Changes in health-related behaviours following BRCA 1/2 genetic testing: the case of hormone replacement therapy

To determine hormone replacement therapy (HRT)use among women at high risk for breast cancer and ovarian cancer, before genetic testing for the cancer susceptibility genes BRCA1 and BRCA2, and 1 year following disclosure of the test results.

Participants were 209 French-Canadian women (from 67 high-risk families) who were tested for BRCA1/2 mutations as part of the multidisciplinary research program INHERIT BRCAs (INterdisciplinary HEalth Research International Team on BReast CAncer susceptibility). Use of HRT was recorded at the first genetic counselling session and through a self-administered questionnaire 1 year after result disclosure.

At the genetic counselling session, approximately 15% of women (31/209) reported using HRT, a proportion that is significantly lower than the 25% observed among similarly aged women from the general Quebec population (P < .001). Further analyses, based on the generalized estimating equations models, were carried out to evaluate variations in HRT use from the first genetic counselling session up to 1 year post-disclosure of BRCA1/2 test results. These analyses indicated a trend toward decreased HRT use among BRCA1/2 mutation carriers (P = .08).

Women at high risk for breast cancer and ovarian cancer tend to avoid HRT when BRCA1/2 mutations are either suspected or confirmed. Further studies are needed to assess the actual risk of HRT use among women at high risk of breast cancer, and to develop clinical guidelines regarding its use in this population of women.