目的 比较不同定义下透析中低血压(intradialytic hypotension,IDH)与维持性血液透析(maintenance hemodialysis,MHD)患者全因死亡的关系。 方法 回顾分析407名MHD患者数据，基于9 种不同定义选择K-M曲线差异最大时的IDH发生率作为截断值以区分频发IDH组与非频发IDH组，利用COX回归模型对比频发IDH与全因死亡的关联，同时通过C指数(C-index)、赤池信息准则(Akaike information criterion,AIC)、净重新分类指数(net reclassification index,NRI)和综合判别改善指数(integrated discrimination improvement,IDI)评价模型拟合效果及性能，最后利用限制性立方样条回归探讨IDH发生率与全因死亡的剂量-反应关系。 结果 近56个月的观察期内共收集了198 883次透析数据，最终35名(8.6%)患者死亡，平均死亡率为2.6人/100人年。各定义下从未发生过IDH的人数比例从0到46.4%不等，IDH平均发生率从0.7%到46.0%不等。矫正混杂变量后，基于英国肾脏协会指南定
义的频发IDH与全因死亡相关(HR=6.762,95%CI：3.272～13.977,P＜0.001)，模型C-ndex=0.749，AIC=380.957，NRI=0.381，IDI=0.093；IDH 发 生 率 与 全 因 死 亡 风 险 存 在 非 线 性 关 系 (Wald χ2=3.875,P=0.049)。 结论 IDH发生较普遍，在各定义间差异较大，重新界定后的IDH频发率在各定义间的差异有所减小。英国肾脏病协会指南定义下患者全因死亡风险随IDH发生频率增加而上升，频发IDH与全因死亡显著相关，且模型拟合效果及性能最优，能较好的评估死亡风险，在临床中更具有预测和指导意义。
Objective To compare the association between intradialytic hypotension (IDH) using different definitions and all- cause mortality in maintenance hemodialysis (MHD) patients. Methods Data from 407 patients were retrospectively analyzed. The K-M curves based on the 9 different definitions were established, and the cutoff value for the incidence of IDH with maximum difference in the K-M curve was used to distinguish frequent IDH from non-frequent IDH. Cox proportional hazard regression model was conducted to compare the correlation between frequent IDH and all-cause mortality. C-index, Akaike Information Criterion(AIC), Net Reclassification Index (NRI) and Integrated Discrimination Improvement (IDI) were used to evaluate efficiency and quality of the model. Finally, the dose-response effect between the frequency of IDH and allcause mortality was explored by strict cubic spline regression. Results A total of 198,883 dialysis data were collected during the 56-month follow-up period, and 35 patients (8.6%) died with an average death rate of 2.6 per 100 person-years. The proportion of never having IDH using an IDH definition ranged from 0% to 46.4%, and the average incidence of IDH ranged from 0.7% to 46.0%. After adjusting for confounding variables, frequent IDH that defined by the British Kidney Association (UKKA) guidelines was significantly associated with all-cause mortality (HR=6.762, 95% CI:3.272～13.977, P＜0.001). The C-index, AIC, NRI and IDI of the model were 0.749, 380.957, 0.381 and 0.093 respectively; there was a significant non-linear relationship between the frequency of IDH and the risk of all- cause mortality (Wald χ2=3.875, P=0.049). Conclusion
IDH is common, and its incidence varies using different definitions. Redefinition of IDH may reduce the variation. Using the UKKA guidelines, the risk of all-cause mortality increased with the frequency of IDH. Frequent IDH was significantly associated with all-cause mortality, which is closely related to clinical practice to reveal the association between IDH and all-cause mortality.
[1]Reeves P B, Mc C F.Mechanisms,Clinical Implications,and Treatment of Intradialytic Hypotension[J].Clin J Am Soc Nephrol, 2018, 13(8):1297-1303
[2]. K/DOQI clinical practice guidelines for cardiovascular disease in dialysis patients[J].American journal of kidney diseases, 2005, 4(45):1-153
[3]Kooman J, Basci A, Pizzarelli F, et al.EBPG guideline on haemodynamic instability[J].Nephrology Dialysis Transplantation, 2007, 22(Supplement 2):i22-i44
[4]Hirakata H, Nitta K, Inaba M, et al.Japanese Society for Dialysis Therapy Guidelines for Management of Cardiovascular Diseases in Patients on Chronic Hemodialysis[J].Therapeutic Apheresis and Dialysis, 2012, 16(5):387-435
[5]Mactier R, Hoenich Ph.D N,Breen CRenal Association Clinical Practice Guideline on Haemodialysis[J].Nephron Clinical Practice, 2011, 118(s1):c241-c286
[6]Kuipers J, Verboom L M, Ipema K J R, et al.The Prevalence of Intradialytic Hypotension in Patients on Conventional Hemodialysis: A Systematic Review with Meta-Analysis[J].American Journal of Nephrology, 2019, 49(6):497-506
[7]Flythe J E, Xue H, Lynch K E, et al.Association of mortality risk with various definitions of intradialytic hypotension[J].Journal of the American Society of Nephrology, 2015, 26(3):724-734
[8]Chou J A, Streja E, Nguyen D V, et al.Intradialytic hypotension,blood pressure changes and mortality risk in incident hemodialysis patients[J].Nephrology Dialysis Transplantation, 2018, 33(1):149-159
[9]Shoji T, Tsubakihara Y, Fujii M, et al.Hemodialysis-associated hypotension as an independent risk factor for two-year mortality in hemodialysis patients[J].Kidney Int, 2004, 66(3):1212-1220
[10]Yu J, Liu Z, Shen B, et al.Intradialytic Hypotension as an Independent Risk Factor for Long-Term Mortality in Maintaining Hemodialysis Patients: A 5-Year Follow-Up Cohort Study[J].Blood Purification, 2018, 45(4):320-326
[11] Desquilbet L, Mariotti F.Dose-response analyses using restricted cubic spline functions in public health research[J].Statistics in Medicine, 2010, 29(9):1037-1057
