Serum Insulin-Like Growth Factor-I Concentration Is Associated with Leukocyte Telomere Length in a Population-Based Cohort of Elderly Men.
Context: Both leukocyte telomere length and IGF-I are associated with the aging process. A previous in vitro study suggested that IGF-I may modulate telomerase activity in white blood cells, but little is known whether these two systems interact in vivo. Patients and Methods: Leukocyte telomere length was determined using a quantitative PCR assay in 2744 elderly men (mean age 75.5 yr, range 69-81