title: Adults with ADHD-without insomnia history have subclinical sleep disturbance but not circadian delay: an ADHD phenotype?
abstract: OBJECTIVE
  To explore the potential ADHD phenotype of ADHD-without reported insomnia in comparison with controls and their tolerance of stimulants in a cohort rigorously screened for comorbidities.
  
  
  METHODS
  Adults meeting Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR) criteria for ADHD-without insomnia and matched controls were administered a sleep/medication-timing questionnaire and the Pittsburgh Sleep Quality Index.
  
  
  RESULTS
  Among 105 participants, ADHD participants scored in the mild insomnia range and showed reduced sleep quality compared with controls, F(3, 101) = 34.9, p < .05, but no delay in bedtime/mid-sleep-time circadian measures. Sleep quality was similar between stimulant, nonstimulant, and unmedicated groups, χ(2) 2 = 0.445, p = .80. However, later timing of stimulant dosing was correlated with later sleep times, p < .01.
  
  
  CONCLUSIONS
  We isolated a potential phenotype of ADHD-without circadian delay in adults who demonstrated insomnia/sleep quality disturbance by sleep instrument, but lacked sleep-timing delay. Nevertheless, sleep delays were associated temporally with late-dosed stimulants in this group.
authors.affiliation: 1University of Alabama, Birmingham, USA.
authors.forename: Rachel E
authors.initials: RE
authors.lastname: Fargason
authors.forename: Abigail Fernandez
authors.initials: AF
authors.lastname: Hollar
authors.forename: Samantha
authors.initials: S
authors.lastname: White
authors.forename: Karen L
authors.initials: KL
authors.lastname: Gamble
mesh_terms: D000328:Adult; D000368:Aged; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications* / Q000188:drug therapy; D003913:Dextroamphetamine / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D020178:Sleep Disorders, Circadian Rhythm / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy; D007319:Sleep Initiation and Maintenance Disorders / Q000150:complications* / Q000188:drug therapy; D055815:Young Adult
chemical_list: D003913:Dextroamphetamine