New York City, February 18, 2004—Seniors with the most generous drug coverage were more likely than those with no or limited coverage to use the most costly prescription pain medication for osteoarthritis, even when less expensive over-the-counter drugs could be substituted, according to a new study published today on the Health Affairs website. The Commonwealth Fund-supported study by scholars from the University of Pennsylvania and University of Maryland warns that its findings have great implications for the Medicare program when it implements its prescription drug benefit in 2006. If coverage leads to overuse of more expensive prescription drugs, Medicare could experience unexpectedly high costs without a corresponding improvement in health care quality and outcomes. However, the Medicare prescription drug benefit should also help those beneficiaries who need the more expensive drugs to obtain the appropriate medications, the article says. Jalpa Doshi, a health services research scientist with the University of Pennsylvania's Division of General Internal Medicine, and two colleagues analyzed Medicare data on the use of drugs known as COX-2 inhibitors, the pain-relief medications sold under the brand names Celebrex and Vioxx. Total U.S. sales of COX-2 inhibitors were $4.5 billion in 2003. The authors say those medications are no more effective as pain-killers than over-the-counter medications such as ibuprofen. The over-the-counter drugs are, however, more likely to cause gastrointestinal problems, so COX-2 inhibitors are used with patients who are at risk for gastrointestinal bleeding and ulcers. Doshi and colleagues find that the more generous the drug coverage seniors have, the more likely they are to use a COX-2 inhibitor, regardless of their risk factors. For example, risk of gastrointestinal problems had no independent effect on whether seniors with the best drug coverage-between 76 percent and 100 percent of annual drug costs paid by insurance-were prescribed with a COX-2 inhibitor. Those with the best drug coverage and at only moderate risk of gastrointestinal problems had higher rates of COX-2 inhibitor use than those at substantial risk for gastrointestinal problems but with no third-party coverage for drug costs (25 percent vs. 20 percent). "In sum, while drug coverage is clearly associated with greater use of expensive COX-2 inhibitors, most of the increase in use is among those least in need," Doshi says. "Our study suggests that policymakers should also be concerned with potential overuse of drug therapy by Medicare beneficiaries once the benefit is implemented." Medicare also should ensure those beneficiaries at risk for gastrointestinal problems can access COX-2 inhibitor medications. Currently, only 20 percent of seniors without drug coverage at substantial risk of gastrointestinal problems obtain COX-2 inhibitors. Even among those with good drug coverage at substantial risk less than 30 percent receive the more expensive drug, suggesting possible underuse of these medications. "Ideally, the drug benefit should assure that those at greatest need receive appropriate therapy," Doshi says. "At the same time, the application of drug utilization management tools may be required to ensure that costly medications are not excessively used by those for whom less costly substitutes are available." Doshi's coauthors are Nicole Brandt, assistant professor in the Department of Pharmacy Practice and Science at the University of Maryland School of Pharmacy, and Bruce Stuart, a professor in the Department of Pharmaceutical Health Services Research at the University of Maryland pharmacy school.