Risk of short telomere as biomarker of diabetes mellitus type 2 status in the CORDIOPREV study

The presence of type 2 diabetes mellitus (T2DM) in cardiovascular disease (CVD) is associated with poorer clinical outcomes. To identify biomarkers is essential to predict T2DM onset and progression in the context of secondary prevention. Telomere length (TL), a marker of cellular aging, has been linked to oxidative stress, inflammation, and metabolic dysfunction, including diabetes-related complications. This study aims to evaluate TL as a potential biomarker for T2DM in patients with coronary heart disease (CHD).

We included 956 patients from the CORDIOPREV study with available TL data. Participants were classified according to their diabetes status at the end of the dietary intervention: 407 were free of T2DM and 549 were classified as having T2DM. TL was measured by quantitative PCR. Patients with TL values below the 20th percentile of the study population were categorized as having short telomeres.

TL was significantly shorter in T2DM patients compared to non-T2DM (1.26±0.74 vs. 1.38±0.84; p=0.026). Each 1-SD increase in TL was associated with a 17% lower risk of T2DM (OR 0.83, 95% CI 0.69-0.98). Patients at risk of short TL (<20th percentile) showed a higher prevalence of T2DM (20% vs. 17%; p=0.035) and a 42% increased risk of its presence (OR 1.42, 95% CI 0.99-2.02). In stepwise regression models, TL, age, BMI, insulin, triglycerides, and HbA1c emerged as independent predictors of T2DM. After adjusting for fasting glucose, TL lost significance as a continuous variable, but short TL risk remained independently associated with T2DM (OR 1.57, p=0.049).

Shorter TL is associated with the presence of T2DM in patients with CHD, supporting its potential role as an independent biomarker for T2DM risk in secondary prevention.