title: First results from an intensified monitoring system to estimate drug related hospital admissions.
abstract: OBJECTIVE
  An intensified monitoring system was set up to identify drug related hospital admissions and estimate population-based incidences for commonly prescribed medications.
  
  
  METHODS
  Pharmacovigilance-centres systematically screened nonelective admissions to emergency rooms or departments of internal medicine for drug related hospitalizations (DRH). Clinical pharmacologists used standardized causality assessment. Service areas of each acute care hospital were defined by 5 digit postal codes that covered 60% of all admissions. Drug dispensing information was available through claims processed by regional pharmacy computing centres. Quarterly incidences were estimated by dividing the number of events by the number of treated patients.
  
  
  RESULTS
  435 DRHs were reported during five quarters. The incidence of ADRs leading to admissions varied for specific drug groups from 1.5/10 000 treated patients to 24/10 000. Quarterly variation of incidences was moderate except for insulin and calcium antagonists. 95% confidence intervals overlap for all quarters within each group. Incidences are sensitive to changes in the definition of the source population.
  
  
  CONCLUSIONS
  Our pharmacovigilance monitoring system allows comparisons of population-based incidences of drug-related hospitalizations among drugs and over time. It provides important information for risk management and monitoring outcomes of pharmaceutical quality management programmes.
authors.affiliation: Department of Medical Informatics, Biometry and Epidemiology, Pharmacoepidemiology Research Group, Ludwig-Maximilians-University, Munich, Germany. schneeweiss@post.harvard.edu
authors.forename: S
authors.initials: S
authors.lastname: Schneeweiss
authors.forename: M
authors.initials: M
authors.lastname: Göttler
authors.forename: J
authors.initials: J
authors.lastname: Hasford
authors.forename: W
authors.initials: W
authors.lastname: Swoboda
authors.forename: M
authors.initials: M
authors.lastname: Hippius
authors.forename: A K
authors.initials: AK
authors.lastname: Hoffmann
authors.forename: A K
authors.initials: AK
authors.lastname: Riethling
authors.forename: J
authors.initials: J
authors.lastname: Krappweis
mesh_terms: D016907:Adverse Drug Reaction Reporting Systems; D018672:Community Health Planning; D016903:Drug Monitoring; D064420:Drug-Related Side Effects and Adverse Reactions; D006801:Humans; D015994:Incidence; D010343:Patient Admission / Q000706:statistics & numerical data*