title: Effect of methylphenidate formulation on treatment patterns and use of emergency room services.
abstract: OBJECTIVE
  The treatment patterns of and use of emergency room services by patients with attention-deficit/hyperactivity disorder (ADHD) who initiated therapy with thrice-daily, immediate-release (IR) methylphenidate versus once-daily, extended-release (ER) oral system methylphenidate were studied.
  
  
  METHODS
  Using a large claims database, patients who were newly initiated on either ER methylphenidate or IR methylphenidate were retrospectively identified. Analysis of covariance was used to examine differences in treatment patterns between individuals who initiated therapy on ER methylphenidate and those who initiated therapy on IR methylphenidate. Multivariate regressions were used to examine the probability of visiting the emergency room and the number of visits to the emergency room.
  
  
  RESULTS
  Of the 5939 patients who met the inclusion criteria, 4785 were initiated on ER methylphenidate and 1154 were initiated on IR methylphenidate. Significantly fewer patients initiated on ER methylphenidate had a 15- or 30-day gap in therapy or switched to another ADHD medication (p < 0.0001 for all comparisons). In addition, patients initiated on the ER formulation had a significantly longer duration of therapy than did those who received IR methylphenidate (p < 0.0001). Patients who received initial treatment with ER methylphenidate were also significantly less likely to visit an emergency room (odds ratio, 0.79; p = 0.01) and had, on average, 0.21 fewer visit to the emergency room (p = 0.0101).
  
  
  CONCLUSIONS
  A retrospective analysis of a patient database demonstrated that initial treatment with ER methylphenidate for patients with ADHD was associated with longer treatment periods, fewer switches in therapy, increased patient adherence, and a lower usage rate of emergency room services compared with initial treatment with IR methylphenidate.
authors.affiliation: Medical Science Liaison, Ortho Urology, McNeil Consumer and Specialty Products, Fort Washington, PA, USA.
authors.forename: Jason E
authors.initials: JE
authors.lastname: Kemner
authors.forename: Maureen J
authors.initials: MJ
authors.lastname: Lage
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy*; D000697:Central Nervous System Stimulants / Q000008:administration & dosage* / Q000627:therapeutic use; D002648:Child; D019992:Databases as Topic; D003692:Delayed-Action Preparations; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008774:Methylphenidate / Q000008:administration & dosage* / Q000627:therapeutic use; D008875:Middle Aged; D010349:Patient Compliance
chemical_list: D000697:Central Nervous System Stimulants; D003692:Delayed-Action Preparations; D008774:Methylphenidate