doi: bioRxiv preprint (128504, 259589 and 265097), MC-ITN EU-FP7 (607616) and Finnish Cultural Foundation (Ingrid, Toini and Olavi Martelius Grant 2018) for WH, Sigrid Juselius Foundation for JL, and Jalmari and Rauha Ahokkas Foundation for VS. The funders had no further role in the study design; nor in the collection, analysis, and interpretation of data, in the writing of the report, nor in the decision to submit the paper for publication.

Purpose Many aspects related to migration might predispose immigrants to mental health problems. Yet immigrants have been shown to underuse mental health services. The aim of this study was to compare the intensity of psychiatric care, as an indicator of treatment adequacy, between natives and immigrants living in Finland. Methods We used nationwide register data that included all the immigrants living in Finland at the end of 2010 (n = 185,605) and their matched controls. Only those who had used mental health services were included in the analyses (n = 14,285). We used multinomial logistic regression to predict the categorized treatment intensity by immigrant status, region and country of origin, length of residence, and other background variables. Results Immigrants used mental health services less than Finnish controls and with lower intensity. The length of residence in Finland increased the probability of higher treatment intensity. Immigrants from Eastern Europe, sub-Saharan Africa, the Middle East, and Northern Africa were at the highest risk of receiving low-intensity treatment. Conclusions Some immigrant groups seem to persistently receive less psychiatric treatment than Finnish-born controls. Identification of these groups is important and future research is needed to determine the mechanisms behind these patterns.

Schizophrenia is a heterogeneous disorder characterized by a spectrum of symptoms and many different underlying causes. Thus, instead of using the broad diagnosis, intermediate phenotypes can be used to possibly decrease the underlying complexity of the disorder. Alongside the classical symptoms of delusions and hallucinations, cognitive deficits are a core feature of schizophrenia. To increase our understanding of the biological processes related to these cognitive deficits, we performed a genome-wide gene expression analysis. A battery of 14 neuropsychological tests was administered to 844 individuals from a Finnish familial schizophrenia cohort. We grouped the applied neuropsychological tests into five factors for further analysis. Cognitive endophenotypes, whole blood mRNA, genotype, and medication use data were studied from 47 individuals. Expression level of several RNA probes were significantly associated with cognitive performance. The factor representing Verbal Working Memory was associated with altered expression levels of 11 probes, of which one probe was also associated with a specific sub-measure of this factor (WMS-R Digit span backward). While, the factor Processing speed was related to one probe, which additionally associated among 55 probes with a specific sub-measure of this factor (WAIS-R Digit symbol). Two probes were associated with the measure recognition memory performance. Enrichment analysis of these differentially expressed probes highlighted immunological processes. Our findings are in line with genome-wide genetic discoveries made in schizophrenia, suggesting that immunological processes may be of biological interest for future drug design towards schizophrenia and the cognitive dysfunctions that underlie it.