Predictive role of Oxford Classification for prognosis in children with IgA nephropathy: a systematic review and meta-analysis

The Oxford Classification was proposed as an independent prognostic indicator in IgA nephropathy (IgAN). However, most studies on the subject focus on adults instead of children. Using a meta-analysis to appraise the predictive roles of the Oxford classification for the prognosis of pediatric patients with IgAN. All cohort studies regarding the analysis of the association between poor kidney-related prognosis (GFR categories G2-G5) according to the Kidney Disease Improving Global Outcomes (KDIGO) Guideline in pediatric patients with IgAN and five pathologic lesions in the Oxford Classification were included. Hazard ratios (HRs) regarding the association between the Oxford classification and prognosis of pediatric patients with IgAN were synthesized using random effect models. The risk of bias in studies was assessed based on the Newcastle-Ottawa scale. Fourteen articles were included with 5679 IgAN patients and 710 endpoint outcome events occurred. M1 was associated with a higher risk of poor kidney-related prognosis compared with M0, pooled HR (1.79; 95%CI, 1.46–2.19; <i>p</i> &lt; 0.001, random effect model). S1 and T1 or T2 increased the risk of poor kidney-related prognosis (pooled HR, 2.13; 95%CI, 1.68–2.70; <i>p</i> &lt; 0.001; pooled HR, 2.64; 95%CI, 1.81–3.86; <i>p</i> &lt; 0.001, respectively, estimated by random effect model). Compared with C0, C1, or C2 was also associated with an increased risk of poor kidney-related prognosis in the subgroup analysis of Asian and other populations. Evidence to indicate that E1 increased the risk of poor kidney-related prognosis was marginal.

牛津分型（Oxford Classification）最初被提出作为IgA肾病（IgA nephropathy, IgAN）的独立预后指标。然而，目前该领域的多数研究均聚焦于成人患者，而非儿童群体。本研究通过荟萃分析，评估牛津分型对儿童IgAN患者的预后预测价值。本研究纳入所有队列研究，这些研究均分析了儿童IgAN患者中，依据改善全球肾脏病预后组织（Kidney Disease Improving Global Outcomes, KDIGO）指南定义的不良肾脏相关预后（肾小球滤过率GFR分级G2-G5）与牛津分型的5种病理病变之间的关联。采用随机效应模型合并牛津分型与儿童IgAN患者预后关联的风险比（Hazard Ratios, HRs），并采用纽卡斯尔-渥太华量表（Newcastle-Ottawa scale）评估纳入研究的偏倚风险。最终纳入14项研究，共涉及5679例IgAN患者，累计发生710例终点事件。与M0亚型相比，M1亚型患者的不良肾脏相关预后风险显著升高，合并风险比为1.79（95%置信区间[CI]：1.46~2.19；*p*<0.001，随机效应模型）。S1亚型、T1或T2亚型均会升高不良肾脏相关预后风险：合并风险比分别为2.13（95%CI：1.68~2.70；*p*<0.001）与2.64（95%CI：1.81~3.86；*p*<0.001，均采用随机效应模型估算）。在亚洲人群及其他人群的亚组分析中，与C0亚型相比，C1或C2亚型同样与不良肾脏相关预后风险升高相关。现有证据提示E1亚型升高不良预后风险的结果尚不明确。