title: Effect of methylphenidate on sleep parameters in children with ADHD.
abstract: OBJECTIVE
  The primary aim of this study was to investigate the acute impact of methylphenidate (MPH) on sleep parameters in attention-deficit/hyperactivity disorder (ADHD) children. The second aim was to investigate the different effects of intermediate- and longacting MPH on sleep parameters. The third aim was to test the different effects of dose and age on sleep parameters.
  
  
  METHODS
  Ninety-three ADHD children were enrolled and randomized to two different MPH preparations. Baseline and daily sleep diaries were evaluated for four weeks after taking medication. Weekday and weekend bedtimes, wake-up times, sleep latencies and total sleep times were compared by weeks.
  
  
  RESULTS
  After taking MPH, there was a significant delay in bedtimes and a significant reduction of total sleep time (TST) both on weekdays and at weekends. There was also a significant delay in wake-up time on weekdays. However, the difference was applied to younger age group children only. There was no difference in changes of TST between metadate-CD and OROS-MPH. There also was no difference in changes of TST with different doses of MPH.
  
  
  CONCLUSIONS
  MPH had negative impacts on sleep among young ADHD children, but different preparations and doses did not affect the result.
authors.affiliation: Department of Neuropsychiatry, Yeungnam University College of Medicine, Daegu, Republic of Korea.
authors.forename: Sang Heon
authors.initials: SH
authors.lastname: Lee
authors.forename: Wan Seok
authors.initials: WS
authors.lastname: Seo
authors.forename: Hyung Mo
authors.initials: HM
authors.lastname: Sung
authors.forename: Tae Young
authors.initials: TY
authors.lastname: Choi
authors.forename: So Yeun
authors.initials: SY
authors.lastname: Kim
authors.forename: So-Jeong
authors.initials: SJ
authors.lastname: Choi
authors.forename: Bon Hoon
authors.initials: BH
authors.lastname: Koo
authors.forename: Jong Hun
authors.initials: JH
authors.lastname: Lee