Background:
Leukocyte telomeres are biological markers of cellular aging. Shorter telomeres are associated with cardiovascular disease and reduced longevity. Psychosocial stress (e.g., perceived discrimination) is also associated with shorter telomeres, which contribute to aging-related illnesses. African Americans have a high burden of cardiovascular morbidity and mortality, which may be partially explained by experiences of discrimination and their resultant effects on leukocyte telomere length (LTL). Behavioral coping responses to discrimination may alter the effects of discrimination on LTL.
Objective:
To investigate the associations of multiple measures of and coping responses to perceived discrimination with LTL, and determine the extent to which sex, age, and educational attainment modify these associations.
Hypotheses:
We hypothesize that dimensions of discrimination will be inversely associated with LTL, while coping responses will be positively associated with LTL. Additionally, there will be effect modification by sex, age, and educational attainment.
Methods:
Jackson Heart Study participants (21-93 years) from visit 1 (2000-2004) with LTL data were utilized (n=2518). The dimensions of discrimination (everyday, lifetime, burden of lifetime, and stress from lifetime discrimination) were categorized as low (referent), moderate, and high and scored in standard deviation (SD) units. Coping responses to everyday and lifetime discrimination were categorized as emotion-focused (e.g., ignoring discrimination) and problem-focused coping (e.g., speaking out against discrimination). Multivariable linear regression analyses were performed to estimate the mean difference (standard errors-SEs) in LTL by dimensions of discrimination and coping responses. Covariates were age, sex, education, smoking and cardiovascular disease status. Effect modification by sex, age, and educational attainment was performed.
Results:
Mean LTL was 7.18 (kilobase pairs) (SD: 0.69). There were no statistically significant associations between dimensions of discrimination nor coping responses and mean LTL in unadjusted and fully adjusted models. However, after full adjustment, high (vs. low) stress from lifetime discrimination was associated with lower mean LTL among those aged 35-44 (vs. <35) (b=-0.292, SE=0.09;
p
= 0.001). Moderate (vs. low) burden of lifetime discrimination was associated with higher mean LTL among women and participants age 35-44 (p=0.009). Additionally, moderate everyday and lifetime discrimination was associated with higher mean LTL among those with high school diplomas and college degrees (vs. <high school diploma) (b=0.104, SE=0.053;
p
= 0.048 and b=0.103, SE=0.053;
p
= 0.047 respectively).
Conclusion:
Experiences of discrimination may be a risk factor for shorter LTL, when considering differences in age, sex and educational attainment.