Association of Neighborhood Deprivation With Epigenetic Aging Using 4 Clock Metrics.

Importance: Neighborhood deprivation is associated with age-related disease, mortality, and reduced life expectancy. However, biological pathways underlying these associations are not well understood. Objective: To evaluate the association between neighborhood deprivation and epigenetic measures of age acceleration and genome-wide methylation. Design, Setting, and Participants: This cross-sectional study used data from the Sister Study, a prospective cohort study comprising 50 884 women living in the US and Puerto Rico aged 35 to 74 years at enrollment who had a sister with breast cancer but had not had breast cancer themselves. Cohort enrollment occurred between July 2003 and March 2009. Participants completed a computer-assisted telephone interview on demographic, socioeconomic, lifestyle, and residential factors and provided anthropometric measures and peripheral blood samples at a home examination. DNA methylation data obtained for 2630 non-Hispanic White women selected for a case-cohort study in 2014 were used in this cross-sectional analysis. DNA methylation was measured using the HumanMethylation450 BeadChips in whole blood samples collected at baseline. Data analysis for this study was performed from October 17, 2019, to August 27, 2020. Exposures: Each participants' primary address was linked to an established index of neighborhood deprivation. Main Outcomes and Measures: Epigenetic age was estimated using 4 epigenetic clocks (Horvath, Hannum, PhenoAge, and GrimAge). Age acceleration was determined using residuals from regressing chronologic age on each of the 4 epigenetic age metrics. Linear regression was used to estimate associations between neighborhood deprivation and epigenetic age acceleration as well as DNA methylation at individual cytosine-guanine sites across the genome. Results: Mean (SD) age of the 2630 participants was 56.9 (8.7) years. Those with the greatest (>75th percentile) vs least (≤25th percentile) neighborhood deprivation had higher epigenetic age acceleration estimated by Hannum (ß = 0.23; 95% CI, 0.01-0.45), PhenoAge (ß = 0.28; 95% CI, 0.06-.50), and GrimAge (ß = 0.37; 95% CI, 0.12-0.62). Increasing US quartiles of neighborhood deprivation exhibited a trend with Hannum, PhenoAge, and GrimAge. For example, GrimAge showed a significant dose-response (P test for trend <.001) as follows: level 2 vs level 1 (ß = 0.30; 95% CI, 0.17-0.42), level 3 vs level 1 (ß = 0.35; 95% CI, 0.19-0.50), and level 4 vs level 1 (ß = 0.37; 95% CI, 0.12-0.62). Neighborhood deprivation was found to be associated with 3 cytosine-phosphate-guanine sites, with 1 of these annotated to a known gene MAOB (P = 9.71 × 10-08). Conclusions and Relevance: The findings of this study suggest that residing in a neighborhood with a higher deprivation index appears to be reflected by methylation-based markers of aging.

Eating Disorders and Breast Cancer.

BACKGROUND: Eating disorders such as anorexia nervosa and bulimia nervosa affect overall and reproductive health and may also affect breast cancer risk. We studied the association between self-reported eating disorders and breast cancer risk in a prospective cohort study. METHODS: In 2003-2009, the Sister Study enrolled women ages 35-74 years who had a sister with breast cancer but had never had it themselves. Using data from 47,813 women, we estimated adjusted HRs and 95% confidence intervals (CI) for the association between eating disorders and invasive breast cancer over a median of 5.4 years of follow-up. RESULTS: Three percent (n = 1,569) of participants reported a history of an eating disorder. Compared with women who never had an eating disorder, women who reported eating disorders in the past had reduced breast cancer risk (HR = 0.62; 95% CI, 0.42-0.92). CONCLUSIONS: In this large prospective, observational cohort study, we observed an inverse association between having a history of an eating disorder and invasive breast cancer. IMPACT: Historical eating disorders may be associated with a long-term reduction in breast cancer risk. Cancer Epidemiol Biomarkers Prev; 26(2); 206-11. ©2016 AACR.