Profiles of tamoxifen-related side effects by race and smoking status in women with breast cancer

Background: Tamoxifen (TAM) is a selective estrogen receptor modulator (SERM) that is widely used as adjuvant therapy in breast cancer patients; however, it is also associated with undesirable side effects. The goal of this study was to investigate TAM-related side effects, and determine profiles of side effects by race and by smoking status. Methods: A secondary data analysis was conducted using cross-sectional study data from 138 African American and Caucasian women with breast cancer taking TAM 20 mg daily for at least 30 days prior to enrollment. Participants completed questionnaires that obtained information about demographic characteristics, reproductive history, health and lifestyle characteristics, TAM use and its related side effects. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals. Results: Compared to never smokers, a significantly greater percentage of current smokers reported ever experiencing TAM-related nausea (28.0% versus 5.0%, P = 0.007), depression (40.0% versus 7.1%, P = 0.001) and migraines (19.2% versus 1.7%, P = 0.02). These differences remained statistically significant after controlling for race, age, obesity, tumor stage, and duration of TAM treatment. No significant differences by race were noted in women reporting TAM side effects. Conclusion: The findings from this study suggest that current smokers with breast cancer should be informed of the increased probability of reporting TAM-related side effects such as nausea, depression and migraines, and counseled about smoking cessation which may reduce the incidence of these side effects.