title: Is a schizo-obsessive subtype associated with cognitive impairment? Results from a large cross-sectional study in patients with psychosis and their unaffected relatives.
abstract: The current study investigated whether candidate cognitive endophenotypes may be used to validate a schizo-obsessive subtype. Using within-subject random effect regression analyses and cross-trait cross-relative analyses, we evaluated the association between obsessive-compulsive symptoms (OCSs) and cognitive performance in 984 patients with nonaffective psychosis (22.5% with OCSs), 973 unaffected siblings (7.7% with OCSs), 851 parents (4.2% with OCSs), and 573 controls (4.5% with OCSs). No significant within-subject associations between OCSs and cognitive functioning were found for patients and siblings. Severity of OCSs was associated with worse set-shifting ability in parents and worse processing speed in controls, but effect sizes were small (0.10 and 0.05 respectively). Cross-trait cross-relative analyses yielded no significant results. Contrary to our expectations, neither within-subject analyses nor cross-relative analyses yielded a clear association between OCSs and cognitive performance. Results do not support a schizo-obsessive subtype associated with cognitive impairment.
authors.affiliation: Academic Medical Centre University of Amsterdam, Department of Psychiatry, Amsterdam, the Netherlands.
authors.forename: Julia H
authors.initials: JH
authors.lastname: Meijer
authors.forename: Marije
authors.initials: M
authors.lastname: Swets
authors.forename: Soleil
authors.initials: S
authors.lastname: Keeman
authors.forename: Dorien H
authors.initials: DH
authors.lastname: Nieman
authors.forename: Carin J
authors.initials: CJ
authors.lastname: Meijer
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000453:epidemiology / Q000503:physiopathology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D009771:Obsessive-Compulsive Disorder / Q000145:classification / Q000453:epidemiology / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000145:classification / Q000453:epidemiology / Q000503:physiopathology*; D012720:Severity of Illness Index; D014888:Wechsler Scales