Excess medical costs in patients with asthma and the role of comorbidity.
Asthmatic patients frequently have comorbidities, but the role of comorbidities in the economic burden of asthma is unclear. We examined the excess direct medical costs, including asthma- and comorbidity-related costs, in patients with asthma.We created a propensity score-matched cohort of patients newly diagnosed with asthma and non-asthmatic comparison subjects, both aged 5-55 years, from health administrative data (1997-2012) in British Columbia, Canada. Health services use records were categorised into 16 major disease categories based on International Classification of Diseases codes. Excess costs (in 2013 Canadian dollars ($)) were estimated as the adjusted difference in direct medical costs between the two groups.Average overall excess costs were estimated at $1058/person-year (95% CI 1006-1110), of which $134 (95% CI 132-136) was attributable to asthma and $689 (95% CI 649-730) to major comorbidity classes. Psychiatric disorders were the largest component of excess comorbidity costs, followed by digestive disorders, diseases of the nervous system, and respiratory diseases other than asthma. Comorbidity-attributable excess costs greatly increased with age but did not increase over the time course of asthma.These findings suggest that both asthma and comorbidity-related outcomes should be considered in formulating evidence-based policies and guidelines for asthma management.
Collaboration for Outcomes Research and Evaluation, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada wenjia.chen@alumni.ubc.ca.|Institute for Heart and Lung Health, Division of Respiratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.
Wenjia
W
Chen
Collaboration for Outcomes Research and Evaluation, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada.|Centre for Health Evaluation and Outcome Sciences, Providence Health, St. Paul's Hospital, Vancouver, BC, Canada.
Larry D
LD
Lynd
Institute for Heart and Lung Health, Division of Respiratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.|Centre for Clinical Epidemiology and Evaluation, University of British Columbia, Vancouver, BC, Canada.
J Mark
JM
FitzGerald
New Zealand's National School of Pharmacy, University of Otago, Dunedin, New Zealand.
Carlo A
CA
Marra
BC Centre for Disease Control, Vancouver, BC, Canada.
Robert
R
Balshaw
The Hospital for Sick Children, Toronto, ON, Canada.
Teresa
T
To
Institute for Heart and Lung Health, Division of Respiratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.|Centre for Clinical Epidemiology and Evaluation, University of British Columbia, Vancouver, BC, Canada.
Hamid
H
Tavakoli
Collaboration for Outcomes Research and Evaluation, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada.|Institute for Heart and Lung Health, Division of Respiratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.|Centre for Clinical Epidemiology and Evaluation, University of British Columbia, Vancouver, BC, Canada.
Mohsen
M
Sadatsafavi
D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000150:complications / Q000191:economics*; D001955:British Columbia; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D005102:Health Expenditures / Q000706:statistics & numerical data* / Q000639:trends*; D006296:Health Services / Q000191:economics*; D006801:Humans; D016015:Logistic Models; D008297:Male; D001523:Mental Disorders / Q000191:economics*; D008875:Middle Aged; D057216:Propensity Score; D055815:Young Adult