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Vauterin D, Van Vaerenbergh F, Vanoverschelde A, Quint JK, Verhamme K, Lahousse L. Methods to assess COPD medications adherence in healthcare databases: a systematic review. Eur Respir Rev 2023; 32:230103. [PMID: 37758274 PMCID: PMC10523153 DOI: 10.1183/16000617.0103-2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 07/20/2023] [Indexed: 09/30/2023] Open
Abstract
BACKGROUND The Global Initiative for Chronic Obstructive Lung Disease 2023 report recommends medication adherence assessment in COPD as an action item. Healthcare databases provide opportunities for objective assessments; however, multiple methods exist. We aimed to systematically review the literature to describe existing methods to assess adherence in COPD in healthcare databases and to evaluate the reporting of influencing variables. METHOD We searched MEDLINE, Web of Science and Embase for peer-reviewed articles evaluating adherence to COPD medication in electronic databases, written in English, published up to 11 October 2022 (PROSPERO identifier CRD42022363449). Two reviewers independently conducted screening for inclusion and performed data extraction. Methods to assess initiation (dispensing of medication after prescribing), implementation (extent of use over a specific time period) and/or persistence (time from initiation to discontinuation) were listed descriptively. Each included study was evaluated for reporting variables with an impact on adherence assessment: inpatient stays, drug substitution, dose switching and early refills. RESULTS 160 studies were included, of which four assessed initiation, 135 implementation and 45 persistence. Overall, one method was used to measure initiation, 43 methods for implementation and seven methods for persistence. Most of the included implementation studies reported medication possession ratio, proportion of days covered and/or an alteration of these methods. Only 11% of the included studies mentioned the potential impact of the evaluated variables. CONCLUSION Variations in adherence assessment methods are common. Attention to transparency, reporting of variables with an impact on adherence assessment and rationale for choosing an adherence cut-off or treatment gap is recommended.
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Affiliation(s)
- Delphine Vauterin
- Department of Bioanalysis, Pharmaceutical Care Unit, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Frauke Van Vaerenbergh
- Department of Bioanalysis, Pharmaceutical Care Unit, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Anna Vanoverschelde
- Department of Bioanalysis, Pharmaceutical Care Unit, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Jennifer K Quint
- School of Public Health and National Heart and Lung Institute, Imperial College London, London, UK
| | - Katia Verhamme
- Department of Bioanalysis, Pharmaceutical Care Unit, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
- Department of Medical Informatics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Lies Lahousse
- Department of Bioanalysis, Pharmaceutical Care Unit, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
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Bell CF, Coutinho AD, Farrelly E, Lokhandwala T, Landsman-Blumberg P. Clinical and economic outcomes associated with the use of fluticasone propionate 250 mcg and salmeterol 50 mcg combination versus tiotropium bromide 18 mcg as initial maintenance treatment for chronic obstructive pulmonary disease in managed care. J Med Econ 2018; 21:629-638. [PMID: 29577787 DOI: 10.1080/13696998.2018.1457532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
AIMS To examine the clinical and economic outcomes associated with the use of long-acting bronchodilators for initial maintenance treatment of chronic obstructive pulmonary disease (COPD) by analyzing health insurance claims data in the US. METHODS A retrospective, observational, matched cohort study used health insurance claims data (January 2008 to June 2013) to assess COPD-related outcomes for subjects aged ≥40 years. Subjects were assigned to a study cohort according to the first observed prescription fill for a long-acting bronchodilator (fluticasone propionate 250 mcg/salmeterol 50 mcg [FSC] or tiotropium bromide 18 mcg [TIO]). The analysis period for each subject comprised a 1-year pre-index date and 1-year post-index date. Primary outcome measure was total COPD-related costs per-patient per-year (PPPY) during the follow-up period. Secondary outcome measures included COPD-related exacerbations and the components of COPD-related costs. RESULTS Overall, 24,040 subjects were identified; the analysis sample consisted of 19,090 subjects (9,545 per cohort) with no significant differences between cohorts. Mean COPD-related total costs PPPY were numerically lower among the FSC cohort; however, the difference was not statistically significant ($2,224 [±4,108] vs $2,352 [±3,721], p = .057). There was no difference between cohorts for COPD-related medical costs (p = .894). COPD-related pharmacy costs were significantly, yet modestly, lower in the FSC cohort compared with the TIO cohort ($1,160 [±1,106] vs 1,275 [±1,110], p < .001). There were no statistically significant differences in the rate or number of exacerbations between the matched cohorts. LIMITATIONS While propensity scoring achieved balance in baseline characteristics, some residual confounding unobserved in the database may be present. CONCLUSIONS Few clinical and economic differences between subjects initiating maintenance therapy with FSC or TIO were observed.
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Stephenson JJ, Wertz D, Gu T, Patel J, Dalal AA. Clinical and economic burden of dyspnea and other COPD symptoms in a managed care setting. Int J Chron Obstruct Pulmon Dis 2017; 12:1947-1959. [PMID: 28740375 PMCID: PMC5503502 DOI: 10.2147/copd.s134618] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE The degree to which symptoms such as dyspnea affect patients with COPD is individualized. To address the gap between clinical symptom measures and self-perceived disease burden, we investigated the symptom status of adult patients with COPD and followed with an administrative claims analysis of health care resource utilization and costs. METHODS This was a hybrid US observational study consisting of a cross-sectional patient survey followed by a retrospective analysis of administrative claims data. The primary COPD symptom measures were the modified Medical Research Council (mMRC) Dyspnea scale and the COPD Assessment Test (CAT). RESULTS A total of 673 patients completed the survey. Of these, 65% reported mMRC grades 0-1 (low symptomatology) and 35% reported mMRC grades 2-4 (high symptomatology); 25% reported CAT score <10 (low symptomatology) and 75% reported CAT score ≥10 (high symptomatology). More patients with high symptomatology (by either measure) had at least one COPD-related inpatient hospitalization, emergency room visit, physician office visit, or other outpatient services, and filled at least one COPD-related prescription medication vs patients with low symptomatology. COPD-related costs were higher for patients with high symptomatology than patients with low symptomatology. In a multivariate analysis, COPD-related costs were also higher in patients reporting severe symptoms. CONCLUSION Patients with high COPD symptomatology utilized more health care resources and had higher COPD-related health care costs during the 6-month post-survey period than patients with low symptomatology.
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Affiliation(s)
| | | | - Tao Gu
- HealthCore, Inc., Wilmington, DE
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Mapel D, Laliberté F, Roberts MH, Sama SR, Sundaresan D, Pilon D, Lefebvre P, Duh MS, Patel J. A retrospective study to assess clinical characteristics and time to initiation of open-triple therapy among patients with chronic obstructive pulmonary disease, newly established on long-acting mono- or combination therapy. Int J Chron Obstruct Pulmon Dis 2017; 12:1825-1836. [PMID: 28684905 PMCID: PMC5485896 DOI: 10.2147/copd.s129007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION An incremental approach using open-triple therapy may improve outcomes in patients with chronic obstructive pulmonary disease (COPD). However, there is little sufficient, real-world evidence available identifying time to open-triple initiation. METHODS This retrospective study of patients with COPD, newly initiated on long-acting muscarinic antagonist (LAMA) monotherapy or inhaled corticosteroid/long-acting β2-agonist (ICS/LABA) combination therapy, assessed baseline demographics, clinical characteristics, and exacerbations during 12 months prior to first LAMA or ICS/LABA use. Time to initiation of open-triple therapy was assessed for 12 months post-index date. Post hoc analyses were performed to assess the subsets of patients with pulmonary-function test (PFT) information and patients with and without comorbid asthma. RESULTS Demographics and clinical characteristics were similar between cohorts in the pre-specified and post hoc analyses. In total, 283 (19.3%) and 160 (10.9%) patients had moderate and severe exacerbations at baseline, respectively, in the LAMA cohort, compared with 482 (21.3%) and 289 (12.8%) patients in the ICS/LABA cohort. Significantly more patients initiated open-triple therapy in the LAMA cohort compared with the ICS/LABA cohort (226 [15.4%] versus 174 [7.7%]; P<0.001); results were similar in the post hoc analyses. Mean (standard deviation) time to open-triple therapy was 79.8 (89.0) days in the LAMA cohort and 122.9 (105.4) days in the ICS/LABA cohort (P<0.001). This trend was also observed in the post hoc analyses, though the difference between cohorts was nonsignificant in the subset of patients with PFT information. DISCUSSION In this population, patients with COPD are more likely to initiate open-triple therapy following LAMA therapy, compared with ICS/LABA therapy. Further research is required to identify factors associated with the need for treatment augmentation among patients with COPD.
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Affiliation(s)
- Douglas Mapel
- Health Services Research Division, Lovelace Clinic Foundation, Albuquerque, NM, USA
| | | | - Melissa H Roberts
- Health Services Research Division, Lovelace Clinic Foundation, Albuquerque, NM, USA.,Department of Pharmacy Practice and Administrative Sciences, University of New Mexico, College of Pharmacy, University of New Mexico, Albuquerque, NM
| | - Susan R Sama
- Research Department, Reliant Medical Group, Worcester, MA
| | | | | | | | | | - Jeetvan Patel
- US Health Outcomes, GlaxoSmithKline, Research Triangle Park, NC, USA
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Trudo F, Kern DM, Davis JR, Tunceli O, Zhou S, Graham EL, Strange C, Williams SA. Comparative effectiveness of budesonide/formoterol combination and tiotropium bromide among COPD patients new to these controller treatments. Int J Chron Obstruct Pulmon Dis 2015; 10:2055-66. [PMID: 26451101 PMCID: PMC4592033 DOI: 10.2147/copd.s90658] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Background Inhaled corticosteroid/long-acting β2-agonist combinations and/or long-acting muscarinic antagonists are recommended first-line therapies for preventing chronic obstructive pulmonary disease (COPD) exacerbation. Comparative effectiveness of budesonide/formoterol combination (BFC, an inhaled corticosteroid/long-acting β2-agonist combination) vs tiotropium (long-acting muscarinic antagonist) in the US has not yet been studied. Methods Using US claims data from the HealthCore Integrated Research Environment, COPD patients (with or without comorbid asthma) ≥40 years old initiating BFC or tiotropium between March 1, 2009 and February 28, 2012 and at risk for exacerbation were identified and followed for 12 months. Patients were propensity score matched on demographics and COPD disease severity indicators. The primary outcome was time to first COPD exacerbation. Secondary outcomes included COPD exacerbation rate, health care resource utilization, and costs. Results The Cox proportional hazards model for time to first exacerbation yielded a hazard ratio (HR) of 0.78 (95% CI =[0.70, 0.87], P<0.001), indicating a 22% reduction in risk of COPD exacerbation associated with initiation of BFC versus tiotropium. A post hoc sensitivity analysis found similar effects in those who had a prior asthma diagnosis (HR =0.72 [0.61, 0.86]) and those who did not (HR =0.83 [0.72, 0.96]). BFC initiation was associated with lower COPD-related health care resource utilization and costs ($4,084 per patient-year compared with $5,656 for tiotropium patients, P<0.001). Conclusion In COPD patients new to controller therapies, initiating treatment with BFC was associated with improvements in health and economic outcomes compared with tiotropium.
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Affiliation(s)
- Frank Trudo
- AstraZeneca Pharmaceuticals LP, Wilmington, DE, USA
| | | | - Jill R Davis
- AstraZeneca Pharmaceuticals LP, Wilmington, DE, USA
| | | | | | - Emma L Graham
- AstraZeneca Pharmaceuticals LP, Alderley Park, Cheshire, UK
| | - Charlie Strange
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA
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Mapel DW, Roberts MH. Management of asthma and chronic obstructive pulmonary disease with combination inhaled corticosteroids and long-acting β-agonists: a review of comparative effectiveness research. Drugs 2015; 74:737-55. [PMID: 24797158 PMCID: PMC4030099 DOI: 10.1007/s40265-014-0214-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The value of combination therapy with inhaled corticosteroids and long-acting β-agonists (ICS/LABA) is well recognized in the management of asthma and chronic obstructive pulmonary disease (COPD). Despite differences in the pharmacological properties between two well-established ICS/LABA products (budesonide/formoterol and fluticasone/salmeterol), data from randomized clinical trials (RCTs) and meta-analyses suggest that these two products perform similarly under RCT conditions. In contrast, a few recently reported real-world comparative effectiveness studies have suggested that there are substantial differences between ICS/LABA combination treatments in terms of clinical and healthcare outcomes in patients with asthma or COPD. The purpose of this article is to provide a brief review of the benefits, as well as the limitations, of comparative effectiveness research (CER) in the therapeutic area of asthma and COPD. We conducted a structured literature review of the current CER studies on ICS/LABA combinations in asthma and COPD. These articles were then used to illustrate the unique challenges of CER studies, providing a summary of study results and limitations. We focus particularly on difficult biases and confounding factors that may be introduced before, during, and after the initiation of therapy. Beyond being a review of these two ICS/LABA combination treatments, this article is intended to help those who wish to assess the quality of CER published projects in asthma and COPD, or guide investigators who wish to design new CER studies for chronic respiratory disease treatments.
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Affiliation(s)
- Douglas W Mapel
- Lovelace Clinic Foundation, 2309 Renard Place SE, Albuquerque, NM, 87106, USA,
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Kern DM, Williams SA, Tunceli O, Wessman C, Zhou S, Pethick N, Elhefni H, Trudo F. A US database study characterizing patients initiating a budesonide-formoterol combination versus tiotropium bromide as initial maintenance therapy for chronic obstructive pulmonary disease. Int J Chron Obstruct Pulmon Dis 2014; 9:775-83. [PMID: 25071369 PMCID: PMC4111649 DOI: 10.2147/copd.s64491] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
OBJECTIVE To compare clinical and demographic characteristics, resource utilization and costs of chronic obstructive pulmonary disease (COPD) patients prior to initiating budesonide-formoterol combination (BFC) or tiotropium-maintenance therapy. MATERIALS AND METHODS This cross-sectional study used claims-based diagnosis to identify COPD patients in the HealthCore Integrated Research Database who initiated BFC or tiotropium therapy between March 1, 2009 and January 31, 2012 (intake period); the index date was defined as the initial prescription fill for either agent. Patients diagnosed with respiratory tract cancer or receiving inhaled corticosteroids/long-acting β2-adrenergic agonists or tiotropium in 12 months prior to index date were excluded. Categorical variables were evaluated with χ(2) tests; mean cost differences were evaluated using γ-regression. RESULTS Overall, 6,940 BFC and 10,831 tiotropium patients were identified. The BFC group was younger (mean age 64 versus 67 years), with a greater proportion of females (54% versus 51%). BFC-treated patients had more comorbid respiratory conditions, including asthma (25% versus 13%), but fewer comorbid cardiovascular conditions, including atherosclerosis (7% versus 10%) and myocardial infarction (4% versus 6%). A greater proportion of BFC patients received prior respiratory medication, including oral corticosteroids (46% versus 35%) and short-acting β2-agonists (44% versus 35%). Tiotropium-treated patients had a greater mean number of COPD-related outpatient visits (4.6 versus 4.1). BFC-treated patients had lower total all-cause ($17,259 versus $17,926) and COPD-related ($1,718 versus $1,930) health care costs, driven by lower all-cause and COPD-related inpatient expenditures. CONCLUSION Initiators of BFC or tiotropium showed differences in clinical and demographic characteristics and health care utilization and costs prior to starting COPD maintenance therapy.
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Abstract
The elderly patient (65 years and older) with chronic obstructive pulmonary disease (COPD) can be a challenge to the clinician. This begins with the correct and early diagnosis, the assessment of disease severity, recognizing complicating comorbidities, determining the burden of symptoms, and monitoring the frequency of acute exacerbations. Comprehensive management of COPD in the elderly patient should improve health-related quality of life, lung function, reduce exacerbations, and promote patient compliance with treatment plans. Only smoking cessation and oxygen therapy in COPD patients with hypoxemia reduce mortality. Bronchodilators, corticosteroids, methylxanthines, phosphodiesterase-4 inhibitors, macrolide antibiotics, mucolytics, and pulmonary rehabilitation improve some outcome measures such as spirometry measures and the frequency of COPD exacerbations without improving mortality. International treatment guidelines to reduce symptoms and reduce the risk of acute exacerbations exist. Relief of dyspnea and control of anxiety are important. The approach to each patient is best individualized. Earlier use of palliative care should be considered when traditional pharmacotherapy fails to achieve outcome measures and before consideration of end-of-life issues.
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Dalal AA, Shah M, D’Souza AO, Crater GD. Rehospitalization risks and outcomes in COPD patients receiving maintenance pharmacotherapy. Respir Med 2012; 106:829-37. [DOI: 10.1016/j.rmed.2011.11.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 11/11/2011] [Accepted: 11/16/2011] [Indexed: 12/27/2022]
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Rutten-van Mölken MPMH, Goossens LMA. Cost effectiveness of pharmacological maintenance treatment for chronic obstructive pulmonary disease: a review of the evidence and methodological issues. PHARMACOECONOMICS 2012; 30:271-302. [PMID: 22409290 DOI: 10.2165/11589270-000000000-00000] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
BACKGROUND Over 200 million people have chronic obstructive pulmonary disease (COPD) worldwide. The number of disease-year equivalents and deaths attributable to COPD are high. Guidelines for the pharmacological treatment of the disease recommend an individualized step-up approach in which treatment is intensified when results are unsatisfactory. OBJECTIVE Our objective was to present a systematic review of the cost effectiveness of pharmacological maintenance treatment for COPD and to discuss the methodological strengths and weaknesses of the studies. METHODS A systematic literature search for economic evaluations of drug therapy in COPD was performed in MEDLINE, EMBASE, the Economic Evaluation Database of the UK NHS (NHS-EED) and the European Network of Health Economic Evaluation Databases (EURONHEED). Full economic evaluations presenting both costs and health outcomes were included. RESULTS A total of 40 studies were included in the review. Of these, 16 were linked to a clinical trial, 14 used Markov models, eight were based on observational data and two used a different approach. The few studies on combining short-acting bronchodilators were consistent in finding net cost savings compared with monotherapy. Studies comparing inhaled corticosteroids (ICS) with placebo or no maintenance treatment reported inconsistent results. Studies comparing fluticasone with salmeterol consistently found salmeterol to be more cost effective. The cost-effectiveness studies of tiotropium versus placebo, ipratropium or salmeterol pointed towards a reduction in total COPD-related healthcare costs for tiotropium in many but not all studies. All of these studies reported additional health benefits of tiotropium. The cost-effectiveness studies of the combination of inhaled long-acting β₂-agonists and ICS all report additional health benefits at an increase in total COPD-related costs in most studies. The cost-per-QALY estimates of this combination treatment vary widely and are very sensitive to the assumptions on mortality benefit and time horizon. CONCLUSIONS The currently available economic evaluations indicate differences in cost effectiveness between COPD maintenance therapies, but for a more meaningful comparison of results it is important to improve the consistency with respect to study methodology and choice of comparator.
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Affiliation(s)
- Maureen P M H Rutten-van Mölken
- Institute for Medical Technology Assessment/Institute for Healthcare Policy and Management, Erasmus University Rotterdam, Rotterdam, the Netherlands.
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Roberts MH, Dalal AA. Clinical and economic outcomes in an observational study of COPD maintenance therapies: multivariable regression versus propensity score matching. Int J Chron Obstruct Pulmon Dis 2012; 7:221-33. [PMID: 22500122 PMCID: PMC3324998 DOI: 10.2147/copd.s27569] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To investigate equivalency of results from multivariable regression (MR) and propensity score matching (PSM) models, observational research methods used to mitigate bias stemming from non-randomization (and consequently unbalanced groups at baseline), using, as an example, a large study of chronic obstructive pulmonary disease (COPD) initial maintenance therapy. METHODS Patients were 32,338 health plan members, age ≥40 years, with COPD initially treated with fluticasone propionate/salmeterol combination (FSC), tiotropium (TIO), or ipratropium (IPR) alone or in combination with albuterol. Using MR and PSM methods, the proportion of patients with COPD-related health care utilization, mean costs, odds ratios (ORs), and incidence rate ratios (IRRs) for utilization events were calculated for the 12 months following therapy initiation. RESULTS Of 12,595 FSC, 9126 TIO, and 10,617 IPR patients meeting MR inclusion criteria, 89.1% (8135) of TIO and 80.2% (8514) of IPR patients were matched to FSC patients for the PSM analysis. Methods produced substantially similar findings for mean cost comparisons, ORs, and IRRs for most utilization events. In contrast to MR, for TIO compared to FSC, PSM did not produce statistically significant ORs for hospitalization or outpatient visit with antibiotic or significant IRRs for hospitalization or outpatient visit with oral corticosteroid. As in the MR analysis, compared to FSC, ORs and IRRs for all other utilization events, as well as mean costs, were less favorable for IPR and TIO. CONCLUSION In this example of an observational study of maintenance therapy for COPD, more than 80% of the original treatment groups used in the MR analysis were matched to comparison treatment groups for the PSM analysis. While some sample size was lost in the PSM analysis, results from both methods were similar in direction and statistical significance, suggesting that MR and PSM were equivalent methods for mitigating bias.
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