Department of Clinical research and Data management, Center of Respiratory Medicine, China-Japan Friendship Hospital; National Center for Respiratory Medicine; Institute of Respiratory Medicine, Chinese Academy of Medical Sciences; National Clinical Research Center for Respiratory Diseases, Beijing, China.
Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, China-Japan Friendship Hospital; National Center for Respiratory Medicine; National Clinical Research Center for Respiratory Diseases; Institute of Respiratory Medicine, Chinese Academy of Medical Science, Peking Union Medical College, Beijing, China.
Clin Respir J. 2023 Sep;17(9):831-840. doi: 10.1111/crj.13564. Epub 2022 Nov 27.
The GAP model was widely used as a simple risk "screening" method for patients with idiopathic pulmonary fibrosis (IPF).
We sought to validate the GAP model in Chinese patients with IPF to evaluate whether it can accurately predict the risk for mortality.
A total of 212 patients with IPF diagnosed at China-Japan Friendship Hospital from 2015 to 2019 were enrolled. The latest follow-up ended in September 2022. Cumulative mortality of each GAP stage was calculated and compared based on Fine-Gray models for survival, and lung transplantation was treated as a competing risk. The performance of the model was evaluated in terms of both discrimination and calibration.
The cumulative mortality in patients with GAP stage III was significantly higher than that in those with GAP stage I or II (Gray's test p < 0.0001). The Harrell c-index for the GAP calculator was 0.736 (95% CI: 0.667-0.864). The discrimination for the GAP staging system were similar with that for the GAP calculator. The GAP model overestimated the mortality rate at 1- and 2-year in patients classified as GAP stage I (6.90% vs. 1.77% for 1-year, 14.20% vs. 6.78% for 2-year).
Our findings indicated that the GAP model overestimated the mortality rate in mild group.
GAP 模型被广泛用作特发性肺纤维化（IPF）患者的简单风险“筛查”方法。
我们试图在中国的 IPF 患者中验证 GAP 模型，以评估其是否能准确预测死亡率。
共纳入 2015 年至 2019 年在中国中日友好医院诊断为 IPF 的 212 例患者。随访截止到 2022 年 9 月。基于 Fine-Gray 模型对生存进行计算，比较每个 GAP 阶段的累积死亡率，并将肺移植作为竞争风险。从区分度和校准度两个方面评价模型的性能。
GAP 分期 III 期患者的累积死亡率明显高于 GAP 分期 I 期或 II 期（Gray 检验 p<0.0001）。GAP 计算器的 Harrell c 指数为 0.736（95%CI：0.667-0.864）。GAP 分期系统的区分度与 GAP 计算器相似。对于 GAP 分期 I 期患者，GAP 模型高估了 1 年和 2 年的死亡率（6.90%比 1 年的 1.77%，14.20%比 2 年的 6.78%）。
我们的研究结果表明，GAP 模型高估了轻度组的死亡率。
