Abstract PS2-22: Impact of Co-payments on Patient Compliance and Persistence for Smoking Cessation Pharmacotherapy

Background/Aims: Increasing patient co-payments commonly cause decreased medication adherence.This analysis evaluated the impact of co-payment on patient compliance and persistence with smoking cessation pharmacotherapy.Methods: Patients were identified from the Lovelace Health Plan (LHP) from January 1, 2000, to June 30, 2005, by a bupropion prescription claim (<300 mg/day), exclusive of a diagnosis for a mood disorder (ICD-9 311.X), with no more than 9 refills and with continuous enrollment 3 months prior and 12 months post the initial fill date.Patients were grouped into three co-payment groups: <$10, >$10 to <$20 and >$20.Compliance was calculated as the days of available therapy over indicated therapy (49 days) and persistence as the percentage of patients remaining on therapy at 15, 49 and 60 days.Patients were stratified by age, gender, ethnicity and comorbidities.Resource use and costs were collected for each group.Results: The study population consisted of 1732 subjects with 496, 330 and 292 in each of the co-payment categories and a cohort of 613 patients for whom the co-pay was not available.Patients who paid <$10 were the least compliant, with a medication possession ratio (MPR) of 0.7325 (CI, 0.7164-0.7486),and those who paid >$20 were the most compliant, with an MPR of 0.7646 (CI, 0.7614-0.8084).Compliance was associated with gender (0.7654 female vs. 0.7419 male), age (0.7634 age 40-64 vs. 0.7370 age 18-39), and ethnicity (0.7650 non-Hispanic vs. 0.7220 Hispanic).Persistence at 15 days was almost 100% for all three tiers.Persistence at 49 days was 0.3919 (CI, 0.3559-0.4424)for the lowest co-pay cohort and 0.5358 (CI, 0.4784-0.5933,P<0.001) for the highest co-pay cohort.Persistence at 60 days followed the same trends as at 49 days.Females aged 40-64 and non-Hispanics demonstrated greater persistency.The impact of age, gender, ethnicity, and comorbidities on the results will be presented along with the resource use and cost distributions between groups.Conclusions: The more common relationship of increased cost-sharing to decreased adherence seen in other disease states may be the inverse for smoking cessation pharmacotherapy.Patient behavioral components, such as motivation to quit, may play a larger role.