Increase in VA Drug Co-Payment Resulted in Decrease in Veterans' Adherence to Some Medications
- A medication co-payment increase from $2 to $7 adversely impacted adherence to statins and anti-hypertensives by Veterans subject to the co-payment, but the impact was greatest among Veterans taking oral hypoglycemic medication. Adherence to all medications increased in the short term for all Veterans (12 months after co-payment increase), but then declined in the longer term (subsequent 11-month period). Authors suggest that the initial increase may have been due to physicians encouraging their patients to stockpile medications in anticipation of the co-payment increase.
- The impact of the co-payment increase was particularly adverse for Veterans with diabetes who were responsible for co-payments. Their adherence to oral hypoglycemic medication in the period 13-23 months after the co-payment increase was 10.3% lower than their pre-period adherence - and 9% lower than comparable Veterans who were exempt from co-payments.
Between 2000 and 2005, average medication co-payments for commercially insured individuals increased, and cost-related medication non-adherence increased along with the higher co-payments. VA's co-payment policy mirrored these market trends by increasing medication co-payments from $2 to $7 for a 30-day fill in February 2002. This study examined the impact of the VA medication co-payment increase on adherence to diabetes, hypertension, and hyperlipidemic medications by Veterans with diabetes or hypertension at 4 VAMCs during a 35-month period (2/01--12/03). Using VA data, investigators compared medication adherence for Veterans who were exempt from co-payments with Veterans who were not exempt, including: 1069 exempt and 1069 non-exempt Veterans with diabetes, 3545 exempt and 3545 non-exempt Veterans with hypertension, and 2029 exempt and 2029 non-exempt Veterans who were prescribed statins. The main outcome measured was adherence to medication at 12 months before and 23 months after the co-payment increase. Exemption from medication co-payment is based upon a Veteran's priority group status.
- Veterans' use of non-VA medications was not assessed, thus it is possible that Veterans were obtaining needed medications via Medicaid or private insurance.
- Since this study, VA has increased medication co-payments to $8. The authors suggest that co-payment increases be carefully considered to ensure that Veterans who have greater comorbidity and lower incomes than the general U.S. population do not forgo needed medications.
This study was funded through HSR&D. Dr. Maciejewski is part of HSR&D's Center for Health Services Research in Primary Care located in Durham, NC.
Maciejewski M, Bryson C, Perkins M, et al. Increasing Co-Payments and Adherence to Diabetes, Hypertension and Hyperlipidemic Medications. American Journal of Medicine January 2010;16(1):