median BMSi was comparable in the two groups (79.2 [73.6; 83.8] in the T1D group compared with 77.9 [70.5, 86.1] in the control group). Total and trabecular vBMD (Tb.vBMD), cortical thickness (Ct.Th), and trabecular thickness (Tb.Th) of both radius and tibia were lower in participants with T1D. The mean Tb.vBMD at the radius was 143.6 (38.5) mg/cm3 in the T1D group and 171.5 (37.7) mg/cm3 in the control group, p < 0.001. The mean Ct. Thd of the radius was 0.739 mm (0.172) in the T1D group and 0.813 (0.188) in the control group, p = 0.044. Crude linear regressions revealed limited agreement between BMSi and Tb.vBMD (p = 0.010, r2 = 0.040 at the radius and p = 0.008, r2 = 0.040 at the tibia and between BMSi and the estimated failure load (FL) at the tibia (p < 0.001, r2 = 0.090). There were no significant correlations between BMSi and Ct.Th. TBS correlated with Tb.vBMD at the radius (p = 0.008, r2 = 0.044) and the tibia (p = 0.001, r2 = 0.069), and with the estimated FL at the distal tibia (p = 0.038, r2 = 0.026).

CONCLUSION

In this study, we examined the bones of persons with well-controlled, early-onset T1D. Compared with sex- and age-matched healthy control persons, we found reduced total and trabecular vBMD, as well as decreased trabecular and cortical thickness. These results suggest that a debut of T1D before reaching peak bone mass negatively impacts bone microarchitecture. No differences in areal BMD or BMSi were observed. Although the variations in total hip BMD reflect some variation in the vBMD, the reduction in trabecular bone mineral density was not captured by the DXA scan. Consequently, fracture risk may be underestimated when relying on DXA, and further research into fracture risk assessment in T1D is warranted.

Bone and muscle differences in children and adolescents with type 1 diabetes: The mediating role of physical activity

Children with type 1 diabetes (T1D) experience an increased risk of fracture, which may be related to altered bone development. We aimed to assess differences in bone, muscle and physical activity (PA), and explore if better muscle and PA measures would mitigate bone differences between children and adolescents with T1D and typically developing peers (TDP). We matched 56 children and adolescents with T1D (mean age 11.9 yrs) and 56 TDP (11.5 yrs) by sex and maturity from 171 participants with T1D and 66 TDP (6-17 yrs). We assessed the distal radius and tibia with high-resolution peripheral quantitative computed tomography (HR-pQCT), and the radius and tibia shaft bone and muscle with pQCT. We also measured muscle function from force-related measures in neuromuscular performance tests (push-up, grip test, countermovement and long jump). We compared PA based on questionnaire scores and accelerometers between groups. Bone, muscle, and neuromuscular performance measures were compared using MANOVA. We used mediation to explore the role of PA and muscle in bone differences. Children and adolescents with T1D had 6-10 % lower trabecular density, bone volume fraction, thickness and number at both distal radius and tibia, and 11 % higher trabecular separation at the distal radius than TDP. They also had 3-16 % higher cortical and tissue mineral density, and cortical thickness at the distal radius, 5-7 % higher cortical density and 1-3 % higher muscle density at both shaft sites compared to TDP. PA mediated the between-group difference in trabecular number (indirect effect -0.04) at the distal radius. Children and adolescents with T1D had lower trabecular bone density and deficits in trabecular micro-architecture, but higher cortical bone density and thickness at the radius and tibia compared to TDP. They engaged in less PA but had comparable muscle measures to those of TDP. PA participation may assist in mitigating deficit in trabecular number observed in children and adolescents with T1D.

Fracture patterns and associated risk factors in pediatric and early adulthood type 1 diabetes: Findings from a nationwide retrospective cohort study

PURPOSE

People with pediatric and early adulthood type 1 diabetes (T1D) might have a higher fracture risk at several sites compared to the general population. Therefore, we assessed the hazard ratios (HR) of various fracture sites and determined the risk factors associated with fractures among people with newly diagnosed childhood and adolescence T1D.

METHODS

All people from the UK Clinical Practice Research Datalink GOLD (1987-2017), below 20 years of age with a T1D diagnosis code (n = 3100) and a new insulin prescription, were included and matched 1:1 by sex, age, and practice to a control without diabetes. Cox regression was used to estimate HRs of any, major osteoporotic fractures (MOFs) and peripheral fractures (lower-arm and lower-legs) for people with T1D compared to controls. The analyses were adjusted for sex, age, diabetic complications, medication (glucocorticoids, anti-depressants, anxiolytics, bone medication, anti-convulsive), Charlson-comorbidity-index (CCI), hypoglycemia, falls and alcohol. T1D was further stratified by diabetes duration, presence of diabetic microvascular complications (retinopathy, nephropathy, and neuropathy) and boys versus girls.

RESULTS

The crude HRs for any fracture (HR: 1.30, CI95%: 1.11-1.51), lower-arm (HR: 1.22, CI95%: 1.00-1.48), and lower-leg fractures (HR: 1.54, CI95%: 1.11-2.13) were statistically significant increase in T1D compared to controls, but the effect disappeared in the adjusted analyses. For MOFs, no significant differences were seen. Risk factors in the T1D cohort were few, but the most predominantly one was a previous fracture (any fracture: HR: 2.00, CI95%: 1.70-2.36; MOFs: HR: 1.89, CI95%: 1.44-2.48, lower- arm fractures: HR: 2.08, CI95%: 1.53-2.82 and lower-leg fractures: HR: 2.08, CI95%: 1.34-3.25). Others were a previous fall (any fracture: HR: 1.54, CI95%: 1.20-1.97), hypoglycemia (Any fracture: HR: 1.46, CI95%: 1.21-1.77 and lower-leg fractures: HR: 2.34, CI95%: 1.47-3.75), and anxiolytic medication (Any fracture: HR: 1.52, CI95%: 1.10-2.11). Whereas girls had a lower risk compared to boys (Any fracture: HR: 0.78, CI95%: 0.67-0.90 and lower-arm fractures; HR: 0.51, CI95%: 0.38-0.68). The risk of any fracture in T1D did not increase with longer diabetes duration compared to controls (0-4 years: HR: 1.20, CI95%: 1.00-1.44; 5-9 years: HR: 1.17, CI95%: 0.91-1.50; <10 years: HR: 0.83, CI95%: 0.54-1.27). Similar patterns were observed for other fracture sites. Furthermore, one complication compared to none in T1D correlated with a higher fracture risk (1 complication: HR: 1.42, CI95%: 1.04-1.95).

CONCLUSION

The overall fracture risk was not increased in pediatric and early adulthood T1D; instead, it was associated with familiar risk factors and specific diabetes-related ones.

Trabecular bone score in adults with type 1 diabetes: a meta-analysis

Type 1 diabetes mellitus (T1DM) is associated with a disproportionately high fracture rate despite a minimal decrease in bone mineral density. Though trabecular bone score (TBS), an indirect measure of bone architecture, is lower in adults with T1DM, the modest difference is unlikely to account for the large excess risk and calls for further exploration.

INTRODUCTION

Fracture rates in type 1 diabetes mellitus (T1DM) are disproportionately high compared to the modestly low bone mineral density (BMD). Distortion of bone microarchitecture compromises bone quality in T1DM and is indirectly measured by trabecular bone score (TBS). TBS could potentially be used as a screening tool for skeletal assessment; however, there are inconsistencies in the studies evaluating TBS in T1DM. We performed this meta-analysis to address this knowledge gap.

METHODS

An electronic literature search was conducted using PubMed, Scopus, and Web of Science resources (all-year time span) to identify studies relating to TBS in T1DM. Cross-sectional and retrospective studies in adults with T1DM were included. TBS and BMD data were extracted for pooled analysis. Fracture risk could not be analyzed as there were insufficient studies reporting it.

RESULT

Data from six studies were included (T1DM: n = 378 and controls: n = 286). Pooled analysis showed a significantly lower TBS [standardized mean difference (SMD) =  - 0.37, 95% CI - 0.52 to - 0.21; p < 0.00001] in T1DM compared to controls. There was no difference in the lumbar spine BMD (6 studies, SMD - 0.06, 95% CI - 0.22 to 0.09; p = 0.43) and total hip BMD (6 studies, SMD - 0.17, 95% CI - 0.35 to 0.01; p = 0.06) in the case and control groups.

CONCLUSIONS

Adults with T1DM have a lower TBS but similar total hip and lumbar spine BMD compared to controls. The risk attributable to the significant but limited difference in TBS falls short of explaining the large excess propensity to fragility fracture in adults with T1DM. Further studies on clarification of the mechanism and whether TBS is suited to screen for fracture risk in adults with T1DM are necessary.

Bone Material Properties in Bone Diseases Affecting Children

PURPOSE OF REVIEW

Metabolic and genetic bone disorders affect not only bone mass but often also the bone material, including degree of mineralization, matrix organization, and lacunar porosity. The quality of juvenile bone is moreover highly influenced by skeletal growth. This review aims to provide a compact summary of the present knowledge on the complex interplay between bone modeling and remodeling during skeletal growth and to alert the reader to the complexity of bone tissue characteristics in children with bone disorders.

RECENT FINDINGS

We describe cellular events together with the characteristics of the different tissues and organic matrix organization (cartilage, woven and lamellar bone) occurring during linear growth. Subsequently, we present typical alterations thereof in disorders leading to over-mineralized bone matrix compared to those associated with low or normal mineral content based on bone biopsy studies. Growth spurts or growth retardation might amplify or mask disease-related alterations in bone material, which makes the interpretation of bone tissue findings in children complex and challenging.

Recommendations for High-resolution Peripheral Quantitative Computed Tomography Assessment of Bone Density, Microarchitecture, and Strength in Pediatric Populations

PURPOSE OF REVIEW

The purpose of this review is to summarize current approaches and provide recommendations for imaging bone in pediatric populations using high-resolution peripheral quantitative computed tomography (HR-pQCT).

RECENT FINDINGS

Imaging the growing skeleton is challenging and HR-pQCT protocols are not standardized across centers. Adopting a single-imaging protocol for all studies is unrealistic; thus, we present three established protocols for HR-pQCT imaging in children and adolescents and share advantages and disadvantages of each. Limiting protocol variation will enhance the uniformity of results and increase our ability to compare study results between different research groups. We outline special cases along with tips and tricks for acquiring and processing scans to minimize motion artifacts and account for growing bone. The recommendations in this review are intended to help researchers perform HR-pQCT imaging in pediatric populations and extend our collective knowledge of bone structure, architecture, and strength during the growing years.