Telomere length is associated with increased risk of cardiovascular events in patients with end-stage kidney disease on hemodialysis.

INTRODUCTION Patients with chronic kidney disease (CKD), especially those with end-stage kidney disease (ESKD) on hemodialysis (HD), are at increased risk for cardiovascular disease (CVD), including myocardial infarction and ischemic stroke. A shortening in telomere length, as a parameter for accelerated vascular aging, is an established biomarker for CVD in the general population. We aimed to elucidate the role of telomere length in ESKD patient on HD and its association with cardiovascular outcomes. METHODS Telomere length was measured in a prospective population-based cohort study of prevalent HD patients. DNA was isolated from whole blood, sampled at baseline, and analyzed for telomere length via a qPCR-based approach. The risk for the occurrence of the independently adjudicated 3P-MACE outcome (myocardial infarction, ischemic stroke, and cardiovascular death) was statistically analyzed considering the competing risk of non-cardiovascular death. RESULTS In the cohort of 308 patients with ESKD (115 (37.3%) women, median (25th-75th percentile) age: 67.0 (56.8 - 76.0), the median telomere length was 1.51 kb (25th-75th percentile 0.6-3.2 kb). The 3P-MACE outcome occurred with an incidence rate of 9.4 per 100 patient-years. Patients with longer telomere length more frequently had vascular nephropathy compared to patients with shorter telomere length. Interestingly, patients in the highest quartile of telomere length had a 1.8-fold increased risk for 3P-MACE (95%CI 1.051-3.201, p=0.033), after multivariable adjustment for age, history of stroke, myocardial infarction, venous thromboembolism, presence of heart valve replacement, atrial fibrillation, smoking, anticoagulation, or immunosuppressive use. CONCLUSION Surprisingly, in this high-risk cohort of patients with ESKD on HD, longer telomere lengths were associated with increased risk of cardiovascular events.