Race-specific associations between health-related quality of life and cellular aging among adults in the United States: evidence from the National Health and Nutrition Examination Survey.

Purpose: Poor health-related quality of life (HRQOL) could lead to higher morbidity and mortality through telomere attrition or accelerated cellular aging. We conducted a cross-sectional analysis to examine the relationship between four dimensions of HRQOL and leukocyte telomere length (LTL) among a nationally representative sample of 3547 US adults (≥20 years) using the data from the 2001-2002 National Health and Nutrition Examination Survey.
Method: We used HRQOL survey information collected on individuals' self-rated general health, recent physical health, recent mental health, and recent activity limitation. Telomere length was assessed using quantitative polymerase chain reaction. Multiple linear regressions were used to estimate the relationship between each dimension of HRQOL and log-transformed values of LTL with adjustment for sample weights and design effects.
Results: HRQOL-race interactions were significant, and the results were stratified by race. After controlling for demographic factors, disease conditions, and lifestyle variables, worse general health was significantly associated with shorter LTL for Blacks (coefficient, β: -0.022, 95% Confidence Interval, 95% CI: -0.03 to -0.01), but not for Whites or Mexican Americans. Unwell physical health was associated with shorter telomere length for Whites (β: -0.005, 95% CI: -0.01 to -0.001) only. Unwell mental health showed no significant association with LTL in any race.
Conclusions: Although longitudinal studies are needed to prove causality, our findings suggest that HRQOL could be associated with LTL shortening. We also found a possible racial difference in this association and recommend additional multiethnic studies to confirm this and to understand the reasons and consequences of this difference.