Nonadherence to Noncancer Medication Schedules Predicts Adherence to Adjuvant Hormone Therapy for Breast Cancer
Patients who do not adhere to their medication schedules for chronic conditions prior to a breast cancer diagnosis were twice as likely to skip oral adjuvant hormonal therapy.1
The nonadherence rate for hormone treatment was 23% in patients who skipped medications for chronic conditions such as hypertension, diabetes, and thyroid disease compared with 10% for those who took one or more drugs for their conditions prior to a breast cancer diagnosis.
These are the first findings to associate prior medication adherence patterns with subsequent adherence for breast cancer drug therapy.
Researchers from the Columbia University Mailman School of Public Health and Columbia University Medical Center and NewYork-Presbyterian, in New York, New York, used the MarketScan database for this retrospective cohort study. Data on 21 255 women treated with adjuvant hormonal therapy was included. The women were age 18 years or older, with breast cancer diagnosed in 2010-2012, and had filled 2 or more prescriptions for tamoxifen and/or an aromatase inhibitor. Overall, 16% of patients were nonadherent to their hormone replacement therapy.
"Given the fact that medications used in oncology are potentially life-saving or life-prolonging, it is surprising that nonadherence to these medications is common," said Alfred I. Neugut, MD, PhD, Myron M. Studner Professor of Cancer Research and professor of epidemiology at the Mailman School of Public Health, and lead author of the study.
Patient age had a strong association with adherence rates, with the highest adherence rates among women age 55 to 64 years and lower adherence rates among women younger than 45 years or older than 75 years. In addition, adherence was less likely among women who were African American, treated by a specialist other than a medical oncologist, had poor belief in the treatment's efficacy, lower financial resources, and higher co-payments for the drug. Nonadherence gradually increased as the 30-day out-of-pocket costs rose to more than $5.
"Those who are nonadherent to chronic medications are at increased risk for nonadherence to hormone therapy and could benefit from vigilance and possible future interventions," noted Neugut.
"Nonadherence to hormone therapy for breast cancer can have significant impact on survival outcomes," said Neugut. "The hope is that by identifying patients at highest risk for nonadherence and having a detailed history of medication use, interventions can be developed and targeted at higher-risk groups."
1. Neugut AI, Zhong X, Wright JD, et al. Nonadherence to medications for chronic conditions and nonadherence to adjuvant hormonal therapy in women with breast cancer [published online June 9, 2016]. JAMA Oncol. doi:10.1001/jamaoncol.2016.1291.