Telomere Length in Human Peripheral Blood Lymphocytes as a Biomarker of Biological Aging: A Cross-Sectional Study Across Seven Age Decades

Research on telomere length dynamics as a biological aging biomarker in peripheral blood lymphocytes represents a priority area within molecular gerontology and cellular senescence research, with direct implications for clinical biomarker development for biological aging assessment and longevity medicine. This study applies quantitative real-time PCR telomere length assay (T/S ratio method) with multivariate regression analysis to characterize progressive telomere shortening with cumulative cellular division and oxidative stress in 350 community-dwelling volunteers spanning age decades from 20 to 80 years obtained from community health clinics in the greater Seattle metropolitan area. Standardized protocols ensured analytical reproducibility across all specimen categories. Results demonstrate that telomere length decreases significantly across each successive age decade, with accelerated attrition between ages 50-70 in individuals who smoke (p < 0.001), with 23.4% of specimens exhibiting the primary phenotype of interest. Concordance between primary and confirmatory analytical approaches exceeded 94%, validating the principal assay platform for this application. These findings advance the empirical foundation for molecular gerontology and cellular senescence research and carry direct implications for the design of surveillance and intervention programs targeting progressive telomere shortening with cumulative cellular division and oxidative stress within cross-sectional age cohorts stratified by smoking status, BMI, and chronic disease burden.