Discontinuation of VA Pharmacy Use for Chronic Medications after the Copayment Increase

Smith BM, Stroupe KT, Lee TA, Tarlov E, Huo Z. Discontinuation of VA Pharmacy Use for Chronic Medications after the Copayment Increase. Paper presented at: VA HSR&D National Meeting; 2007 Feb 22; Arlington, VA.

Related HSR&D Project(s)

• IIR 03-200 – VA Prescription Drug Company Copayments and Veterans with Diabetes or Hypertension

Objectives: To examine the impact of the medication copayment increase from $2 to $7 per 30-day supply in February 2002 on the probability of discontinuing use of Department of Veterans Affairs (VA) pharmacies for medications to treat chronic illnesses. Veterans are subject to copayments for no, some, or all medications from VA based on their income and the extent to which their disability and specific conditions are related to their prior military service. Methods: We collected VA pharmacy and utilization data for a sample of 155,199 male VA users from fiscal years 2001-2002. The study design was a retrospective observational study. Multivariable logistic regression models were used to examine the association of copayment group (i.e., copayments for no, some, or all medications) and discontinuation while controlling for patient characteristics (e.g. race, age, comorbidities). Results: Veterans who had copayments for all medications were more likely than veterans with no copayment medications to discontinue VA pharmacy use for medications to treat hypertension (OR = 1.28, 95% CI: 1.16 – 1.42), angina (OR = 1.41, 95% CI: 1.25 – 1.60), depression (OR = 1.57, 95% CI: 1.20 – 2.06) and psychosis (OR = 2.39, 95% CI: 1.88 – 3.05). Veterans with copayments for some medications were also more likely than veterans with no copayments to discontinue use of VA pharmacies for these classes of medications. There were no statistically significant (p < 0.01) associations between copayment level and discontinuation of anticoagulants, lipid-lowering agents, antiarrhythmics, or medications to treat diabetes. Implications: A small increase in copayment for medications was associated with a substantial likelihood of stopping the use of VA pharmacy for medications to treat hypertension, angina, depression, and psychosis. Discontinuation of medications could have adverse consequences on health outcomes and overall health care costs for veterans, particularly for those veterans on chronic medications for hypertension or depression. Impacts: The finding that veterans’ use of the VA pharmacy for chronic medications is sensitive to a copayment increase raises important questions about potential unintended health consequences. VA policymakers may want to consider the potential for unintended, adverse effects of future copayment increases on medication discontinuation before increasing copayments further.