Changes in Drug Utilization for Seniors without Prior Prescription Drug Insurance
Grant Description: The researchers assessed changes in prescription drug use among elderly patients who had no prescription drug coverage prior to Medicare Part D. In particular, they examined the following research questions: 1) How fast is the uptake of Medicare Part D among seniors without prior insurance? Is there an increase in preventive drug use (more new users, better adherence)? 2) Is there switching to more effective or more expensive drugs? 3) Is there a reduction in discontinuation of drugs for chronic conditions? 4) To what extent does total drug spending per patient change? 5) What proportion of spending is shifted from patients to Medicare? 6) Are prescribing changes clustered within physicians, pharmacies, or chains? 7) How do prescribing patterns change when some patients exhaust their initial coverage but have not yet reached the catastrophic coverage (in the “doughnut hole”)? The objective of the study was to influence discussion of how to improve Medicare drug coverage after the first year of its existence by providing timely methodologically rigorous evidence.
Policy Summary: As of June 2006, 22.5 million seniors had enrolled in a Medicare Part D prescription drug plan (citation omitted). While surveys of Medicare Part D enrollees have been conducted, no study to date has evaluated the effects of enrollment in Medicare Part D on actual drug use and out-of-pocket spending by subjects who were previously without drug insurance (citation omitted). This study sought to assess the effect of Medicare Part D on the utilization of selected essential drugs among seniors previously lacking drug benefits using data from three large pharmacy chains. The researchers’ analysis of this large-scale natural experiment showed that the implementation of the Medicare Part D benefit was associated with a substantial reduction in out-of-pocket spending for prescription drugs, and a meaningful increase in use of selected essential medications, including statins, clopidogrel, and warfarin, in patients who opted to enroll in Medicare Part D plan in 2006. Relative to the projected 2005 trends, warfarin, clopidogrel, and statin use in 2006, measured in daily doses dispensed, increased by 5 percent, 18 percent, and 28 percent. Proton-pump inhibitors (PPIs), a medication class that is frequently overused, experienced the steepest increase in use (58 percent) with the introduction on Medicare Part D which could potentially reflect patients switching from over-the-counter PPIs to prescription PPIs (citation omitted). There was a rapid uptake of newly marketed generic medications by the Part D plans such as generic statins and clopidogrel. The benefit was not evenly distributed throughout the year. Among the 11 percent of patients who reached the coverage gap, utilization of clopidogrel, warfarin, and statins decreased at roughly 5 percentage points per month relative to the baseline trend. Consequently, overall utilization of statins and clopidogrel, drugs with proven effectiveness in reducing severe morbidity, declined to a volume almost as low as without Part D coverage. In conclusion, the first year of Medicare Part D was a mixed blessing for elderly patients without prior drug benefits. To the credit of the benefit, patients who enrolled were more likely to use essential medications, including clopidogrel, statins, and warfarin that are likely to result in better health outcomes. However, a sizable proportion of sicker patients reached the coverage gap in the first year and experienced a sharp drop in the use of the same drugs, which may result in worse health outcomes. Additionally, while the data suggest that private drug plans stimulate greater generic drug use, there is also evidence that coverage within these plans may not adequately distinguish between under-used essential medications and over-used medications. If the goal of the Part D benefit is to provide access to highly effective prescription drugs to seniors most efficiently, efforts to close the coverage gap, coupled with formulary designs that better differentiate between the value and effectiveness of covered medications, may assist in optimizing coverage and the health of our seniors.