Anthropometry, silhouette trajectory, and risk of breast cancer in Mexican women

Background Obesity has been associated with breast cancer risk in the Caucasian population but the association remains unclear in the Hispanics. Previous studies conducted among Hispanics in the U.S. have shown inconsistent results. Purpose The association between anthropometry, body shape evolution across lifetime, and the risk of breast cancer was assessed using a multi-center population-based case-control study conducted in Mexico. Methods One thousand incident cases and 1074 matched control women aged 35-69 years were recruited between 2004 and 2007, and analyzed in 2011-2012. Conditional logistic regression models were used. Results Height was related to an increased risk of breast cancer in both premenopausal (p trend=0.03) and postmenopausal women (p trend=0.002). In premenopausal women, increase in BMI; waist circumference (WC); hip circumference (HC); and waist-hip ratio (WHR) were inversely associated with breast cancer risk (p trends<0.001 for BMI and WC, 0.003 for HC, and 0.016 for WHR). In postmenopausal women, decreased risks were observed for increased WC (p trend=0.004) and HC (p trend=0.009) among women with time since menopause <10 years. Further analysis of body shape evolution throughout life showed strong and significant increase in risk of breast cancer among women with increasing silhouettes size over time compared to women with no or limited increase. Conclusions These findings suggest that anthropometric factors may have different associations with breast cancer risk in Hispanic women than in Caucasian women. This study also shows the importance of considering the evolution of body shape throughout life.