International Journal of Clinical Pharmacy

, Volume 34, Issue 4, pp 538–546 | Cite as

Modelling drug-related morbidity in Sweden using an expert panel of pharmacists’

  • Hanna GyllenstenEmail author
  • Katja M. Hakkarainen
  • Anna K. Jönsson
  • Karolina Andersson Sundell
  • Staffan Hägg
  • Clas Rehnberg
  • Anders Carlsten
Research Article


Background Drug-related morbidity (DRM) is common and to some extent preventable, and associated with considerable costs in patients attending hospital. In outpatients and in the general public corresponding data are limited, but pharmacists’ expert opinion has suggested high rates of DRM also in US ambulatory care. It is unknown if the results are applicable in Sweden today. Objective To estimate the proportions of patients with DRM and preventable DRM and the cost-of-illness (COI) of DRM in Sweden based on pharmacists’ expert opinion. Setting Swedish healthcare. Method The study applied a conceptual model of DRM based on a decision tree. An expert panel of pharmacists determined the probabilities of therapeutic outcomes of medication therapy. The COI analysis included direct costs from the healthcare perspective. Sensitivity analyses were performed for variations in probabilities and pathway costs. Main outcome measure DRM included new medical problems (adverse drug reactions, drug dependence and intoxications) and therapeutic failures (insufficient effects of medicines and morbidity due to untreated indication). Results The expert panel estimated that 61 ± 14 % (mean ± SD) of all patients attending healthcare suffered from DRM, of which 29 ± 8 % suffered from new medical problems, 18 ± 6 % from therapeutic failures, and 15 ± 7 % from a combination of both. The DRM was considered preventable in 45 ± 15 % of the patients with DRM. The estimated COI was EUR 997 per patient attending healthcare, corresponding to an annual cost of EUR 6,600 million to the Swedish healthcare system. The COI ranged from EUR 490 to EUR 1,314 when varying the participants’ probabilities of DRM and clinical outcomes from the first to the third quartile. Of the pathway costs, the COI was most sensitive to variation in the cost of prolonged hospital stay (COI range EUR 953–1,306). Conclusion According to pharmacists’ expert opinion, a large proportion of patients in Sweden experience DRM and preventable DRM, and the estimated COI of DRM is extensive. Since observational studies have not addressed the burden of DRM to the general public, this study adds the pharmacists’ perception on DRM. Other healthcare professionals’ perceptions on DRM need to be investigated in future studies.


Adverse effects Cost of illness Decision trees Delphi technique Drug-related morbidity Drug therapy Preventability Sweden 



We thank all the participants, in the piloting of the decision tree and in the final study. We also like to thank Lyle Bootman and colleagues in the College of Pharmacy, University of Arizona, for appreciated contributions in the adaptation of the conceptual model.


The research is part of the DRUMS project (Drug-related morbidity and mortality in Sweden: prevalence, preventability and costs), and is funded by an unrestricted grant from The National Corporation of Swedish Pharmacies (Apoteket AB). The sponsor had no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the manuscript; and in the decision to submit the manuscript for publication. The authors’ work was independent from the sponsor.

Conflicts of interest

The authors have no conflicts of interest to declare. The opinions or assertions contained herein are the private views of the authors, and are not to be construed as official or as reflecting the views of the Medical Products Agency.


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Hanna Gyllensten
    • 1
    Email author
  • Katja M. Hakkarainen
    • 1
  • Anna K. Jönsson
    • 2
    • 3
  • Karolina Andersson Sundell
    • 1
  • Staffan Hägg
    • 2
    • 3
  • Clas Rehnberg
    • 4
  • Anders Carlsten
    • 1
    • 5
  1. 1.Nordic School of Public Health NHVGöteborgSweden
  2. 2.Department of Drug Research/Clinical Pharmacology, Faculty of Health SciencesLinköping UniversityLinköpingSweden
  3. 3.Department of Clinical PharmacologyCounty Council of ÖstergötlandLinköpingSweden
  4. 4.Department of Learning, Informatics, Management and Ethics—LIMEKarolinska InstitutetStockholmSweden
  5. 5.Medical Products AgencyUppsalaSweden

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