Abstract 278: The Sister Study: Morbid conditions at enrollment in a breast cancer cohort

The Sister Study is a prospective cohort of 50,884 unaffected sisters of women diagnosed with breast cancer; given that participants were at increased risk of developing breast cancer, we wanted to investigate the prevalence of other conditions at enrollment. We compared demographic, lifestyle, and selected self-reported morbid conditions between Sister Study participants and women in NHANES, a representative sample of the US population, using age-adjusted prevalence, overall and by race/ethnicity. Demographically, women in the Sister Study are more likely than women in NHANES to be non-Hispanic white, well-educated and to have had higher household incomes. They were also somewhat more likely to have been post-menopausal at enrollment and have ever used hormonal birth control or hormone replacement therapy. The Sister Study has a lower prevalence of current smokers and a higher prevalence of alcohol consumption than among women in NHANES. BMI was lower in the Sister Study. Sister Study participants generally had a lower age-adjusted prevalence of self-reported chronic morbid conditions at baseline than did women in NHANES. For cardio- and cerebrovascular conditions, for example, heart attack and stroke were lower in the Sister Study (0.9% vs. 2.4%; 0.6% vs. 3.1%, respectively) as were self-reported hypertension and high cholesterol (22.8% vs. 34.5%; 28.6% vs. 40.7%). This pattern was similar across all race/ethnicity groups with the exception of angina, which was similar to NHANES overall (2.1% vs. 2.2%). Prevalence of diabetes was lower in the Sister Study (4.9% vs. 9.5%) as were cancers other than breast or non-melanoma skin (4.4% vs. 8.1%) and rheumatoid arthritis (3.3% vs. 6.2%). Again, this was similar across race/ethnicity groups. A few conditions had a higher prevalence in the Sister Study: uterine fibroids, endometriosis, osteoporosis, and allergies (22.0% vs. 13.7%; 12.2% vs. 7.7%; 17.0% vs. 8.6%; and 54.1% vs. 44.2%). Thyroid disease (excluding cancer), asthma, Crohn’s disease, and ulcerative colitis were similar in the Sister Study and NHANES (19.4% vs. 18.5%; 14.6% vs. 15.0%; 0.5% vs. 0.4%; and 1.4% vs. 1.3%). Two or more morbid conditions were reported by just over one third of Sister Study participants. After restriction to college graduates, differences between the Sister study and NHANES were no longer apparent. The few exceptions were differences that would be expected, given Sister Study participants’ ability to participate in a long-term study, healthy behaviors and access to care: lower prevalence of hypertension and high cholesterol; higher prevalence of self-reported fibroids, osteoporosis, and allergies. Although Sister Study participants do differ in a few respects from the NHANES population, the cohort is a unique and well characterized resource, well-suited for research on the incidence of number of chronic conditions, in addition to breast cancer. Note: This abstract was not presented at the meeting. Citation Format: M. Elizabeth Hodgson, Whitney D. Arroyave, Sandra Deming-Halverson, Aimee A. D9Aloisio, Dale P. Sandler. The Sister Study: Morbid conditions at enrollment in a breast cancer cohort [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 278. doi:10.1158/1538-7445.AM2017-278