Supplementary Material for: Relationships among non-neoplastic histopathological features, kidney function, proteinuria, and other clinical factors in patients undergoing nephrectomy.

Introduction. The non-neoplastic kidney parenchyma from nephrectomies is often overlooked in routine examination. We aimed to evaluate the associations between global glomerulosclerosis (GS), interstitial fibrosis (IF) or arteriosclerosis (AS), with estimated glomerular filtration rate (eGFR), dipstick proteinuria, and other clinical factors. Methods. We performed a cross-sectional analysis of 781 patients with nephrectomy. We used regression models with and without interaction factors. The tested exposures were GS, IF or AS and the outcome measures were GFR and dipstick proteinuria. Results In multivariable analyses, increasing degrees of GS, IF, or AS were significantly associated with lower eGFR and proteinuria (p<0.05 for each). Obesity and hypertension (HTN) modified the association between eGFR and degrees of GS whereas proteinuria and cardiovascular disease (CVD) modified the association between eGFR and degrees of AS (p for interaction <0.05). Compared with GS <10%, GS >50% was associated with lower eGFR in patients with (-45 ml/min/1.73m2) than without (-19 ml/min/1.73m2) obesity; and GS >50% was associated with lower eGFR in patients with (-31 ml/min/1.73m2) than without (-16 ml/min/1.73m2) HTN. Compared with AS < 26%, AS >50% was associated with lower eGFR in patients with (-11 ml/min/1.73m2) than without (-6 ml/min/1.73m2) proteinuria; and AS >50% was associated with lower eGFR in patients with (-23 ml/min/1.73m2) than without (-7 ml/min/1.73m2) CVD. Conclusion. Greater degrees of each GS, IF, and AS are independently associated with proteinuria and lower eGFR. Obesity, HTN, proteinuria, and CVD modify the relationship between eGFR and specific histopathological features of nephrosclerosis.

引言：常规临床检查中，肾切除术获取的非肿瘤性肾实质样本常被忽视。本研究旨在探讨全球肾小球硬化（global glomerulosclerosis, GS）、间质纤维化（interstitial fibrosis, IF）或动脉硬化（arteriosclerosis, AS）与估算肾小球滤过率（estimated glomerular filtration rate, eGFR）、试纸法蛋白尿及其他临床因素之间的关联。方法：本研究对781例接受肾切除术的患者开展横断面分析，分别构建含交互因子与不含交互因子的回归模型。研究暴露因素为GS、IF或AS，结局指标为eGFR与试纸法蛋白尿。结果：多变量分析显示，GS、IF或AS的病变程度加重均与eGFR降低及蛋白尿水平升高显著相关（各项分析p均<0.05）。肥胖与高血压（hypertension, HTN）可调节eGFR与GS病变程度之间的关联，而蛋白尿与心血管疾病（cardiovascular disease, CVD）可调节eGFR与AS病变程度之间的关联（交互项p均<0.05）。以GS<10%的患者为参照，GS>50%的肥胖患者eGFR较非肥胖患者降低更显著（分别降低45 ml/min/1.73m²与19 ml/min/1.73m²）；GS>50%的高血压患者eGFR较非高血压患者降低更显著（分别降低31 ml/min/1.73m²与16 ml/min/1.73m²）。以AS<26%的患者为参照，AS>50%的蛋白尿患者eGFR较非蛋白尿患者降低更显著（分别降低11 ml/min/1.73m²与6 ml/min/1.73m²）；AS>50%的心血管疾病患者eGFR较非心血管疾病患者降低更显著（分别降低23 ml/min/1.73m²与7 ml/min/1.73m²）。结论：GS、IF及AS的病变程度加重均独立相关于蛋白尿水平升高与eGFR降低。肥胖、HTN、蛋白尿与CVD可调节eGFR与肾硬化特异性组织病理学特征之间的关联。