title: Direct and indirect costs for adverse drug events identified in medical records across care levels, and their distribution among payers.
abstract: Adverse drug events (ADEs) cause considerable costs in hospitals. However, little is known about costs caused by ADEs outside hospitals, effects on productivity, and how the costs are distributed among payers.
  
  
  
  To describe the direct and indirect costs caused by ADEs, and their distribution among payers. Furthermore, to describe the distribution of patient out-of-pocket costs and lost productivity caused by ADEs according to socio-economic characteristics.
  
  
  
  In a random sample of 5025 adults in a Swedish county, prevalence-based costs for ADEs were calculated. Two different methods were used: 1) based on resource use judged to be caused by ADEs, and 2) as costs attributable to ADEs by comparing costs among individuals with ADEs to costs among matched controls. Payers of costs caused by ADEs were identified in medical records among those with ADEs (n = 596), and costs caused to individual patients were described by socio-economic characteristics.
  
  
  
  Costs for resource use caused by ADEs were €505 per patient with ADEs (95% confidence interval €345-665), of which 38% were indirect costs. Compared to matched controls, the costs attributable to ADEs were €1631, of which €410 were indirect costs. The local health authorities paid 58% of the costs caused by ADEs. Women had higher productivity loss than men (€426 vs. €109, p = 0.018). Out-of-pocket costs displaced a larger proportion of the disposable income among low-income earners than higher income earners (0.7% vs. 0.2%-0.3%).
  
  
  
  We used two methods to identify costs for ADEs, both identifying indirect costs as an important component of the overall costs for ADEs. Although the largest payers of costs caused by ADEs were the local health authorities responsible for direct costs, employers and patients costs for lost productivity contributed substantially. Our results indicate inequalities in costs caused by ADEs, by sex and income.
authors.affiliation: Nordic School of Public Health NHV, Box 121 33, SE-402 42 Gothenburg, Sweden. Electronic address: jennie_natanaelsson@hotmail.com.
authors.forename: Jennie
authors.initials: J
authors.lastname: Natanaelsson
authors.affiliation: Nordic School of Public Health NHV, Box 121 33, SE-402 42 Gothenburg, Sweden; EPID Research, Sweden. Electronic address: research@kmhakkarainen.com.
authors.forename: Katja M
authors.initials: KM
authors.lastname: Hakkarainen
authors.affiliation: Department of Medical and Health Sciences, Linköping University, SE-581 85 Linköping, Sweden; Futurum, Jönköping County Council, SE-551 85 Jönköping, Sweden. Electronic address: staffan.hagg@liu.se.
authors.forename: Staffan
authors.initials: S
authors.lastname: Hägg
authors.affiliation: Section of Epidemiology and Social Medicine, Department of Public Health and Community Medicine, Sahlgrenska Academy, University of Gothenburg, Box 453, SE-405 30 Gothenburg, Sweden. Electronic address: karolina.a.sundell@gu.se.
authors.forename: Karolina
authors.initials: K
authors.lastname: Andersson Sundell
authors.affiliation: Health Metrics, Sahlgrenska Academy, University of Gothenburg, Box 414, SE-405 30 Gothenburg, Sweden. Electronic address: max.petzold@amm.gu.se.
authors.forename: Max
authors.initials: M
authors.lastname: Petzold
authors.affiliation: Department of Learning, Informatics, Management and Ethics - LIME, Karolinska Institutet, Sweden. Electronic address: clas.rehnberg@ki.se.
authors.forename: Clas
authors.initials: C
authors.lastname: Rehnberg
authors.affiliation: Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden. Electronic address: Anna.Jonsson@rmv.se.
authors.forename: Anna K
authors.initials: AK
authors.lastname: Jönsson
authors.affiliation: Nordic School of Public Health NHV, Box 121 33, SE-402 42 Gothenburg, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, SE-171 77 Stockholm, Sweden. Electronic address: hanna.gyllensten@ki.se.
authors.forename: Hanna
authors.initials: H
authors.lastname: Gyllensten
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D064420:Drug-Related Side Effects and Adverse Reactions / Q000191:economics*; D005260:Female; D017048:Health Care Costs; D006801:Humans; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D013548:Sweden; D055815:Young Adult
keywords: Adverse drug event; Cost of illness; Drug therapy; Medical records; Pharmacoepidemiology; Propensity score matching