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. © 2009 by American Society of Clinical Oncology.