Doubling Prescription Drug Copays Reduces Use, Increases Risk, Study Finds

Doubling copayments for prescription drugs is associated with decreased use of eight types of medications for common chronic diseases and a rise in emergency department visits and hospitalizations, according to a study published in Wednesday's Journal of the American Medical Association, the Wall Street Journal reports (Fuhrmans, Wall Street Journal, 5/19). For the study, researchers examined prescription drug data for 528,969 members of 52 health plans offered by 30 large U.S. employers between 1997 and 2000. According to lead author Dana Goldman, director of health economics at RAND Health, and colleagues, health plans have been increasing prescription drug copays to reduce spending. Between 2000 and 2003, the average copay for prescription drugs on a health plans' formulary rose 46% to $19, compared with an increase of 71% to $29 for nonpreferred drugs, according to a survey of employers by the Kaiser Family Foundation and Health Research and Educational Trust. The average copay for generic drugs rose 28% to $9, the study notes (Reuters, 5/18).

Researchers found that when copays doubled, use of prescription drugs fell between 17% and 23% among patients with diabetes, asthma and gastric acid disease. At the same time, ED visits rose 17% and hospital stays increased 10% for the same patients, the study says (Wall Street Journal, 5/19). The largest decrease in medication use related to increasing copays -- 45% -- occurred among people who took nonsteroidal anti-inflammatory drugs for arthritis, the study says. According to the study, purchases of antihistamines for allergies decreased 44%, cholesterol-lowering drugs 34%, anti-ulcer drugs 33%, asthma drugs 32%, hypertension medication and anti-depressants 26% and diabetes medications 25% in response to increased copays (Ricks, Long Island Newsday, 5/19). The study also found that patients were selective in choosing medications to limit doubling of copays. For instance, patients with high blood pressure reduced their use of antihypertensive drugs by only 10%, compared with a reduction of 27% for other medications. Patients responding to higher copays were more likely to reduce prescription drug use for conditions with symptoms that could be treated with over-the-counter remedies, the study notes. The study was funded in part by Merck.

Goldman said that raising copays "is a blunt tool for changing people's use of prescription medicine," adding, "If we want to change the patterns of drug use so that we don't adversely affect patient's health, that will require more sophisticated benefit designs" (Reuters, 5/18). The Journal reports that the researchers do not advocate avoiding copay increases and instead believe that a "tiered copay system can reduce excess use of drugs for which there are cheaper, effective generic or over-the-counter alternatives." Joe Martingale, a health care strategist at Watson Wyatt, said, "We have to work on (refining copay plans), not condemn them, and that's the challenge" (Wall Street Journal, 5/19). Mark Merritt, president of the Pharmaceutical Care Management Association, noted in a statement on Wednesday, "Consumers are most price sensitive for prescriptions addressing symptoms or conditions with close over-the-counter substitutes" (Long Island Newsday, 5/19). An abstract of the study is available online. MPR's "Marketplace Morning Report" on Wednesday reported on the study. The segment includes comments from study contributor Geoffrey Joyce (Palmer, "Marketplace Morning Report," MPR, 5/19). The complete segment will be available online in RealPlayer after the broadcast.