Association Of A CB1Cannabinoid Receptor Gene(CNR1) Polymorphism With Cognitive Dysfunction After Cardiac Surgery

Objectives:The physiological role of the ECS in cognition has been widely investigated.A silent polymorphism(1359G/A;Thr453Thr) was reported in the coding exon of CB1human cannabinoid receptor gene(CNR1).To study the association of a CNR1polymorphism with Postoperative Cognitive Dysfunction of cardiac surgery.Methods:Two hundred and thirty one patients (aged22-60years, with MoCA score≥26) undergoing cardiac valve replacement with CPB were studied. Blood samples were drawn to detect the CNR1gene expression before general anaesthesia. The patients were divided into two groups (one with POCD and one without) with the neuropsychological test applying MoCA (POCD was assessed with score<26) and DES-D both the day before surgery and the7th day following surgery. Applying the CAM-ICU to assess whether the patient is with delirium1-3days after surgery. The data associated with anesthesia and surgery was calculated. Observe the complications after surgery.Results:Two hundred and thirty one samples were analysised. The allelic frequency of CNR11359A was24.45%. As to the genotype, the frequency of the AA genotype in patients with POCD was less than those without POCD (P=0.209), but there was no statistical significance. However, the time spent for aorta blocking, CPB, postoperative ventilation and ICU monitoring by POCD group were longer than none-POCD group. The frequency of postoperative delirium was also higher in POCD group with a lower MoCA score got the day before discharge. According to the Logistic analysis, CPB time (OR=1.700,P=0.090) and the incidence of postoperative-delirium(OR=3.910,P=0.017) and the time of mechanical ventilation (OR=1.698,p=0.034) were the risks of POCD.Conclusions:No association was found between CNR11359G/A polymorphism and POCD. The time spent for CPB and mechanical ventilation and the incidence of delirium may be the risks of POCD.