title: Modelling drug-related morbidity in Sweden using an expert panel of pharmacists'.
abstract: 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.
  
  
  METHODS
  Swedish healthcare.
  
  
  METHODS
  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.
  
  
  METHODS
  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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: Nordic School of Public Health NHV, Box 12133, 402 42, Göteborg, Sweden. hanna.gyllensten@nhv.se
authors.forename: Hanna
authors.initials: H
authors.lastname: Gyllensten
authors.forename: Katja M
authors.initials: KM
authors.lastname: Hakkarainen
authors.forename: Anna K
authors.initials: AK
authors.lastname: Jönsson
authors.forename: Karolina
authors.initials: K
authors.lastname: Andersson Sundell
authors.forename: Staffan
authors.initials: S
authors.lastname: Hägg
authors.forename: Clas
authors.initials: C
authors.lastname: Rehnberg
authors.forename: Anders
authors.initials: A
authors.lastname: Carlsten
mesh_terms: D003663:Decision Trees; D064420:Drug-Related Side Effects and Adverse Reactions / Q000191:economics* / Q000453:epidemiology*; D017048:Health Care Costs / Q000706:statistics & numerical data*; D006801:Humans; D018803:Models, Economic; D009017:Morbidity; D010595:Pharmacists; D013548:Sweden / Q000453:epidemiology