Smoking and physical inactivity increase cancer prevalence in BRCA-1 and BRCA-2 mutation carriers: results from a retrospective observational study (LIBRE 1 Study)
09 May 2017 (online)
Prospective studies in sporadic breast cancer demonstrate a significant influence of lifestyle and socioeconomic status on cancer risks. The aim of this study was to investigate whether harmful lifestyle factors such as nicotine and alcohol abuse, obesity and physical inactivity, as well as a low socioeconomic status could increase cancer prevalence in a cohort of BRCA 1 and 2 mutation carriers.
The analysis data came from 68 participants of the lifestyle intervention study LIBRE-1, a randomized, prospective trial that aimed to analyse the feasibility of a lifestyle modification in BRCA 1 and 2 mutation carriers. At study entry factors such as medical history, lifestyle behaviour and socioeconomic status were retrospectively documented by interview and the actual BMI was determined by clinical examination. The baseline measurements were compared within the cohort.
Study participants indicating a higher physical activity during their adolescence showed a statistically significant lower cancer prevalence (p = 0.019). A significant increase in cancer occurrence was observed in present and former BRCA positive smokers compared to non-smokers (p < 0.001). Diseased mutation carriers tended to have a lower BMI compared to healthy mutation carriers, whereas last-mentioned revealed a significantly higher physical activity level (p = 0.046). Emphasizing socioeconomic background study participants showed a very high educational level and outstanding net income compared to the German reference group without statistical significance.
Even within this small cohort of 68 women we could demonstrate that smoking and low physical activity during adolescence significantly increased cancer prevalence in BRCA 1 and 2 positive women.