Leukocyte telomere length and mortality in the Cardiovascular Health Study

J Gerontol A Biol Sci Med Sci. 2011 Apr;66(4):421-9. doi: 10.1093/gerona/glq224. Epub 2011 Feb 2.

Abstract

Background: Leukocyte telomere length (LTL) is related to diseases of aging, but studies of mortality have been inconsistent.

Methods: We evaluated LTL in relation to total mortality and specific cause of death in 1,136 participants of the Cardiovascular Health Study who provided blood samples in 1992-1993 and survived through 1997-1998. LTL was measured by Southern blots of the terminal restriction fragments. Cause of death was classified by a committee of physicians reviewing death certificates, medical records, and informant interviews.

Results: A total of 468 (41.2%) deaths occurred over 6.1 years of follow-up in participants with mean age of 73.9 years (SD 4.7), 65.4% female, and 14.8% African American. Although increased age and male gender were associated with shorter LTLs, African Americans had significantly longer LTLs independent of age and sex (p < .001). Adjusted for age, sex, and race, persons with the shortest quartile of LTL were 60% more likely to die during follow-up than those within the longest quartile (hazard ratio: 1.61, 95% confidence interval: 1.22-2.12, p = .001). The association remained after adjustment for cardiovascular disease risk factors. Evaluations of cause of death found LTL to be related to deaths due to an infectious disease etiology (hazard ratio: 2.80, 95% confidence interval: 1.32-5.94, p = .007), whereas a borderline association was found for cardiac deaths (hazard ratio: 1.82, 95% confidence interval: 0.95-3.49, p = .07) in adjusted models. Risk estimates for deaths due to cancer, dementia, and ischemic stroke were not significant.

Conclusion: These data weakly corroborate prior findings of associations between LTL and mortality in the elderly.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aging / genetics*
  • Body Mass Index
  • Cardiovascular Diseases / mortality*
  • Cause of Death*
  • Comorbidity
  • Coronary Disease / mortality
  • Diabetes Mellitus / epidemiology
  • Female
  • Humans
  • Hypertension / epidemiology
  • Leukocytes / metabolism
  • Longitudinal Studies
  • Male
  • Prospective Studies
  • Smoking / epidemiology
  • Stroke / mortality
  • Telomere / genetics*