ASPO Abstracts
Patterns of complementary and alternative medicine use and incident risk of breast cancer
Category: Lifestyles Behavior, Energy Balance & Chemoprevention, Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2018
Abstract Body:
Purpose: To examine the association of complementary and alternative medicine (CAM) use patterns with incident risk of breast cancer (BC). Methods: CAM use and breast cancer risk factors were assessed at baseline (2003- 2009) among women in The Sister Study (n=43,172), a prospective cohort study following U.S. and Puerto Rican women with one or more sisters with BC, no personal history of BC, and aged 35-74 years. Incident breast cancer cases were collected through 2016 (Release 5.0). A latent class analysis (LCA) identified patterns of CAM use. Cox regression analyses provided adjusted hazard ratios (AHRs) for breast cancer incidence by LCA-derived CAM patterns. Analyses adjusted for sociodemographic, health, behavioral, and BC risk factors and interaction by menopausal status was examined. A parallel propensity score (PS) matched analyses, to robustly control for confounding, was conducted using 1:1 matching of participants. Results: Six distinct patterns of CAM use were identified. The largest group, labeled very low CAM use, comprised 38% of the cohort and was characterized by minimum use of multivitamins, spirituality/meditation, and therapeutic massage. Other patterns were characterized by predominant use of mind-body practices (13%), multivitamin plus calcium supplements (31%), common nutritional supplements (12%), multiple modalities (3%), and several vitamin and mineral supplements (2%). During 323,407 person-years at risk, we observed 2,320 cases of any BC and 1,731 invasive BC cases. Compared to very low CAM users, women who engaged in mind-body practices (e.g., spirituality/meditation, yoga, therapeutic massage, and chiropractic care) had a reduced risk of any BC (AHR=0.83; 95% Confidence Interval (CI) =0.73-0.96) and of invasive BC (AHR=0.82; 95% CI=0.69-0.96). Multivitamin plus calcium supplement users had a reduced risk of invasive BC (AHR=0.87; 95% CI=0.77-0.98). Findings were consistent across menopausal status. In PS matched analyses, however, multivitamin plus calcium supplement use was not associated with reduced risk of invasive BC. Conclusion: In women at high risk of BC based on family history, use of mind-body practices was associated with a reduced risk of BC. Future studies should explore possible mechanisms related to these findings.
Keywords: Complementary and Alternative Medicine, Breast Cancer