Overall and abdominal adiposity and premenopausal breast cancer risk among Hispanic women: The Breast Cancer Health Disparities Study
Menée aux Etats-Unis à partir de données d'études cas-témoins en population incluant 2 023 femmes d'origine hispanique et 2 384 femmes blanches, cette étude évalue les disparités ethniques dans l'association entre l'adiposité, l'indice de masse corporelle et le risque de cancer du sein, en fonction du statut du récepteur hormonal, avant la ménopause
Background: Few studies in Hispanic women have examined the relation between adult body size and risk of premenopausal breast cancer (BC) defined by hormone receptor status. Methods: The Breast Cancer Health Disparities Study pooled interview and anthropometric data from two large U.S. population-based case-control studies. We examined associations of overall and abdominal adiposity with risk of estrogen receptor and progesterone receptor positive (ER+PR+) and negative (ER-PR-) breast cancer in Hispanic and non-Hispanic White (NHW) women, calculating odds ratios (OR) and 95% confidence intervals (CI). Results: Among Hispanics, risk of ER+PR+ BC was inversely associated with measures of overall adiposity, including young-adult and current body mass index (BMI). Risk was substantially reduced among those with high (above the median) young-adult BMI and current overweight or obesity. The findings for overall adiposity were similar for Hispanics and NHWs. In the subset of Hispanics with data on genetic ancestry, inverse associations of current BMI and weight gain with ER+PR+ BC were limited to those with lower Indigenous American ancestry. For ER-PR- BC, height was associated with increased risk, and young-adult BMI was associated with reduced risk. For all BCs combined, positive associations were seen for waist circumference, waist-to-hip ratio, and waist-to-height ratio in Hispanic women only. Conclusions: Our findings of body size associations with specific BC subtypes among premenopausal Hispanic women were similar to those reported for NHW women. Impact: Adiposity throughout the premenopausal years has a major influence on BC risk in Hispanic women.