Abstract 15170: Telomere Length and Incident Carotid Atherosclerosis
Background: Telomere length shortens progressively during each round of cell division and declines significantly with age, and thus has emerged as a valuable biomarker for cellular aging and age-related disorders including atherosclerosis. Though cross-sectional association of shorter leukocyte telomere length (LTL) with atherosclerosis has been consistently reported, a causal link between telomere shortening and risk of carotid atherosclerosis has not been well-established.
Objective: To examine whether baseline LTL predicts incident carotid plaque after an average of 5.5 years of follow-up in American Indians participating in the Strong Heart Family Study (SHFS).
Method: A total of 3,665 American Indians (14 - 93 years old) residing in Arizona, North/South Dakota and Oklahoma enrolled in the SHFS in 2001-2003 were followed through the end of 2009. Carotid atherosclerosis was assessed by ultrasound. The presence of discrete atherosclerotic plaque was defined as focal protrusion with an arterial wall thickness exceeding that of the surrounding wall by 50%. LTL was measured by quantitative PCR in DNA collected in 2001-2003. The prospective association between baseline LTL and the time to the development of carotid plaque was examined using multivariate survival analysis, adjusting for age at baseline, sex, center, body mass index, smoking, alcohol drinking, total cholesterol, high-density lipoprotein cholesterol, estimated glomerular filtration rate (eGFR), and history of hypertension or diabetes. Family relatedness was controlled by the shared frailty model implemented in SAS.
Results: Among 2,091 participants free of cardiovascular disease and carotid plaque at baseline, 357 (17.1%) developed carotid plaque during an average 5.5 years of follow-up. Compared to the lowest (shortest) LTL tertile, hazard ratios (HR) for incident carotid plaque in subjects belonging to LTL tertiles 2 and 3 were 0.76 (95% CI, 0.58-0.98), and 0.65 (95% CI, 0.48-0.89), respectively, after controlling for traditional cardiovascular risk factors.
Conclusion: Shorter LTL significantly predicts incident carotid plaque independent of known coronary risk factors, suggesting that LTL could serve as a predictive marker for atherosclerosis.
- © 2013 by American Heart Association, Inc.