Abstract B42: Racial and ethnic differences in knowledge of risk factors for breast cancer: Findings from a recent national survey
Authors: Breitkopf Carmen Radecki , Rhodes Deborah J. , Jenkins Sarah M. , Ziegenfuss Jeanette Y. , Vachon Celine M. 
Published: May 2015

Background: Racial disparities in breast cancer (BC) outcomes are well-documented. As guidelines for BC screening change, it is particularly important that women have accurate knowledge of risk factors in order to meaningfully participate in screening decisions. We examined knowledge of risk factors for BC among a nationally representative sample of women for whom mammography screening is routinely recommended.

Method: Non-Hispanic black (B), non-Hispanic white (W), Hispanic (H), and women of other/multiple races (O) were surveyed using a probability-based web panel weighted to match the known U.S. population of females aged 40-74 years. A total of 17 items were presented in English or Spanish; response options included: “does not put you at increased risk,” “puts you at a small increased risk,” and “puts you at a large increased risk.” For scoring, the latter two categories were combined to reflect “increased risk.” Items included 9 established risk factors: having mammographically dense breasts, first-degree relative diagnosed with BC, second-degree relative diagnosed with BC, drinking alcohol in excess, history of a breast biopsy, having a first child after age 30, use of hormone therapy for postmenopausal symptoms, BRCA gene mutation, late onset of menopause; 5 protective factors: menarche after age 15, having children, breastfeeding, having a diet rich in fruits and vegetables, exercising or being active; one factor with no clear association: being a smoker (correct response was no increased risk); and 2 distractors (beliefs for which there is no evidence, correct response was no increased risk): using antiperspirant/talc under your arms, experiencing injury/trauma to the breast. The survey cooperation rate was 65% (1,506 responders out of 2,311). Items were scored correct if the respondent's answer matched the actual risk profile (either does/does not put you at increased risk). Percent correct was calculated for each item overall and by race/ethnicity. All reported percentages and analyses are weighted to be nationally representative and compared for differences based on race/ethnicity using logistic regression models. P-values represent differences in percent correct between the racial/ethnic groups.

Results: Knowledge of risk factors varied across items (range &gt;90% to 20% correct). Percent correct was high overall for classifying a first-degree relative with BC as a risk factor and differed by race/ethnicity, with 86% B, 98% W, 92% H and 92% O recognizing this risk factor (p&lt;0.001); similar percentages were observed for second-degree relatives (p=0.003). Lower knowledge overall was observed for risk factors including BRCA mutation (25% B, 44% W, 24% H, 38% O, p=0.002), later onset of menopause (41% B, 38% W, 42% H, 37% O, p=0.92), and having the first child after age 30 (39% B, 41% W, 38% H, 33% O, p=0.53). Having mammographically dense breasts is one of the strongest risk factors for BC, however knowledge of this was only moderate and did not differ by race/ethnicity (61% B, 54% W, 56% H, 52% O, p=0.64). Relative to risk factors, knowledge of protective factors was generally higher; only correct classification of fruits/vegetables as a protective factor differed by race/ethnicity (84% B, 93% W, 88% H, 89% O, p=0.03). Most women correctly responded that use of antiperspirant/talc does not increase risk of BC, however 60% of H women incorrectly classified injury/trauma to the breast as a risk factor, relative to 50% B, 41% W, and 40% O (p=0.02).

Conclusions: Among U.S. women, there is wide variation in knowledge across several established BC risk factors and only moderate knowledge of breast density as an important risk factor. Differences in knowledge by race/ethnicity for several risk factors highlight the need for targeted education.

Citation Format: Carmen Radecki Breitkopf, Deborah J. Rhodes, Sarah M. Jenkins, Jeanette Y. Ziegenfuss, Celine M. Vachon. Racial and ethnic differences in knowledge of risk factors for breast cancer: Findings from a recent national survey. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr B42. doi:10.1158/1538-7755.DISP13-B42