Sociodemographic correlates of change in leukocyte telomere length during mid- to late-life: The Multi-Ethnic Study of Atherosclerosis.

Although epidemiologic studies of telomere length have become increasingly common, few population-based, multi-ethnic studies include data on telomere shortening, which may be a better predictor of morbidity and mortality than a single measure of telomere length. This study used stored blood samples from 1169 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) to examine age, sex, race/ethnicity, marital status, income, and education as predictors of change in telomere length over a 10-year period in linear mixed effects models. Mean age at baseline was 61 years, and the sample was 54% female, 27% white, 30% African-American, and 43% Hispanic. At baseline, 58% of the sample was married; 32% had household income below $25,000 per year, 35% had income between $25,000 and $49,999 per year, and 34% had income above $50,000 per year; 41% had a high school education or less, 30% had some college, and 29% had a college degree or more. Relative telomere length (T/S ratio) was measured by the quantitative polymerase chain reaction method. In general, ten-year telomere attrition was greater for groups that had longer telomere length at baseline, including younger people, whites, and women. After adjusting for baseline telomere length, race/ethnic differences in telomere attrition were attenuated, and age and sex differences were reversed, such that older people and men showed greater telomere shortening. There were no significant differences in telomere attrition by marital status, income, or education. There is not yet a consensus in the field regarding whether to adjust for baseline telomere length in models examining predictors of telomere attrition. To ensure comparability across studies, researchers should report results both with and without adjustment for baseline telomere length.