How Low-Income Subsidy Recipients Respond to Medicare Part D Cost Sharing

Predictors of adherence to direct oral anticoagulants after cardiovascular or bleeding events in Medicare Advantage Plan enrollees with atrial fibrillation

BACKGROUND

Direct oral anticoagulants (DOACs) are recommended for patients with atrial fibrillation (AF) given their improved safety profile. Suboptimal adherence to DOACs remains a significant concern among individuals with AF. However, the extent of adherence to DOACs following a cardiovascular or bleeding event has not been fully evaluated.

OBJECTIVE

To evaluate the pattern of adherence trajectories of DOACs after a cardiovascular or bleeding event and to investigate the sociodemographic and clinical predictors associated with each adherence trajectory by using claims-based data.

METHODS

This retrospective study was conducted among patients with AF prescribed with DOACs (dabigatran/apixaban/rivaroxaban) between July 2016 and December 2017 and who were continuously enrolled in the Texas-based Medicare Advantage Plan. Patients who experienced a cardiovascular or bleeding event while using the DOACs were further included in the analysis. The sample was limited to patients who experienced a clinical event such as a cardiovascular or bleeding event while using the DOACs. The clinical events considered in this study were cardiovascular (stroke, congestive heart failure, myocardial infarction, systemic embolism) and bleeding events. To assess adherence patterns, each patient with a DOAC prescription was followed up for a year after experiencing a clinical event. The monthly adherence to DOACs after these events was evaluated using the proportion of days covered (PDC). A group-based trajectory model incorporated the monthly PDC to classify groups of patients based on their distinct patterns of adherence. Predictors associated with each trajectory were assessed using a multinomial logistic regression model, with the adherent trajectory serving as the reference group in the outcome variable.

RESULTS

Among the 694 patients with AF who experienced clinical events after the initiation of DOACs, 3 distinct adherence trajectories were identified: intermediate nonadherent (30.50%), adherent (37.7%), and low adherent (31.8%); the mean PDC was 0.47 for the intermediate nonadherent trajectory, 0.93 for the adherent trajectory, and 0.01 for low adherent trajectory. The low-income subsidy was significantly associated with lower adherence trajectories (odds ratio [OR] = 4.81; 95% CI = 3.07-7.51) and with intermediate nonadherent trajectories (OR = 1.57; 95% CI = 1.06-2.34). Also, nonsteroidal anti-inflammatory drug use was significantly associated with lower adherence trajectories (OR = 5.10; 95% CI = 1.95-13.36) and intermediate nonadherent trajectories (OR = 3.17; 95% CI = 1.26-7.93). Other predictors significantly associated with both nonadherent trajectories are type of DOACs (OR = 0.53; 95% CI = 0.35-0.79), presence of coronary artery disease (OR = 1.89; 95% CI = 1.01-3.55), and having 2 or more clinical events (OR = 1.65; 95% CI = 1.09-2.50).

CONCLUSIONS

Predictors identified provide valuable insights into the suboptimal adherence of DOACs among Medicare Advantage Plan enrollees with AF, which can guide the development of targeted interventions to enhance adherence in this high-risk patient population.

Understanding patient and physician responses to various cost-sharing programs for prescription drugs in South Korea: A multilevel analysis

Introduction

Patient and/or physician responses are a pivotal issue in designing rational cost-sharing programs under health insurance systems.

Objectives

This study aims to understand patient and/or physician responses to cost-sharing programs designed for prescription drugs in South Korea.

Methods

As a framework, we took advantage of a tiered cost-sharing program, including from copayment to coinsurance (threshold 1) and reduced coinsurance (threshold 2). Given the hierarchical structure of prescriptions nested within patients, we utilized a multilevel analysis to assess effects of various cost-sharing programs on patient and/or physician responses using National Health Insurance claims data from 2018.

Results

We found that a tiered cost-sharing program was effective in changing the behaviors of patients and/or physicians. Threshold 1 was found to be more effective than threshold 2 in changing their behaviors. At the prescription level, sensitivity to cost-sharing programs was associated with prescribed days of treatment and locations of prescription. In a similar vein, sensitivity to cost-sharing programs was associated with gender and age group of patients.

Conclusion

A simplified cost-sharing program with extended intervals should be considered to rationalize cost-sharing programs. Specifically, a cost-sharing program designed for long-term prescriptions for chronic diseases together with an emphasis on cost transparency is required to better guide price-conscious decisions by patients and/or physicians.

Association Between Medication Adherence and Healthcare Costs Among Patients Receiving the Low-Income Subsidy

OBJECTIVES

Significant literature exists on the effects of medication adherence on reducing healthcare costs, but less is known about the effect of medication adherence among Medicare low-income subsidy (LIS) recipients. This study examined the effects of medication adherence on healthcare costs among LIS recipients with diabetes, hypertension, and/or heart failure.

METHODS

This retrospective study analyzed Medicare claims data (2012-2013) linked to the Area Health Resources Files. Using measures developed by the Pharmacy Quality Alliance, adherence to 11 medication classes was studied among patients with 7 possible combinations of the diseases mentioned. Adherence was measured in 8 categories of proportion of days covered (PDC): ≥95%, 90% to <95%, 85% to <90%, 80% to <85%, 75% to <80%, 50% to <75%, 25% to <50%, and <25%. Annual Medicare costs were compared across adherence categories. A generalized linear model was used to control for patient/community characteristics.

RESULTS

Among patients with only one disease, such as diabetes, patients with the lowest adherence (PDC < 25%) had $3152/year higher Medicare costs than patients with the highest adherence (PDC ≥ 95%; $11 101 vs $7949; P < .05). The adjusted costs among patients with PDC < 25% was $1893 higher than patients with PDC ≥ 95% ($9919 vs $8026; P < .05). Among patients with multiple chronic conditions, patients' adherence to medications for fewer diseases had higher costs.

CONCLUSIONS

Greater medication adherence is associated with lower Medicare costs in the Medicare LIS population. Future policy affecting the LIS program should encourage better medication adherence among patients with chronic diseases.

Effect of Medication Copayment on Adherence and Discontinuation in Medicare Beneficiaries with Type 2 Diabetes: A Retrospective Administrative Claims Database Analysis

INTRODUCTION

Nonadherence to antihyperglycemic agents (AHAs) increases the incidence of morbidity and mortality, as well as healthcare-related costs, in patients with type 2 diabetes (T2D). This study examined the association between medication copayment and adherence and discontinuation among elderly patients with T2D who use generic versus branded AHAs.

METHODS

A retrospective, observational cohort study used Medicare administrative claims data (index period: 1 June 2012 to 31 December 2013). Drug copayments were measured as the copayment of the index medication for a 30-day supply after patients met their plan deductible. Patients were stratified into a branded or generic cohort based on the index medication. Adherence was measured by the proportion of days covered (≥ 80%) and discontinuation by a treatment gap of > 60 days in 10 months during the follow-up period. Poisson regressions were conducted for medication adherence and discontinuation, while controlling for demographic, clinical, and comorbid conditions.

RESULTS

Overall, 160,250 patients on AHA monotherapy were included in the analysis; 131,594 (82%) were prescribed a generic and 28,656 (18%) a branded AHA with a mean copay of $6 and $41, respectively. Increases in copayment increased nonadherence and discontinuation for branded medications but not for generic AHA medications. In both cohorts, elderly patients (≥ 75 years of age) had a lower risk of nonadherence and discontinuation. Black patients had a higher risk of nonadherence or discontinuing medication. Patients having more frequent inpatient, emergency room, and/or physician visits were at higher risk of nonadherence or discontinuing therapy in the branded and generic cohorts (P < 0.001).

CONCLUSION

The impact of drug copayment on adherence and discontinuation varied considerably between branded and generic AHAs. Medicare patients taking branded AHAs had a higher risk of nonadherence with increasing copayment and were more likely to discontinue medication, whereas this association was not observed in patients taking generic medications.

FUNDING

Merck & Co, Inc., Kenilworth, NJ, USA. Plain language summary available for this article.