Should eligibility for medication therapy management be based on drug adherence?

Abstract

Medicare Part D prescription drug plans must offer medication therapy management (MTM) services to qualified enrollees. Eligibility criteria used by plan sponsors are restrictive, and fewer than 10% of Part D enrollees receive MTM services. The extent to which plan criteria identify beneficiaries most at risk for suboptimal medication use is unknown. To (a) evaluate potential underuse of and poor adherence to evidence-based medications used in the treatment of Medicare beneficiaries with diabetes, heart failure, and chronic obstructive pulmonary disease (COPD) over 3 years; (b) determine whether MTM eligibility criteria used by the modal Part D plan in 2011 (drug spending ≥ $3,000, ≥ 3 chronic conditions, ≥ 8 Part D medications) identified Part D enrollees at greatest risk for underuse of and poor adherence to these drugs; and (c) demonstrate how sensitive MTM eligibility is to variations in criteria levels. Study subjects were selected from a 5% random sample of Part D enrollees with 1 or more of these diseases in 2006 and followed through 2008 or death. Longitudinal patterns of exposure and adherence to angiotensin-converting-enzyme inhibitor/angiotensin receptor blockers, beta-blockers, and COPD controller drugs were tracked comparing patterns for enrollees meeting/not meeting the modal 2011 MTM eligibility criteria. Use of evidence-based medication was consistently suboptimal for every disease cohort studied. Higher rates of exposure and adherence were observed among those with high drug spending taking multiple Part D drugs. Current MTM criteria were found to target beneficiaries with above average utilization of evidence-based medication and to exclude those with more problematic utilization patterns. We estimate that lowering the maximum required drug count from 8 to 2 would increase the percentage of beneficiaries eligible for MTM by two thirds. Our findings suggest that MTM eligibility criteria are not optimally targeted to capture underuse of and poor adherence to evidence-based medications. Policymakers should weigh the pros and cons of loosening restrictive MTM eligibility criteria to target patients with potentially greater needs.