Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Division of Nephrology, Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea.
Eur J Clin Invest. 2018 Jun;48(6):e12936. doi: 10.1111/eci.12936. Epub 2018 Apr 30.
IgA nephropathy (IgAN) is the most frequent primary glomerular disease and the leading cause of end-stage renal disease. We investigated clinicopathologic predictors of renal survival in patients with IgAN with a focus on glomerular filtration rate (GFR) decline slope.
We screened all patients with primary IgAN between 1995 and 2012. Renal progression was defined as doubling of serum creatinine. Using serial serum creatinine levels during the first-year, we calculated the GFR decline slopes. Further, we defined patients in the steepest GFR slope quartile as rapid decliners and those in the second steepest GFR slope quartile as slow decliners. Others were defined as nondecliners.
Of 214 participants, baseline GFR was 81 (62, 100) mL/min/1.73 m , which was not different among the 3 groups. Rapid decliners and slow decliners had higher levels of urinary protein/creatinine ratio (0.88, 0.89 and 0.58 g/gCr, respectively, P < .001). Five-year renal survival was 76% in rapid decliners, 91% in slow decliners and 100% in nondecliners (P < .001, rapid or slow decliners vs nondecliners). After adjustment for clinicopathologic variables, slow decliners were associated with an 8.8-fold higher risk of progression (P = .011), and rapid decliners were associated with a 10.2-fold increased risk of progression (P = .007) compared with nondecliners.
First-year GFR slope was associated with increased risk of renal progression, independent of proteinuria and histologic findings. Further studies are needed to investigate whether early GFR change can identify high-risk patients who benefit from immunosuppressive treatment in IgAN.
IgA 肾病（IgAN）是最常见的原发性肾小球疾病，也是导致终末期肾病的主要原因。我们研究了 IgAN 患者的临床病理预测因子，重点关注肾小球滤过率（GFR）下降斜率。
我们筛选了 1995 年至 2012 年间所有原发性 IgAN 患者。肾功能进展定义为血清肌酐加倍。我们使用第一年的连续血清肌酐水平计算 GFR 下降斜率。此外，我们将 GFR 斜率最快的四分位组患者定义为快速下降者，将 GFR 斜率第二快的四分位组患者定义为缓慢下降者，其余患者定义为无下降者。
在 214 名参与者中，基线 GFR 为 81（62，100）mL/min/1.73m，在 3 组之间无差异。快速下降者和缓慢下降者的尿蛋白/肌酐比值更高（分别为 0.88、0.89 和 0.58 g/gCr，P<0.001）。快速下降者的 5 年肾脏存活率为 76%，缓慢下降者为 91%，无下降者为 100%（P<0.001，快速或缓慢下降者与无下降者比较）。调整临床病理变量后，缓慢下降者进展的风险增加 8.8 倍（P=0.011），快速下降者进展的风险增加 10.2 倍（P=0.007）。
与蛋白尿和组织学发现无关，第一年 GFR 斜率与肾功能进展的风险增加相关。需要进一步研究早期 GFR 变化是否可以识别出需要免疫抑制治疗的 IgAN 高危患者。
