Clinical and Biomarker-Based Trajectories of Psychosis-Risk Populations in Kenya

PROJECT SUMMARY Worldwide, up to 3% of people will experience psychosis, a heterogeneous neurodevelopmental and neurodegenerative brain disorder typically characterized by delusions, hallucinations, and functional decline. Currently, clinicians can identify adolescents and young adults who are at clinical high risk (CHR) for developing psychosis. However, as the mechanisms leading to development of psychosis are not fully known, we have limited ability to predict who will develop psychosis. Safe intervention in this population requires high confidence in predictive biomarkers that can stratify individuals into likely clinical trajectories, and match them with effective treatments. Africa has a very limited early psychosis research effort, resulting in a substantial gap in our knowledge about the ethnic heterogeneity of the high-risk state. Recently, a multi-site international effort, the Psychosis-Risk Outcomes Network (ProNET), was funded by the NIH to analyze variation in a diverse set of biomarkers to predict individual CHR clinical trajectories. However, while countries in North America, Europe and Asia are included in this landmark effort, it includes no African country. This is relevant, as risk genes for psychosis as well as the clinical and cultural presentation of psychosis often differ across ethnic groups. This proposal aims to build research capacity in Kenya, using state-of-the-art multimodal methods in Kenya identical to that applied in the ProNET study, in order to map clinical outcomes in CHR populations (Aim 1). This involves building ERP/EEG infrastructure in Nairobi, by acquiring research grade acquisition equipment and software; MRI upgrades, including advanced diffusion and fMRI BOLD imaging capability; and elaborate research training. In Aim 2, we will collect multi-modal biomarkers over 24 months (eight timepoints) from 100 CHR participants (aged 15-22) including brain MRI, ERP/EEG, psychopathology, cognition, genetics, and cortisol. Healthy volunteers (N=50) will complete baseline assessment to quantify typical variation. Aim 3 will test the hypothesis that psychosis outcomes in Kenyan CHR populations will differ from the international ProNET CHR cohort, including a lower rate of psychosis conversion and improved functioning. MRI and ERP analyses are expected to find orbitofrontal cortical thinning and reduced P300 (auditory P3b) amplitude with psychosis progression. Together, this work would address key existing knowledge gaps in global CHR research and provide insights into ethnic heterogeneity of outcomes among CHR patients. By building capacity in CHR clinical and biomarker- based research in Kenya, we will facilitate sub-Saharan Africa joining future international research efforts.