Journal of General Internal Medicine

, Volume 33, Issue 9, pp 1528–1535 | Cite as

The Impact of Care Specialty on Survival-Adjusted Medical Costs of COPD Patients After a Hospitalization: a longitudinal analysis

  • Wenjia Chen
  • Don D. Sin
  • J. Mark FitzGerald
  • Mohsen Sadatsafavi
  • for the Canadian Respiratory Research Network
Original Research



Little is known about the impact of care provider’s specialty on the medical costs of COPD patients over time.


To compare the long-term medical costs between newly hospitalized COPD patients whose post-discharge care was initiated by a pulmonary specialist versus by a general practitioner.


Retrospective matched cohort study.


We identified patients with an incident COPD-related hospitalization from the administrative health database (January 1, 1996, to December 31, 2012) of British Columbia, Canada.

Main measures

Patients were categorized as receiving specialist care or primary care within the first 90 days after discharge from an incident COPD-related hospitalization. Using propensity scores, we matched each patient who initially received specialist care to a patient who received primary care based on demographics, COPD severity, comorbidity, and admission time. A survival-adjusted, multi-part generalized linear model was used to estimate direct medical costs (in 2015 Canadian dollars, [$], including inpatient, outpatient, pharmacy, and community care costs) as overall and as COPD-specific and comorbidity-related costs over the following 5 years.

Key results

The sample included 7710 patients under each group. The initial specialist-care recipients had a modestly higher 5-year survival than the generalist-care recipients (0.564 [95% CI 0.535, 0.634] vs 0.555 [95% CI 0.525, 0.625]; P < .001). Meanwhile, the former incurred $2809 higher all-cause medical costs over 5 years compared to the latter (95% CI $2343, $2913; P < .001), mainly driven by higher medication costs (difference $1782 [95% CI $1658, $1830]; P < .001) particularly related to COPD medications ($1170 [95% CI $1043, $1225]; P < .001). Specialist care recipients also incurred higher costs of COPD-related hospitalization ($1144 [95% CI $650, $1221]; P < .001).


Compared to generalist care, specialist care following COPD hospitalization is slightly more expensive, mainly driven by medication costs especially COPD-specific medications. Future studies should compare differences in health-related quality of life and COPD functional status.


COPD specialty of care healthcare costs longitudinal analysis 



WC had full access to all of the data in the study and takes responsibility for the content of the manuscript, including the integrity of the data and the accuracy of the data analysis. WC, JMF, DS, and MS conceived and designed the study. WC analyzed the data and wrote the first draft of the manuscript. WC, JMF, DS, and MS contributed to the interpretation of the data and clinical inputs. All authors were involved in the revision of the manuscript for important intellectual content and approved the final version to be published.

Funding sources

This study was funded by the Canadian Respiratory Research Network (CRRN). CRRN is supported by grants from the Canadian Institutes of Health Research (CIHR)-Institute of Circulatory and Respiratory Health, Canadian Lung Association (CLA)/Canadian Thoracic Society (CTS), British Columbia Lung Association, and Industry Partners Boehringer-Ingelheim Canada Ltd, AstraZeneca Canada Inc., and Novartis Canada Ltd. Funding for training of postdoctoral student and new investigators within the network was supported by the above funding Sponsors and as well by GlaxoSmithKline Inc. The funders had no role in the study design, data collection and analysis, or preparation of the manuscript. Dr. Sadatsafavi receives salary support from Michael Smith Foundation for Health Research and Canadian Institutes of Health Research.

Compliance with ethical standards

Conflict of interest

The authors declare no conflict of interests.

Supplementary material

11606_2018_4406_MOESM1_ESM.docx (71 kb)
ESM 1 (DOCX 70.5 KB)


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Copyright information

© Society of General Internal Medicine 2018

Authors and Affiliations

  • Wenjia Chen
    • 1
  • Don D. Sin
    • 2
    • 3
  • J. Mark FitzGerald
    • 3
    • 4
    • 5
  • Mohsen Sadatsafavi
    • 1
    • 4
  • for the Canadian Respiratory Research Network
  1. 1.Collaboration for Outcomes Research and Evaluation, Faculty of Pharmaceutical SciencesUniversity of British ColumbiaVancouverCanada
  2. 2.Division of Respiratory Medicine, Department of Medicine, The UBC Centre for Heart Lung Innovation, St. Paul’s HospitalUniversity of British ColumbiaVancouverCanada
  3. 3.Institute for Heart and Lung Health, Division of Respiratory Medicine, Faculty of MedicineUniversity of British ColumbiaVancouverCanada
  4. 4.Centre for Clinical Epidemiology and EvaluationUniversity of British ColumbiaVancouverCanada
  5. 5.UBC Division of Respiratory Medicine, Department of Medicine, The Lung CentreGordon and Leslie Diamond Health Care CentreVancouverCanada

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