Implementation Of Medicare Part Research Articles

Market Size and Research: Evidence from the Pharmaceutical Industry

Prior literature has established a link between changes in market size and pharmaceutical innovation; whether a link exists with scientific research remains an open question. If upstream research is not responsive to these changes, the kinds of scientific discoveries that flow into future drug development could be disconnected from downstream demand. We explore this question by exploiting the effects of quasi-experimental variation in market size introduced by Medicare Part D. We find no causal relationship between market size and biomedical research in the decade following the implementation of Medicare Part D. While many factors have been shown to motivate scientists to conduct research, this result suggests that changes in market size provide no such incentive. We do find, however, limited support for a response by corporate scientists conducting applied research. Implications for pharmaceutical innovation policy are discussed.

How access to addictive drugs affects the supply of substance abuse treatment: Evidence from Medicare Part D.

This paper documents how substance abuse treatment (SAT) providers and services respond to increases in population-level opioid addiction. I do this by exploiting the implementation of Medicare Part D as an exogenous increase in the availability of prescription opioids. Starting in 2006, states with higher shares of the population eligible for Medicare Part D experienced increases in residential and hospital inpatient SAT facilities, beds dedicated to SAT, and SAT facilities offering medication-assisted treatment, relative to states with lower shares. These results suggest that the supply of SAT in the United States is capable of responding significantly to changes in demand.

Market Size and Research: Evidence from the Pharmaceutical Industry

Prior literature has established a link between changes in market size and pharmaceutical innovation; whether a link exists with scientific research remains an open question. If upstream research is not responsive to these changes, the kinds of scientific discoveries that flow into future drug development could be disconnected from downstream demand. We explore this question by exploiting the effects of quasi-experimental variation in market size introduced by Medicare Part D. We find no causal relationship between market size and biomedical research in the decade following the implementation of Medicare Part D. While many factors have been shown to motivate scientists to conduct research, this result suggests that changes in market size provide no such incentive. We do find, however, limited support for a response by corporate scientists conducting applied research. Implications for pharmaceutical innovation policy are discussed.

Market Size and Research: Evidence from the Pharmaceutical Industry

Prior literature has established a link between changes in market size and pharmaceutical innovation; whether a link exists with scientific research remains an open question. If upstream research is not responsive to these changes, the kinds of scientific discoveries that flow into future drug development could be disconnected from downstream demand. We explore this question by exploiting the effects of quasi-experimental variation in market size introduced by Medicare Part D. We find no causal relationship between market size and biomedical research in the decade following the implementation of Medicare Part D. While many factors have been shown to motivate scientists to conduct research, this result suggests that changes in market size provide no such incentive. We do find, however, limited support for a response by corporate scientists conducting applied research. Implications for pharmaceutical innovation policy are discussed.

The impact of Medicare Part D on opioid use among U.S. older adults

BackgroundTo assess the association between the implementation of Medicare Part D and the use of outpatient prescription opioids. MethodsNationally representative data on community-dwelling adults aged 60–69 came from the 2000−2015 Medical Expenditure Panel Survey (MEPS) (N = 26,545). A difference-in-differences approach was used to compare opioid use between Medicare eligible (ages 66−69) and Medicare ineligible (ages 60−64) adults before and after the introduction of Part D in 2006, while controlling for socio-demographic characteristics, risk factors for opioid use, and secular trends. ResultsMedicare Part D was associated with a small and statistically non-significant increase in the number of outpatient prescription opioids filled in a year (coefficient, 0.03; 95% CI, -0.08 to 0.13), in the amount of morphine milligrams equivalents (coefficient, 113.23; 95% CI, -25.47 to 251.93), and in the odds of using any prescription opioid (OR, 1.03; 95% CI, 0.85 to 1.26). There was no evidence for a heterogeneous effect of Part D across subgroups. The results were robust to the impacts of the 2007−2009 recession, the spillover effect of the Affordable Care Act, and the anticipation effect of Part D. DiscussionAlthough policymakers suggested that gaining access to medical care as a result of insurance expansion might have fueled the opioid epidemic, this paper found limited evidence to support this claim. While Part D took effect more than a decade ago, its long-term implication for opioid use is still relevant for the recent opioid epidemic and future health insurance expansions such as the proposed Medicare-for-all initiative.

Per-Prescription Drug Expenditure by Source of Payment and Income Level in the United States, 1997 to 2015

ObjectivesTo evaluate expenditures and sources of payment for prescription drugs in the United States from 1997 to 2015. MethodsThe Medical Expenditures Panel Survey (MEPS) was used for this analysis. Individuals with one or more prescription medicines were eligible for inclusion. Outcomes were the inflation-adjusted cost per prescription across all payment sources (self or family, public, private, and other sources) before and after the Medicare Part D benefit and the Affordable Care Act. ResultsThe cost per prescription increased from $38.56 in 1997 to $73.34 in 2015. Nevertheless, consumers’ out-of-pocket expenditures decreased from $18.19 to $9.61, whereas public program expenditures per prescription increased from $5.61 to $34.43 over this time. Out-of-pocket expenditures of individuals in the low-income group and near-poor group had larger declined percentages from 51.4% to 20.4% and 46.5% to 17.2% relative to individuals in higher-income groups before and after implementation of the Medicare Part D, respectively. Over 90% prescription purchases were covered by medical insurance by 2015. The per-prescription cost for medications consumed by uninsured individuals increased at a lower rate from $31.83 to $54.96 versus $40.12 to $75.58 for privately insured and $36.00 to $70.96 for publicly insured (P < .001). ConclusionsPrescription drugs expenditures have increased over the past 2 decades, but public sources now pay for a growing proportion of prescription drugs cost regardless of health insurance coverage or income level. Out-of-pocket expenditures have significantly decreased for persons with lower incomes since the implementation of Medicare Part D and the Affordable Care Act.

The impact of Medicare part D on income-related inequality in pharmaceutical expenditure

BackgroundIncome-related inequality measures such as the concentration index are often used to describe the unequal distribution of health, health care access, or expenditure in a single measure. This study demonstrates the use of such measures to evaluate the distributional impact of changes in health insurance coverage. We use the example of Medicare Part D in the United States, which increased access to prescription medications for Medicare beneficiaries from 2006.MethodsUsing pooled cross-sectional samples from the Medical Expenditure Panel Survey for 1997–2011, we estimated income-related inequality in drug expenditures over time using the concentration and generalised concentration indices. A difference-in-differences analysis investigated the change in inequality in drug expenditures, as measured using the concentration index and generalised concentration index, between the elderly (over 65 years) and near-elderly (54–63 years) pre- and post-implementation of Medicare Part D.ResultsMedicare Part D increased public drug expenditure while out-of-pocket and private spending fell. Public drug expenditures favoured the poor during all study periods, but the degree of pro-poorness declined in the years immediately following the implementation of Part D, with the poor gaining less than the rich in both relative and absolute terms. Part D also appeared to result in a fall in the pro-richness of private insurance drug expenditure in absolute terms but have minimal distributional impact on out-of-pocket expenditure. These effects appeared to be short lived, with a return to the prevailing trends in both concentration and generalised concentration indices several years following the start of Part D.ConclusionsThe implementation of Medicare Part D significantly reduced the degree of pro-poorness in public drug expenditure. The poor gained less of the increased public drug expenditure than the rich in both relative and absolute terms. This study demonstrates how income-related inequality measures can be used to estimate the impact of health system changes on inequalities in health expenditure and provides a guide for future evaluations.

The effect of prescription drug insurance on health behavior: Evidence from Medicare Part D.

This paper provides empirical evidence on the health behavior effect of prescription drug insurance. Using the difference in the regression discontinuity research design, I compare health behavior changes at age 65 before and after the introduction of Medicare Part D. I find that the implementation of Medicare Part D increased prescription drug insurance coverage and reduced out-of-pocket spending per prescription and the use of cardiovascular and metabolic therapeutic class drugs. I also find that Medicare Part D led to a 6.36 percentage point decrease in the probability of engaging in moderate physical exercise and a 27.4 percentage point decrease in the amount of time spent on moderate physical activity. It also increased the probability of being overweight by 5.75 percentage points. Its effects on vigorous and muscle-strengthening exercise both at the extensive and intensive margins, obesity, BMI, and cigarette consumption are not statistically significant.

Associations Between Medicare Part D and Out-of-Pocket Spending, HIV Viral Load, Adherence, and ADAP Use in Dual Eligibles With HIV.

The implementation of Medicare part D on January 1, 2006 required all adults who were dually enrolled in Medicaid and Medicare (dual eligibles) to transition prescription drug coverage from Medicaid to Medicare part D. Changes in payment systems and utilization management along with the loss of Medicaid protections had the potential to disrupt medication access, with uncertain consequences for dual eligibles with human immunodeficiency virus (HIV) who rely on consistent prescription coverage to suppress their HIV viral load (VL). To estimate the effect of Medicare part D on self-reported out-of-pocket prescription drug spending, AIDS Drug Assistance Program (ADAP) use, antiretroviral adherence, and HIV VL suppression among dual eligibles with HIV. Using 2003-2008 data from the Women's Interagency HIV Study, we created a propensity score-matched cohort and used a difference-in-differences approach to compare dual eligibles' outcomes pre-Medicare and post-Medicare part D to those enrolled in Medicaid alone. Transition to Medicare part D was associated with a sharp increase in the proportion of dual eligibles with self-reported out-of-pocket prescription drug costs, followed by an increase in ADAP use. Despite the increase in out-of-pocket costs, both adherence and HIV VL suppression remained stable. Medicare part D was associated with increased out-of-pocket spending, although the increased spending did not seem to compromise antiretroviral therapy adherence or HIV VL suppression. It is possible that increased ADAP use mitigated the increase in out-of-pocket spending, suggesting successful coordination between Medicare part D and ADAP as well as the vital role of ADAP during insurance transitions.

Effects of Prescription Drug Insurance on Hospitalization and Mortality: Evidence from Medicare Part D

AbstractWe used Medicare administrative data (2002–2009) and an instrumental variables design that exploits the natural experiment created by the implementation of Medicare Part D to estimate the effect of prescription drug coverage insurance on the use and costs of inpatient services. We find that gaining prescription drug insurance through Part D caused approximately a 4 percent decrease in hospital admission rate, a 2–5 percent decrease in Medicare inpatient payments per person, and a 10–15 percent decrease in inpatient charges. Among specific types of admissions, gaining insurance was associated with significant decreases in admissions for CHF and COPD.

Socioeconomic Disparities in Mortality Among Women With Incident Breast Cancer Before and After Implementation of Medicare Part D.

Breast cancer patients exhibit survival disparities based on socioeconomic status (SES). Disparities may be attributable to access to expensive oral endocrine agents. Define recent socioeconomic disparities in breast cancer survival and determine whether these improved after implementation of the Medicare Part D program. Difference-in-difference natural experiment of women diagnosed and treated before or after implementation of Medicare Part D. Female Medicare beneficiaries with early-stage breast cancer: 54,772 diagnosed in 2001 and 46,371 in 2007. SES was based on Medicaid enrollment and zip code per capita income, all-cause mortality from Medicare, and cause of death from National Death Index. Among women diagnosed pre-Part D, 40.5% of poor beneficiaries had died within 5 years compared with 20.3% of high-income women (P<0.0001). Post-Part D, 33.6% of poor women and 18.4% of high-income women died by 5 years. After adjustment for potential confounders, improvement in all-cause mortality post-Part D was greater for poorer women compared with more affluent women (P=0.002). However, absolute improvement in breast cancer-specific mortality was 1.8%, 1.2%, and 0.8% (P=0.88 for difference in improvement by SES), respectively for poor, near-poor, and high-income women, whereas analogous improvement in mortality from other causes was 5.1%, 3.8%, and 0.9% (P=0.067 for difference in improvement by SES). Large survival disparities by SES exist among breast cancer patients. The Part D program successfully ameliorated SES disparities in all-cause mortality. However, improvement was concentrated in causes of death other than breast cancer, suggesting remaining gaps in care.

Financial Hardship from Purchasing Medications for Senior Citizens Before and After the Medicare Modernization Act of 2003 and the Patient Protection and Affordable Care Act of 2010: Findings from 1998, 2001, and 2015.

The Medicare Modernization Act of 2003 (Medicare Part D) added prescription drug coverage for senior citizens aged 65 years and older and applied managed care approaches to contain costs. The Patient Protection and Affordable Care Act of 2010 (ACA) had the goals of expanding health care insurance coverage and slowing growth in health care expenditures. To (a) describe the proportion of senior citizens who had prescription drug insurance coverage and the proportion who experienced financial hardship from purchasing medications in 2015, and (b) compare the findings with those collected in 1998 and 2001. Data were obtained in 1998 and 2001 via surveys mailed to national random samples of seniors. Of 2,434 deliverable surveys, 946 (39%) were returned, and 700 (29%) provided usable data. Data were collected in 2015 via an online survey sent to a national sample of adults. Of 26,173 usable responses, 3,933 were aged 65 years or older. Descriptive statistics and logistic regression analyses described relationships among study variables. Results showed that the proportion of seniors without prescription coverage was 9% in 2015, a decrease from 29% in 2001 and 32% in 1998. The proportion of senior citizens reporting financial hardship from medication purchases was 36% in 2015, a rise from 31% in 2001 and 19% in 1998. For those without prescription drug coverage, 34%, 55%, and 49% reported financial hardship in 1998, 2001, and 2015, respectively. For those with drug coverage, 12%, 22%, and 35% reported financial hardship in 1998, 2001, and 2015, respectively. After implementation of Medicare Part D and the ACA, the proportion of seniors without prescription drug coverage decreased. However, self-reported financial hardship from purchasing medications increased. Senior citizens with prescription drug insurance may be experiencing financial hardship from increasing out-of-pocket costs for insurance premiums, cost sharing, and full-cost obligation for some medications. Funding was provided by the American Association of Colleges of Pharmacy New Investigator Program, the University of Minnesota Grant-in-Aid of Research Program, and the Peters Endowment for Pharmacy Practice Innovation. The authors have no conflicts of interest to declare. Schommer, Mott, and Brown contributed to study design and collected the data, with assistance from Olson. Data interpretation was performed by Olson, Schommer, Mott, and Brown. The manuscript was written and revised by Olson, Schommer, Mott, and Brown.

Erectile Dysfunction Medication Use in Veterans Eligible for Medicare Part D.

Erectile dysfunction (ED) medications are therapeutically effective and associated with satisfaction. Medicare Part D included ED medications on the formulary during 2006 and inadvertently in 2007-2008. To characterize phosphodiesterase-5 inhibitor (PDE-5) medication use among veterans who were dually eligible for Veterans Affairs (VA) and Medicare Part D benefits. Veterans aged > 66 years who received PDE-5 inhibitors between 2005 and 2009 were included. Veterans were categorized by PDE-5 inhibitor claims: VA-only, Part D-only, or dual users of VA and Part D-reimbursed pharmacies. T-tests and chi-square tests were applied as appropriate. From 2005 to 2009, the majority (85.2%) of veterans used VA benefits exclusively for their PDE-5 inhibitors; 11.4% used Medicare Part D exclusively; and 3.4% were dual users. The Part D-only group was older, more frequently not black, had a VA copay, and had a higher income (P < 0.03). The VA group was more likely to have comorbidities, smoke, and have a history of substance abuse (P < 0.001). With the inception of Medicare Part D in 2006, the number of patients filling prescriptions for PDE-5 inhibitors (-68%) and total number of PDE-5 inhibitor 30-day equivalents dispensed (-86.7%) from the VA decreased. Part D prescriptions increased through 2006 (full coverage period) and 2007 (accidental partial coverage) and decreased in 2008. While Part D accounted for only 10% of PDE-5 inhibitor 30-day equivalents, it equaled 29.2% of dispensed tablets. In October 2007, VA PDE-5 inhibitor use returned to 2005 levels. Implementation of Medicare Part D reduced VA PDE-5 inhibitor acquisition. However, after removal of PDE-5 inhibitors from the Part D formulary, use of VA pharmacies for PDE-5 inhibitors resumed. Medication policies outside the VA can affect medication use. Veterans with access to non-VA health care may obtain medications from the private sector because of VA restrictions. This may be especially true for nonformulary and lifestyle medications. The authors received funding support for this research project from the Department of Veterans Affairs, Veterans Health Administration, Health Services Research and Development Service as grant IIR 07-165-2. The views expressed in this article are those of the authors and do not necessarily represent the views of the Department of Veterans Affairs or Health Services Research and Development Service. Study concept and design were contributed by Smith and Stroupe, assisted by the other authors. Huo, Bailey, and Stroupe took the lead in data collection, assisted by the other authors. Data interpretation was performed by Spencer and Suda, along with Smith and Stroupe and assisted by Huo and Bailey. The manuscript was primarily written by Spencer and Suda, with assistance from the other authors, and revised by Spencer, along with the other authors.

Payments For Opioids Shifted Substantially To Public And Private Insurers While Consumer Spending Declined, 1999-2012.

Deaths from opioid pain reliever overdose in the United States quadrupled between 1999 and 2013, concurrent with an increase in the use of the drugs. We used data from the Medical Expenditure Panel Survey to examine trends in opioid pain reliever expenditures, financing by various payers, and use from 1999 to 2012. We found major shifts in expenditures by payer type for these drugs, with private and public insurers paying a much larger share than patients in recent years. Consumer out-of-pocket spending on opioids per 100 morphine milligram equivalents (a standard reference measure of strength for various opioids) declined from $4.40 to $0.90 between 2001 and 2012. Since the implementation of Medicare Part D in 2006, Medicare has been the largest payer for opioid pain relievers, covering about 20-30percent of the cost. Medicare spends considerably more on these drugs for enrollees younger than age sixty-five than it does for any other age group or than Medicaid or private insurance does for any age group. Further research is needed to evaluate whether payer strategies to address the overuse of opioids could reduce avoidable opioid-related mortality.

Variation in Prescription Drug Coverage Enrollment Among Vulnerable Beneficiaries With Glaucoma Before and After the Implementation of Medicare Part D.

It is important to understand in more detail how patients with glaucoma were affected by the implementation of Medicare Part D, which was designed to provide beneficiaries with near-universal prescription drug coverage. To determine changes in prescription drug coverage and out-of-pocket spending after the implementation of Medicare Part D across income strata and to identify characteristics of beneficiaries associated with prescription status. Longitudinal observational study in the general community using the Medicare Current Beneficiary Survey (pooled 2004, 2005, 2007, and 2008 data). Participants were noninstitutionalized Medicare beneficiaries who filled at least 1 glaucoma prescription during the survey years. The dates of this analysis were January 2004 to December 2009. Effect of the implementation of the Medicare Part D drug benefit, including prescription drug coverage and risk-adjusted out-of-pocket spending related to glaucoma medications. Respondents included 12,079 participants in the 2004 survey, 11,089 participants in the 2005 survey, 11,995 participants in the 2007 survey, and 11,723 participants in the 2008 survey. The sample included 19,045 glaucoma prescriptions, and 2519 Medicare beneficiaries filled at least 1 glaucoma prescription during the study years. Overall 574 (22.8%) beneficiaries reported living below the poverty level, and 795 (31.6%) had incomes consistent with near-poor status. The implementation of Medicare Part D resulted in increased rates of prescription drug coverage across all economic strata, with reductions in beneficiaries without coverage from 22.8% to 4.0%, 29.1% to 7.3%, and 19.9% to 3.7% among poor, near-poor, and higher-income beneficiaries, respectively. Despite these gains, near-poor status remained a risk factor for lack of prescription drug coverage after the implementation of Medicare Part D (odds ratio, 2.46; 95% CI, 1.26-4.55; P = .04). No differences were identified in adjusted out-of-pocket prescriptions drug costs between the near poor and those with higher income, although out-of-pocket costs were 37% (95% CI, 26%-49%; P < .001) lower among the poor relative to those with higher income. Medicare Part D enrolled most beneficiaries with glaucoma who previously lacked prescription drug coverage. The results of this study suggest that coverage gains lagged among the near poor. While these data evaluated changes in coverage among cohorts of beneficiaries and not from longitudinal follow-up of patients, targeted efforts to improve prescription drug coverage among vulnerable beneficiaries would likely improve access to prescribed ocular hypotensive medications.

Racial/Ethnic Differences in Cost-Related Nonadherence and Medicare Part D: A Longitudinal Comparison

Little is known about whether racial and ethnic disparities in cost-related medication nonadherence (CRN) have changed since the implementation of Medicare Part D. This longitudinal study examined the impact of Part D on CRN among racial and ethnic minority Medicare beneficiaries, age 65 and older. Nationally representative data were obtained from the Prescription Drug Study and Health and Retirement Study. A differences-in-differences approach was used to compare CRN among non-Hispanic Blacks, Hispanics, and non-Hispanic Whites. The results indicate CRN was higher among the two minority groups than among non-Hispanic Whites before and after Medicare Part D. Mixed-effects logistic regression analyses show that CRN did not significantly change between pre- and post-Medicare Part D for any of these three groups. However, older non-Hispanic Blacks and Hispanics had a larger reduction in CRN than non-Hispanic Whites. These findings suggest that despite Medicare Part D, racial and ethnic disparities in CRN persist.

Cost-Related Medication Nonadherence and Cost-Saving Behaviors Among Patients With Glaucoma Before and After the Implementation of Medicare Part D.

Understanding factors that lead to nonadherence to glaucoma treatment is important to diminish glaucoma-related disability. To determine whether the implementation of the Medicare Part D prescription drug benefit affected rates of cost-related nonadherence and cost-reduction strategies in Medicare beneficiaries with and without glaucoma and to evaluate associated risk factors for such nonadherence. Serial cross-sectional study using 2004 to 2009 Medicare Current Beneficiary Survey data linked with Medicare claims. Coding to extract data started in January 2014 and analyses were performed between September and November of 2014. Participants were all Medicare beneficiaries, including those with a glaucoma-related diagnosis in the year prior to the collection of the survey data, those with a nonglaucomatous ophthalmic diagnosis in the year prior to the collection of the survey data, and those without a recent eye care professional claim. Effect of the implementation of the Medicare Part D drug benefit. The change in cost-related nonadherence and the change in cost-reduction strategies. Between 2004 and 2009, the number of Medicare beneficiaries with glaucoma who reported taking smaller doses and skipping doses owing to cost dropped from 9.4% and 8.2% to 2.7% (P < .001) and 2.8%, respectively (P = .001). However, reports of failure to obtain prescriptions owing to cost did not improve in the same period (3.4% in 2004 and 2.1% in 2009; P = .12). After Part D, patients with glaucoma had a decrease in several cost-reduction strategies, namely price shopping (26.2%-15.2%; P < .001), purchasing outside the United States (6.9%-1.3%; P < .001), and spending less money to save for medications (8.0% to 3.5%; P < .001). Using a multivariate analysis, the main independent risk factors common to all cost-related nonadherence measures were female sex, younger age, lower income (<$30 000), self-reported visual disability, and a smaller Lawton index. After the implementation of Part D, there was a decrease in the rate that beneficiaries with glaucoma reported engaging in cost-saving measures. Although there was a decline in the rate of several cost-related nonadherence behaviors, patients reporting failure to fill prescriptions owing to cost remained stable. This suggests that efforts to improve cost-related nonadherence should focus both on financial hardship and medical therapy prioritization, particularly in certain high-risk sociodemographic groups.

Trends in benzodiazepine prescribing under Medicare Part D in USA: outpatient settings 2005-2009

Objectives The objective of the study was to examine the trend of benzodiazepine prescribing under Medicare Part D formulary restriction. Methods A secondary data analysis was conducted using the National Ambulatory Medical Care Survey between 2005 and 2009. Subjects were identified from ambulatory physician office visits where the primary payment source was Medicare and at least one US Food and Drug Administration (FDA)-approved benzodiazepine was prescribed. Data trend were graphically plotted and further analysed using segmented regression. Key findings An estimated 4.9 billion visits to office-based physicians from 2005 to 2009 of which 1.2 billion (24.24%) were made by Medicare recipients. Of these, 86.9 million (7.38%) visits received at least one FDA-approved benzodiazepine including alprazolam (33.3%), lorazepam (24.4%), clonazepam (16.2%), diazepam (12.1%), etc. One year after the passage of Medicare Part D benzodiazepine exclusion, benzodiazepine prescribing decreased 1.83%. However, it had dramatically increased (21.7%) in 2007. Results from segmented regression indicated that implementation of Medicare Part D drug benefits, with benzodiazepine exclusion, is significantly associated with benzodiazepine utilisation (P = 0.015). Conclusion The study findings indicated that benzodiazepine prescribing was not decreased by Medicare Part D formulary exclusion. Several factors could explain this phenomenon: (1) economic perspectives, (2) Medicare supplement programmes, (3) physician prescribing patterns/habits, (4) elderly dependence on benzodiazepines. Despite benzodiazepines having been allowed on Medicare Part D formularies in 2013, this amendment may lead to an even greater importance to healthcare professionals and policy makers by providing comprehensive patient care that ensures optional medication therapy outcomes.

Dear health care lobbyists . . .

Dear health care lobbyists . . .

Adherence and persistence to prescribed medication therapy among Medicare part D beneficiaries on dialysis: comparisons of benefit type and benefit phase.

The implementation of Medicare Part D provided insurance coverage for outpatient medications, but when persons reach the "gap," they have very limited or no medication insurance coverage until they reach a second threshold for catastrophic coverage. In addition, some patients have a low-income subsidy (LIS), and their out-of-pocket costs do not reach the threshold for the gap. Little is known about how these Part D types (LIS versus non-LIS) and benefit phases (before the gap, during the gap, after the gap) affect medication adherence and persistence of dialysis patients. To examine medication use, adherence, and persistence for Medicare-eligible dialysis patients by Part D benefit type and benefit phase. A retrospective cohort study using data from the U.S. Renal Data System (USRDS) was conducted for Medicare-eligible dialysis patients. Outcomes included medication use, adherence, and persistence. Patients were categorized into 4 cohorts based on their Part D benefit phase that the beneficiaries reached at the end of the year and LIS receipt in 2007: Cohort 1 = non-LIS and did not reach the coverage gap; Cohort 2 = non-LIS and reached the coverage gap; Cohort 3 = non-LIS and reached catastrophic coverage after the gap; and Cohort 4 = received an LIS and none of the LIS patients reached the coverage gap. Outcomes were measured separately for 5 therapeutic classes of outpatient prescription drugs: antihyperglycemics, antihypertensives, antilipidemics, phosphate binders, and calcimimetics. A total of 11,732 patients met the study inclusion criteria. Patients were distributed among the cohorts as follows: 3,678 (31.3%) patients in Cohort 1 who did not reach the coverage gap; 4,349 (37.1%) patients in Cohort 2 who reached the coverage gap but not catastrophic coverage; 1,310 (11.2%) patients in Cohort 3 who reached catastrophic coverage; and 2,395 (20.4%) patients in Cohort 4 who had an LIS (none of whom reached the gap). Overall, the percentage of patients who were adherent to their medications (≥ 80% medication possession ratio) was low: 39% for antihyperglycemics, 59% for antihypertensives, 54% for antilipidemics, 22% for phosphate binders, and 35% for cinacalcet. There were wide ranges in adherence rates depending on the cohort. For patients on antihyperglycemics, antihypertensives, antilipidemics, phosphate binders, and cinacalcet, the odds ratios for adherence to therapy were 0.76 (95% C I =0.63-0.92), 1.06 (0.94-1.19), 0.80 (0.67-0.95), 0.65 (0.55-0.76), and 0.39 (0.30-0.49), respectively; the hazard ratios for discontinuation of therapy were 1.18 (95% CI 1.06-1.31), 1.01 (0.93-1.10), 1.25 (1.12-1.40), 1.13 (1.05-1.21), and 1.61 (1.75-1.82), respectively, for Cohort 2 patients who reached the coverage gap compared with those in Cohort 4 who received an LIS. In addition, when comparing adherence before and after the benefit gap, patients in Cohort 2 were significantly more likely to be nonadherent to medications for diabetes (relative risk (RR) = 1.71, 95% CI = 1.48-1.99), hypertension (RR = 1.69, 95% CI = 1.54-1.85), hyperlipidemia (RR = 2.01, 95% CI = 1.76-2.29), hyperphosphatemia (RR = 1.74, 95% CI = 1.55-1.95), and hyperparathyroidism (RR = 2.08, 95% CI = 1.66-2.60) after reaching the coverage gap. More than half of Medicare beneficiaries on dialysis reached the Part D coverage gap in 2007. Our findings suggest that the Part D coverage gap was significantly associated with decreases in adherence and persistence for medications frequently used in patients undergoing dialysis. Patients who reached the coverage gap (Cohort 2) often decreased use of or discontinued critical medications after reaching the coverage gap. Compared with patients who had an LIS (Cohort 4), patients in Cohort 2 had significantly lower medication adherence and persistence levels. The negative impact of the Part D coverage gap (high out-of-pocket cost sharing) on medication adherence and persistence for Medicare-eligible dialysis patients has implications for currently proposed Medicare end-stage renal disease bundled reimbursement payment and requires more research.