Nishikiori Hirotaka, Chiba Hirofumi, Lee Sang Hoon, Kondoh Shun, Kamo Ken-Ichi, Nakamura Koshi, Ikeda Kimiyuki, Kuronuma Koji, Chung Man Pyo, Kondoh Yasuhiro, Homma Sakae, Inase Naohiko, Park Moo Suk, Takahashi Hiroki
Department of Respiratory Medicine and Allergology, Sapporo Medical University School of Medicine, Japan.
Division of Pulmonology, Department of Internal Medicine, Severance Hospital, Institute of Chest Diseases, Yonsei University College of Medicine, Republic of Korea.
Respir Investig. 2020 Sep;58(5):395-402. doi: 10.1016/j.resinv.2020.04.001. Epub 2020 Jul 24.
The easy-to-calculate gender, age, and lung physiology (GAP) model shows good predictive and discriminative performance in the prognosis of idiopathic pulmonary fibrosis (IPF). However, the GAP model was not effective in predicting the prognosis accurately in previous Japanese and Korean IPF cohort studies. Therefore, we developed a modified GAP model for the East-Asian populations by weighing the GAP variables. The validity of the modified GAP model was subsequently evaluated in East-Asian IPF patients.
The derivation cohort comprised 326 patients with IPF. Weights of the variables were adjusted on the basis of coefficients derived from Cox regression models. The total points were distributed to the three stages of the disease so that the number of patients included in each stage was appropriate. The validity of the modified model was analyzed in another Japanese cohort of 117 patients with IPF and a nationwide cohort of Korean patients with IPF.
Predicted survival rates differed significantly in the derivation cohort using the modified GAP model for each stage of IPF (log-rank test: stage I vs. stage II, p < 0.001; stage II vs. stage III, p < 0.001). Model performance improved according to Harrell's C-index (at three years: 0.696 in the original GAP model to 0.738 in the modified model). The performance of the modified model was validated in the Japanese validation and Korean national cohorts.
Our modification of the original GAP model showed improved performance in East-Asian IPF patient populations.
易于计算的性别、年龄和肺生理学（GAP）模型在特发性肺纤维化（IPF）的预后评估中显示出良好的预测和判别性能。然而，在先前的日本和韩国IPF队列研究中，GAP模型在准确预测预后方面并不有效。因此，我们通过对GAP变量进行加权，为东亚人群开发了一种改良的GAP模型。随后在东亚IPF患者中评估了改良GAP模型的有效性。
推导队列包括326例IPF患者。根据Cox回归模型得出的系数调整变量的权重。将总分分配到疾病的三个阶段，以使每个阶段纳入的患者数量合适。在另一个由117例IPF患者组成的日本队列和一个韩国IPF患者全国队列中分析改良模型的有效性。
在推导队列中，使用改良GAP模型对IPF各阶段的预测生存率有显著差异（对数秩检验：I期与II期，p < 0.001；II期与III期，p < 0.001）。根据Harrell's C指数，模型性能有所改善（三年时：原始GAP模型为0.696，改良模型为0.738）。改良模型的性能在日本验证队列和韩国全国队列中得到了验证。
我们对原始GAP模型的改良在东亚IPF患者群体中表现出更好的性能。
