Impact of Cost-sharing on Utilization of Medications for Secondary Prevention of Cardiovascular Morbidity and Mortality in Medicare Beneficiaries

Persistent Link:
http://hdl.handle.net/10150/203445
Title:
Impact of Cost-sharing on Utilization of Medications for Secondary Prevention of Cardiovascular Morbidity and Mortality in Medicare Beneficiaries
Author:
Olvey, Eleanor
Issue Date:
2011
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Purpose: The purpose of this study was to determine the influence of out-of-pocket prescription and healthcare costs on adherence to guideline recommended statins, angiotensin converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARB), and beta-blockers (BB) used for secondary prevention of coronary heart disease and the associations of adherence with cardiovascular mortality in community-dwelling Medicare beneficiaries ≥ 65 years. Methods: Data from the 2004, 2005, and 2006 Medicare Current Beneficiary Survey (MCBS) was utilized to conduct a retrospective, cross-sectional (i.e., multiple cohort) study. Dependent variables of interest included adherence to statins, ACE/ARBs or BBs, and all-cause mortality, with out-of-pocket (OOP) costs, and adherence to these medications the primary independent variables of interest in these models. Adherence was analyzed as a binary variable with ≥ 80 percent annual adherence the threshold utilized in primary analyses. Total OOP prescription costs for all medications and total OOP healthcare costs borne by the beneficiary were reported. Complex survey design-specified logistic regression with sampling weights was the main statistical analysis used. Sensitivity analyses on adherence thresholds and subgroups were additionally conducted. Results: A significant positive relationship between total OOP prescription costs and statin adherence was identified across observation years in the primary models. Similar relationships were noted for ACE/ARBs and BB in 2004, and ACE/ARBs in 2005. No significant association between adherence and total OOP healthcare costs was indicated in the primary models. Mortality could not be used as a clinical outcome of interest due to limitations with the data. Thus, acute coronary syndrome (ACS) events were used as the clinical outcome. At the ≥ 80 percent threshold, no significant reductions in ACS events were reported. However, various sensitivity analyses did suggest significant reductions in ACS events with ACE/ARBs. Additionally, significantly higher risk of ACS was noted when BB adherence thresholds were reduced to ≥ 60 percent. Conclusions: OOP prescription costs are a significant factor influencing adherence to these medications used for secondary prevention of CAD/MI in Medicare beneficiaries. Continuing to monitor how these costs impact adherence and ultimately outcomes will be critical, particularly given policy changes such as Medicare Part-D.
Type:
text; Electronic Dissertation
Keywords:
Medicare; medications; secondary prevention; Pharmaceutical Sciences; cardiovascular; cost-sharing
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Pharmaceutical Sciences
Degree Grantor:
University of Arizona
Advisor:
Skrepnek, Grant H.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleImpact of Cost-sharing on Utilization of Medications for Secondary Prevention of Cardiovascular Morbidity and Mortality in Medicare Beneficiariesen_US
dc.creatorOlvey, Eleanoren_US
dc.contributor.authorOlvey, Eleanoren_US
dc.date.issued2011-
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractPurpose: The purpose of this study was to determine the influence of out-of-pocket prescription and healthcare costs on adherence to guideline recommended statins, angiotensin converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARB), and beta-blockers (BB) used for secondary prevention of coronary heart disease and the associations of adherence with cardiovascular mortality in community-dwelling Medicare beneficiaries ≥ 65 years. Methods: Data from the 2004, 2005, and 2006 Medicare Current Beneficiary Survey (MCBS) was utilized to conduct a retrospective, cross-sectional (i.e., multiple cohort) study. Dependent variables of interest included adherence to statins, ACE/ARBs or BBs, and all-cause mortality, with out-of-pocket (OOP) costs, and adherence to these medications the primary independent variables of interest in these models. Adherence was analyzed as a binary variable with ≥ 80 percent annual adherence the threshold utilized in primary analyses. Total OOP prescription costs for all medications and total OOP healthcare costs borne by the beneficiary were reported. Complex survey design-specified logistic regression with sampling weights was the main statistical analysis used. Sensitivity analyses on adherence thresholds and subgroups were additionally conducted. Results: A significant positive relationship between total OOP prescription costs and statin adherence was identified across observation years in the primary models. Similar relationships were noted for ACE/ARBs and BB in 2004, and ACE/ARBs in 2005. No significant association between adherence and total OOP healthcare costs was indicated in the primary models. Mortality could not be used as a clinical outcome of interest due to limitations with the data. Thus, acute coronary syndrome (ACS) events were used as the clinical outcome. At the ≥ 80 percent threshold, no significant reductions in ACS events were reported. However, various sensitivity analyses did suggest significant reductions in ACS events with ACE/ARBs. Additionally, significantly higher risk of ACS was noted when BB adherence thresholds were reduced to ≥ 60 percent. Conclusions: OOP prescription costs are a significant factor influencing adherence to these medications used for secondary prevention of CAD/MI in Medicare beneficiaries. Continuing to monitor how these costs impact adherence and ultimately outcomes will be critical, particularly given policy changes such as Medicare Part-D.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectMedicareen_US
dc.subjectmedicationsen_US
dc.subjectsecondary preventionen_US
dc.subjectPharmaceutical Sciencesen_US
dc.subjectcardiovascularen_US
dc.subjectcost-sharingen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplinePharmaceutical Sciencesen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorSkrepnek, Grant H.en_US
dc.contributor.committeememberArmstrong, Edward P.en_US
dc.contributor.committeememberBootman, J. Lyleen_US
dc.contributor.committeememberNolan, Paul E.en_US
dc.contributor.committeememberSherrill, Duaneen_US
dc.contributor.committeememberSkrepnek, Grant H.en_US
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