Background/Aims Telomere shortening is a biomarker of aging, but it is still unclear whether it directly influences aging-related health changes and mortality, or largely reflects the accumulating influences of environmental influences and declining health. Prior studies have reported associations between short telomeres and many health conditions. Mendelian syndromes and heritability studies demonstrate the biological underpinnings of telomere length (TL), yet other studies show that environmental and behavioral factors also influence telomere lengths.

Methods As part of the RPGEH, the Genetic Epidemiology Research Study on Adult Health and Aging (GERA), a multi-ethnic cohort (average age = 63 years) has measured TL from saliva samples on over 100,000 individuals with linked electronic medical records. A survey of demographic and behavioral factors was conducted 2 years prior to saliva collection. With these data, we examined demographic relationships with TL, behavioral influences, and relationship of TL with all-cause mortality following sample collection.

Results As expected, TL is inversely correlated with age, and women have longer telomeres than men except as young adults. All analyses controlled for age and gender. As seen in other studies, we find significantly longer TL among African Americans than other groups. TL is positively correlated with education and body mass index (BMI), and negatively correlated with cigarette smoking and alcohol consumption. We found no relationship with major depression or stress-related disorders, even when limited to recent episodes. We found that short TL was prospectively associated with mortality, although only those with the shortest TL were at increased risk; the association suggested a critical threshold of short TL determines effects on mortality. The association persisted even after adjustment of the demographic and behavioral factors such as age, sex, race, education, BMI, smoking, and alcohol consumption.

Conclusions While this could indicate a direct effect of TL on health, it will also be important to examine the extent of pre-existing morbidities in these individuals to understand their possible role in the pathway between TL and longevity.