title: Paediatric post-marketing pharmacovigilance: comparison of the adverse event profile of vigabatrin prescribed to children and adults.
abstract: OBJECTIVE
  Post-marketing pharmacovigilance is a cornerstone of monitoring and evaluating the safety of medicines in children and adults. However the methods may require modification to detect paediatric signals. The aim of this study was to compare the adverse event (AE) profile of children and adults taking vigabatrin, using modified signal detection methods (SDMs).
  
  
  METHODS
  Data from the vigabatrin prescription-event monitoring study an observational cohort study (cohort 10,177 patients), stratified into one paediatric (0-17 years) and one adult (≥ 18 years) age group were examined using summary statistics for adverse drug reactions (ADRs), reasons for stopping and deaths. Incidence densities of AEs in children and adults in the first month of treatment were compared to months two to six to examine whether the AE rate was different in these two periods. AE rates in children were compared to those in adults (proportional reporting rates; PRRs and incidence rate ratios), to compare the AE profile between these age groups.
  
  
  RESULTS
  Abnormal behaviour (PRR 5.3) and hyperactivity (PRR 4.5) were more frequently reported in children; confusion (PRR 25.0) and psychosis (PRR 12.5) more frequently in adults. In children 11.8% of ADRs were reported to the regulatory authority compared to 27.3% in adults. A higher proportion of children stopped treatment due to lack of effectiveness (57.7% vs. 47.5%). No deaths were attributed to vigabatrin.
  
  
  CONCLUSIONS
  This study demonstrated that modified SDMs can be used to detect differences in the AE profiles between children and adults taking a medicinal product, and also to identify drug safety signals.
authors.affiliation: Drug Safety Reseach Unit, Department of Drug Safety, Bursledon Hall, Blundell Lane, Southampton, UK.
authors.forename: Beate
authors.initials: B
authors.lastname: Aurich-Barrera
authors.forename: Lynda
authors.initials: L
authors.lastname: Wilton
authors.forename: David
authors.initials: D
authors.lastname: Brown
authors.forename: Saad
authors.initials: S
authors.lastname: Shakir
mesh_terms: D000293:Adolescent; D000328:Adult; D016907:Adverse Drug Reaction Reporting Systems / Q000706:statistics & numerical data*; D000367:Age Factors; D000927:Anticonvulsants / Q000008:administration & dosage / Q000009:adverse effects*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D011358:Product Surveillance, Postmarketing / Q000379:methods; D020888:Vigabatrin / Q000008:administration & dosage / Q000009:adverse effects*
chemical_list: D000927:Anticonvulsants; D020888:Vigabatrin