Genetically-estimated Telomere Length Weakly Associates With Body Composition And Metabolic Profiles But Not Cardiorespiratory Fitness

Telomere length is associated with many age-related diseases. However, its association with fitness-related traits and exercise responses are less understood. PURPOSE: To investigate the association of genetically estimated telomere length (gTL) with cardiorespiratory fitness (CRF) traits and metabolic traits before and after endurance exercise training in the HERITAGE Family Study. METHODS: gTL was calculated in Black and White adults from the HERITAGE Family Study (n=708) using 9 established telomere length GWAS SNPs. Race-stratified associations between gTL and baseline measures and changes in CRF traits, body composition, and the components of metabolic syndrome were determined using partial correlations controlling for age. RESULTS: Mean (±SE) gTL significantly (p<0.001) differed between Black (754.5±8.2 bp) and White subjects (603.1±5.98 bp). There were no associations between gTL and CRF traits at baseline or in response to training in Black or White subjects. Furthermore, there were no associations between gTL and body composition traits at baseline or in response to training in Black subjects. In White subjects, gTL was negatively, weakly correlated with baseline body composition measures including: BMI (r=-0.14), waist circumference (r=-0.12), visceral fat (r=-0.11), fat mass (r=-0.13), percent body fat (r=-0.11); all p<0.05. Only change in waist circumference was correlated with gTL in Whites subjects (r=-0.12, p=0.02). At baseline, Black (n=55) and White (n=97) subjects with metabolic syndrome had significantly shorter mean gTL compared to those without (p<0.05). Furthermore, gTL was negatively correlated with number of baseline metabolic syndrome components in Whites (r=-0.12, p=0.02), but not Blacks. In response to training, gTL was negatively correlated with change in number of metabolic syndrome components in Whites (r=-0.10, p=0.044), but positively correlated in Blacks (r=0.15, p=0.047). CONCLUSIONS: Baseline CRF traits and their response to training were not associated with gTL. Increased central adiposity and metabolic syndrome components are associated with shorter gTL in Whites. The gTL estimate used may not be optimized in Blacks and perhaps not sensitive enough to fully capture hypothesized associations with fitness traits or metabolic health.