血尿是免疫球蛋白A肾病(IgAN)最典型的表现;然而,其在疾病进展中的作用仍有争议。本研究旨在评估血尿与IgAN进展的关系。
回顾性队列研究。
在中国转诊医院接受治疗的1,333例IgAN患者的队列,中位随访时间为45个月。
使用全自动尿液颗粒分析仪(自动化方法)和熟练的检查人员进行尿沉渣检查(手动方法),在新鲜尿液中评估了血尿。血尿被表征为时变属性;即,随访期间每6个月计算每位患者的平均血尿水平.缓解定义为在随访的前6个月中平均红细胞计数≤5/高倍视野(手动方法)或≤28红细胞/μL(自动方法)。
估计肾小球穿透率下降50%或肾衰竭发展的复合事件。
多变量原因特异性危险模型分析血尿与复合肾脏疾病进展事件之间的关系.
随访期间随时间变化的血尿是复合肾脏疾病进展事件的独立危险因素(HR,1.46;95%CI,1.13-1.87;P=0.003)。诊断后6个月内血尿缓解与复合肾脏疾病进展事件的发生率显着降低相关(HR,0.41;95%CI,0.28-0.61;P<0.001)。在前6个月中,蛋白尿的缓解和血尿的缓解之间存在显着交互作用(P<0.001)。血尿缓解与肾脏疾病进展之间的关联是可检测的(HR,0.46;95%CI,0.32-0.68)在持续性蛋白尿(前6个月蛋白质排泄>1.0g/d)的亚群内,但在蛋白尿缓解的患者中没有(HR,0.64;95%CI,0.31-1.29;P=0.2)。2种血尿评价技术呈强烈且显著的线性相关(r=0.948;P<0.001),使用这两种方法的结果是一致的。
单中心回顾性研究。包含时变协变量的比例风险回归可能会产生时变混杂。没有直接评估血尿减少的预测价值。
血尿水平与肾脏疾病进展独立相关,而在持续性蛋白尿患者中,血尿缓解与IgAN肾脏结局改善相关.此外,为了监测IgAN进展,自动评估血尿的方法有望替代手动评估尿沉渣。
Hematuria is the most typical presentation of immunoglobulin A nephropathy (IgAN); however, its role in disease progression is still controversial. This study aimed to evaluate the association of hematuria and progression of IgAN.
Retrospective cohort study.
A cohort of 1,333 patients with IgAN treated at a Chinese referral hospital with a median follow-up of 45 months.
Microhematuria was evaluated in fresh urine using a fully automated urine particle analyzer (automated method) and urine sediment examination by a skilled examiner (manual method). Hematuria was characterized as a time-varying attribute; namely, average hematuria level was calculated for every 6-month period for each patient during follow-up. Remission was defined as average red blood cell count ≤5/high-power field (manual method) or ≤28 red blood cells/μL (automated method) during the first 6 months of follow-up.
Composite event of 50% decline in estimated glomerular filtration rate or development of kidney failure.
Multivariable cause-specific hazards models to analyze the relationship between hematuria and the composite kidney disease progression event.
Time-varying hematuria during follow-up was an independent risk factor for the composite kidney disease progression event (HR, 1.46; 95% CI, 1.13-1.87; P = 0.003). Hematuria remission during the 6 months after diagnosis was associated with a significantly lower rate of the composite kidney disease progression event (HR, 0.41; 95% CI, 0.28-0.61; P < 0.001). A significant interaction was detected between remission of proteinuria and remission of hematuria during the first 6 months (P < 0.001). The association between remission of hematuria and kidney disease progression was detectable (HR, 0.46; 95% CI, 0.32-0.68) within the subpopulation with persistent proteinuria (protein excretion > 1.0 g/d during the first 6 months), but not among patients whose proteinuria had remitted (HR, 0.64; 95% CI, 0.31-1.29; P = 0.2). The 2 techniques for hematuria evaluation were strongly and significantly linearly correlated (r = 0.948; P < 0.001), and results using these 2 methods were consistent.
A single-center retrospective study. Proportional hazards regression incorporating time-varying covariates may create time-varying confounding. The predictive value of reductions in hematuria was not directly evaluated.
Level of hematuria was independently associated with kidney disease progression, whereas hematuria remission was associated with improved kidney outcomes in IgAN among patients with persistent proteinuria. Additionally, to monitor IgAN progression, automated methods to evaluate hematuria hold promise as a replacement for manual evaluation of urinary sediment.