Data_Sheet_1_Microalbuminuria After Kidney Transplantation Predicts Cardiovascular Morbidity.docx

Background: Microalbuminuria is a well-characterized marker of kidney malfunction, both in diabetic and non-diabetic populations, and is used as a prognostic marker for cardiovascular morbidity and mortality. A few studies implied that it has the same value in kidney transplanted patients, but the information relies on spot or dipstick urine protein evaluations, rather than the gold standard of timed urine collection.
Methods: We revisited a cohort of 286 kidney transplanted patients, several years after completing a meticulously timed urine collection and assessed the prevalence of major cardiovascular adverse events (MACE) in relation to albuminuria.
Results: During a median follow up of 8.3 years (IQR 6.4–9.1) 144 outcome events occurred in 101 patients. By Kaplan-Meier analysis microalbuminuria was associated with increased rate of CV outcome or death (p = 0.03), and this was still significant after stratification according to propensity score quartiles (p = 0.048). Time dependent Cox proportional hazard analysis showed independent association between microalbuminuria and CV outcomes 2 years following microalbuminuria detection (HR 1.83, 95% CI 1.07–2.96).
Conclusions: Two years after documenting microalbuminuria in kidney transplanted patients, their CVD risk was increased. There is need for primary prevention strategies in this population and future studies should address the topic.

背景：微量白蛋白尿（microalbuminuria）是糖尿病与非糖尿病人群中已被充分表征的肾功能异常标志物，同时亦被用作心血管疾病发病与死亡的预后标志物。已有少量研究提示其在肾移植患者中具有同等应用价值，但相关信息均基于随机尿或试纸法尿蛋白检测，而非金标准的计时留尿采集法。
方法：本研究对286名肾移植患者的队列进行了回顾性分析，该队列在数年前完成了严格规范的计时留尿采集，本研究评估了与白蛋白尿相关的主要心血管不良事件（major cardiovascular adverse events, MACE）的患病率。
结果：在中位随访8.3年（四分位间距（interquartile range, IQR）6.4~9.1）期间，101名患者共发生144例终点事件。经Kaplan-Meier分析显示，微量白蛋白尿与心血管事件或死亡的发生率升高相关（p=0.03）；按倾向得分（propensity score）四分位数分层后，该相关性仍具有统计学意义（p=0.048）。时间依赖性Cox比例风险分析显示，在检测到微量白蛋白尿2年后，微量白蛋白尿与心血管事件之间仍存在独立相关性（风险比（Hazard Ratio, HR）1.83，95%置信区间（Confidence Interval, CI）1.07~2.96）。
结论：在肾移植患者中确诊微量白蛋白尿2年后，其心血管疾病风险显著升高。该人群亟需采取一级预防策略，未来相关研究应围绕该主题展开。