European Journal of Clinical Pharmacology

, Volume 68, Issue 9, pp 1309–1319 | Cite as

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

  • Katja M. Hakkarainen
  • Daniel Alström
  • Staffan Hägg
  • Anders Carlsten
  • Hanna Gyllensten
Pharmacoepidemiology and Prescription

Abstract

Purpose

In modelling studies using pharmacists’ opinions, drug-related morbidity (DRM) and preventable DRM have been more common than in observational studies, and the resulting costs are extensive. Modelling studies’ estimates may vary depending on informants’ profession. The purpose of this modelling study was to estimate the proportion of patients with DRM and preventable DRM and the cost of illness (COI) of DRM in Sweden based on physicians’ expert opinions.

Method

A conceptual model of DRM was modified from previous studies. Using a modified Delphi technique, a panel of physicians (n = 19) estimated the probabilities of DRM, preventable DRM, and clinical outcomes of DRM separately for outpatients and inpatients. DRM included new medical problems (adverse drug reactions, drug dependence, and intoxications by overdose) and therapeutic failure (insufficient effects of medicines, and morbidity due to untreated indication). A COI analysis included the direct costs of DRM.

Results

Physicians estimated that 51 ± 22% [mean ± standard deviation (SD)] of outpatients experience DRM and 12 ± 8% preventable DRM. Of inpatients, 54 ± 17% was estimated to experience DRM and 16 ± 7% preventable DRM. Of outpatients with DRM, 24 ± 11% was estimated to experience preventable DRM, whereas this proportion for inpatients was 31 ± 15%. The estimated COI was 376 euros per outpatient and 838 euros per inpatient.

Conclusions

Swedish physicians estimated that every other outpatient and inpatient experiences DRM, which is often preventable and costly. As physicians’ estimates on the proportion of patients with DRM were higher than in observational studies in restricted subpopulations, DRM may be more common in the general population than observational studies suggest.

Keywords

Drug-related morbidity Cost of illness Preventability Decision trees Pharmacoepidemiology 

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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Katja M. Hakkarainen
    • 1
  • Daniel Alström
    • 1
  • Staffan Hägg
    • 1
    • 2
    • 3
  • Anders Carlsten
    • 1
    • 4
  • Hanna Gyllensten
    • 1
  1. 1.Nordic School of Public Health NHVGothenburgSweden
  2. 2.Department of Drug Research/Clinical Pharmacology, Faculty of Health SciencesLinköping UniversityLinköpingSweden
  3. 3.Department of Clinical PharmacologyCounty Council of ÖstergötlandLinköpingSweden
  4. 4.Medical Products AgencyUppsalaSweden

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