Romano Giulio, Mioni Roberto, Danieli Nicola, Bertoni Martina, Croatto Elisa, Merla Lucia, Alcaro Lucia, Pedduzza Antonio, Metcalf Xenia, Rigamonti Alessandra, Catena Cristiana, Sechi Leonardo A, Colussi GianLuca
Nephrology, Department of Medicine, University of Udine, 33100 Udine, Italy.
Division of Nephrology, Academic Hospital of Udine "Santa Maria della Misericordia", 33100 Udine, Italy.
J Clin Med. 2022 May 25;11(11):2995. doi: 10.3390/jcm11112995.
Background. Intrarenal resistive index (RI) ≥ 0.80 predicts renal outcomes in proteinuric chronic kidney disease (CKD). However, this evidence in non-proteinuric patients with CKD of unknown etiology is lacking. In this study, we assessed the effect of intrarenal RI on renal function and all-cause mortality in non-proteinuric patients with CKD of unknown etiology despite an extensive diagnostic work-up. Methods. Non-proteinuric CKD patients were evaluated in a retrospective longitudinal study. Progression of renal disease was investigated by checking serum creatinine levels at 1, 3, and 5 years and defined by a creatinine level increase of at least 0.5 mg/dL. The discrimination performance of intrarenal RI in predicting the 5-year progression of renal disease was assessed by calculating the area under the receiver operating characteristic curve (AUROC). Results. One-hundred-thirty-one patients (76 ± 9 years, 56% males) were included. The median follow-up was 7.5 years (interquartile range 4.3−10.5) with a cumulative mortality of 53%, and 5-year renal disease progression occurred in 25%. Patients with intrarenal RI ≥ 0.80 had a faster increase of serum creatinine levels compared to those with RI < 0.80 (+0.06 mg/dL each year, 95% CI 0.02−0.10, p < 0.010). Each 0.1-unit increment of intrarenal RI was an independent determinant of 5-year renal disease progression (odds ratio 4.13, 95% CI 1.45−12.9, p = 0.010) and predictor of mortality (hazards ratio 1.80, 95% CI 1.05−3.09, p = 0.034). AUROCs of intrarenal RI for predicting 5-year renal disease progression and mortality were 0.66 (95% CI 0.57−0.76) and 0.67 (95% CI 0.58−0.74), respectively. Conclusions. In non-proteinuric patients with CKD of unknown etiology, increased intrarenal RI predicted both a faster decline in renal function and higher long-term mortality, but as a single marker, it showed poor discrimination performance.
背景。肾内阻力指数（RI）≥0.80可预测蛋白尿性慢性肾脏病（CKD）的肾脏预后。然而，病因不明的非蛋白尿性CKD患者缺乏这方面的证据。在本研究中，尽管进行了广泛的诊断检查，我们评估了肾内RI对病因不明的非蛋白尿性CKD患者肾功能和全因死亡率的影响。方法。在一项回顾性纵向研究中对非蛋白尿性CKD患者进行评估。通过检查1年、3年和5年时的血清肌酐水平来研究肾脏疾病的进展，肌酐水平至少升高0.5mg/dL定义为疾病进展。通过计算受试者操作特征曲线下面积（AUROC）来评估肾内RI预测肾脏疾病5年进展的判别性能。结果。纳入131例患者（76±9岁，56%为男性）。中位随访时间为7.5年（四分位间距4.3 - 10.5），累积死亡率为53%，25%的患者出现了5年肾脏疾病进展。与RI<0.80的患者相比，RI≥0.80的患者血清肌酐水平升高更快（每年+0.06mg/dL，95%CI 0.02 - 0.10，p<0.010）。肾内RI每增加0.1个单位是5年肾脏疾病进展的独立决定因素（比值比4.13，95%CI 1.45 - 12.9，p = 0.010）和死亡率的预测因素（风险比1.80，95%CI 1.05 - 3.09，p = 0.034）。肾内RI预测5年肾脏疾病进展和死亡率的AUROC分别为0.66（95%CI 0.57 - 0.76）和0.67（95%CI 0.58 - 0.74）。结论。在病因不明的非蛋白尿性CKD患者中，肾内RI升高预示着肾功能下降更快和长期死亡率更高，但作为单一标志物，其判别性能较差。
