ASPO Abstracts
Oxidative stress and breast tissue composition in adolescent girls and their mothers
Category: Molecular Epidemiology & Environment
Conference Year: 2022
Abstract Body:
Purpose of the study: Oxidative stress has been implicated in both the initiation and progression of breast cancer and might mediate associations of environmental and lifestyle factors with breast cancer risk. Yet, there is limited data on the relationship between oxidative stress and breast tissue composition (BTC) across the lifecourse.Methods: In a cohort of 216 Black and Hispanic mother-daughter dyads in New York City, we examined if urinary concentration of 15-isoprostane F2t ng/ml (adjusted for specific gravity and log transformed), a sensitive and specific marker of oxidative stress, is associated with breast tissue composition in adolescent girls (11-20 years) and their mothers (29-55 years). We used optical spectroscopy to measure BTC, including water, collagen, and optical index, which positively correlate with breast density, and lipid, which negatively correlates with density. We collected urine samples and anthropometry measurements on the same day as optical spectroscopy. We used generalized estimated equation models to account for repeated measures in some daughters (20%) and mothers (16%). Models were adjusted for age and body mass index (BMI), and we tested for additive interactions by these factors.Results: Overall, a higher urinary concentration of 15-isoprostane F2t was associated with lower water content in the breast tissue of both daughters (β=-1.69, 95% CI=-3.15,-0.22) and mothers (β=-1.64, 95% CI=-2.91,-0.37). No overall associations were found with collagen, lipid, or optical index. In daughters, we found that 15-isoprostane F2t was associated with lower optical index in girls with a BMI ≥30 kg/m2 (β=-0.37, 95% CI=-0.72,-0.02), but not in girls with a BMI <30 kg/m2 (interaction p-value<0.05). In mothers, a statistically significant additive interaction with BMI was found for collagen content, such that the association was positive, but not statistically significant, in women with a BMI <30 kg/m2 and negative, but not statistically significant, in women with a BMI ≥30 kg/m2 (interaction p-value<0.05).Conclusions: Results suggest that oxidative stress might be associated with BTC in adolescence and adulthood and possibly dependent on body size. Prospective studies with repeated measures are needed to explore associations further.
Keywords: oxidative stress; breast tissue composition; windows of susceptibility for breast cancer