Associations of social and genetic background variables to neuro-cognitive biomarkers of psychosis

Socioeconomic (SES) and ethno-racial factors may tilt psychosis diagnoses for persons from different backgrounds. Clinical diagnoses depend on patient and informant reports and are suspected of being susceptible to unintended bias. Diagnoses using laboratory tests are thought to be objective. Social disadvantages, however, alter brain functions related to psychosis. Race and class bias in laboratory medical diagnostics is an area of concern. To probe these issues for psychosis diagnoses, we describe relationships of SES, race/ethnicity, and ancestral genetic background to 11 integrated laboratory bio-factors that are associated with DSM categories and distinguish B-SNIP Biotypes. A series of analyses evaluated relationships of social factors and ancestry-related genetic background to those bio-factors: (i) canonical correlation revealed that SES and race (a social construct) are strongly associated (r 2 =.305) with cognitive performance and measures of brain physiology (prominently ERP magnitudes); genetic background neither significantly added to nor altered the structure of those associations; (ii) regression models illustrated that cognitive performance, intrinsic brain activity, and ERP magnitudes are substantially to modestly predicted by SES/race/genetic background, with SES/race accounting for the most variance on cognitive performance (approximately 25%); (iii) regardless of including SES/race in differential diagnosis models, group differences between psychosis Biotypes were largely (85%) preserved on bio-factor scores. For DSM diagnoses, less than 11% of psychosis group differences were preserved. These outcomes illustrate that social factors are associated with psychosis-related laboratory tests. Nevertheless, SES/race did not substantially modify differential diagnosis of psychosis Biotypes. Using laboratory tests for psychosis differential diagnosis may facilitate the usefulness of stratification approaches, aid investigations of psychosis neurobiology and environmental risk, and improve treatment selections and approaches for all persons suffering with idiopathic psychosis.