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Updated: Feb 8, 2026
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Analyzing the Effects of Stromal Cells on the Recruitment of Leukocytes from Flow
Published on: January 7, 2015
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Leukocyte Telomere Length and All-Cause Mortality: A Between-Within Twin Study With Time-Dependent Effects Using
Yiqiang Zhan1, Xing-Rong Liu1, Chandra A Reynolds2
1Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
American Journal of Epidemiology
|July 3, 2018
Summary
Shorter leukocyte telomere length (LTL) is linked to increased mortality risk, even when accounting for shared familial factors. This association weakens over time, indicating a complex relationship between LTL and longevity.
Area of Science:
- Genetics and Aging Research
- Biomarkers of Aging
- Epidemiology of Mortality
Background:
- Leukocyte telomere length (LTL) is a biomarker associated with aging and mortality.
- Previous studies may be limited by unmeasured familial confounders.
Purpose of the Study:
- To investigate the association between LTL and all-cause mortality.
- To control for familial factors using a twin study design.
- To explore time-dependent effects of LTL on mortality.
Main Methods:
- Utilized a Swedish twin registry sample (N=366).
- Assessed LTL via Southern blot.
- Employed a between-within shared frailty model for survival analysis.
- Linked mortality data through the Swedish Population Registry.
Main Results:
- Shorter LTL was significantly associated with higher all-cause mortality rates.
- Familial factors were controlled for in the analysis.
- Significant time-dependent effects were observed, with attenuated mortality risk ratios over time.
Conclusions:
- Shorter LTL is a predictor of mortality, independent of familial factors.
- The impact of LTL on mortality risk changes with age.
- This study highlights the importance of accounting for familial effects and time-dependent associations in aging research.
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