3008 — Prescription Drug Copayments and Veterans with Hypertension
Bryson CL (Center for Outcomes Research in Older Adults, VA Puget Sound HCS, Seattle) , Liu CF
(Center for Outcomes Research in Older Adults, VA Puget Sound HCS, Seattle), Perkins M
(Center for Outcomes Research in Older Adults, VA Puget Sound HCS, Seattle), Sharp N
(Center for Outcomes Research in Older Adults, VA Puget Sound HCS, Seattle), Blough D
(School of Pharmacy, University of Washington, Seattle), Stroupe K
(Midwest Center for Health Services and Policy Research, Hines VAMC), Krein S
(Center for Practice Management and Outcomes Research, Ann Arbor VAMC), Fortney J
(Mental Healthcare and Outcomes Research, Little Rock VAMC), Cunningham F
(Pharmacy Benefits Management/Strategic Healthcare Group, Hines VAMC), Maciejewski ML
(Center for Health Services Research in Primary Care, Durham VAMC)
Previous studies in non-VA settings have shown that increasing medication copayments may be associated with changes in medication adherence and health care use and costs for patients with chronic conditions. This study examined effects of the VA medication copayment increase from $2 to $7 for a 30-day supply of medication in February 2001, on medication adherence, health care utilization, and health care costs for veterans with hypertension.
The study included 20,393 veteran patients with hypertension from 4 large, tertiary VA medical centers. Data on demographic characteristics, copay status of veterans, and medication use were drawn from VA national administrative files. Medication adherence was assessed using a modified Steiner medication possession ratio. Generalized Estimating Equations (GEEs) were used to estimate whether the decrease in adherence to medications was greater for veterans who had to pay copayments than for veterans who were exempt from copayments, controlling for demographic characteristics, patient case mix, lagged health care use, number of other medications, VA medical center, and time, with a cluster correction at the patient level.
Compared to veterans who were exempt from medication copayments, veterans always required to pay copayments showed a significantly lower number of primary care encounters, lower primary care costs and lower total outpatient costs following the copayment change (all p<.0001). The medication copayment increase had no significant impact on medication adherence, specialty care, or inpatient utilization and costs.
Our findings indicate that VA’s drug copayment increase from $2 to $7 did not have a significant impact on medication adherence or health services for veterans with hypertension, with the exception of primary care. A $5 increase in medication copayments was not sufficiently large enough to induce non-adherence among veterans required to pay copayments. Decreased primary care and total outpatient costs may have been driven more by increased health care copayments than medication copayments.
While the relatively modest 2002 copayment increase had no effect on medication adherence for patients with hypertension, the potential effect of future medication copayment increases could undermine veterans’ attempts to manage their chronic conditions through medication adherence.