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Park JS, Kim B, Kim Y, Lee SG, Kim TH. Out-of-pocket costs associated with chronic respiratory diseases in Korean adults. Chron Respir Dis 2024; 21:14799731241233301. [PMID: 38385436 PMCID: PMC10893827 DOI: 10.1177/14799731241233301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 01/22/2024] [Indexed: 02/23/2024] Open
Abstract
OBJECTIVES Chronic respiratory diseases (CRDs) are a burden on both individuals and society. While previous literature has highlighted the clinical burden and total costs of care, it has not addressed patients' direct payments. This study aimed to estimate the incremental healthcare costs associated with patients with CRDs, specifically out-of-pocket (OOP) costs. METHODS We used survey data from the 2019 Korea Health Panel Survey to estimate the total OOP costs of CRDs by comparing the annual hospitalizations, outpatient visits, emergency room visits, and medications of patients with and without CRDs. Generalized linear regression models controlled for differences in other characteristics between groups. RESULTS We identified 222 patients with CRDs, of whom 166 were aged 65 years and older. Compared with the non-CRD group, CRD patients spent more on OOP costs (238.3 USD on average). Incremental costs were driven by outpatient visits and medications, which are subject to a coinsurance of 30% or more and may include items not covered by public insurance. Moreover, CRD patients aged 50-64 years incurred the highest incremental costs. DISCUSSION The financial burden associated with CRDs is significant, and outpatient visits and medications constitute the largest components of OOP spending. Policymakers should introduce appropriate strategies to reduce CRD-associated burdens.
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Affiliation(s)
- Jun Su Park
- Department of Public Health, Graduate School, Yonsei University, Seoul, Republic of Korea
| | - Bomgyeol Kim
- Department of Public Health, Graduate School, Yonsei University, Seoul, Republic of Korea
| | - Yejin Kim
- Department of Public Health, Graduate School, Yonsei University, Seoul, Republic of Korea
| | - Sang Gyu Lee
- Department of Preventive Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Tae Hyun Kim
- Department of Healthcare Management, Graduate School of Public Health, Yonsei University, Seoul, Republic of Korea
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Jiang YX, Zhou LX, Yang LL, Huang QS, Xiao H, Li DW, Zhou YM, Hu YG, Tang EJ, Li YF, Ji AL, Luo P, Cai TJ. The association between short-term exposure to ambient carbon monoxide and hospitalization costs for bronchitis patients: A hospital-based study. ENVIRONMENTAL RESEARCH 2022; 210:112945. [PMID: 35202627 DOI: 10.1016/j.envres.2022.112945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/28/2021] [Accepted: 02/09/2022] [Indexed: 06/14/2023]
Abstract
Ambient carbon monoxide (CO) is associated with bronchitis morbidity, but there is no evidence concerning its correlation with hospitalization costs for bronchitis patients. This study aimed to investigate the relationship between short-term ambient CO exposure and hospitalization costs for bronchitis patients in Chongqing, China. Baseline data for 3162 hospitalized bronchitis patients from November 2013 to December 2019 were collected. Multiple linear regression analysis was used to determine the association, delayed and cumulative, between short-term CO exposure and hospitalization costs. Additionally, subgroup analyses were performed by gender, age, season, and comorbidity. Positive association between CO and hospitalization costs for bronchitis patients was observed. The strongest association was observed at lag 015 days, with per 1 mg/m3 increase of CO concentrations corresponded to 5834.40 Chinese Yuan (CNY) (95% CI: 2318.71, 9350.08; P < 0.001) (845.97 US dollars) increment in hospitalization costs. Stratified analysis results showed that the association was more obvious among those males, elderly, with comorbidities, and in warm seasons. More importantly, there was strongest correlation between CO and bronchitis patients with coronary heart disease. In summary, short-term exposure to ambient CO, even lower than Chinese and WHO standards, can be associated with increased hospitalization costs for bronchitis. Controlling CO exposure can be helpful to reduce medical burden associated with bronchitis patients. The results also suggest that when setting air quality standards and formulating preventive measures, susceptible subpopulations ought to be considered.
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Affiliation(s)
- Yue-Xu Jiang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, China; Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Lai-Xin Zhou
- Medical Department, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, 400037, China
| | - Li-Li Yang
- Department of Information, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, 400037, China
| | - Qing-Song Huang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, China; Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Hua Xiao
- Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Da-Wei Li
- Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Yu-Meng Zhou
- Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Yue-Gu Hu
- Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - En-Jie Tang
- Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Ya-Fei Li
- Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Ai-Ling Ji
- Department of Preventive Medicine, Chongqing Medical and Pharmaceutical College, Chongqing, 401331, China.
| | - Peng Luo
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, China.
| | - Tong-Jian Cai
- Department of Epidemiology, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China.
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MacIntyre AT, Hirst A, Duttagupta R, Hollemon D, Hong DK, Blauwkamp TA. Budget Impact of Microbial Cell-Free DNA Testing Using the Karius ® Test as an Alternative to Invasive Procedures in Immunocompromised Patients with Suspected Invasive Fungal Infections. APPLIED HEALTH ECONOMICS AND HEALTH POLICY 2021; 19:231-241. [PMID: 32944831 PMCID: PMC7497859 DOI: 10.1007/s40258-020-00611-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 09/08/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Invasive fungal infection is a major source of morbidity and mortality. The usage of microbial cell-free DNA for the detection and identification of invasive fungal infection has been considered as a potential alternative to invasive procedures allowing for rapid results. OBJECTIVE This analysis aimed to assess the budget implications of using the Karius® Test in patients suspected of invasive fungal infection in an average state in the USA from a healthcare payer perspective. METHODS The analysis used a decision tree to capture key stages of the patient pathway, from suspected invasive fungal infection to either receiving treatment for invasive fungal infection or being confirmed as having no invasive fungal infection. The analysis used published costs and resource use from a targeted review of the literature. Because of the paucity of published evidence on the reduction of diagnostic tests displaced by the Karius Test, the analysis used a 50% reduction in the use of bronchoscopy and/or bronchoalveolar lavage. The impact of this reduction was tested in a scenario analysis. RESULTS The results of the analysis show that the introduction of the Karius Test is associated with a cost saving of US$2277 per patient; when multiplied by the estimated number of cases per year, the cost saving is US$17,039,666. The scenario analysis showed that the Karius Test only had an incremental cost of US$87 per patient when there was no reduction in bronchoscopy and bronchoalveolar lavage. CONCLUSIONS The Karius Test may offer a valuable and timely option for the diagnosis of invasive fungal infection through its non-invasive approach and subsequent cost savings.
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Affiliation(s)
- Ann T MacIntyre
- Karius, Inc., 975 Island Drive, Suite 101, Redwood City, CA, 94065, USA.
| | | | - Radha Duttagupta
- Karius, Inc., 975 Island Drive, Suite 101, Redwood City, CA, 94065, USA
| | - Desiree Hollemon
- Karius, Inc., 975 Island Drive, Suite 101, Redwood City, CA, 94065, USA
| | - David K Hong
- Karius, Inc., 975 Island Drive, Suite 101, Redwood City, CA, 94065, USA
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4
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Stevens M, Davis T, Munson SH, Shenoy AV, Gricar BLA, Yapici HO, Shaw AD. Short and Mid-Term Economic Impact of Pulmonary Artery Catheter Use in Adult Cardiac Surgery: A Hospital and Integrated Health System Perspective. CLINICOECONOMICS AND OUTCOMES RESEARCH 2021; 13:109-119. [PMID: 33574686 PMCID: PMC7872861 DOI: 10.2147/ceor.s282253] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 12/14/2020] [Indexed: 11/23/2022] Open
Abstract
Objective A monitoring pulmonary artery catheter (PAC) is utilized in approximately 34% of the US cardiac surgical procedures. Increased use of PAC has been reported to have an association with complication rates: significant decreases in new-onset heart failure (HF) and respiratory failure (RF), but increases in bacteremia and urinary tract infections. We assessed the impact of increasing PAC adoption on hospital costs among cardiac surgery patients for US-based healthcare systems. Methods An Excel-based economic model calculated annualized savings for a US hospital with various cardiac surgical volumes and PAC adoption rates. A second model, for an integrated payer-provider health system, analyzed outcomes/costs resulting from the cardiac surgical admission and for the treatment of persistent HF and RF complications in the year following surgery. Model inputs were extracted from published literature, and one-way and probabilistic sensitivity analyses were performed. Results For an acute care hospital with 500 procedures/year and 34% PAC adoption, annualized savings equalled $61,806 vs no PAC utilization. An increase in PAC adoption rate led to increased savings of $134,751 for 75% and $170,685 for 95% adoption. Savings ranged from $12,361 to $185,418 at volumes of 100 and 1500 procedures/year, respectively. For an integrated payer-provider health system with the base-case scenario of 3845 procedures/year and 34% PAC adoption, estimated savings were $596,637 for the combined surgical index admission and treatment for related complications over the following year. Conclusion PAC utilization in adult cardiac surgery patients results in reduced costs for both acute care hospitals and payer-provider integrated health systems.
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Affiliation(s)
- Mitali Stevens
- Global Health Economics & Reimbursement, Edwards Lifesciences, Irvine, CA, USA
| | - Todd Davis
- Global Health Economics & Reimbursement, Edwards Lifesciences, Irvine, CA, USA
| | - Sibyl H Munson
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, MA, USA
| | - Apeksha V Shenoy
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, MA, USA
| | - Boye L A Gricar
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, MA, USA
| | - Halit O Yapici
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, MA, USA
| | - Andrew D Shaw
- Department of Anaesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
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Stevens M, Shenoy AV, Munson SH, Yapici HO, Gricar BLA, Zhang X, Shaw AD. Healthcare utilization and costs of cardiopulmonary complications following cardiac surgery in the United States. PLoS One 2019; 14:e0226750. [PMID: 31856265 PMCID: PMC6922411 DOI: 10.1371/journal.pone.0226750] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 11/26/2019] [Indexed: 11/18/2022] Open
Abstract
PURPOSE This study examined postoperative heart failure (HF) and respiratory failure (RF) complications and related healthcare utilization for one year following cardiac surgery. METHODS This study identified adult patients undergoing isolated coronary artery bypass graft (CABG) and/or valve procedures from the Cerner Health Facts® database. It included patients experiencing postoperative HF or RF complications. We quantified healthcare utilization using the frequency of inpatient admissions, emergency department (ED) visits with or without hospital admission, and outpatient visits. We then determined direct hospital costs from the determined healthcare utilization. We analyzed trends over time for both HF and RF and evaluated the association between surgery type and HF complication. RESULTS Of 10,298 patients with HF complications, 1,714 patients (16.6%) developed persistent HF; of the 10,385 RF patients, 175 (1.7%) developed persistent RF. Healthcare utilization for those with persistent complications over the one-year period following index hospital discharge comprised an average number of the following visit types: Inpatient (1.49 HF; 1.55 RF), Outpatient (2.02, 0.51), ED without hospital admission (0.33, 0.13), ED + Inpatient (0.08, 0.06). Per patient annual costs related to persistent complications of HF and RF were $20,857 and $30,745, respectively. There was a significant association between cardiac surgical type and the incidence of HF, with risk for isolated valve procedures (adjusted OR 2.60; 95% CI: 2.35-2.88) and CABG + valve procedures (adjusted OR 2.38; 95% CI: 2.17-2.61) exceeding risk for isolated CABG procedures. CONCLUSIONS This study demonstrates that HF and RF complication rates post cardiac surgery are substantial, and complication-related healthcare utilization over the first year following surgery results in significant incremental costs. Given the need for both payers and providers to focus on healthcare cost reduction, this study fills an important gap in quantifying the mid-term economic impact of postoperative cardiac surgical complications.
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Affiliation(s)
- Mitali Stevens
- Global Health Economics & Reimbursement, Edwards Lifesciences, Irvine, California, United States of America
| | - Apeksha V. Shenoy
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, Massachusetts, United States of America
| | - Sibyl H. Munson
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, Massachusetts, United States of America
| | - Halit O. Yapici
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, Massachusetts, United States of America
| | - Boye L. A. Gricar
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, Massachusetts, United States of America
| | - Xuan Zhang
- Department of Health Economics and Outcomes Research, Boston Strategic Partners, Inc., Boston, Massachusetts, United States of America
| | - Andrew D. Shaw
- Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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Luo L, Li J, Lian S, Zeng X, Sun L, Li C, Huang D, Zhang W. Using machine learning approaches to predict high-cost chronic obstructive pulmonary disease patients in China. Health Informatics J 2019; 26:1577-1598. [PMID: 31709900 DOI: 10.1177/1460458219881335] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The accurate identification and prediction of high-cost Chronic obstructive pulmonary disease (COPD) patients is important for addressing the economic burden of COPD. The objectives of this study were to use machine learning approaches to identify and predict potential high-cost patients and explore the key variables of the forecasting model, by comparing differences in the predictive performance of different variable sets. Machine learning approaches were used to estimate the medical costs of COPD patients using the Medical Insurance Data of a large city in western China. The prediction models used were logistic regression, random forest (RF), and extreme gradient boosting (XGBoost). All three models had good predictive performance. The XGBoost model outperformed the others. The areas under the ROC curve for Logistic Regression, RF and XGBoost were 0.787, 0.792 and 0.801. The precision and accuracy metrics indicated that the methods achieved correct and reliable results. The results of this study can be used by healthcare data analysts, policy makers, insurers, and healthcare planners to improve the delivery of health services.
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Affiliation(s)
| | | | | | | | | | - Chunyang Li
- West China Hospital of Sichuan University, China
| | - Debin Huang
- Chengdu Medical Insurance Administration, China
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7
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Eskandari M, Nordgren TM, O'Connell GD. Mechanics of pulmonary airways: Linking structure to function through constitutive modeling, biochemistry, and histology. Acta Biomater 2019; 97:513-523. [PMID: 31330329 DOI: 10.1016/j.actbio.2019.07.020] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 07/07/2019] [Accepted: 07/11/2019] [Indexed: 12/24/2022]
Abstract
Breathing involves fluid-solid interactions in the lung; however, the lack of experimental data inhibits combining the mechanics of air flow to airway deformation, challenging the understanding of how biomaterial constituents contribute to tissue response. As such, lung mechanics research is increasingly focused on exploring the relationship between structure and function. To address these needs, we characterize mechanical properties of porcine airways using uniaxial tensile experiments, accounting for bronchial orientation- and location- dependency. Structurally-reinforced constitutive models are developed to incorporate the role of collagen and elastin fibers embedded within the extrafibrillar matrix. The strain-energy function combines a matrix description (evaluating six models: compressible NeoHookean, unconstrained Ogden, uncoupled Mooney-Rivlin, incompressible Ogden, incompressible Demiray and incompressible NeoHookean), superimposed with non-linear fibers (evaluating two models: exponential and polynomial). The best constitutive formulation representative of all bronchial regions is determined based on curve-fit results to experimental data, accounting for uniqueness and sensitivity. Glycosaminoglycan and collagen composition, alongside tissue architecture, indicate fiber form to be primarily responsible for observed airway anisotropy and heterogeneous mechanical behavior. To the authors' best knowledge, this study is the first to formulate a structurally-motivated constitutive model, augmented with biochemical analysis and microstructural observations, to investigate the mechanical function of proximal and distal bronchi. Our systematic pulmonary tissue characterization provides a necessary foundation for understanding pulmonary mechanics; furthermore, these results enable clinical translation through simulations of airway obstruction in disease, fluid-structure interaction insights during breathing, and potentially, predictive capabilities for medical interventions. STATEMENT OF SIGNIFICANCE: The advancement of pulmonary research relies on investigating the biomechanical response of the bronchial tree. Experiments demonstrating the non-linear, heterogeneous, and anisotropic material behavior of porcine airways are used to develop a structural constitutive model representative of proximal and distal bronchial behavior. Calibrated material parameters exhibit regional variation in biomaterial properties, initially hypothesized to originate from tissue constituents. Further exploration through biochemical and histological analysis indicates mechanical function is primarily governed by microstructural form. The results of this study can be directly used in finite element and fluid-structure interaction models to enable physiologically relevant and more accurate computational simulations aimed to help diagnose and monitor pulmonary disease.
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Affiliation(s)
- Mona Eskandari
- Department of Mechanical Engineering, University of California at Riverside, Riverside, CA 92521, USA; Department of Bioengineering, University of California at Riverside, Riverside, CA 92521, USA; BREATHE Center School of Medicine, University of California at Riverside, Riverside, CA 92521, USA; Department of Mechanical Engineering, University of California at Berkeley, Berkeley, CA 94720, USA.
| | - Tara M Nordgren
- Division of Biomedical Sciences, University of California at Riverside, Riverside, CA 92521, USA; BREATHE Center School of Medicine, University of California at Riverside, Riverside, CA 92521, USA
| | - Grace D O'Connell
- Department of Mechanical Engineering, University of California at Berkeley, Berkeley, CA 94720, USA; Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco, CA 94143, USA
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Lakiang T, Nair NS, Ramaswamy A, Singhal U. Economic impact of chronic obstructive pulmonary disease: A cross-sectional study at teaching hospital in South India. J Family Med Prim Care 2019; 7:1002-1006. [PMID: 30598947 PMCID: PMC6259545 DOI: 10.4103/jfmpc.jfmpc_75_16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Background Chronic obstructive pulmonary disease continues to be the important contribution toward disability, death, and burden in the costs of health care globally. Economic impact of COPD is attributed with substantial direct and indirect costs. COPD affects the productivity of work that poses a burden on the employers and also on individuals in terms of loss of pay, limitation of activities, and related disability. Materials and Methods Hospital-based cross-sectional study among 24 respondents in selected hospital in Udupi Taluk. Respondents were identified by purposive sampling technique and data were collected in respondent's mother tongue. An interviewer administered questionnaire was used to collect data related to patient's demographic status, disease history, and direct and indirect costs of COPD. Data were analyzed using SPSS software version 15. Results The mean total direct medical cost that was observed among 24 respondents was Rs. 29,885 ± 11,995.33 and the mean total direct nonmedical cost was Rs. 7,441.25 ± 2,228.90. The mean total direct medical costs of COPD patients with comorbidity were Rs. 28,148.2353 ± 2,578.01580 and for those without comorbid illness was Rs. 13,460.0000 ± 1,255.33528. The observed mean absenteeism in the past 28 days was 193.50 ± 33.62 h. The mean absolute presenteeism of respondents is 72.05 ± 7.55. Conclusions The major drivers of the total cost were cost of hospitalizations and medication costs. Acknowledging the costs and economic impact of COPD is therefore extremely important in the management of COPD and in reducing the mortality and morbidity related to COPD and in improving adherence to treatment.
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Affiliation(s)
- Theophilus Lakiang
- Department of Public Health, Public Health Evidence South Asia, Manipal University, Manipal, Karnataka, India
| | - N Sreekumaran Nair
- Department of Public Health, Public Health Evidence South Asia, Manipal University, Manipal, Karnataka, India
| | - Aarthy Ramaswamy
- Department of Public Health, Public Health Evidence South Asia, Manipal University, Manipal, Karnataka, India
| | - Umang Singhal
- Department of Public Health, Public Health Evidence South Asia, Manipal University, Manipal, Karnataka, India
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Eskandari M, Arvayo AL, Levenston ME. Mechanical properties of the airway tree: heterogeneous and anisotropic pseudoelastic and viscoelastic tissue responses. J Appl Physiol (1985) 2018; 125:878-888. [PMID: 29745796 DOI: 10.1152/japplphysiol.00090.2018] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Airway obstruction and pulmonary mechanics remain understudied despite lung disease being the third cause of death in the United States. Lack of relevant data has led computational pulmonary models to infer mechanical properties from available material data for the trachea. Additionally, the time-dependent, viscoelastic behaviors of airways have been largely overlooked, despite their potential physiological relevance and utility as metrics of tissue remodeling and disease progression. Here, we address the clear need for airway-specific material characterization to inform biophysical studies of the bronchial tree. Specimens from three airway levels (trachea, large bronchi, and small bronchi) and two orientations (axial and circumferential) were prepared from five fresh pig lungs. Uniaxial tensile tests revealed substantial heterogeneity and anisotropy. Overall, the linear pseudoelastic modulus was significantly higher axially than circumferentially (30.5 ± 3.1 vs. 8.4 ± 1.1 kPa) and significantly higher among circumferential samples for small bronchi than for the trachea and large bronchi (12.5 ± 1.9 vs. 6.0 ± 0.6 and 6.6 ± 0.9 kPa). Circumferential samples exhibited greater percent stress relaxation over 300 s than their axial counterparts (38.0 ± 1.4 vs. 23.1 ± 1.5%). Axial and circumferential trachea samples displayed greater percent stress relaxation (26.4 ± 1.6 and 42.5 ± 1.7%) than corresponding large and small bronchi. This ex vivo pseudoelastic and viscoelastic characterization reveals novel anisotropic and heterogeneous behaviors and equips us to construct airway-specific constitutive relations. Our results establish necessary fundamentals for airway mechanics, laying the groundwork for future studies to extend to clinical questions surrounding lung injury, and further directly enables computational tools for lung disease obstruction predictions. NEW & NOTEWORTHY Understanding the mechanics of the lung is necessary for investigating disease progression. Trachea mechanics comprises the vast majority of ex vivo airway tissue characterization despite distal airways being the site of disease manifestation and occlusion. Furthermore, viscoelastic studies are scarce, whereas time-dependent behaviors could be potential physiological metrics of tissue remodeling. In this study, the critical need for airway-specific material properties is addressed, reporting bronchial tree anisotropic and heterogeneous material properties.
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Affiliation(s)
- Mona Eskandari
- Department of Mechanical Engineering, University of California at Riverside , Riverside, California.,Department of Mechanical Engineering, Stanford University , Stanford, California
| | - Alberto L Arvayo
- Department of Mechanical Engineering, Stanford University , Stanford, California
| | - Marc E Levenston
- Department of Mechanical Engineering, Stanford University , Stanford, California.,Department of Bioengineering, Stanford University , Stanford, California
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10
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Chen X, Wang N, Chen Y, Xiao T, Fu C, Xu B. Costs of chronic obstructive pulmonary disease in urban areas of China: a cross-sectional study in four cities. Int J Chron Obstruct Pulmon Dis 2016; 11:2625-2632. [PMID: 27799761 PMCID: PMC5079691 DOI: 10.2147/copd.s118523] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
PURPOSE The economic burden of COPD has not been well studied in China. This study investigated the total costs caused by COPD and the influencing factors for the high economic burden in urban areas of China. PATIENTS AND METHODS A cross-sectional study was carried out among 678 COPD patients in four cities in China in 2011. The average annual direct medical costs (DMCs), direct nonmedical costs (DNMCs), and indirect costs (ICs) on COPD were measured by median and mean (± standard deviation). Logistic regression model was used to explore factors related to high total costs on COPD. RESULTS The median annual DMCs, DNMCs, and ICs per COPD patient were RMB 5565 Yuan (US$ 862), 0 Yuan (US$ 0), and 0 Yuan (US$ 0), respectively, and the mean annual DMCs, DNMCs, and ICs per COPD patient were RMB 11968 (±22422) Yuan [US$ 1853 (±3472)], 539 (±2092) Yuan [US$ 83 (±324)], and 2087 (±8110) Yuan [US$ 323 (±1256)], respectively. The annual DMCs, DNMCs, and ICs for diagnosed COPD patients were RMB 195.70 billion Yuan (US$ 30.30 billion), 8.78 billion Yuan (US$ 1.36 billion), and 34.10 billion Yuan (US$ 5.28 billion), respectively, in China. Hospitalization accounted for 56.7% of the total costs. High economic burden was significantly related to age, acute exacerbations, and disease severity in COPD patients. CONCLUSION COPD posed a heavy economic burden in China. Measures to delay the disease progression and to reduce the risks of acute exacerbation and hospitalization will help substantially lower the costs for COPD care.
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Affiliation(s)
- Xiaoying Chen
- Department of Epidemiology, School of Public Health; Key Laboratory of Public Health Safety, Fudan University, Shanghai, People's Republic of China
| | - Na Wang
- Department of Epidemiology, School of Public Health; Key Laboratory of Public Health Safety, Fudan University, Shanghai, People's Republic of China
| | - Yue Chen
- Department of Epidemiology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Tian Xiao
- Department of Epidemiology, School of Public Health; Key Laboratory of Public Health Safety, Fudan University, Shanghai, People's Republic of China
| | - Chaowei Fu
- Department of Epidemiology, School of Public Health; Key Laboratory of Public Health Safety, Fudan University, Shanghai, People's Republic of China
| | - Biao Xu
- Department of Epidemiology, School of Public Health; Key Laboratory of Public Health Safety, Fudan University, Shanghai, People's Republic of China
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11
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Eskandari M, Javili A, Kuhl E. Elastosis during airway wall remodeling explains multiple co-existing instability patterns. J Theor Biol 2016; 403:209-218. [PMID: 27211101 DOI: 10.1016/j.jtbi.2016.05.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 05/08/2016] [Accepted: 05/16/2016] [Indexed: 01/07/2023]
Abstract
Living structures can undergo morphological changes in response to growth and alterations in microstructural properties in response to remodeling. From a biological perspective, airway wall inflammation and airway elastosis are classical hallmarks of growth and remodeling during chronic lung disease. From a mechanical point of view, growth and remodeling trigger mechanical instabilities that result in inward folding and airway obstruction. While previous analytical and computational studies have focused on identifying the critical parameters at the onset of folding, few have considered the post-buckling behavior. All prior studies assume constant microstructural properties during the folding process; yet, clinical studies now reveal progressive airway elastosis, the degeneration of elastic fibers associated with a gradual stiffening of the inner layer. Here, we explore the influence of temporally evolving material properties on the post-bifurcation behavior of the airway wall. We show that a growing and stiffening inner layer triggers an additional subsequent bifurcation after the first instability occurs. Evolving material stiffnesses provoke failure modes with multiple co-existing wavelengths, associated with the superposition of larger folds evolving on top of the initial smaller folds. This phenomenon is exclusive to material stiffening and conceptually different from the phenomenon of period doubling observed in constant-stiffness growth. Our study suggests that the clinically observed multiple wavelengths in diseased airways are a result of gradual airway wall stiffening. While our evolving material properties are inspired by the clinical phenomenon of airway elastosis, the underlying concept is broadly applicable to other types of remodeling including aneurysm formation or brain folding.
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Affiliation(s)
- Mona Eskandari
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Ali Javili
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA
| | - Ellen Kuhl
- Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94305, USA.
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Patient-Specific Airway Wall Remodeling in Chronic Lung Disease. Ann Biomed Eng 2015; 43:2538-51. [PMID: 25821112 DOI: 10.1007/s10439-015-1306-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Accepted: 03/20/2015] [Indexed: 12/20/2022]
Abstract
Chronic lung disease affects more than a quarter of the adult population; yet, the mechanics of the airways are poorly understood. The pathophysiology of chronic lung disease is commonly characterized by mucosal growth and smooth muscle contraction of the airways, which initiate an inward folding of the mucosal layer and progressive airflow obstruction. Since the degree of obstruction is closely correlated with the number of folds, mucosal folding has been extensively studied in idealized circular cross sections. However, airflow obstruction has never been studied in real airway geometries; the behavior of imperfect, non-cylindrical, continuously branching airways remains unknown. Here we model the effects of chronic lung disease using the nonlinear field theories of mechanics supplemented by the theory of finite growth. We perform finite element analysis of patient-specific Y-branch segments created from magnetic resonance images. We demonstrate that the mucosal folding pattern is insensitive to the specific airway geometry, but that it critically depends on the mucosal and submucosal stiffness, thickness, and loading mechanism. Our results suggests that patient-specific airway models with inherent geometric imperfections are more sensitive to obstruction than idealized circular models. Our models help to explain the pathophysiology of airway obstruction in chronic lung disease and hold promise to improve the diagnostics and treatment of asthma, bronchitis, chronic obstructive pulmonary disease, and respiratory failure.
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Agler AH, Crystal RG, Mezey JG, Fuller J, Gao C, Hansen JG, Cassano PA. Differential expression of vitamin E and selenium-responsive genes by disease severity in chronic obstructive pulmonary disease. COPD 2014; 10:450-8. [PMID: 23875740 DOI: 10.3109/15412555.2012.761958] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Antioxidant nutritional status is hypothesized to influence chronic obstructive pulmonary disease (COPD) susceptibility and progression. Although past studies relate antioxidants to gene expression, there are no data in patients with COPD. This study investigated the hypothesis that antioxidant status is compromised in patients with COPD, and antioxidant-responsive genes differentially express in a similar pattern. Lung tissue samples from patients with COPD were assayed for vitamin E and gene expression. Selenium and vitamin E were assayed in corresponding plasma samples. Discovery based genome-wide expression analysis compared moderate, severe, and very severe COPD (GOLD II-IV) patients to mild and at-risk/normal (GOLD 0-I). Hypotheses-driven analyses assessed differential gene expression by disease severity for vitamin E-responsive and selenium-responsive genes. GOLD II-IV COPD patients had 30% lower lung tissue vitamin E levels compared to GOLD 0-I participants (p = 0.0082). No statistically significant genome-wide differences in expression by disease severity were identified. Hypothesis-driven analyses of 109 genes found 16 genes differentially expressed (padjusted < 0.05) by disease severity including 6 selenium-responsive genes (range in fold-change -1.39 to 2.25), 6 vitamin E-responsive genes (fold-change -2.30 to 1.51), and 4 COPD-associated genes. Lung tissue vitamin E in patients with COPD was associated with disease severity and vitamin E-responsive genes were differentially expressed by disease severity. Although nutritional status is hypothesized to contribute to COPD risk, and is of therapeutic interest, evidence to date is mainly observational. The findings reported herein are novel, and support a role of vitamin E in COPD progression.
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Affiliation(s)
- Anne H Agler
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
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Miravitlles M. Health status and costs of exacerbations of chronic bronchitis and COPD: how to improve antibiotic treatment. Expert Rev Pharmacoecon Outcomes Res 2014; 5:423-35. [DOI: 10.1586/14737167.5.4.423] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Clinical outcomes and cost analysis of exacerbations in chronic obstructive pulmonary disease. Lung 2013; 191:523-30. [PMID: 23842641 DOI: 10.1007/s00408-013-9487-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Accepted: 06/12/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Exacerbations are a major cause of disability, hospital admissions, and increased healthcare costs in patients with chronic obstructive pulmonary disease (COPD). This study investigated the clinical outcomes of outpatients with moderate to severe exacerbated COPD and their related costs. METHODS An observational study on the outcomes of ambulatory exacerbations of COPD was conducted. The course of the exacerbation was evaluated at a follow-up visit at 4 weeks. A cost analysis that encompassed the use of healthcare resources for treatment of the exacerbation was performed. RESULTS A total of 260 patients were included, with a mean age of 68.3 years and a mean FEV1 (% predicted) of 58.9 %. Twenty-two percent of patients had significant cardiovascular comorbidity. The most frequently prescribed antibiotics were moxifloxacin in 137 cases and amoxicillin-clavulanate in 50 cases. The rate of failure at 4 weeks was 12.5 %, with no differences between the two most prescribed antibiotics; however, patients treated with moxifloxacin had symptoms for 1.9 fewer days (P = 0.01). The mean cost of the exacerbation was <euro>344.96 (95 % CI: <euro>48.55-<euro>641.78), with 9.6 % of the costs for drugs and 72.9 % for hospital care of patients for whom treatment had failed. CONCLUSIONS Antibiotic treatment of our population was in compliance with local guidelines. The rate of failure observed in our study was lower than that reported in previous studies; however, the small percentage of patients that required hospital attention generated almost two-thirds of the total costs of the exacerbations.
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Darnell K, Dwivedi AK, Weng Z, Panos RJ. Disproportionate utilization of healthcare resources among veterans with COPD: a retrospective analysis of factors associated with COPD healthcare cost. COST EFFECTIVENESS AND RESOURCE ALLOCATION 2013; 11:13. [PMID: 23763761 PMCID: PMC3700817 DOI: 10.1186/1478-7547-11-13] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 05/24/2013] [Indexed: 11/10/2022] Open
Abstract
Background COPD is a significant cause of morbidity and mortality in the Veterans Health Administration (VHA). To determine the clinical factors associated with the cost of COPD management, we analyzed the relationship between clinical characteristics and COPD healthcare costs at the Cincinnati VAMC. Methods We queried the VHA Decision Support System for patients diagnosed with COPD at the Cincinnati VAMC and calculated their VHA COPD-related encounters and costs in FY2008. Patients were ranked by COPD-related cost. We determined the detailed clinical characteristics of patients selected by modified systematic sampling and performed univariate and multivariable ordinary linear regression analysis to determine factors associated with cost. Results 3263 Veterans had 11,869 encounters with a primary or secondary diagnosis of COPD: 10,032 clinic visits, 505 emergency department (ED) visits, and 1,332 hospitalizations and incurred a total COPD-related healthcare cost of $21.4 M: $2.4 M clinic visits, $0.21 M ED visits, and $18.7 M hospitalizations and $0.89 M for COPD-related prescription costs. When the patients were ranked by VHA healthcare costs, the top 20% of patients accounted for 86% of the total costs and 57% of the total encounters with a primary or secondary diagnosis code of COPD and 90% of the total costs and 75% of the total encounters with a primary diagnosis code of COPD. The clinical characteristics and VHA healthcare costs of 840 of the 3263 unique individuals with COPD were analyzed to determine those characteristics associated with increased COPD-related costs. Univariate analysis showed significant associations with 24 clinical variables; the 4 most highly associated factors were nursing home residence, total hospital admissions, use of oral corticosteroids, and supplemental oxygen (p < 0.001 for all). In multivariate analysis, total number of admissions (p < 0.001), management by a pulmonologist (p < 0.001), number of clinic visits (p < 0.001), use of short acting anticholinergic (p = 0.001), forced expiratory volume in 1 second (FEV1) (p = 0.011), number of prescriptions (p = 0.011), body mass index (BMI) (p = 0.025), and use of inhaled corticosteroid (p = 0.043) were associated with COPD management cost. Conclusion The total number of admissions, clinic visits, physiologic impairment, BMI, number of medications, and type of provider are strongly associated with the total cost of COPD management. These factors may be used to focus COPD management toward patients with the potential for high utilization of healthcare resources.
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Affiliation(s)
- Kyle Darnell
- Pulmonary, Critical Care, and Sleep Medicine Division, Cincinnati Veterans Affairs Medical Center, Cincinnati, OH 45220, USA ; Pulmonary, Critical Care, and Sleep Medicine Division, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Alok Kumar Dwivedi
- Division of Biostatistics and Epidemiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Zhouyang Weng
- Division of Biostatistics and Epidemiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Ralph J Panos
- Pulmonary, Critical Care, and Sleep Medicine Division, Cincinnati Veterans Affairs Medical Center, Cincinnati, OH 45220, USA ; Pulmonary, Critical Care, and Sleep Medicine Division, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
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Lucioni C, Donner CF, De Benedetto F, Lusuardi M, Mazzi S, Paggiaro PL, Sanguinetti CM. I costi della broncopneumopatia cronica ostruttiva in Italia. Presentazione della prima fase dello studio ICE (Italian Costs for Exacerbations in COPD). ACTA ACUST UNITED AC 2013. [DOI: 10.1007/bf03320618] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Chong J, Karner C, Poole P. Tiotropium versus long-acting beta-agonists for stable chronic obstructive pulmonary disease. Cochrane Database Syst Rev 2012; 2012:CD009157. [PMID: 22972134 PMCID: PMC8935978 DOI: 10.1002/14651858.cd009157.pub2] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Tiotropium and long-acting beta(2)-agonists (LABAs) are both accepted in the routine management for people with stable chronic obstructive pulmonary disease (COPD). There are new studies which have compared tiotropium with LABAs, including some that have evaluated recently introduced LABAs. OBJECTIVES To compare the relative clinical effects of tiotropium bromide alone versus LABA alone, upon measures of quality of life, exacerbations, lung function and serious adverse events, in people with stable COPD.To critically appraise and summarise current evidence on the costs and cost-effectiveness associated with tiotropium compared to LABA in people with COPD. SEARCH METHODS We identified randomised controlled trials (RCTs) from the Cochrane Airways Group Specialised Register of trials and economic evaluations from searching NHS EED and HEED (date of last search February 2012). We found additional trials from web-based clinical trial registers. SELECTION CRITERIA We included RCTs and full economic evaluations if they compared effects of tiotropium alone with LABAs alone in people with COPD. We allowed co-administration of standard COPD therapy. DATA COLLECTION AND ANALYSIS Two review authors independently assessed studies for inclusion, then extracted data on study quality and outcomes. We contacted study authors and trial sponsors for additional information. We analysed data using the Cochrane Review Manager(RevMan 5.1) software. MAIN RESULTS Seven clinical studies totalling 12,223 participants with COPD were included in the review. The studies used similar designs and were generally of good methodological quality. Inclusion criteria for RCTs were similar across the included studies, although studies varied in terms of smoking history and COPD severity of participants. They compared tiotropium (which was delivered by HandiHaler in all studies) with salmeterol (four studies, 8936 participants), formoterol (one study, 431 participants) and indacaterol (two studies, 2856 participants). All participants were instructed to discontinue anticholinergic or long-acting beta(2)-agonist bronchodilators during treatment, but could receive inhaled corticosteroids (ICS) at a stable dose. Study duration ranged from 3 to 12 months. We extracted data for 11,223 participants. In general, the treatment groups were well matched at baseline. Overall, the risk of bias across the included RCTs was low.In the analysis of the primary outcomes in this review, a high level of heterogeneity amongst studies meant that we did not pool data for St George's Respiratory Questionnaire quality of life score. Subgroup analyses based on the type of LABA found statistically significant differences among effects on quality of life depending on whether tiotropium was compared with salmeterol, formoterol or indacaterol. Tiotropium reduced the number of participants experiencing one or more exacerbations compared with LABA (odds ratio (OR) 0.86; 95% confidence interval (CI) 0.79 to 0.93). For this outcome, there was no difference seen among the different types of LABA. There was no statistical difference in mortality observed between the treatment groups.For secondary outcomes, tiotropium was associated with a reduction in the number of COPD exacerbations leading to hospitalisation compared with LABA treatment (OR 0.87; 95% 0.77 to 0.99), but not in the overall rate of all-cause hospitalisations. There was no statistically significant difference in forced expiratory volume in one second (FEV(1)) or symptom score between tiotropium and LABA-treated participants. There was a lower rate of non-fatal serious adverse events recorded with tiotropium compared with LABA (OR 0.88; 95% CI 0.78 to 0.99). The tiotropium group was also associated with a lower rate of study withdrawals (OR 0.89; 95% CI 0.81 to 0.99).We identified six full economic evaluations assessing the cost and cost-effectiveness of tiotropium and salmeterol. The studies were based on an economic model or empirical analysis of clinical data from RCTs. They all looked at maintenance costs and the costs for COPD exacerbations, including respiratory medications and hospitalisations. The setting for the evaluations was primary and secondary care in the UK, Greece, Netherlands, Spain and USA. All the studies estimated tiotropium to be superior to salmeterol based on better clinical outcomes (exacerbations or quality of life) and/or lower total costs. However, the authors of all evaluations reported there was substantial uncertainty around the results. AUTHORS' CONCLUSIONS In people with COPD, the evidence is equivocal as to whether or not tiotropium offers greater benefit than LABAs in improving quality of life; however, this is complicated by differences in effect among the LABA types. Tiotropium was more effective than LABAs as a group in preventing COPD exacerbations and disease-related hospitalisations, although there were no statistical differences between groups in overall hospitalisation rates or mortality during the study periods. There were fewer serious adverse events and study withdrawals recorded with tiotropium compared with LABAs. Symptom improvement and changes in lung function were similar between the treatment groups. Given the small number of studies to date, with high levels of heterogeneity among them, one approach may be to give a COPD patient a substantial trial of tiotropium, followed by a LABA (or vice versa), then to continue prescribing the long-acting bronchodilator that the patient prefers. Further studies are needed to compare tiotropium with different LABAs, which are currently ongoing. The available economic evidence indicates that tiotropium may be cost-effective compared with salmeterol in several specific settings, but there is considerable uncertainty around this finding.
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Affiliation(s)
- Jimmy Chong
- University of Auckland, Auckland, New Zealand.
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Rycroft CE, Heyes A, Lanza L, Becker K. Epidemiology of chronic obstructive pulmonary disease: a literature review. Int J Chron Obstruct Pulmon Dis 2012; 7:457-94. [PMID: 22927753 PMCID: PMC3422122 DOI: 10.2147/copd.s32330] [Citation(s) in RCA: 186] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Indexed: 11/23/2022] Open
Abstract
The aim of this study is to quantify the burden of chronic obstructive pulmonary disease (COPD) – incidence, prevalence, and mortality – and identify trends in Australia, Canada, France, Germany, Italy, Japan, The Netherlands, Spain, Sweden, the United Kingdom, and the United States of America. A structured literature search was performed (January 2000 to September 2010) of PubMed and EMBASE, identifying English-language articles reporting COPD prevalence, incidence, or mortality. Of 2838 articles identified, 299 full-text articles were reviewed, and data were extracted from 133 publications. Prevalence data were extracted from 80 articles, incidence data from 15 articles, and mortality data from 58 articles. Prevalence ranged from 0.2%–37%, but varied widely across countries and populations, and by COPD diagnosis and classification methods. Prevalence and incidence were greatest in men and those aged 75 years and older. Mortality ranged from 3–111 deaths per 100,000 population. Mortality increased in the last 30–40 years; more recently, mortality decreased in men in several countries, while increasing or stabilizing in women. Although COPD mortality increased over time, rates declined more recently, likely indicating improvements in COPD management. In many countries, COPD mortality has increased in women but decreased in men. This may be explained by differences in smoking patterns and a greater vulnerability in women to the adverse effects of smoking.
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Affiliation(s)
- Catherine E Rycroft
- Market Access and Outcomes Strategy, RTI Health Solutions, Didsbury, Manchester, United Kingdom.
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20
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Perera PN, Armstrong EP, Sherrill DL, Skrepnek GH. Acute exacerbations of COPD in the United States: inpatient burden and predictors of costs and mortality. COPD 2012; 9:131-41. [PMID: 22409371 DOI: 10.3109/15412555.2011.650239] [Citation(s) in RCA: 146] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a leading cause of hospitalizations in the United States and the major cost driver of COPD. This study determined the national inpatient burden of AECOPD and assessed the association of co-morbidities and hospital characteristics with inpatient costs and mortality. Discharge records from the Agency for Healthcare Research and Quality (AHRQ) Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample for 2006 was utilized. Outcomes of costs and mortality were assessed for AECOPD hospitalizations in cases ≥40 years of age. Multivariate regression analyses using a generalized linear model framework were conducted to determine predictors of inpatient costs and mortality controlling for patient demographics, primary payer, co-morbidity index, length of stay, hospital region, mechanical ventilation, and admission period. Overall, 1,254,703 hospitalizations for AECOPD were observed with mean costs of $9545(±12,700) and total costs of $11.9 billion. In-hospital mortality was 4.3% (N = 53,748). Discharges averaged 70.6 (±11.9) years of age. The majority were female (52.8%) and of white race (83.6% of reported race). Several co-morbidities were significantly associated with both costs and mortality (p < 0.001): acute myocardial infarction; congestive heart failure; cerebrovascular disease; lung cancer; cardiac arrhythmias; pulmonary circulation disorders; and weight loss. Significantly higher costs (p < 0.001) were associated with large and urban hospitals. The importance of co-morbidities in AECOPD is indicated in their association with prognosis and inpatient costs. Future research should determine if better management of these conditions can favorably impact the COPD disease burden.
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Affiliation(s)
- Prasadini N Perera
- The University of Arizona, College of Pharmacy, Center for Health Outcomes and PharmcoEconomic Research, Tucson, Arizona 85721, USA.
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Ozkaya S, Findik S, Atici AG. The costs of hospitalization in patients with acute exacerbation of chronic obstructive pulmonary disease. CLINICOECONOMICS AND OUTCOMES RESEARCH 2011; 3:15-8. [PMID: 21935328 PMCID: PMC3169983 DOI: 10.2147/ceor.s14820] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Indexed: 12/29/2022] Open
Abstract
INTRODUCTION Chronic obstructive pulmonary disease (COPD) is a major public health problem. It imparts a substantial economic burden on individuals and society. Acute exacerbations are the main cause of hospital admissions and hospitalizations in patients with COPD in Turkey. OBJECTIVES We aimed to determine the costs of hospitalization in patients with acute exacerbations of COPD (AECOPD). RESULTS A total of 7832 (1556 women, 6276 men) patients were hospitalized due to acute exacerbations of COPD between 2005-2009 in the Samsun Chest Diseases and Thoracic Surgery Hospital, northern Turkey. The mean age was 64.6 ± 19.8 years old and median length of hospital stay was 14.8 ± 9.5 days. The mean cost per admission was US$718 ± 364. Drug costs accounted for the largest portion (53.5%) of the mean cost, followed by bed cost (19.6%). One hundred seventy-four (2.2%) of the total hospitalized patients with AECOPD died in hospital. CONCLUSION AECOPD continues to have both significant economic burden and high mortality rate.
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Affiliation(s)
- Sevket Ozkaya
- Rize University, Department of Pulmonary Medicine, Rize, Turkey
| | - Serhat Findik
- Ondokuz Mayis University, Department of Pulmonary Medicine, Atakum, Samsun, Turkey
| | - Atilla Guven Atici
- Ondokuz Mayis University, Department of Pulmonary Medicine, Atakum, Samsun, Turkey
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Blanchette CM, Roberts MH, Petersen H, Dalal AA, Mapel DW. Economic burden of chronic bronchitis in the United States: a retrospective case-control study. Int J Chron Obstruct Pulmon Dis 2011; 6:73-81. [PMID: 21311695 PMCID: PMC3034282 DOI: 10.2147/copd.s15882] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Chronic bronchitis (CB) is often misdiagnosed or diagnosed at a later stage of chronic obstructive pulmonary disease (COPD). We examined how this later diagnosis may impact health care costs and utilization during the 12 months prior to and 24 months post initial CB diagnosis. METHODS This retrospective case-control analysis used claims data from a large US database from July 1, 2003 through June 30, 2007. Patients with CB aged 40 years and older were propensity matched (N = 11,674) to patients without evidence of COPD or asthma by demographics, CB diagnosis quarter/year, and comorbidities. Group differences were assessed using Student's t-test and Pearson chi-square test statistics. RESULTS Six months prediagnosis, CB patients had higher frequencies of any hospitalization (9.6%, 6.7%; P < 0.05), emergency department/urgent care visits (13.3%, 6.7%; P < 0.05), and prescriptions (97.3%, 94.1%; P < 0.05). Six months postdiagnosis, CB patients had 5.6 times more hospitalizations (P < 0.05) and 3.1 times more emergency department/urgent care visits (P < 0.05) compared with controls. Mean total costs (US$) for CB patients 12 months prediagnosis were significantly higher than controls (months 12-7: $4212, $3826; P < 0.05; months 6-1: $5289, $4285; P < 0.05). CB patients had higher mean total costs ($8919; P < 0.05) 6 months postdiagnosis. Costs remained $2429 higher for CB patients 19-24 months postdiagnosis (P < 0.05). CONCLUSION Health care costs and utilization among CB patients are increased both prior to diagnosis and during the 2 years postdiagnosis. This study suggests that not accurately diagnosing CB early has a substantial impact on health care costs, and that the economic burden for CB patients remains elevated even after adjustment for comorbidities associated with COPD.
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Affiliation(s)
- Christopher M Blanchette
- Division of Clinical and Outcomes Research, Lovelace Respiratory Research Institute, Kannapolis, NC 28081, USA.
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Nielsen R, Klemmetsby M, Gulsvik A. Economics of COPD: literature review and experiences from field work. CLINICAL RESPIRATORY JOURNAL 2010; 2 Suppl 1:104-10. [PMID: 20298358 DOI: 10.1111/j.1752-699x.2008.00092.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
INTRODUCTION The burden of diseases should be described in terms of costs. The available literature gives imprecise estimates of costs of chronic obstructive pulmonary disease (COPD) in the Nordic populations. Previous studies have methodological weaknesses related to choice of disease criteria, the use of highly selected populations and insufficient specification of the cost process. There are no robust estimates concerning the economics of COPD in Norway. METHODS We have conducted a 1 year follow-up cost of illness study in a general population, recruiting ever-smoking Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 2+ COPD patients and ever-smokers without COPD. We have used diaries to recollect data, and comprehensive questionnaires to cover all costs of COPD. RESULTS The main challenges were the participants' unwillingness to complete diaries, the large amount of information and the logistics related to following up 476 individuals on four occasions during one year. CONCLUSIONS We doubt the effect of diaries. However, we recommend a detailed planning of logistics and to emphasize main cost drivers.
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Affiliation(s)
- R Nielsen
- Department of Thoracic Medicine, Institute of Medicine, University of Bergen, Haukeland University Hospital, Bergen, Norway.
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File TM, Marrie TJ. Burden of community-acquired pneumonia in North American adults. Postgrad Med 2010; 122:130-41. [PMID: 20203464 DOI: 10.3810/pgm.2010.03.2130] [Citation(s) in RCA: 304] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
To determine the burden of community-acquired pneumonia (CAP) affecting adults in North America, a comprehensive literature review was conducted to examine the incidence, morbidity and mortality, etiology, antibiotic resistance, and economic impact of CAP in this population. In the United States, there were approximately 4.2 million ambulatory care visits for pneumonia in 2006. Pneumonia and influenza continue to be a common cause of death in the United States (ranked eighth) and Canada (ranked seventh). In 2005, there were >60,000 deaths due to pneumonia in persons aged>or=15 years in the United States alone. The hospitalization rate for all infectious diseases increased from 1525 hospitalizations per 100 000 persons in 1998 to 1667 per 100 000 persons in 2005. Admission to an intensive care unit was required in 10% to 20% of patients hospitalized with pneumonia. The mean length of stay for pneumonia was >or=5 days and the 30-day rehospitalization rate was as high as 20%. Mortality was highest for CAP patients who were hospitalized; the 30-day mortality rate was as high as 23%. All-cause mortality for CAP patients was as high as 28% within 1 year. Streptococcus pneumoniae continues to be the most frequently identified pathogen associated with CAP, and pneumococcal resistance to antimicrobials may make treatment more difficult. The economic burden associated with CAP remains substantial at >$17 billion annually in the United States. Despite the availability and widespread adherence to recommended treatment guidelines, CAP continues to present a significant burden in adults. Furthermore, given the aging population in North America, clinicians can expect to encounter an increasing number of adult patients with CAP. Given the significance of the disease burden, the potential benefit of pneumococcal vaccination in adults is substantial.
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Affiliation(s)
- Thomas M File
- Department of Internal Medicine, Northeastern Ohio University, College of Medicine, Rootstown, OH, USA.
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Nielsen R, Johannessen A, Benediktsdottir B, Gislason T, Buist AS, Gulsvik A, Sullivan SD, Lee TA. Present and future costs of COPD in Iceland and Norway: results from the BOLD study. Eur Respir J 2009; 34:850-7. [PMID: 19357148 PMCID: PMC3334277 DOI: 10.1183/09031936.00166108] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The Burden of Obstructive Lung Disease (BOLD) initiative provides standardised estimates of the burden of chronic obstructive pulmonary disease (COPD) worldwide. We estimate the current and future economic burden of COPD in Reykjavik, Iceland and Bergen, Norway using data from the BOLD initiative. Data on utilisation of healthcare resources were gathered from the BOLD survey, existing literature and unit costs from national sources. Economic data were applied to a Markov model using transition probabilities derived from Framingham data. Sensitivity analyses were conducted varying unit costs, utilisation and prevalence of disease. The cost of COPD was 478 euro per patient per yr in Iceland and 284 euro per patient per yr in Norway. The estimated cumulative costs of COPD for the population aged > or = 40 yrs, were 130 million euro and 1,539 million euro for the following 10 yrs in Iceland and Norway, respectively. Costs of COPD accounted for 1.2 and 0.7% of healthcare budgets in Iceland and Norway, respectively. Sensitivity analyses showed estimates were most sensitive to changes in exacerbation frequency. COPD has a significant economic burden in both Iceland and Norway and will grow in the future. Interventions aimed at avoiding exacerbations will have the most impact on costs of COPD over the next 20 yrs.
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Affiliation(s)
- R Nielsen
- Section of Thoracic Medicine, Institute of Medicine, University of Bergen, Bergen, Norway.
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Foster TS, Miller JD, Marton JP, Caloyeras JP, Russell MW, Menzin J. Assessment of the Economic Burden of COPD in the U.S.: A Review and Synthesis of the Literature. COPD 2009; 3:211-8. [PMID: 17361502 DOI: 10.1080/15412550601009396] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The costs of chronic obstructive pulmonary disease (COPD) pose a major economic burden to the United States. Studies evaluating COPD costs have generated widely variable estimates; we summarized and critically compared recent estimates of the annual national and per-patient costs of COPD in the U.S. Thirteen articles reporting comprehensive estimates of the direct costs of COPD (costs related to the provision of medical goods and services) were identified from searches of relevant primary literature published since 1995. Few papers reported indirect costs of COPD (lost work and productivity). The National Heart, Lung, and Blood Institute (NHLBI) provides the single current estimate of the total (direct plus indirect) annual cost of COPD to the U.S., $38.8 billion in 2005 dollars. More than half of this cost ($21.8 billion) was direct, aligning with the $20-26 billion range reported by two other recent analyses of large national datasets. For per-patient direct costs (in $US 2005), studies using recent data yield attributable cost estimates (costs deemed to be related to COPD) in the range of $2,700-$5,900 annually, and excess cost estimates (total costs incurred by COPD patients minus total costs incurred by non-COPD patients) in the range of $6,100-$6,600 annually. Studies of both national and per-patient costs that use data approximately 8-10 years old or older have produced estimates that tend to deviate from these ranges. Cost-of-illness studies using recent data underscore the substantial current cost burden of COPD in the U.S.
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Affiliation(s)
- Talia S Foster
- Boston Health Economics, Inc., 20 Fox Road, Waltham, MA 02451, USA.
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Menadue C, Piper AJ, van't Hul AJ, Wong KK. Non-invasive ventilation during exercise training for people with chronic obstructive pulmonary disease. THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS 2009. [DOI: 10.1002/14651858.cd007714] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Menzin J, Boulanger L, Marton J, Guadagno L, Dastani H, Dirani R, Phillips A, Shah H. The economic burden of chronic obstructive pulmonary disease (COPD) in a U.S. Medicare population. Respir Med 2008; 102:1248-56. [DOI: 10.1016/j.rmed.2008.04.009] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2007] [Revised: 03/31/2008] [Accepted: 04/06/2008] [Indexed: 11/28/2022]
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Ghanei M, Alikhani S, Adibi I, Mir Mohamm M, Ramazani T, Aslani J. Early Onset Emphysema in Smokers with Additional Exposure to Toxic Fumes; Occurrence and Diagnosis. JOURNAL OF MEDICAL SCIENCES 2008. [DOI: 10.3923/jms.2008.222.227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Kunik ME, Veazey C, Cully JA, Souchek J, Graham DP, Hopko D, Carter R, Sharafkhaneh A, Goepfert EJ, Wray N, Stanley MA. COPD education and cognitive behavioral therapy group treatment for clinically significant symptoms of depression and anxiety in COPD patients: a randomized controlled trial. Psychol Med 2008; 38:385-396. [PMID: 17922939 DOI: 10.1017/s0033291707001687] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Chronic obstructive pulmonary disease (COPD) affects 14 to 20 million Americans and is associated with increased prevalence of affective disorders, contributing significantly to disability. This study compared cognitive behavioral therapy (CBT) group treatment for anxiety and depression with COPD education for COPD patients with moderate-to-severe anxiety and/or depressive symptoms. METHOD A randomized controlled trial (RCT) was conducted between 11 July 2002 and 30 April 2005 at the Michael E. DeBakey VA Medical Center, Houston, TX. Participants were 238 patients treated for COPD the year before, with forced expiratory value in 1 second (FEV)1/forced vital capacity (FVC)<70% and FEV1<70% predicted, and symptoms of moderate anxiety and/or moderate depression, who were being treated by a primary care provider or pulmonologist. Participants attended eight sessions of CBT or COPD education. Assessments were at baseline, at 4 and 8 weeks, and 4, 8 and 12 months. Primary outcomes were disease-specific and generic quality of life (QoL) [Chronic Respiratory Questionnaire (CRQ) and Medical Outcomes Survey Short Form-36 (SF-36) respectively]. Secondary outcomes were anxiety [Beck Anxiety Inventory (BAI)], depressive symptoms [Beck Depression Inventory-II (BDI-II)], 6-minute walk distance (6MWD) and use of health services. RESULTS Both treatments significantly improved QoL, anxiety and depression (p<0.005) over 8 weeks; the rate of change did not differ between groups. Improvements were maintained with no significant change during follow-up. Ratios of post- to pretreatment use of health services were equal to 1 for both groups. CONCLUSIONS CBT group treatment and COPD education can achieve sustainable improvements in QoL for COPD patients experiencing moderate-to-severe symptoms of depression or anxiety.
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Affiliation(s)
- M E Kunik
- Houston Center for Quality of Care and Utilization Studies, Health Services Research and Development Service, Houston, TX 77030, USA.
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One hundred years of respiratory medicine chronic obstructive pulmonary disease (COPD)—Republished article. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.rmedu.2007.11.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Koleva D, Motterlini N, Banfi P, Garattini L. Healthcare costs of COPD in Italian referral centres: A prospective study. Respir Med 2007; 101:2312-20. [PMID: 17681461 DOI: 10.1016/j.rmed.2007.06.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Revised: 06/18/2007] [Accepted: 06/20/2007] [Indexed: 11/30/2022]
Abstract
BACKGROUND This study estimated the healthcare resource utilisation and costs of chronic obstructive pulmonary disease (COPD) patients, staged by severity, in the Italian pneumology departments (PDs). METHODS The project was a multi-centre observational study conducted in 11 Italian PDs throughout the country. A total of 268 patients were recruited and followed prospectively for 1 year. For the purpose of analysis, patients were divided into four groups according to the severity at onset: mild COPD (stage I)-postbronchodilator FEV1/FVC <70% and FEV1 >or=80% of predicted; moderate COPD (stage II)-postbronchodilator FEV1/FVC <70% and 50% <or=FEV1< 80% of predicted; severe COPD (stage III)-postbronchodilator FEV1/FVC <70% and 30% <or=FEV1 <50% of predicted; very severe COPD (stage IV)-postbronchodilator FEV1/FVC <70% and FEV1 <30% of predicted, or clinical signs of either respiratory or cardiac failure. RESULTS Subgroups differed significantly in the main demographic and clinical variables. Broadly, higher severity was associated with older age, longer disease duration, and more frequent exacerbations. Patients with severe COPD used more resources for almost all services than those with mild and moderate forms. The annual average cost per patient was 3040.2 euros (1046.7 euros for mild, 2319.0 euros for moderate, 3572.1 euros for severe and 5033.3 euros for very severe forms). CONCLUSIONS This study offers some information on the healthcare costs of COPD induced by PDs in Italy, potentially useful for decision-making in the health care services. Resources and costs rose significantly with disease severity.
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Affiliation(s)
- Daniela Koleva
- CESAV, Centre for Health Economics, Mario Negri Institute for Pharmacological Research, Villa Camozzi-Via Camozzi, 3 24020 Ranica (Bg), Italy
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Abstract
BACKGROUND Chronic obstructive pulmonary disease (COPD) is a common multi-component disease that imposes an enormous burden on the patient, the healthcare professional and the society in terms of morbidity, mortality, healthcare resource utilisation and cost. Despite the availability of several comprehensive treatment guidelines, COPD is both under-diagnosed and misdiagnosed. Some of the factors contributing to this are a poor knowledge and low adherence to guideline recommendations, on the part of some healthcare professionals, and a lack of understanding of the significance and severity of the disease, on the part of patients. However, evidence suggests that COPD is both preventable and treatable when it is diagnosed early and treated effectively. Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines suggest that the key to early diagnosis is the recognition of the clinical features of persistent cough, chronic sputum production, breathlessness on exertion and a history of exposure to tobacco smoke. Primary care clinicians can play a crucial role in early diagnosis of at-risk subjects. They can educate patients to recognise the early symptoms of COPD, avoid the risk factors, such as smoking, and encourage early presentation to a primary care professional. Similarly, evidence suggests that effective implementation of non-pharmacological and pharmacological interventions can improve the management of COPD patients at the primary care level. OBJECTIVES The aim of this review is to discuss the role of the primary care team in the early diagnosis and effective management of COPD, and to outline education initiatives and management strategies that can be implemented in primary care.
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Affiliation(s)
- D Bellamy
- Bournemouth and Poole PCT, Bournemouth, UK.
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Abstract
OBJECTIVE To evaluate and compare the cost-effectiveness of long-acting bronchodilators by estimating incremental costs per quality-adjusted life-year (QALY) gained in patients with moderate to severe chronic obstructive pulmonary disease. METHODS This cost-effective analysis was conducted from a third-party payer's perspective. The study was a retrospective pooled analysis, and the effectiveness evidence was derived from a systematic review of literature published from January 1, 1980, to April 14, 2006. Incremental QALYs were estimated by converting the St George's Respiratory Questionnaire scores into EuroQoL-5D scores and using these combined scores as the summary benefit measure. RESULTS The incremental cost per additional QALY was $26,094 (range, $11,780-$77,214) for tiotropium and $41,000 (range, $23,650-$98,750) for salmeterol compared with placebo. The cost per QALY gained was lower with tiotropium compared with salmeterol or ipratropium based on either the pooled data of available trials or a head-to-head trial. Treatment with tiotropium could save $391 per year while gaining 13 quality-adjusted days compared with ipratropium. CONCLUSION Tiotropium appears to be more cost-effective than the alternatives and may be the preferred agent for maintenance therapy in patients with moderate to severe chronic obstructive pulmonary disease. Compared with ipratropium, tiotropium could be cost saving. Because of the wide ranges of cost-effectiveness ratios for tiotropium and salmeterol and the significant overlap between them, a large prospective head-to-head trial would help address the uncertainty and confirm the results of this analysis.
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Affiliation(s)
- Yugi Oba
- Department of Pulmonary, Critical Care and Environmental Medicine, University of Missouri-Columbia, Columbia, MO 65212, USA.
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Abstract
Chronic obstructive pulmonary disease (COPD) is an increasing health problem and one of the leading causes of morbidity and mortality worldwide, but knowledge about its pathogenesis has increased substantially in recent years. The disease results from interaction between individual risk factors (like enzymatic deficiencies) and environmental exposures to noxious agents, like cigarette smoking, occupational dusts, air pollution and infections in childhood. The main mechanisms that may contribute to airflow limitation in COPD are fixed narrowing of small airways, emphysema and luminal obstruction with mucus secretions. COPD is characterised by a chronic inflammatory process in the pulmonary tissue, with a pattern different from bronchial asthma, associated with extrapulmonary effects and is considered now a complex, systemic disease. Optimal therapeutic targeting of COPD depends on a clear understanding of the precise mechanisms of these complex processes and on early and correct evaluation of disease severity. A combination of pharmacological and non-pharmacological approaches is used to treat COPD. Bronchodilators are the mainstay of COPD treatment and can be combined with inhaled corticosteroids for greater efficacy and fewer side effects. The use of LTOT for hypoxemic patients has resulted in increased survival, and expanded drug therapy options have effectively improved dyspnoea and quality of life. Recent studies have documented the benefits of pulmonary rehabilitation. In addition, non-invasive mechanical ventilation offers new alternatives for patients with acute or chronic failure.
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Affiliation(s)
- Mario Cazzola
- Department of Internal Medicine, Unit of Respiratory Diseases, University of Rome Tor Vergata, Rome, Italy.
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Miller JD, Foster T, Boulanger L, Chace M, Russell MW, Marton JP, Menzin J. Direct costs of COPD in the U.S.: an analysis of Medical Expenditure Panel Survey (MEPS) data. COPD 2007; 2:311-8. [PMID: 17146996 DOI: 10.1080/15412550500218221] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) is a costly cause of morbidity and mortality in the U.S. The objective of this study was to use contemporary national data-specifically, those from the 2000 Medical Expenditure Panel Survey (MEPS)-to estimate direct costs of COPD in the U.S. from an all-payer perspective. Due to constraints of MEPS data, indirect costs were excluded from our analyses, as were costs of long-term oxygen therapy and costs from nursing homes and long-term care facilities. Two methods of cost estimation were employed. First, we estimated resources used and expenditures incurred by individuals with COPD that were directly attributable to the disease (attributable cost approach). Second, we compared overall medical expenditures of patients with COPD to those of the non-COPD population; the resulting difference represented excess costs of COPD. Approximately 1.7% (n = 144) of the nearly 8,300 persons in the analysis data set aged > or = 45 years used medical resources and incurred expenditures related to treatment of COPD. Mean attributable costs per patient were estimated at dollar 2,507, with more than one-half of these costs (dollar 1,365) associated with hospitalization. Mean excess costs of COPD, after adjustment for sociodemographic factors and smoking status, were substantially higher, at dollar 4,932 per patient. Results of our study indicate that COPD-associated healthcare utilization and expenditures are considerable, and that annual per-patient costs of COPD are comparable to those of other chronic diseases of the middle-aged and elderly.
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Affiliation(s)
- Jeffrey D Miller
- Boston Health Economics, Inc., 20 Fox Road, Waltham, Massachusetts 02451, USA.
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Marton JP, Boulanger L, Friedman M, Dixon D, Wilson J, Menzin J. Assessing the costs of chronic obstructive pulmonary disease: The state medicaid perspective. Respir Med 2006; 100:996-1005. [PMID: 16288858 DOI: 10.1016/j.rmed.2005.10.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2004] [Revised: 08/03/2005] [Accepted: 10/03/2005] [Indexed: 11/26/2022]
Abstract
BACKGROUND State Medicaid programs provide insurance coverage to over 40 million Americans. However, estimates of the annual cost of chronic obstructive pulmonary disease (COPD) from the Medicaid perspective are lacking. METHODS This retrospective cohort study used Medicaid administrative claims data from California and Florida to estimate COPD expenditures using two alternative methods: (1) excess costs (comparing a COPD cohort to a matched comparison cohort); and (2) attributable costs (COPD-related expenditures within a COPD cohort, inclusive of respiratory medications). The COPD cohort in each state included Medicaid recipients not dually eligible for Medicare who were 40+ years of age with at least one medical claim for COPD during 2001. The comparison cohort consisted of patients with medical claims during 2001 for conditions other than chronic respiratory disease, matched by age, sex, and race to the COPD cohort. RESULTS A total of 6,738 Medicaid recipients in California and 18,017 in Florida were included in the COPD cohort, with mean ages of 56 and 60 years, respectively. Comorbidities, especially congestive heart failure and vascular disease, were more common in the COPD cohort than among matched controls. The mean excess cost of COPD per-patient was estimated to be approximately 6,500 US dollars in California Medicaid and 5,200 US dollars in Florida Medicaid. Mean attributable costs of COPD were similar in the two Medicaid programs (approximately 2,200 US dollars and 2,300 US dollars per patient, respectively). CONCLUSIONS COPD places a substantial financial burden on State Medicaid programs. These findings may be of interest to clinicians and policy-makers involved in preventing or managing this chronic disease.
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Roche N, Kouassi B, Rabbat A, Mounedji A, Lorut C, Huchon G. Yield of Sputum Microbiological Examination in Patients Hospitalized for Exacerbations of Chronic Obstructive Pulmonary Disease with Purulent Sputum. Respiration 2006; 74:19-25. [PMID: 16675894 DOI: 10.1159/000093158] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Accepted: 02/20/2006] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Whether sputum microbiological examination should be performed systematically in hospitalized patients with chronic obstructive pulmonary disease (COPD) exacerbations remains unclear. OBJECTIVES To assess the yield of sputum microbiological examination in COPD patients hospitalized in a medical ward for an acute exacerbation with purulent sputum. METHODS Two hundred consecutive exacerbations in 118 patients were studied. Patients underwent sputum microbiological examination on admission and baseline lung function tests and CT scans were recorded. Factors associated with positive culture were analyzed. RESULTS Sputum culture was positive (>or=10(7) CFU/ml) in 59% of samples, Haemophilus influenzae and Streptococcus pneumoniae being the most frequent pathogens. Factors associated with positive culture were bronchiectasis, long-term oxygen therapy and low FEV1. Pseudomonas spp. were found in 8.5% of all patients, who all had a FEV1<50% of predicted and were older. Only 25% of sputum samples satisfied all quality criteria. Sputum culture was positive in a high proportion of these samples (80.5%), but also in one half of samples with >25 leukocytes but >10 epithelial cells per field. Microbiological results induced a change in antibiotic therapy in 43.9% of cases with both quality criteria but also in 25.2% of cases with only one quality criterion. Finally, a predominant aspect after Gram stain was found in all positive samples. CONCLUSIONS These data suggest that sputum microbiological examination with direct examination and leukocyte count should be performed routinely in patients hospitalized for COPD exacerbations with purulent sputum, especially when FEV1 is less than 50% predicted and in patients with bronchiectasis.
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Affiliation(s)
- N Roche
- Service de Pneumologie et Réanimation, Hôpital de l'Hôtel-Dieu, Université Paris 5, Paris, France.
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Faulkner MA, Lenz TL, Stading JA. Cost-effectiveness of smoking cessation and the implications for COPD. Int J Chron Obstruct Pulmon Dis 2006; 1:279-87. [PMID: 18046865 PMCID: PMC2707159 DOI: 10.2147/copd.2006.1.3.279] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The cost burden of COPD is substantial for patients and families, payers, and society as a whole. Smoking has been known for decades to be the leading cause of the disease. Numerous studies have been completed to address the cost-effectiveness of programs created to aid smokers in their efforts to quit. Because several assumptions must be made in order to conduct such a study, and because differences in study design are numerous, comparison of data is difficult. However, studies have consistently shown that regardless of the perspective from which the study was completed, or the methods used to help smokers abstain, the interventions are cost-effective. Although no study has been conducted specifically to assess the cost-effectiveness of smoking cessation interventions as they relate directly to patients with COPD, based on current data it can be concluded that smoking cessation programs are cost-effective for this population.
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Affiliation(s)
- Michele A Faulkner
- Creighton University School of Pharmacy and Health Professions, 2500 California Plaza, Omaha, NE 68178, USA.
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Molina París J, Molina París C, de Lucas Ramos P, Lobo Alvarez MA, Calvo Corbella E, Lumbreras García G. [Effectiveness of a recuperative primary care intervention in patients with chronic obstructive pulmonary disease]. Aten Primaria 2005; 36:39-44. [PMID: 15946614 PMCID: PMC7676125 DOI: 10.1157/13075930] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2004] [Accepted: 11/10/2004] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVES The main objective is to assess the effect of a respiratory rehabilitation programme on the quality of life of patients with COPD. Secondary aims are to determine whether the intervention, as against the habitual monitoring, improves tolerance to exercise and pulmonary function, and reduces dyspnoea, the number of crises and hospital admissions due to COPD and the medication used to control the disease. DESIGN Pragmatic cluster-randomised clinical trial. SETTING Clinics of 16 PC teams in various health areas of the Community of Madrid. PARTICIPANTS 476 patients with light-moderate COPD, who sign their informed consent. VARIABLES Quality of life, number of crises, packages of medicines used to control the disease, unscheduled attendance, pulmonary function, dyspnoea and tolerance to exercise. METHOD The consultations will be assigned to the control and intervention groups at random. At each clinic there will be a randomised selection from all patients with COPD and in a stable clinical condition. 238 patients are needed in each group, in order to detect a minimum difference of 4 points in quality of life, assuming a standard deviation of 16, 95% confidence level, 80% power and 20% losses. The effect between each factor and the variables evaluated through multivariate analysis will be calculated. DISCUSSION This research project aims to show that a basic recuperative intervention, which is feasible and primary care-based, can achieve improvements in the quality of life of patients with COPD.
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Vergnenègre A, Chouaïd C. Le poids économique des BPCO dans les sociétés industrialisées devient de plus en plus important. Rev Mal Respir 2005. [DOI: 10.1016/s0761-8425(05)73067-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
OBJECTIVE The Global Initiative for Obstructive Lung Disease highlights the importance of COPD from public health, health policy and clinical perspectives. In countries such as the USA, the economic impact of COPD exceeds that of many chronic conditions. There is a paucity of data on the economic burden of COPD in Japan. METHODOLOGY Based upon publicly available information, a prevalence-based approach was used to construct a deterministic model to estimate the total direct and indirect costs of care for COPD in Japan. Data sources included a spirometry-based epidemiological study, the peer-reviewed literature, and governmental and industrial surveys. The most current data that addressed direct and indirect costs of care were utilized. RESULTS In Japan, the estimated total cost of COPD is 805.5 billion yen (US 6.8 billion dollars) per year; 645.1 billion yen (US 5.5 billion dollars) in direct costs and 160.4 billion yen (US 1.4 billion dollars) in indirect costs. In direct costs, inpatient care accounted for 244.1 billion yen (US 2.1 billion dollars), outpatient care 299.3 billion yen (US 2.5 billion dollars), and home oxygen therapy 101.7 billion yen (US 0.9 billion dollars). The average annual total cost per patient for moderate/severe COPD is estimated to be 435,876 yen (US 3694 dollars); 349,080 yen (US 2958 dollars) per COPD patient in direct costs and 86,797 yen (US 795 dollars) in indirect costs. CONCLUSION COPD imposes a high economic burden on the Japanese healthcare system. Health policy makers should direct urgent attention to increasing prevention, early diagnosis, and appropriate treatment of COPD.
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Abstract
Hyperpolarized gases belong to a new class of MR contrast agents that, when inhaled, provide high temporal and spatial resolution images of the lung airspaces. At this time, hyperpolarized gas MRI is only being performed at a limited number of institutions. However, the availability of hyperpolarized gas MRI could increase dramatically in coming years as regulatory hurdles within the U.S. are surmounted. The intent of this paper is to provide an introduction to hyperpolarized gas MRI for the thoracic radiologist. It includes a description of the basic principles of hyperpolarized gas MRI and a review of the results of preliminary clinical investigations with this method.
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Affiliation(s)
- Talissa A Altes
- Department of Radiology, University of Virginia, Charlottesville, VA 22908, USA.
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Abstract
Chronic obstructive pulmonary disease (COPD) is a highly prevalent condition that represents a significant economic burden to society. Early diagnosis of COPD offers the best opportunity to slow the progression of the disease through smoking cessation. Aggressive medical management of COPD for patients diagnosed at a moderate or severe stage is likely to be attractive from an economic standpoint, although prospective studies are needed to validate current evidence. Poor adherence to smoking cessation and pharmacologic therapy suggests that patient education is critical to successful intervention at all stages of illness. The economic value of aggressive pharmacotherapy for early-stage COPD is less certain, but the burden of illness and potential pharmacoeconomic benefits in such patients is a strong rationale for combined clinical and economic trials.
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Affiliation(s)
- Scott D Ramsey
- Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
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Miravitlles M. Avaliação econômica da doença pulmonar obstrutiva crônica e de suas agudizações: aplicação na América Latina. J Bras Pneumol 2004. [DOI: 10.1590/s1806-37132004000300015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A doença pulmonar obstrutiva crônica tem elevada prevalência em todo o mundo. Estima-se que entre 7% e 10% da população adulta seja afetada. No Brasil, a bronquite crônica tem uma prevalência de 12,7% na população de mais de 40 anos. Os estudos econômicos têm grande relevância em doenças de alta prevalência. A maioria dos estudos relacionados aos custos da doença pulmonar obstrutiva crônica provém de bases de dados nacionais de saúde. Poucos estudos avaliaram os custos sanitários diretos da doença. A partir destes, conclui-se que um paciente portador de doença pulmonar obstrutiva crônica gera um custo direto anual de 1.200 a 1.800 dólares. O custo correlaciona-se com a gravidade da doença: os pacientes graves geram um custo duas vezes maior que os menos graves, e por isso é vital o diagnóstico precoce. A estratégia mais custo-efetiva é a detecção precoce da doença, associada a campanhas contra o tabagismo. Em estágios avançados da doença, a hospitalização é responsável pelos custos mais elevados. Neste caso, o tratamento correto das agudizações é crucial como estratégia custo-efetiva. O custo médio de uma internação no Brasil é de 2.761 reais, o que representa quase o valor do tratamento ambulatorial por um ano. A antibioticoterapia é responsável por pequena parte do custo total da agudização. O uso de antibióticos mais eficazes pode ser uma estratégia custo-efetiva por reduzir a taxa de fracasso de tratamento. A análise econômica deve permitir a identificação e aplicação de estratégias custo-efetivas para o tratamento da doença.
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Masa JF, Sobradillo V, Villasante C, Jiménez-Ruiz CA, Fernández-Fau L, Viejo JL, Miravitlles M. [Costs of chronic obstructive pulmonary disease in Spain. Estimation from a population-based study]. Arch Bronconeumol 2004; 40:72-9. [PMID: 14746730 DOI: 10.1016/s1579-2129(06)60198-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE In the studies carried out to date, the cost of chronic obstructive pulmonary disease (COPD) may have been overestimated due to the inclusion of previously diagnosed patients seeking medical attention for their symptoms. As a result, the severity of the cases included in these studies may have been greater than in an unselected sample of the general population. The aim of the present study was to estimate the direct cost of COPD on the basis of a representative sample of the overall Spanish population between 40 and 69 years of age (from the IBERPOC study). METHOD The cost was evaluated retrospectively by means of a questionnaire completed by the 363 patients with COPD from the IBERPOC study with questions referring to the previous year. Standardized spirometry was performed on all the patients by a pneumologist in each of the 7 geographical areas in which the study was carried out. RESULTS Hospitalization accounted for the greatest expenditure (41% of total), followed by drug therapy (37%). The cost was euro;98.39 per patient, and euro;909.50 per previously diagnosed patient. The cost per person of severe COPD was more than 3 times that of moderate COPD and more than 7 times that of mild COPD. The estimated annual cost of COPD in Spain was euro;238.82 million (for 1997). CONCLUSION The present study, which was the first to estimate the cost of COPD in a representative sample of the general population, found the cost to be lower than in studies analyzing samples of patients with previous diagnoses of COPD. The cost distribution is not in line with recommended health care practices, underlining the need to optimize resources used to monitor and treat the disease, with an emphasis on early diagnosis.
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Affiliation(s)
- J F Masa
- Sección de Neumología. Hospital San Pedro de Alcántara. Cáceres. España
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Friedman M, Menjoge SS, Anton SF, Kesten S. Healthcare costs with tiotropium plus usual care versus usual care alone following 1 year of treatment in patients with chronic obstructive pulmonary disorder (COPD). PHARMACOECONOMICS 2004; 22:741-749. [PMID: 15250751 DOI: 10.2165/00019053-200422110-00004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
BACKGROUND Healthcare costs for chronic obstructive pulmonary disease (COPD) have continued to increase with the increasing prevalence of the disease. New interventions that can reduce the medical costs of COPD are needed. Tiotropium bromide, a once-daily inhaled anticholinergic, has been evaluated in patients with COPD enrolled in two 1-year randomised, double-blind, placebo-controlled (usual care) trials which showed the drug reduced exacerbations and improved spirometry, dyspnoea, and health status. OBJECTIVE To retrospectively assess the direct costs of medical care for COPD in a US healthcare setting for patients treated with tiotropium in addition to usual care compared with usual care alone over a 1-year timeframe. The study was based on resource utilisation in the two previously described trials. METHODS Resource utilisation and clinical data were prospectively collected for the two 1-year, randomised, double-blind trials of tiotropium plus usual care versus usual care alone (placebo) in 921 patients with COPD. Usual care was defined as any medication for COPD used prior to the trial except anticholinergics and long-acting beta-adrenoceptor agonists. Medical care resource utilisation was recorded at every scheduled visit in each trial. Mean total costs were calculated retrospectively by combining the resources utilised with the appropriate unit costs (1999 US dollars), excluding study drug (tiotropium) costs. RESULTS Compared with usual care, patients receiving tiotropium in addition to usual care had significantly fewer COPD exacerbations (20% decrease), hospitalisations (44% reduction) and hospital days (50% reduction). Utilisation of resources other than hospitalisation did not differ between study groups. As a consequence, patients receiving tiotropium had significantly lower mean per- patient costs of hospitalisation compared with patients receiving usual care alone (tiotropium US 1,738 dollars +/- US 259 dollars; placebo US 2,793 dollars +/- US 453 dollars). The mean difference in the cost of hospitalisation (resulting from all causes, including COPD) between treatment groups was -US 1,056 dollars (95% CI -US 2,078 dollars, -US 34 dollars), and the difference in total healthcare costs (excluding study drug acquisition cost) was -US 1,043 dollars (95% CI -US 2,136 dollars, US 48 dollars) in favour of tiotropium. The cost of hospital admissions accounted for 48% of the total direct medical costs in this trial. CONCLUSIONS As hospitalisation is a large contributor to the cost of COPD, the addition of tiotropium to usual care therapy may have the potential to reduce the economic burden of COPD in a US healthcare setting. However, as our study did not consider the acquisition cost of tiotropium, further economic evaluation including this cost is needed to address whether tiotropium is cost saving compared with usual care (placebo).
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Affiliation(s)
- Mitchell Friedman
- Tulane University Health Sciences Center, New Orleans, Louisiana, USA
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Masa J, Sobradillo V, Villasante C, Jiménez-Ruiz C, Fernández-Fau L, Viejo J, Miravitlles M. Costes de la EPOC en España. Estimación a partir de un estudio epidemiológico poblacional. Arch Bronconeumol 2004. [DOI: 10.1016/s0300-2896(04)75476-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Abstract
COPD is a progressive disorder that is punctuated in its later stages with acute exacerbations that present a risk for respiratory failure. COPD has a disproportionate impact on older patients. In the ICU, therapy is directed toward unloading fatigued respiratory muscles, treating airway infection, and prescribing bronchodilatory drugs. Most patients survive hospitalization in the ICU for an episode of respiratory failure. The severity of the underlying lung disease, however, underlies the poor outcomes of patients in terms of postdischarge survival and quality of life.
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Affiliation(s)
- John E Heffner
- Pulmonary Divison, 812 CSB, Medical University of South Carolina, 96 Jonathan Lucas Street, P.O. Box 250623, Charleston, SC 29425, USA.
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