Association of Telomere Length With Myocardial Infarction: A Prospective Cohort From the Population Based HUNT 2 Study

As possible markers of biological age, telomere length (TL) has been associated with age-related diseases such as myocardial infarction (MI) with conflicting findings. We sought to assess the relationship between TL and risk of future MI in 915 healthy participants (51.7% women) 65 years or older from a population-based prospective cohort (the HUNT 2 study, Norway). Mean TL was measured by quantitative PCR expressed as relative T (telomere repeat copy number) to S (single copy gene number) ratio, and log-transformed. During a mean follow up of 13.0 (SD, 3.2) years and 11,923 person–years, 82 participants were diagnosed with MI. We used Cox proportional hazard regressions to estimate hazard ratios (HR) and 95% confidence interval (CI). Relative TL was associated with age in women (P=0.01), but not in men (P=0.43). Using relative TL as a continuous variable, we observed a higher risk of MI in participants with longer telomeres with HRs of 2.46 (95% CI; 1.13 to 4.54) in men, and 2.93 (95% CI; 1.41 to 6.10) in women. Each 1-SD change in relative TL was associated with an HR of 1.54 (95% CI; 1.15 to 2.06) and 1.67 (95% CI; 1.18 to 2.37) in men and women, respectively. Compared with the bottom tertile of relative TL, HR of incident MI in top tertile was 2.71 (95% CI; 1.25 to 5.89) in men, and 3.65 (95% CI; 1.35 to 9.90) in women. Longer telomeres in healthy participants 65 years or older are associated with a high risk of incident MI. Future large scale prospective studies are needed to confirm these findings and explore the potential association between TL and MI.