Assessing the Relationship Between Telomere Length and Adipose Tissue Distribution

BACKGROUND: A telomere is a region of repetitive nucleotide sequences at each end of a chromosome, which protects the end of the chromosome from deterioration. Telomere shortening, a surrogate marker of cellular aging, may accelerate from the inflammatory stressors of obesity. The association between adipose tissue depots and telomere length is unknown. METHODS: Data were analyzed from 2,551 participants in the Dallas Heart Study, a prospective multiethnic cohort. The sample composition was 41% male, 59% female, 48% African American, 35% Caucasian, 15% Hispanic and participants had a mean age of 51 years with 23.4% >60 years of age. Leukocyte telomere length (LTL) was determined using qPCR on DNA isolated from circulating leukocytes. Visceral (VAT) and subcutaneous (SAT) abdominal fat masses were measured by MRI, lower body fat (LBF) by dual x-ray absorptiometry, and liver fat by MR spectroscopy. Linear regression was used to evaluate the association between LTL and body fat depots. RESULTS: In univariate analysis, shorter LTL was associated with higher VAT (p=.0002) and less LBF (p=.02). Shorter telomeres were also associated with older age, male sex, hypertension, diabetes, smoking, decreased kidney function and decreased physical activity (p<0.05 for all). Adjustment for age and sex attenuated the relationships between LTL and VAT, SAT, LBF, and liver fat. No significant interactions were seen by stratification within age groups or by severity of obesity. Variable Beta unadjusted p unadjusted Beta adjusted p adjusted VAT -0.072 0.0002* 0.009 0.6 SAT 0.021 0.29 0.016 0.38 Lower Fat 0.048 0.02* 0.024 0.19 Liver Fat 0.03 0.41 0.032 0.4 Adjustments for age and sex and * p<0.05 Standardized β coefficients = estimated unit change in 1-SD of the log-transformed variable for a 1-SD increase in the telomere parameter CONCLUSIONS: While LTL is associated with pathogenic patterns of adipose tissue, this association is confounded by the close relationship between LTL and temporal aging. These findings suggest that cellular aging is not independently linked to variation in adipose tissue distribution patterns.