Abstract 5001: Longer Adulthood Leukocyte Telomere Length Is Associated with Higher High-Density Lipoprotein Cholesterol Levels Measured from Childhood to Adulthood: The Bogalusa Heart Study
Introduction - High-Density Lipoprotein Cholesterol (HDL-C) is associated with cardiovascular disease and human longevity. This study assessed the hypothesis that HDL-C levels have an impact on leukocyte telomere length (LTL, an indicator of human biological aging) and telomere shortening.
Methods - The longitudinal study cohort consisted of 462 Whites and 186 African Americans enrolled in the Bogalusa Heart Study. Study subjects were examined serially 3–12 times for HDL-C over an average of 26 years from childhood (mean age=10.2 years, range=4–17 years) to adulthood (mean age=36.1 years, range=18 – 43 years), with 3,893 serial observations. Telomere length was measured twice during adulthood at baseline (mean age=31.5 years, range=20 – 43 years) and follow-up (mean age=37.7 years, range=26 – 48 years). Growth curves of HDL-C with age were calculated; the area under the curve (AUC) was used as a measure of long-term levels from childhood to adulthood.
Results - African Americans had higher HDL-C levels in childhood and adulthood and AUC values than whites (p<0.001). African Americans also displayed longer LTLs than whites at both baseline (7835 vs 7297 bp, p<0.0001) and follow-up (7587 vs 7087 bp, p<0.0001), and a faster yearly rate of shortening in LTL (42.1 vs 34.1 bp, p=0.030). Multivariate regression analyses, using LTL measured at follow-up in adulthood as a dependent variable, showed that LTL was positively associated with HDL-C in childhood (regression coefficient (bp per mg/dL) β=2.7, p=0.043), adulthood (β=4.5, p=0.065) and AUC (β=11.2, p=0.0007) in the combined sample of African Americans and whites, adjusting for race, sex, age, body mass index and current smoking status. The association between adulthood LTL and HDL-C AUC was stronger in African Americans (β=18.3, p=0.0007) than in whites (β=6.3, p=0.137). Further, a slower rate of LTL shortening per year was significantly associated with higher HDL-C AUC in the total sample (p=0.033), adjusting for baseline LTL and the above covariates. Both African Americans and whites showed a similar but nonsignificant trend.
Conclusions - These findings reaffirm the racial difference in LTL dynamics and their associations with risk factors for atherosclerosis.
This research has received full or partial funding support from the American Heart Association, AHA National Center.