title: Leukocyte telomere length and mortality among U.S. adults: Effect modification by physical activity behaviour.
abstract: The purpose of this study was to examine the association between leukocyte telomere length (LTL) and mortality (outcome variable), with consideration by physical activity behaviour. Data from the 1999-2002 National Health and Nutrition Examination Survey were employed (N = 6,611; 20-85 yrs), with follow-up mortality assessment through 31 December 2006. DNA was extracted from whole blood to assess LTL via quantitative polymerase chain reaction. Compared to those in the first LTL tertile, the adjusted hazard ratio for all-cause mortality for those in the 2ndand 3rdLTL tertiles, respectively, was 0.82 (95% CI: 0.60-1.12; P = .22) and 0.76 (95% CI: 0.50-1.14; P = .18). However, after adjustments, LTL tertile 3 (vs. 1) was associated with all-cause mortality (HR = 0.37; 95% CI: 0.14-0.93; P = .03) for those who engaged in moderate-intensity exercise. Similarly, LTL was associated with CVD-specific mortality for those who engaged in moderate-intensity exercise (HR = 0.17; 95% CI: 0.04-0.73; P = .02). Longer telomeres are associated with increased survival, particularly among men and those who are active, underscoring the importance of promotion of physical activity behaviour.
authors.affiliation: a Physical Activity Epidemiology Laboratory, Exercise Psychology Laboratory, Department of Health, Exercise Science and Recreation Management , The University of Mississippi , University , MS , USA.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Loprinzi
authors.affiliation: b Kevser Ermin Applied Physiology Laboratory, Department of Health, Exercise Science, and Recreation Management , The University of Mississippi , University , MS , USA.
authors.forename: Jeremy P
authors.initials: JP
authors.lastname: Loenneke
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D002318:Cardiovascular Diseases / Q000401:mortality; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009749:Nutrition Surveys; D059505:Telomere Homeostasis; D014481:United States / Q000453:epidemiology; D055815:Young Adult
keywords: Aging; apoptosis; epidemiology; exercise; genomic integrity; survival