腹膜透析患者腹主动脉钙化与外周血淋巴细胞亚群的相关研究

目的探讨腹膜透析(peritoneal dialysis,PD)患者腹主动脉钙化(abdominal aortic calcification,AAC)与外周血淋巴细胞亚群之间的关系。方法收集86例PD患者临床资料,腹部侧位平片判断患者发生AAC的程度,并计算腹主动脉钙化积分(AAC score,AACs),依据患者的AACs分为3组:无和轻度钙化组(0≤AACs≤4分)41例、中度钙化组(5≤AACs≤15分)28例及重度钙化组(16≤AACs≤24)17例。利用流式细胞技术分别检测各组患者外周血中淋巴细胞亚群,其中包括CD3⁺、CD3⁺CD4⁺、CD3⁺CD8⁺、CD4⁺/CD8⁺、Treg、CD19⁺、CD16⁺CD56⁺等淋巴细胞的百分率及CD8⁺DR⁺淋巴细胞计数,计算CD4⁺/CD8⁺比值。采用Spearman相关性分析方法分析AAC与外周血淋巴细胞亚群及临床指标的相关性,用Logistic回归分析PD患者发生AAC的危险因素。结果3组患者年龄、原发病为糖尿病肾病、慢性肾小球肾炎以及白蛋白、血磷、碱性磷酸酶水平比较,差异有统计学意义(P<0.05)。Spearman相关性分析结果显示:AAC程度与患者的年龄、透析龄、甲状旁腺素、血磷、碱性磷酸酶、超敏C反应蛋白、CD4⁺/CD8⁺、CD16⁺CD56⁺、CD8⁺DR⁺呈正相关(r=0.352、0.284、0.226、0.299、0.265、0.285、0.236、0.228、0.292,P<0.05),与白蛋白、Treg呈负相关(r=-0.222、-0.354,P<0.05)。Logistic回归模型结果显示:年龄(OR=1.060,95%CI 1.008~1.116,P<0.05),CD4⁺/CD8⁺(OR=25.441,95%CI 1.561~414.659,P<0.05),Treg(OR=0.427,95%CI 0.255~0.715,P<0.05)是PD患者发生腹主动脉中重度钙化的独立预测因素。结论PD患者的AAC程度与外周血中淋巴细胞亚群改变具有相关性。Treg细胞百分率减少、CD4⁺/CD8⁺比值增加可能会加速AAC。PD患者外周血淋巴细胞亚群的改变可能会为AAC的防治提供新方向。

Correlation between abdominal aortic calcification and peripheral blood lymphocyte subsets in patients with peritoneal dialysis

Objective To explore the relationship between abdominal aortic calcification(AAC)and peripheral blood lymphocyte subsets in patients on peritoneal dialysis(PD).Methods The clinical data of 86 patients on PD were collected.Abdominal lateral plain film was taken for determining the occurrence of AAC and abdominal aortic calcification(AAC)score was calculated.Based upon the AAC scores,they were divided into three groups of non/mild calcification(0≤AACs≤4,n=41),moderate calcification(5≤AACs≤15,n=28)and severe calcification(16≤AACs≤24,n=17).Flow cytometry was utilized for detecting lymphocyte subsets in peripheral blood.The percentage of CD3⁺,CD3⁺CD4⁺,CD3⁺CD8⁺,CD4⁺/CD8⁺,Treg,CD19⁺,CD16⁺CD56⁺and CD8⁺DR⁺lymphocyte count and ratio of CD4⁺/CD8⁺were calculated.Spearman’s correlation analysis was performed for analyzing the correlation between AAC and peripheral blood lymphocyte subsets and clinical parameters.Logistic regression was employed for analyzing the risk factors of AAC in PD patients.Results Among three groups,statistically significant differences existed in age,diabetic nephropathy,chronic glomerulonephritis,albumin,blood phosphorus and alkaline phosphatase levels(P<0.05).Spearman’s correlation analysis indicated that degree of AAC was positively correlated with patient age,dialysis age,parathyroid hormone,blood phosphorus,alkaline phosphatase,high-sensitivity C-reactive protein,CD4⁺/CD8⁺,CD16⁺CD56⁺and CD8⁺DR⁺(r=0.352,0.284,0.226,0.299,0.265,0.285,0.236,0.228,0.292,P<0.05)and negatively correlated with albumin and Treg(r=-0.222,-0.354,P<0.05).Logistic regression model results implied that age(OR=1.060,95%CI 1.008~1.116,P<0.05),CD4⁺/CD8⁺(OR=25.441,95%CI 1.561~414.659,P<0.05)and Treg(OR=0.427,95%CI 0.255~0.715,P<0.05)were independent risk factors for moderate-to-severe AAC in PD patients.Conclusion The degree of AAC in PD patients has a certain correlation with the changes of lymphocyte subsets in peripheral blood.Lower percentage of Treg cells and higher ratio of CD4⁺/CD8⁺accelerate the progression of AAC.The change of peripheral blood lymphocyte subsets of PD patients may provide a new direction for the prevention and treatment of AAC.