The role of SOAT-1 polymorphisms in cognitive decline and delirium after bypass heart surgery

BACKGROUND: Cognitive decline (CD) and delirium (PD) are commonly observed complications after bypass heart surgery. In this study we aimed to investigate whether certain genetic factors (alleles of the SOAT-1 gene) play a role in their appearance. PATIENTS AND METHODS: We examined 137 patients receiving coronary bypass surgery with a neuropsychiatric test battery consisting of the Mini Mental State Examination (MMSE), the Brief Psychiatric Rating Scale (BPRS), the Wechsler's Memory Scale-Revised (WMS-R) on admission and one month after surgery, and the Delirium Rating Scale postoperatively, when indicated, and genotyped them in relation to the SOAT-1 genotypes (AA positive group with augmented protection of the nerve cells against stress and the AA negative group--AC and CC subgroups--with diminished protection against stress). RESULTS: We noted a significant decline in test results postoperatively and a high frequency of delirium (29.92% of the patients). None of these complications could be associated to the SOAT-1 genotypes. CONCLUSIONS: Our study confirmed the expected cognitive decline and highly frequent delirium after bypass heart surgery and excluded the possible role of SOAT-1 genotype polymorphisms in their genesis.