Changes in vitamin and mineral supplement use after breast cancer diagnosis in the Pathways Study: a prospective cohort study
1 Mailman School of Public Health, Columbia University, New York, NY 10032, USA
2 Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032, USA
3 Division of Research, Kaiser Permanente Northern California, Oakland, CA 94612, USA
4 University of California San Francisco, San Francisco, CA 94143, USA
5 Group Health Research Institute, Seattle, WA 98101, USA
6 Roswell Park Cancer Institute, Buffalo, NY 14263, USA
7 College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
BMC Cancer 2014, 14:382 doi:10.1186/1471-2407-14-382Published: 29 May 2014
Vitamin and mineral supplement use after a breast cancer diagnosis is common and controversial. Dosages used and the timing of initiation and/or discontinuation of supplements have not been clearly described.
We prospectively examined changes in use of 17 vitamin/mineral supplements in the first six months following breast cancer diagnosis among 2,596 members (28% non-white) of Kaiser Permanente Northern California. We used multivariable logistic regression to examine demographic, clinical, and lifestyle predictors of initiation and discontinuation.
Most women used vitamin/mineral supplements before (84%) and after (82%) diagnosis, with average doses far in excess of Institute of Medicine reference intakes. Over half (60.2%) reported initiating a vitamin/mineral following diagnosis, 46.3% discontinuing a vitamin/mineral, 65.6% using a vitamin/mineral continuously, and only 7.2% not using any vitamin/mineral supplement before or after diagnosis. The most commonly initiated supplements were calcium (38.2%), vitamin D (32.01%), vitamin B6 (12.3%) and magnesium (11.31%); the most commonly discontinued supplements were multivitamins (17.14%), vitamin C (15.97%) and vitamin E (45.62%). Higher education, higher intake of fruits/vegetables, and receipt of chemotherapy were associated with initiation (p-values <0.05). Younger age and breast-conserving surgery were associated with discontinuation (p-values <0.05).
In this large cohort of ethnically diverse breast cancer patients, high numbers of women used vitamin/mineral supplements in the 6 months following breast cancer diagnosis, often at high doses and in combination with other supplements. The immediate period after diagnosis is a critical time for clinicians to counsel women on supplement use.