Endocrine Abstracts

Objectives: Fracture risk is increased in individuals with diabetes mellitus, but how this is related to bone mineral density (BMD), adiposity, inflammation, disease duration and diabetic complications is less well understood. We aimed to investigate associations between type 1 (T1DM) and type 2 (T2DM) diabetes and incident fracture in a large population study.

Methods: UK Biobank is a population study incorporating individuals aged 40–69 years recruited during 2006–2010 from across the UK. A baseline assessment included detailed review of demographics, lifestyle, medical history, anthropometry, blood sampling and in a subset, bone mineral density (BMD) assessment by quantitative ultrasonography. We used Poisson regression to calculate incidence rate ratios (IRRs) for fracture to investigate a) prospective relationships between diabetes and fracture risk (ascertained from self-report and/or hospital records, mean follow-up time 12.3 years (S.D. 1.9)) independent of traditional clinical risk factors for fracture [BMD, fat mass and inflammation (C-reactive protein)]; b) the impact of microvascular complications; c) interaction with duration of diabetes.ResultsThere were 498 949 participants (45.5% male, mean age 56.5 years). 1836 (0.4%) had T1DM and 20 551 (4.1%) had T2DM. Fracture risk in T1DM was increased, independent of BMD, fat mass and CRP, compared to no diabetes (IRR 2.75 (95%CI 2.25, 3.36)) and T2DM (IRR 1.23 (95%CI 1.12, 1.34). Associations were similar by sex. Younger age at diagnosis of T1DM conferred mildly higher fracture risk (diagnosis at 0–10 years IRR 3.10 (95%CI 1.64,5.85), 10–20 years: IRR 2.92 (95%CI 1.99,4.27), 20–30 years: IRR 2.68 (95%CI 1.93, 3.73), 30–40 years: 2.07 (95%CI 1.34,3.22)). In individuals with T1DM, the presence of any microvascular complication conferred an increased fracture risk (IRR 1.72 (95%CI 1.15, 2.57), with a dose effect by number of complications. The risk associated with neuropathy (IRR 2.62 (95%CI 1.56,4.38)) or nephropathy (IRR 2.16 (95%CI 1.24,3.77)) was greater than eye disease (1.63 (95% CI 1.08,2.45)) in T1DM, with similar findings in T2DM.

Conclusions: Fracture risk is increased in adults with T1DM, independent of BMD, adiposity and inflammation. This risk is increased further with younger age at diagnosis and microvascular complications. Advice on optimising skeletal health should be part of diabetes care.