Adjuvant Hormonal Therapy Use Among Insured, Low-Income Women With Breast Cancer

Abstract

Purpose Use of adjuvant hormonal therapy, which significantly decreases breast cancer mortality, has not been well described among poor women, who are at higher risk of cancer-related death. Here we explore use of adjuvant hormonal therapy in an insured, low-income population. Methods A North Carolina Cancer Registry–Medicaid linked data set was used. Women with hormone receptor–positive or unknown, nonmetastatic breast cancer, diagnosed between 1998 and 2002, were included. Main outcomes were (1) prescription fill within 1 year of diagnosis, (2) adherence (medication possession ratio), and (3) persistence (absence of a 90-day gap in prescription fills over 12 months). Results The population consisted of 1,491 women (mean age, 67 years). Sixty-four percent filled prescriptions. Predictors of prescription fill included the following: older age (odds ratio [OR], 1.01; P = .017), greater number of prescription medications (OR, 1.06; P < .001), nonmarried status (OR, 1.82; P = .001), higher stage (OR, 1.83; P < .001), positive hormone receptor status (positive v unknown, OR, 1.98; P < .001), not receiving adjuvant chemotherapy (OR, 1.74; P = .001), receipt of adjuvant radiation (OR, 1.55; P = .004), and treatment in a small hospital (OR, 1.49; P = .024). Adherence and persistence rates were 60% and 80%, respectively. Nonmarried status predicted greater adherence (OR, 1.90; P = .006) and persistence (OR, 1.75; P = .031). Conclusion Prescription fill, adherence, and persistence to adjuvant hormonal therapy among socioeconomically disadvantaged women are low. Improving use of adjuvant hormonal therapy may lead to lower breast cancer–specific mortality in this population.