U-Shaped Relationship of Leukocyte Telomere Length With All-Cause and Cancer-Related Mortality in Older Men.
Level 3 - non-randomized controlled study
Prospective observational cohort study evaluating a prognostic biomarker.
PubMed 32761187 · doi:10.1093/gerona/glaa190
What was done
In a cohort of 3,608 community-dwelling men (mean age 77.0 ± 3.6 years), leukocyte telomere length (LTL) was measured using multiplex quantitative PCR (T/S ratio). Deaths from all causes, cardiovascular disease (CVD), and cancer were identified through data linkage. Associations were evaluated using restricted cubic splines and Cox proportional hazards models adjusted for age, cardiometabolic risk factors, and baseline prevalent diseases.
What was found
LTL showed a U-shaped relationship with all-cause and cancer mortality. Men in the middle quartiles of LTL had significantly lower all-cause mortality compared to the lowest quartile (Q2 vs Q1: HR = 0.86, 95% CI 0.77–0.97, p = .012; Q3 vs Q1: HR = 0.88, 95% CI 0.79–0.99, p = .032). Similarly, middle quartiles had lower cancer mortality (Q2 vs Q1: HR = 0.73, 95% CI 0.59–0.90, p = .004; Q3 vs Q1: HR = 0.75, 95% CI 0.61–0.92, p = .007). No association was observed between LTL and CVD mortality.
Why it matters
These findings challenge the assumption that longer telomeres are uniformly protective in aging, indicating that both very short and very long telomeres correlate with increased mortality risk, particularly from cancer.
Limits
The study included only older men, precluding generalization to women or younger cohorts. LTL was measured at a single time point without longitudinal tracking, and exact follow-up duration was not reported in the abstract.
Cited by
- supports Telomere length exhibits a U-shaped relationship with health risks, where having telomeres that are either excessively short or excessively long is disadvantageous.