ATLANTA — Higher prescription statin copayments have unintended negative consequences, Teresa B. Gibson, Ph.D., said at the annual meeting of the American College of Cardiology.
Her study of the health records of more than 93,000 statin users in employer-sponsored health plans demonstrated that higher copays were associated with significantly lower medication adherence, which in turn was linked to more emergency department visits and cardiovascular hospitalizations.
Health plan managers and policy makers use copays as a means of controlling prescription drug costs. It's a strategy designed to reduce consumption of prescription drugs and steer patients to preferred, less expensive medications. The use of copays is likely to continue to rise. But in patients with chronic medical conditions—such as known cardiovascular disease, or hyperlipidemia predisposing to heart disease—it's a strategy with troublesome side effects, according to Dr. Gibson of Thomson Medstat, a health care research services company in Ann Arbor, Mich.
“In this large cohort of continuing users of statins, we saw increasing drug copayments are a financial barrier to statin adherence. Reduced cost-sharing might be an effective intervention for these patients,” she observed.
The average statin copay during the study period of 2000–2003 was $12 per month. Overall adherence to statin therapy during the first 18 months was 58%, meaning only 58% of the 93,296 patients had a filled statin prescription on at least 80% of days during follow-up. Higher copays were associated with a 37% reduction in adherence.
Total expenditures measured during the second 18 months of the study period did not differ significantly between statin-adherent and nonadherent patients. Adherent patients had lower medical expenditures, but this was counterbalanced by higher prescription drug expenditures and more physician office visits than for nonadherent patients.
On the other hand, nonadherent patients had more adverse outcomes during the second 18 months as evidenced by significantly more emergency department visits, total hospitalizations, and cardiovascular hospitalizations. Dr. Gibson's study was funded by Pfizer.