title: Prevalence and incidence of adult attention deficit/hyperactivity disorder in a large managed care population.
abstract: OBJECTIVE
  To estimate longitudinal trends in prevalence and incidence rates of adult ADHD 2006-2009.
  
  
  METHODS
  Kaiser Permanente Southern California (KPSC) electronic medical records were analyzed to assess prevalence and incidence rates for adult ADHD. Trends over time were estimated and compared using three case definitions (ADHD diagnosis only [DX], ADHD DX and ≥2 FDA-approved ADHD prescriptions [DX + RX], and ADHD DX and ≥1 behavioral therapy visit [DX + BT]).
  
  
  METHODS
  Prevalence and incidence rates of adult ADHD.
  
  
  RESULTS
  Prevalence ranged from 151 (DX + RX) to 312 (DX) cases per 100,000 members in 2006, increasing to 239 (DX + RX) and 415 (DX) cases in 2009. Prevalence based on DX + BT declined from 185 in 2006 to 94 cases per 100,000 in 2009. In 2006, incidence ranged from 15 (DX + BT) to 68 (DX) cases per 100,000 person-years. Incidence rates remained stable throughout the study period. Stratified analyses based on DX + RX revealed only slight variations by gender, but sharp differences by age, with younger adults demonstrating a higher prevalence overall as well as dramatic increases over the study period. Prevalence was highest among Caucasians, increasing substantially across all race groups over time.
  
  
  CONCLUSIONS
  A limitation of this study is that incidence rates may not be representative of new cases if diagnoses existed prior to enrollment in KPSC. Similarly, prevalence rates may be affected if patients sought care outside of the health plan.
  
  
  CONCLUSIONS
  Adult ADHD prevalence in this managed care organization appears low, but showed increasing prevalence and incidence rates over time.
authors.affiliation: University of Southern California , Los Angeles, CA , USA.
authors.forename: Tara K
authors.initials: TK
authors.lastname: Knight
authors.forename: Aniket
authors.initials: A
authors.lastname: Kawatkar
authors.forename: Paul
authors.initials: P
authors.lastname: Hodgkins
authors.forename: Robert
authors.initials: R
authors.lastname: Moss
authors.forename: Li-Hao
authors.initials: LH
authors.lastname: Chu
authors.forename: Vanja
authors.initials: V
authors.lastname: Sikirica
authors.forename: M Haim
authors.initials: MH
authors.lastname: Erder
authors.forename: Michael B
authors.initials: MB
authors.lastname: Nichol
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000453:epidemiology*; D002140:California / Q000453:epidemiology; D015331:Cohort Studies; D057286:Electronic Health Records; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008329:Managed Care Programs; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D055815:Young Adult
keywords: Adult ADHD; Epidemiology; Incidence; Managed care; Prevalence