Endothelial function, folate pharmacogenomics, and neurocognition in psychotic disorders

Cardiovascular disease (CVD) is a well-described complication of schizophrenia, however, mechanisms connecting CVD with other facets of psychotic disorders, such as neurocognition, are not understood. The current study examined folate metabolism as a potential mechanism of CVD and neurocognitive deficits by: 1) using endothelial dysfunction as a biomarker of CVD, and 2) comparing enzymes associated with neurocognition, CVD, and critical to folate metabolism, methylenetetrahydrofolate reductase (MTHFR) and catechol-o-methyl transferase (COMT). Endothelial function was assessed in 147 participants with schizophrenia, schizoaffective disorder, and psychotic disorder not otherwise specified grouped by MTHFR and COMT allele status. Regression models were used to compare neurocognitive performance based on the Brief Assessment of Cognition in Schizophrenia (BACS). Overall, endothelial function predicted BACS composite z-scores after controlling for age, race, level of education, serum folate levels, and MTHFR/COMT risk allele status. Participants with at least one or more MTHFR and/or COMT risk alleles had lower BACS Composite and BACS Symbol Coding adjusted mean z-scores than those with both MTHFR CC and COMT Met/Met genotypes. Thus, endothelial dysfunction may contribute to the neurocognitive deficits seen in psychotic disorders. CVD interventions may not only reduce CVD-related morbidity, but also lessen progressive neurocognitive deficits reported in psychotic disorders.