title: Cognitive functioning in substance abuse and dependence: a population-based study of young adults.
abstract: OBJECTIVE
  To investigate whether substance use disorders (SUDs) are associated with verbal intellectual ability, psychomotor processing speed, verbal and visual working memory, executive function and verbal learning in young adults, and to study the associations of SUD characteristics with cognitive performance.
  
  
  METHODS
  A population-based sample (n = 466) of young Finnish adults aged 21-35 years.
  
  
  METHODS
  Diagnostic assessment was based on all available information from a structured psychiatric interview (SCID-I) and in- and out-patient medical records. Established neuropsychological tests were used in the cognitive assessment. Confounding factors included in the analyses were comorbid psychiatric disorders and risk factors for SUDs, representing behavioural and affective factors, parental factors, early initiation of substance use and education-related factors.
  
  
  RESULTS
  Adjusted for age and gender, life-time DSM-IV SUD was associated with poorer verbal intellectual ability, as measured with the Wechsler Adult Intelligence Scale-Revised (WAIS-R) vocabulary subtest, and slower psychomotor processing, as measured with the WAIS-R digit symbol subtest. Poorer verbal intellectual ability was accounted for by parental and own low basic education, whereas the association with slower psychomotor processing remained after adjustment for SUD risk factors. Poorer verbal intellectual ability was related to substance abuse rather than dependence. Other SUD characteristics were not associated with cognition.
  
  
  CONCLUSIONS
  Poorer verbal intellectual ability and less efficient psychomotor processing are associated with life-time alcohol and other substance use disorders in young adulthood. Poorer verbal intellectual ability seems to be related to parental and own low basic education, whereas slower psychomotor processing is associated with SUD independently of risk factors.
authors.affiliation: Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Mannerheimintie 166, FIN-00271 Helsinki, Finland. antti.latvala@thl.fi
authors.forename: Antti
authors.initials: A
authors.lastname: Latvala
authors.forename: Anu E
authors.initials: AE
authors.lastname: Castaneda
authors.forename: Jonna
authors.initials: J
authors.lastname: Perälä
authors.forename: Samuli I
authors.initials: SI
authors.lastname: Saarni
authors.forename: Terhi
authors.initials: T
authors.lastname: Aalto-Setälä
authors.forename: Jouko
authors.initials: J
authors.lastname: Lönnqvist
authors.forename: Jaakko
authors.initials: J
authors.lastname: Kaprio
authors.forename: Jaana
authors.initials: J
authors.lastname: Suvisaari
authors.forename: Annamari
authors.initials: A
authors.lastname: Tuulio-Henriksson
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000139:chemically induced / Q000453:epidemiology / Q000523:psychology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D005387:Finland / Q000453:epidemiology; D006306:Health Surveys; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology*; D012307:Risk Factors; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000523:psychology*; D055815:Young Adult