Modified GAP stage as a predictor of acute exacerbation in idiopathic pulmonary fibrosis

Introduction: We have previously shown that the GAP stage was useful for predicting an acute exacerbation of IPF (AE-IPF). However, the discriminative ability between GAP stages I and II was insufficient. Aims: To investigate whether a modified GAP score which includes KL-6 and the ethnicity has a better accuracy for predicting the risk of AE-IPF. Methods: A total of 131 patients with IPF (75 German and 56 Japanese) were studied. Baseline serum KL-6 levels >1,300 U/mL and Results: The original GAP score at baseline was 4.5±0.2 in the German and 4.3±0.2 in the Japanese cohorts (p=0.50). The modified GAP score at baseline was 4.8±0.2 in the German and 6.9±0.3 in the Japanese cohorts (p Conclusions: The modified GAP score/stage which includes baseline serum KL-6 level and Japanese ethnicity demonstrated a higher accuracy for predicting AE-IPF than the original GAP stage during the first 3 years of follow-up.