Introduction: The purpose of this study was to investigate potential associations between body composition and current smoking in young healthy women from high-risk families. Cigarette smoke contains >7000 chemicals of which 69 are established carcinogens and smoke also acts as an aromatase inhibitor. Smoking is now recognized as a carcinogen for the breast and influences both risk and prognosis. However, the underlying mechanisms need to be better elucidated. One study showed that breast cancer patients who smoked were younger, had a lower body mass index (BMI), smaller breast volumes, but a higher waist-to-hip ratio (WHR) than non-smokers. However, smoking was also associated with a higher frequency of prior oral contraceptive (OC) use. Since breast cancer development starts long before the tumor is clinically detectable, we aimed to study the impact of cigarette smoke on anthropometric factors. Material and methods: Between 1996 and 2006, 269 healthy women were included in a study on the impact of lifestyle factors in women <=40 years from high-risk breast cancer families. Thirty-six participants who had missing breast measurements or who had undergone previous breast surgeries, who were currently breast-feeding or who were current users of hormonal contraceptives other than combined E+P OCs or had missing smoking status were excluded, leaving 233 women of which 35 were known BRCA1/2 mutation carriers. Height, weight, waist- and hip circumference, and total breast volume were measured in a standardized way by a research nurse 5-10 days before predicted onset of the next menstrual period. Weight, BMI, breast volume, and waist circumference, were not normally distributed and were transformed using the natural logarithm to obtain a better distribution. Multivariable linear regression was used to obtain P-values, adjusted for age, nulliparity, and current OC use. Means and geometric means for smokers and non-smokers were standardized at age 29 years, nulliparity, and non-current OC use. Results: The median age was 29 years (IQR 24-35) and the median year of birth was 1970. Forty-two percent had ever smoked, 23% were current smokers, 28% were current OC users, and 54% were nulliparous. Current smoking was not associated with height, weight, BMI breast volume, or hip circumference (all adjPs=>0.18). However, current smokers had significantly larger standardized waist circumference (78 vs 74 cm; adjP=0.02), and higher standardized WHR (0.79 vs 0.76; adjP=0.003) compared with non-smokers. Conclusion: Current smokers had significantly larger waist circumference and higher WHR, but similar BMI and breast volume compared with non-smokers, although most women had anthropometric measures within WHO’s recommended limits. The difference in fat distribution towards more abdominal fat, suggests that current smoking is associated with a more inflammatory and/or androgenic profile at the age when breast cancer is initiated.

Citation Format: Carolina Ellberg, Håkan Olsson, Helena Jernström. Body constitution in young healthy women from breast cancer higher risk families in relation to smoking [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4291. doi:10.1158/1538-7445.AM2017-4291