Role of heat related gut-microbiota-brain-axis changes in psychosis (HEATMAP)

Higher ambient temperatures (HAT) and heatwaves have a detrimental impact on the morbidity and mortality associated with mental illnesses, particularly psychoses. Individuals with psychoses are more likely to be admitted to hospital and die during HAT and heatwaves. However, little is known about the mechanisms through which heat precipitates or exacerbates psychoses. High temperatures affect gut microbiota composition. Gut microbiota influence brain functioning through neural and biochemical mechanisms. Differences in gut microbiota may have a causal role in psychoses. Our goal is to understand how heat-related changes in gut microbiota precipitate or exacerbate psychoses. We will measure gut microbiota composition, microbial metabolites, inflammatory markers in stool and blood, and neurometabolite concentrations using magnetic resonance spectroscopy, in people with new-onset or relapse of psychoses under varying degrees of heat-stress. We will combine meteorological data, microclimate measurements, dietary habits, clinical profiles, gut microbiome, stool and blood metabolites, and neurometabolite data to build predictive models of heat-stress related gut-microbiota-brain-axis changes in psychoses. Simultaneously, we will explore the experiences and perceptions of individuals with psychoses on the impact of heat on their mental health, behavioural adaptations, and potential interventions. Our work will provide the basis for potential interventions and feasibility of their uptake.