title: Predictors and consequences of adherence to the treatment of pediatric patients with attention-deficit/hyperactivity disorder in Central Europe and East Asia.
abstract: OBJECTIVE
  To assess baseline predictors and consequences of medication non-adherence in the treatment of pediatric patients with attention-deficit/hyperactivity disorder (ADHD) from Central Europe and East Asia.
  
  
  METHODS
  Data for this post-hoc analysis were taken from a 1-year prospective, observational study that included a total of 1,068 newly-diagnosed pediatric patients with ADHD symptoms from Central Europe and East Asia. Medication adherence during the week prior to each visit was assessed by treating physicians using a 5-point Likert scale, and then dichotomized into either adherent or non-adherent. Clinical severity was measured by the Clinical Global Impressions-ADHD-Severity (CGI-ADHD) scale and the Child Symptom Inventory-4 (CSI-4) Checklist. Health-Related Quality of Life (HRQoL) was measured using the Child Health and Illness Profile-Child Edition (CHIP-CE). Regression analyses were used to assess baseline predictors of overall adherence during follow-up, and the impact of time-varying adherence on subsequent outcomes: response (defined as a decrease of at least 1 point in CGI), changes in CGI-ADHD, CSI-4, and the five dimensions of CHIP-CE.
  
  
  RESULTS
  Of the 860 patients analyzed, 64.5% (71.6% in Central Europe and 55.5% in East Asia) were rated as adherent and 35.5% as non-adherent during follow-up. Being from East Asia was found to be a strong predictor of non-adherence. In East Asia, a family history of ADHD and parental emotional distress were associated with non-adherence, while having no other children living at home was associated with non-adherence in Central Europe as well as in the overall sample. Non-adherence was associated with poorer response and less improvement on CGI-ADHD and CSI-4, but not on CHIP-CE.
  
  
  CONCLUSIONS
  Non-adherence to medication is common in the treatment of ADHD, particularly in East Asia. Non-adherence was associated with poorer response and less improvement in clinical severity. A limitation of this study is that medication adherence was assessed by the treating clinician using a single item question.
authors.affiliation: Eli Lilly and Company, Windlesham, Surrey, UK.
authors.forename: Jihyung
authors.initials: J
authors.lastname: Hong
authors.forename: Diego
authors.initials: D
authors.lastname: Novick
authors.forename: Tamás
authors.initials: T
authors.lastname: Treuer
authors.forename: William
authors.initials: W
authors.lastname: Montgomery
authors.forename: Virginia S
authors.initials: VS
authors.lastname: Haynes
authors.forename: Shenghu
authors.initials: S
authors.lastname: Wu
authors.forename: Josep Maria
authors.initials: JM
authors.lastname: Haro
keywords: ADHD; Asia; Central Europe; effectiveness; non-adherence; response