腹膜透析患者容量超负荷与内皮功能障碍密切相关

Volume Overload is Related to Endothelial Dysfunction in Continuous Ambulatory Peritoneal Dialysis Patients

目的探讨腹膜透析患者容量超负荷是否通过对血管内皮的损害导致患者心血管疾病的高死亡率。方法采用横断面研究,选取81例持续非卧床腹膜透析患者为研究对象,容量指标用多频生物电阻抗分析仪测定,采用身高标化的细胞外液作为容量指标,用血流介导的扩张反应反映内皮功能,血流介导的扩张反应为反应性充血后内径变化与静息内径比值。结果有37例男性患者及44例女性患者入选本研究,平均年龄和透析龄分别是61±12岁和20±23个透析月。女性患者血流介导的扩张反应明显高于男性患者(9.17%±6.23%和6.31%±5.01%,P<0.05)。血流介导的扩张反应与体重(r=-0.308,P<0.01)、体质指数(r=-0.242,P<0.05)、收缩压(r=-0.228,P<0.05)、细胞外液(r=-0.404,P<0.001)和身高标化的细胞外液(r=-0.418,P<0.001)均存在负相关性。多元回归分析结果显示,身高标化的细胞外液(β=-0.343)、钙磷乘积(β=0.442)及透析龄(β=-0.237)是影响血流介导的扩张反应的独立决定因素(矫正R2=0.327)。结论身高标化的细胞外液较高的患者血管内皮功能较差,此结果有助于理解容量超负荷可增加腹膜透析患者心血管疾病的发生率和死亡率。

Aim To investigate whether volume overload poses its detrimental effect on cardiovascular mortality through endothelial dysfunction. Methods In this cross-sectional study, 81 stable patients on continuous ambulatory peritoneal dialysis （CAPD） in a single center were recruited. Volume status was evaluated with extracellular water normalized by individual height （NECW）, which was assessed by bioimpedanee analysis. Endothelial function was estimated by endothelial-dependent flow-mediated dilatation （FMD） of the braehial artery, which was expressed as the percentage change relative to the baseline diameter. Results There were 37 male and 44 female patients. Their mean age and dialysis duration were 61 ± 12 years and 20± 23 months, respectively. The FMD in female patients were significantly higher than that in male patients （9.17% ± 6.23% vs6.31%±5.01%, P〈0.05）. FMD was negatively correlated with weight （r= -0.308, P〈0.01）, bedy mass index （r= -0.242, P〈0.05）, systolic blood pressure （r= -0.228, P〈0.05）, ECW （r= -0.404, P〈0.001） and NECW （ r = - 0. 418, P 〈 0.001 ）. No correlation was found between FMD and other variabies. In multiple stepwise regression analysis, calcium x phosphate （ Ca x P） product （β = 0.422, P 〈 0.001 ）, NECW （β = - 0. 343, P 〈 0.01 ） and dialysis duration （ β = - 0. 237, P 〈 0.05 ） were independent determinants of FMI） （ adjusted R^2 = 0. 327 for this model ）. Conclusion Higher NECW was related to worse endothelial function. The results in this study may help us to understand the underlying mechanism of volume overload leading to increased cardiovascular morbidity and mortality in dialysis patients.