Sociodemographic, lifestyle and clinical factors associated with good performance in paired associates learning (PAL) test in patients with schizophrenia

INTRODUCTION: Memory and learning deficits are central among cognitive deficits in schizophrenia. However, to a varying proportion ca. 20-25% of patients could not be considered deficit. OBJECTIVES: Description of sociodemographic, lifestyle and clinical factors related to good performance in PAL-test in schizophrenia patients. METHODS: Participants (N=4500) were members of the Finnish SUPER study on the genetic mechanisms of psychotic disorders (SUPER). The database of the Northern Finland Birth Cohort 1966 (NFBC 1966) was utilized as a reference data. Visual memory and new learning were assessed using Cambridge Neuropsychological Test Automated Battery (CANTAB) Paired Associates Learning (PAL) test. The 50(th) percentile scores (10 error score or less) for outcome measure total errors adjusted (TEA) of NFBC 1966 was used as a cut-off for good performance in PAL test. RESULTS: The sociodemographic and lifestyle factors related good performance for both sexes were: younger age (p<.001), higher basic education (p <.001), independent form of dwelling (p<.001), hazardous drinking (p <.001), cannabis use (p <.001) and being married (females p = 0.009, males p = 0.049). The clinical factors related to good performance for both sexes were not using antipsychotic medication regularly (p <.001), not using all psychotropic medication (females p=0.05, males p <.001), less hospitalization times due to psychosis (p <.001), younger age at first hospitalization due to psychosis (p <.001), lower number of hospitalization days (p <.001) and lower percentage of time in hospital after first psychosis episode (p <.001). CONCLUSIONS: Several factors related to good performance in the PAL–test in the crude analysis without any confounders.