title: Impaired executive performance in healthy siblings of schizophrenia patients in a population-based study.
abstract: There is increasing evidence that healthy siblings of schizophrenia patients have similar, although milder, neuropsychological deficits than their affected family members. However, the interpretation of these findings has been complicated by methodological differences, for example the selection of relatives studied and the sensitivity of tests used. We studied neuropsychological functioning in schizophrenia families in representative, population-based samples of schizophrenia patients (n=81) and healthy siblings (n=78) from 58 families, and control subjects (n=70). We found that the healthy sibling group was impaired in tests measuring performance speed and executive functions. The patients were significantly impaired in all neuropsychological variables studied when compared with the control subjects, and also when compared with the healthy siblings. The effects of age, sex and education were controlled for. In conclusion, in a study of representative, population-based sample the healthy siblings of schizophrenia patients demonstrated deficits in processing speed and executive functions.
authors.affiliation: Department of Mental Health and Alcohol Research, National Public Health Institute, 00300 Helsinki Finland. annamaria.kuha@ktl.fi
authors.forename: Annamaria
authors.initials: A
authors.lastname: Kuha
authors.forename: Annamari
authors.initials: A
authors.lastname: Tuulio-Henriksson
authors.forename: Mervi
authors.initials: M
authors.lastname: Eerola
authors.forename: Jonna
authors.initials: J
authors.lastname: Perälä
authors.forename: Jaana
authors.initials: J
authors.lastname: Suvisaari
authors.forename: Timo
authors.initials: T
authors.lastname: Partonen
authors.forename: Jouko
authors.initials: J
authors.lastname: Lönnqvist
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011159:Population Surveillance; D012559:Schizophrenia / Q000175:diagnosis / Q000453:epidemiology* / Q000235:genetics; D012720:Severity of Illness Index; D035781:Siblings