Purpose: 

Diabetes and hypertension are two common comorbidities that affect breast cancer patients, particularly Black women. Disruption of chronic disease management during cancer treatment has been speculated. Therefore, this study examined the implementation of clinical practice guidelines and health outcomes for these comorbidities before and during cancer treatment.

Methods: 

We used a population-based, prospective cohort of Black women diagnosed with breast cancer (2012-2016) in New Jersey (n = 563). Chronic disease management for diabetes and hypertension was examined 12 months before and after breast cancer diagnosis and compared using McNemar’s test for matched paired and paired t tests.

Results: 

Among this cohort, 18.1% had a co-diagnosis of diabetes and 47.2% had a co-diagnosis of hypertension. Implementation of clinical practice guidelines and health outcomes that differed in the 12 months before and after cancer diagnosis included lipid screening (64.5% before versus 50.0% after diagnosis; p = 0.004), glucose screening (72.7% versus 90.7%; p < 0.001), and blood pressure control < 140/90 mmHg (57.6% versus 71.5%; p = 0.004) among patients with hypertension-only. For patients with diabetes, eye and foot care were low (< 35%) and optimal HbA1c < 8.0% was achieved for less than 50% of patients in both time periods.

Conclusion: 

Chronic disease management continued during cancer treatment; however, eye and foot exams for patients with diabetes and lipid screening for patients with hypertension-only were inadequate. Given that comorbidities may account for half of the Black-White breast cancer survival disparity, strategies are needed to improve chronic disease management during cancer, especially for Black women who bear a disproportionate burden of chronic diseases.