Quality of Life Research

, Volume 24, Issue 10, pp 2507–2517 | Cite as

The added effect of comorbidity on health-related quality of life in patients with asthma

  • Wenjia Chen
  • Larry D. Lynd
  • J. Mark FitzGerald
  • Carlo A. Marra
  • Roxanne Rousseau
  • Mohsen Sadatsafavi



To examine the effect of comorbidities on health-related quality of life (HRQoL) and their interaction with asthma control.


In a random sample of adults with asthma, we measured generic (EQ5D) and disease-specific (AQ5D) utility scores. Asthma symptom control was determined using the 2014 Global Initiative for Asthma Management Strategy. Comorbidity scores were calculated using a validated questionnaire. We used two-part regression models to measure the adjusted difference in utility across levels of symptom control and comorbidity scores and to examine the relative role of symptom control and comorbidity in explaining the variation in HRQoL.


A total of 2,299 observations from 460 adult patients (mean age 52 years, 67 % women) were included. Compared to controlled asthma, uncontrolled asthma was associated with −0.018 reduction (95 % CI −0.028, −0.009) in EQ5D and −0.076 reduction (95 % CI −0.115, −0.052) in AQ5D utilities. An increase by one standard deviation in comorbidity score relative to the mean was associated with a change of −0.029 (95 % CI −0.043, −0.016) in EQ5D and −0.010 (95 % CI −0.020, −0.004) in AQLQ utilities. The impact of comorbidity was greater than asthma symptom control in explaining EQ5D variance (12 vs. 1 %) but smaller in explaining AQ5D variance (3 vs. 12 %).


Generic and disease-specific HRQoL instruments differentially capture the impact of symptom control and comorbidity in asthma. The selection of HRQoL instruments for asthma studies should depend on the prevalence of comorbidity in the target population and the impact of interventions on asthma control and comorbidity.


Asthma control Comorbidity Health-related quality of life Generic instrument Disease-specific instrument Utility 

Supplementary material

11136_2015_995_MOESM1_ESM.pdf (102 kb)
Supplementary material 1 (PDF 101 kb)


  1. 1.
    To, T., Stanojevic, S., Moores, G., Gershon, A. S., Bateman, E. D., Cruz, A. A., et al. (2012). Global asthma prevalence in adults: Findings from the cross-sectional world health survey. BMC Public Health, 12, 204.PubMedCentralCrossRefPubMedGoogle Scholar
  2. 2.
    Chen, H., Gould, M. K., Blanc, P. D., Miller, D. P., Kamath, T. V., Lee, J. H., et al. (2007). Asthma control, severity, and quality of life: Quantifying the effect of uncontrolled disease. Journal of Allergy and Clinical Immunology, 120(2), 396–402.CrossRefPubMedGoogle Scholar
  3. 3.
    Bateman, E. D., Hurd, S. S., Barnes, P. J., Bousquet, J., Drazen, J. M., FitzGerald, M., et al. (2008). Global strategy for asthma management and prevention: GINA executive summary. European Respiratory Journal, 31(1), 143–178.CrossRefPubMedGoogle Scholar
  4. 4.
    Reddel, H. K., Taylor, D. R., Bateman, E. D., Boulet, L.-P., Boushey, H. A., Busse, W. W., et al. (2009). An official American Thoracic Society/European Respiratory Society statement: Asthma control and exacerbations: Standardizing endpoints for clinical asthma trials and clinical practice. American Journal of Respiratory and Critical Care Medicine, 180(1), 59–99.CrossRefPubMedGoogle Scholar
  5. 5.
    Rabin, R., & De Charro, F. (2001). EQ-5D: A measure of health status from the EuroQol Group. Annals of Medicine, 33(5), 337–343.CrossRefPubMedGoogle Scholar
  6. 6.
    Juniper, E. F., Guyatt, G. H., Epstein, R. S., Ferrie, P. J., Jaeschke, R., & Hiller, T. K. (1992). Evaluation of impairment of health related quality of life in asthma: Development of a questionnaire for use in clinical trials. Thorax, 47(2), 76–83.PubMedCentralCrossRefPubMedGoogle Scholar
  7. 7.
    Yang, Y., Brazier, J. E., Tsuchiya, A., & Young, T. A. (2011). Estimating a preference-based index for a 5-dimensional health state classification for asthma derived from the asthma quality of life questionnaire. Medical Decision Making, 31(2), 281–291.CrossRefPubMedGoogle Scholar
  8. 8.
    Whitehead, S. J., & Ali, S. (2010). Health outcomes in economic evaluation: The QALY and utilities. British Medical Bulletin, 96(1), 5–21.CrossRefPubMedGoogle Scholar
  9. 9.
    McTaggart-Cowan, H. M., Marra, C. A., Yang, Y., Brazier, J. E., Kopec, J. A., FitzGerald, J. M., et al. (2008). The validity of generic and condition-specific preference-based instruments: The ability to discriminate asthma control status. Quality of Life Research, 17(3), 453–462.CrossRefPubMedGoogle Scholar
  10. 10.
    Braido, F., Baiardini, I., Balestracci, S., Fassio, O., Ravera, S., Bellotti, M., et al. (2008). The relationship between asthma control and quality-of-life impairment due to chronic cough: A real-life study. Annals of Allergy, Asthma & Immunology, 101(4), 370–374.CrossRefGoogle Scholar
  11. 11.
    Doz, M., Chouaid, C., Com-Ruelle, L., Calvo, E., Brosa, M., Robert, J., et al. (2013). The association between asthma control, health care costs, and quality of life in France and Spain. BMC Pulmonary Medicine, 13, 15.PubMedCentralCrossRefPubMedGoogle Scholar
  12. 12.
    Vietri, J., Burslem, K., & Su, J. (2014). Poor Asthma control among US workers: Health-related quality of life, work impairment, and health care use. Journal of Occupational and Environmental Medicine, 56(4), 425–430.CrossRefPubMedGoogle Scholar
  13. 13.
    Ledford, D. K., & Lockey, R. F. (2013). Asthma and comorbidities. Current opinion in Allergy and Clinical Immunology, 13(1), 78–86.CrossRefPubMedGoogle Scholar
  14. 14.
    Soriano, J. B., Visick, G. T., Muellerova, H., Payvandi, N., & Hansell, A. L. (2005). Patterns of comorbidities in newly diagnosed COPD and asthma in primary care. Chest, 128(4), 2099–2107.CrossRefPubMedGoogle Scholar
  15. 15.
    Van Manen, J. G., Bindels, P. J., IJzermans, C. J., Van der Zee, J. S., Bottema, B. J., & Schadé, E. (2001). Prevalence of comorbidity in patients with a chronic airway obstruction and controls over the age of 40. Journal of Clinical Epidemiology, 54(3), 287–293.CrossRefPubMedGoogle Scholar
  16. 16.
    Wijnhoven, H. A. H., Kriegsman, D. M. W., Hesselink, A. E., De Haan, M., & Schellevis, F. G. (2003). The influence of co-morbidity on health-related quality of life in asthma and COPD patients. Respiratory Medicine, 97(5), 468–475.CrossRefPubMedGoogle Scholar
  17. 17.
    Deshmukh, V. M., Toelle, B. G., Usherwood, T., O’Grady, B., & Jenkins, C. R. (2008). The association of comorbid anxiety and depression with asthma-related quality of life and symptom perception in adults. Respirology, 13(5), 695–702.CrossRefPubMedGoogle Scholar
  18. 18.
    Al-kalemji, A., Petersen, K. D., Sørensen, J., Sherson, D., Thilsing, T., Schlünssen, V., et al. (2013). Factors influencing quality of life in asthmatics–a case-control study. The Clinical Respiratory Journal, 7(3), 288–296.CrossRefPubMedGoogle Scholar
  19. 19.
    Pérez De Llano, L. A., González, F. C., Añón, O. C., Perea, M. P., Caruncho, M. V., Villar, A. B., et al. (2010). [Relationship between comorbidity and asthma control]. [Article in Spanish]. Archivos de Bronconeumología, 46(10), 508–513.Google Scholar
  20. 20.
    GINA Report. (2014). Global strategy for asthma management and prevention. http://www.ginasthma.org/documents/4. Accessed 4 July 2014.
  21. 21.
    Labre, M. P., Herman, E. J., Dumitru, G. G., Valenzuela, K. A., & Cechman, C. L. (2012). Public health interventions for asthma: An umbrella review, 1990–2010. American Journal of Preventive Medicine, 42(4), 403–410.CrossRefPubMedGoogle Scholar
  22. 22.
    McQuaid, E. L., Garro, A., Seifer, R., Hammond, S. K., & Borrelli, B. (2012). Integrating asthma education and smoking cessation for parents: Financial return on investment. Pediatric Pulmonology, 47(10), 950–955.PubMedCentralCrossRefPubMedGoogle Scholar
  23. 23.
    Stenius-Aarniala, B., Poussa, T., Kvarnström, J., Grönlund, E. L., Ylikahri, M., & Mustajoki, P. (2000). Immediate and long term effects of weight reduction in obese people with asthma: Randomised controlled study. BMJ, 320(7238), 827–832.PubMedCentralCrossRefPubMedGoogle Scholar
  24. 24.
    Aaron, S. D., Fergusson, D., Dent, R., Chen, Y., Vandemheen, K. L., & Dales, R. E. (2004). Effect of weight reduction on respiratory function and airway reactivity in obese women. Chest, 125(6), 2046–2052.CrossRefPubMedGoogle Scholar
  25. 25.
    Chen, W., Fitzgerald, J. M., Rousseau, R., Lynd, L. D., Tan, W. C., & Sadatsafavi, M. (2013). Complementary and alternative asthma treatments and their association with asthma control: A population-based study. BMJ Open, 3(9), e003360.PubMedCentralCrossRefPubMedGoogle Scholar
  26. 26.
    Open Data from the Census—BC Stats. (2014). http://www.bcstats.gov.bc.ca/StatisticsBySubject/Census/OpenData.aspx. Accessed 4 July 2014.
  27. 27.
    Rabin, R., & De Charro, F. (2001). EQ-5D: A measure of health status from the EuroQol Group. Annals of Medicine, 33(5), 337–343.CrossRefPubMedGoogle Scholar
  28. 28.
    Juniper, E. F., Guyatt, G. H., Cox, F. M., Ferrie, P. J., & King, D. R. (1999). Development and validation of the mini asthma quality of life questionnaire. European Respiratory Journal, 14(1), 32–38.CrossRefPubMedGoogle Scholar
  29. 29.
    Bansback, N., Tsuchiya, A., Brazier, J., & Anis, A. (2012). Canadian valuation of EQ-5D health states: Preliminary value Set and considerations for future valuation studies. PLoS One, 7(2), e31115.PubMedCentralCrossRefPubMedGoogle Scholar
  30. 30.
    Dolan, P., Gudex, C., Kind, P., & Williams, A. (1996). The time trade-off method: Results from a general population study. Health Economics, 5(2), 141–154.CrossRefPubMedGoogle Scholar
  31. 31.
    Young, T. A., Yang, Y., Brazier, J. E., & Tsuchiya, A. (2011). The use of rasch analysis in reducing a large condition-specific instrument for preference valuation: The case of moving from AQLQ to AQL-5D. Medical Decision Making, 31(1), 195–210.CrossRefPubMedGoogle Scholar
  32. 32.
    Sangha, O., Stucki, G., Liang, M. H., Fossel, A. H., & Katz, J. N. (2003). The self-administered comorbidity questionnaire: A new method to assess comorbidity for clinical and health services research. Arthritis and Rheumatism, 49(2), 156–163.CrossRefPubMedGoogle Scholar
  33. 33.
    Olomu, A. B., Corser, W. D., Stommel, M., Xie, Y., & Holmes-Rovner, M. (2012). Do self-report and medical record comorbidity data predict longitudinal functional capacity and quality of life health outcomes similarly? BMC Health Services Research, 12, 398.PubMedCentralCrossRefPubMedGoogle Scholar
  34. 34.
    Blais, L., Kettani, F.-Z., Beauchesne, M.-F., Lemière, C., Perreault, S., & Forget, A. (2011). New measure of adherence adjusted for prescription patterns: The case of adults with asthma treated with inhaled corticosteroid monotherapy. Annals of Pharmacotherapy, 45(3), 335–341.CrossRefPubMedGoogle Scholar
  35. 35.
    Buntin, M. B., & Zaslavsky, A. M. (2004). Too much ado about two-part models and transformation? Comparing methods of modeling medicare expenditures. Journal of Health Economics, 23(3), 525–542.CrossRefPubMedGoogle Scholar
  36. 36.
    Zeger, S., Liang, K., & Albert, P. (1989). Models for longitudinal data: A generalized estimating equation approach. Biometrics, 1989(1), 347.Google Scholar
  37. 37.
    Austin, P. C., & Urbach, D. R. (2013). Using G-computation to estimate the effect of regionalization of surgical services on the absolute reduction in the occurrence of adverse patient outcomes. Medical Care, 51(9), 797–805.CrossRefPubMedGoogle Scholar
  38. 38.
    Walters, S. J., & Brazier, J. E. (2005). Comparison of the minimally important difference for two health state utility measures: EQ-5D and SF-6D. Quality of Life Research, 14(6), 1523–1532.CrossRefPubMedGoogle Scholar
  39. 39.
    Xuan, J., Kirchdoerfer, L. J., Boyer, J. G., & Norwood, G. J. (1999). Effects of comorbidity on health-related quality-of-life scores: An analysis of clinical trial data. Clinical Therapeutics, 21(2), 383–403.CrossRefPubMedGoogle Scholar
  40. 40.
    Pickard, A. S., Wilke, C., Jung, E., Patel, S., Stavem, K., & Lee, T. A. (2008). Use of a preference-based measure of health (EQ-5D) in COPD and asthma. Respiratory Medicine, 102(4), 519–536.CrossRefPubMedGoogle Scholar
  41. 41.
    Brazier, J., Akehurst, R., Brennan, A., Dolan, P., Claxton, K., McCabe, C., et al. (2005). Should patients have a greater role in valuing health states? Applied Health Economics and Health Policy, 4(4), 201–208.CrossRefPubMedGoogle Scholar
  42. 42.
    Verbrugge, L. M., Lepkowski, J. M., & Imanaka, Y. (1989). Comorbidity and its impact on disability. The Milbank Quarterly, 67(3–4), 450–484.CrossRefPubMedGoogle Scholar
  43. 43.
    Penninx, B. W. J. H., Beekman, A. T. F., Ormel, J., Kriegsman, D. M. W., Boeke, A. J. P., Van Eijk, J. T. M., et al. (1996). Psychological status among elderly people with chronic diseases: Does type of disease play a part? Journal of Psychosomatic Research, 40(5), 521–534.CrossRefPubMedGoogle Scholar
  44. 44.
    Johnson, J. A., Luo, N., Shaw, J. W., Kind, P., & Coons, S. J. (2005). Valuations of EQ-5D health states: Are the United States and United Kingdom different? Medical Care, 43(3), 221–228.CrossRefPubMedGoogle Scholar
  45. 45.
    Fryback, D. G., Palta, M., Cherepanov, D., Bolt, D., & Kim, J.-S. (2010). Comparison of 5 health-related quality-of-life indexes using item response theory analysis. Medical Decision Making, 30(1), 5–15.PubMedCentralCrossRefPubMedGoogle Scholar
  46. 46.
    Frank, K. A. (2000). Impact of a confounding variable on a regression coefficient. Sociological Methods & Research, 29(2), 147–194.CrossRefGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Wenjia Chen
    • 1
  • Larry D. Lynd
    • 1
    • 4
  • J. Mark FitzGerald
    • 2
    • 3
    • 5
  • Carlo A. Marra
    • 1
    • 4
  • Roxanne Rousseau
    • 2
  • Mohsen Sadatsafavi
    • 2
    • 3
    • 5
  1. 1.Collaboration for Outcomes Research and Evaluation, Faculty of Pharmaceutical SciencesUniversity of British ColumbiaVancouverCanada
  2. 2.Division of Respiratory Medicine, Faculty of MedicineUniversity of British ColumbiaVancouverCanada
  3. 3.Institute for Heart and Lung HealthUniversity of British ColumbiaVancouverCanada
  4. 4.Centre for Health Evaluation and Outcome SciencesProvidence Health Care Research InstituteVancouverCanada
  5. 5.Centre for Clinical Epidemiology and EvaluationVancouver Coastal Health Research InstituteVancouverCanada

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