title: Drug treatment patterns of attention-deficit/hyperactivity disorder in children and adolescents in Germany: results from a large population-based cohort study.
abstract: OBJECTIVE
  Despite a substantial increase in total methylphenidate (MPH) prescriptions in Germany over the last 20 years, and the introduction of modified release MPH (MR MPH) and atomoxetine (ATX), remarkably little is known about treatment patterns of attention- deficit/hyperactivity disorder (ADHD) in individual patients.
  
  
  METHODS
  Usage patterns of ADHD drugs in children and adolescents in Germany were analyzed using data from one large German health insurance including >7,200,000 members. Of those, 6210 ADHD patients newly diagnosed in 2005 were followed for a maximum of 4 years. Kaplan-Meier estimates were calculated for onset and discontinuation of ADHD drug treatment. Predictors of time until drug treatment initiation were assessed by Cox regression.
  
  
  RESULTS
  During follow-up, 52.0% of ADHD subjects (53.4% of boys, 47.5% of girls) received ADHD drug treatment. The majority of them (91.6%) were started on MPH, with immediate release MPH (IR MPH) being the initial treatment choice in 75.3%. In these subjects, change to drug treatment with MR MPH in the first year occurred in 48% by switch or addition. Significant predictors of drug treatment were behavioral and emotional disorders (HR=1.13; 95% CI 1.03-1.24) and a diagnosis of ADHD with conduct disorder (HR=1.21, 95% CI 1.12-1.32), whereas young age showed a protective effect. After 6, 12, and 24 months of treatment initiation, 22.4%, 43.4%, and 66.3% of treated girls, and 17.8%, 36.1%, and 54.1% of treated boys had discontinued ADHD treatment.
  
  
  CONCLUSIONS
  Drug treatment of ADHD was relatively common in Germany and more frequent in boys than in girls. IR MPH was the predominant treatment choice at treatment initiation. Approximately 20% of treated subjects discontinued drug treatment within the first 6 months, with girls stopping drug treatment earlier than boys. The reasons for early drug discontinuation need to be further explored.
authors.affiliation: BIPS-Institute for Epidemiology and Prevention Research, Bremen, Germany. garbe@bips.uni-bremen.de
authors.forename: Edeltraut
authors.initials: E
authors.lastname: Garbe
authors.forename: Rafael T
authors.initials: RT
authors.lastname: Mikolajczyk
authors.forename: Tobias
authors.initials: T
authors.lastname: Banaschewski
authors.forename: Ulrike
authors.initials: U
authors.lastname: Petermann
authors.forename: Franz
authors.initials: F
authors.lastname: Petermann
authors.forename: Angela A
authors.initials: AA
authors.lastname: Kraut
authors.forename: Ingo
authors.initials: I
authors.lastname: Langner
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D005500:Follow-Up Studies; D005858:Germany; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008774:Methylphenidate / Q000627:therapeutic use*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D016016:Proportional Hazards Models; D012737:Sex Factors; D013997:Time Factors
chemical_list: D000697:Central Nervous System Stimulants; D008774:Methylphenidate