ApoE基因多态性与老年患者术后认知功能障碍的关系

Relationship between ApoE gene polymorphism and postoperative cognitive dysfunction in elderly patients

目的评价载脂蛋白E(ApoE)基因多态性与老年患者术后认知功能障碍(POCD)的关系。方法选取择期膝关节置换术老年患者362例,年龄60~78岁,体重61.5~72.5 kg、ASA分级Ⅱ或Ⅲ级,简明心智评分检验量表评分>24分,均在脊椎-硬膜外联合麻醉下完成手术。于蛛网膜下腔穿刺成功后取脑脊液标本,采用ELISA法测定脑脊液β淀粉样蛋白42(Aβ-42)和总Tau蛋白(t-Tau)的浓度,计算Aβ-42/t-Tau比值。于术后7 d空腹采集静脉血样,采用PCR检测ApoE基因多态性,于术前1 d和术后7 d,进行神经心理学测试,根据心理学测试结果,分为非POCD组和POCD组。采用logistic回归分析筛选POCD的危险因素。结果与非POCD组比较,POCD组脑脊液t-Tau浓度升高,脑脊液Aβ-42浓度和Aβ-42/t-Tau比值降低,ε4基因型及等位基因频率升高,其他基因型及等位基因频率降低(P<0.05)。logistic回归分析显示:ApoEε4等位基因(OR值=2.847,95%可信区间1.957~11.512)为老年患者POCD的危险因素(P<0.05)。结论ApoE基因多态性(ApoEε4等位基因)可能与老年患者POCD的发生有关。

Objective To evaluate the relationship between apolipoprotein E(ApoE)gene polymorphism and postoperative cognitive dysfunction(POCD)in elderly patients.Methods A total of 362 orthopedic patients,aged 60-78 yr,weighing 61.5-72.5 kg,of American Society of Anesthesiologists physical statusⅡorⅢ,undergoing elective knee arthroplasty,with Mini-Mental State Examination score>24 points,completed surgery under combined spinal-epidural anesthesia,were selected.The cerebrospinal fluid(CSF)specimens were collected after successful subarachnoid puncture for determination of the concentrations of amyloidβ42(Aβ-42)and total Tau protein(t-Tau)by enzyme-linked immunosorbent assay.Aβ-42/t-Tau ratio was calculated.Venous blood samples were collected on an empty stomach at day 7 after operation,and polymerase chain reaction was used to detect the ApoE gene polymorphism.Psychological test was performed on 1 day before operation and 7 days after operation.The patients were divided into non-POCD group and POCD group according to the results of psychological test.The risk factors were identified by logistic regression analysis.Results Compared with non-POCD group,the concentrations of t-Tau in CSF were significantly increased,the concentrations of Aβ-42 in CSF and Aβ-42/t-Tau ratio were decreased,theε4 genotype and frequency of ApoE gene allele were increased,and the other genotypes and frequency of alleles were decreased in POCD group(P<0.05).The results of logistic regression analysis showed that ApoEε4 allele(OR=2.847,95%confidence interval 1.957-11.512)was a risk factor for POCD in elderly patients(P<0.05).Conclusion ApoE gene polymorphism(ApoEε4 allele)may be related to the development of POCD in elderly patients.