Purpose: Hypertension and diabetes are common comorbidities present at breast cancer diagnosis, which may account for half of the Black-White breast cancer survival disparity. Having a coordinated team of medical providers to manage both breast cancer and comorbidities for patients can improve care quality and outcomes; however, these relationships are understudied. Therefore, we examined 1) type of medical provider involved in diabetes and hypertension clinical care management and 2) whether type of physician team was associated with optimal clinical care management of diabetes and hypertension during breast cancer care. Methods: We used medical and pharmacy records and interview data from the Women’s Circle of Health Follow-Up Study, an ongoing population-based cohort of Black breast cancer survivors. Women with diabetes or hypertension for at least one year prior to breast cancer diagnosis (2012-2016) were included (N=274). Optimal diabetes management was categorized as physician order of HbA1c test, LDL-cholesterol test, and medical attention for nephropathy; and optimal hypertension management was categorized as physician order of lipid screen and prescription for hypertension medications within the 12-months post cancer diagnosis. Visits with any cancer specialist, primary care provider, or medical specialist were examined and then categorized as shared care (visits with both a cancer specialist and primary care physician and/or medical specialist) or cancer specialist only. The likelihood of receiving optimal clinical care management for either diabetes and hypertension during breast cancer care was compared by type of physician team using multivariable binomial regression, adjusting for age and health insurance at diagnosis, cancer stage, and comorbidity type and disease severity. Results: 86% of patients had a primary care visit in the 12-months after diagnosis. Most clinical care for comorbidities were managed by primary care providers (diabetes tests: 65% HbA1c, 88% LDL- cholesterol, 60% microalbuminuria; hypertension: 88% lipid screen, 85% hypertension medications). Half of all measures were ordered within 6 months of diagnosis. Only half (49%) of patients received optimal comorbid clinical care management and 90% received shared care. Patients with shared care were four times more likely to have optimal clinical care management for diabetes and hypertension compared with patients who only saw cancer specialists (aRR: 4.41; 95% CI: 1.57, 12.34). Conclusions: These findings are important in that shared care may promote optimal clinical care management for diabetes and hypertension and lead to reduced mortality and improved outcomes, particularly for racial/ethnic minority patients with a greater burden of chronic conditions. Future research is needed to explore the processes of shared care to determine whether medical providers are performing clinical care independently or if providers are communicating to coordinate patients’ care.

Citation Format: Michelle Doose, Michael B. Steinberg, Cathleen Y. Xing, Yong Lin, Joel C. Cantor, Chi-Chen Hong, Kitaw Demissie, Elisa V. Bandera, Jennifer Tsui. Examining medical providers’ involvement in diabetes and hypertension clinical care management of Black breast cancer patients [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D070.