Is there an association between tendinopathy and diabetes mellitus? A systematic review with meta-analysis.

BACKGROUND: Musculoskeletal symptoms limit adherence to exercise interventions for individuals with type 2 diabetes. People with diabetes may be susceptible to tendinopathy due to chronically elevated blood glucose levels. Therefore, we aimed to investigate this potential association by systematically reviewing and meta-analysing case-control, cross-sectional, and studies that considered both of these conditions. METHODS: Nine medical databases and hand searching methods were used without year limits to identify all relevant English language articles that considered diabetes and tendinopathy. Two authors applied exclusion criteria and one author extracted data with verification by a second author. Meta-analysis was conducted using a random effects model. Results were expressed as odds ratio (OR), mean difference or standardised mean difference with a confidence intervals (95% CI). Heterogeneity was assessed by I(2). FINDINGS: 31 studies were included in the final analysis of which 26 recruited people with diabetes and five recruited people with tendinopathy. Tendinopathy was more prevalent in people with diabetes (17 studies, OR 3·67, 95% CI 2·71 to 4·97), diabetes was more prevalent in people with tendinopathy (5 studies, OR 1·28, 95% CI 1·10 to 1·49), people with diabetes and tendinopathy had a longer duration of diabetes than people with diabetes only (6 studies, mean difference 5·26 years, 95% CI 4·15 to 6·36) and people with diabetes had thicker tendons than controls (9 studies, standardised mean difference 0·79 95% CI 0·47 to 1·12). INTERPRETATION: These findings provide strong evidence that diabetes is associated with higher risk of tendinopathy. This is clinically relevant as tendinopathy may affect adherence to exercise interventions for diabetes.

Does type 1 diabetes mellitus affect Achilles tendon response to a 10 km run? A case control study.

BACKGROUND: Achilles tendon structure deteriorates 2-days after maximal loading in elite athletes. The load-response behaviour of tendons may be altered in type 1 diabetes mellitus (T1DM) as hyperglycaemia accelerates collagen cross-linking. This study compared Achilles tendon load-response in participants with T1DM and controls. METHODS: Achilles tendon structure was quantified at day-0, day-2 and day-4 after a 10 km run. Ultrasound tissue characterisation (UTC) measures tendon structural integrity by classifying pixels as echo-type I, II, III or IV. Echo-type I has the most aligned collagen fibrils and IV has the least. RESULTS: Participants were 7 individuals with T1DM and 10 controls. All regularly ran distances greater than 5 km and VISA-A scores indicated good tendon function (T1DM = 94 ± 11, control = 94 ± 10). There were no diabetic complications and HbA1c was 8.7 ± 2.6 mmol/mol for T1DM and 5.3 ± 0.4 mmol/mol for control groups. Baseline tendon structure was similar in T1DM and control groups - UTC echo-types (I-IV) and anterior-posterior thickness were all p > 0.05. No response to load was seen in either T1DM or control group over the 4-days post exercise. CONCLUSION: Active individuals with T1DM do not have a heightened Achilles tendon response to load, which suggests no increased risk of tendon injury. We cannot extrapolate these findings to sedentary individuals with T1DM.