S125. THE ROLE OF DUP, DUI AND POLYGENIC SCORE FOR SCHIZOPHRENIA ON COGNITION IN ATHENS FEP STUDY SAMPLE

Abstract

BackgroundIt remains unclear which biological mechanisms affect neurocognition in first episode psychosis (FEP) patients. There is minimal evidence from current literature suggesting an association between duration of untreated psychosis (DUP) or duration of untreated illness (DUI) and cognitive decline in FEP patients. It is still controversial whether genetic factors, such as polygenic risk score for schizophrenia, determine observed cognitive deficits. The study of interplay between DUP, DUI and genetic risk factors might be important to understand underlying pathways.MethodsNinety FEP patients where recruited during Athens First-Episode Psychosis Research study between 2015–2018. All participants provided inform consent. DUP for each patient was defined by NOS-DUP (Nottingham onset schedule: modified DUP version) assessment tool and DUI was determined using the symptom onset in schizophrenia (SOS) inventory. DNA was collected in order to create polygenic risk score (PGC) for schizophrenia for each individual using SNPs selected according to the significance of their association with the phenotype at nominal p-value thresholds of 0,05. WAIS-IV total score and subscales, i.e. Verbal Comprehension (VC), Perceptual Reasoning (PR), Working Memory (WM), Processing Speed (PS) and moreover index differences between these 4 subscales were applied as a measure of cognitive deficit.ResultsGeneralized linear model analysis, after adjustment for years of education and gender, found no significant main effect of DUP, DUI or PGC on any cognitive subscale. Furthermore, conducting an exploratory analysis for possible interactions between DUP/DUI and PGC (n=90), we found statistically significant findings of DUP x PGC (F=8,175, p=,005) and DUI x PGC (F=5,592, p=,021) for the cognitive variable of VC/WM difference. The interplay between DUP and PCG and DUI and PGC was associated with observed differences between VM and WM in our FEP sample.DiscussionOur preliminary results are consistent with recent literature suggesting that neurocognition is not determined by DUP, DUI or PGC for schizophrenia. Novel approach based on WAIS-IV indexes of interest allows to explore subtle differences between cognitive subdomains. Elucidating underlying interplay between genetic and disease-related mechanisms could be important to understand the core feature of cognitive deficit in FEP patients.