Association of the lung immune prognostic index with the survival of patients with idiopathic interstitial pneumonias

• Published in: Respirology (Carlton, Vic.) Vol. 29; no. 2; pp. 136 - 145
• Main Authors: Suzuki, Takahito, Karayama, Masato, Aoshima, Yoichiro, Mori, Kazutaka, Yoshizawa, Nobuko, Ichikawa, Shintaro, Kato, Shinpei, Yokomura, Koshi, Kono, Masato, Hashimoto, Dai, Inoue, Yusuke, Yasui, Hideki, Hozumi, Hironao, Suzuki, Yuzo, Furuhashi, Kazuki, Fujisawa, Tomoyuki, Enomoto, Noriyuki, Goshima, Satoshi, Inui, Naoki, Suda, Takafumi
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.02.2024; Wiley Subscription Services, Inc
• Subjects: Fibrosis; Humans; idiopathic interstitial pneumonia; Idiopathic Interstitial Pneumonias; Idiopathic Pulmonary Fibrosis; Immune status; interstitial lung disease; L-Lactate dehydrogenase; lactate dehydrogenase; Leukocytes (neutrophilic); Lung; Lung diseases; Lymphocytes; neutrophil‐to‐lymphocyte ratio; Pneumonia; Prognosis; Retrospective Studies; lactate dehydrogenase; neutrophil-to-lymphocyte ratio; idiopathic pulmonary fibrosis; interstitial lung disease; idiopathic interstitial pneumonia
• ISSN: 1323-7799; 1440-1843; 1440-1843
• DOI: 10.1111/resp.14621

Background and Objective The lung immune prognostic index (LIPI), a simple index calculated from the blood lactate dehydrogenase level and derived neutrophil‐to‐lymphocyte ratio, is thought to be associated with host immune status. However, the utility of LIPI in patients with idiopathic interstitial pneumonias (IIPs) is unknown. Methods In this multicentre, retrospective, observational study, an association between LIPI and the survival of patients with IIPs was evaluated. Results Exploratory and validation cohorts consisting of 460 and 414 patients with IIPs, respectively, were included (159 and 159 patients had idiopathic pulmonary fibrosis [IPF], and 301 and 255 had non‐IPF, respectively). In the exploratory cohort, patients with IPF and a low LIPI had significantly better survival than those with a high LIPI (median of 5.6 years vs. 3.9 years, p = 0.016). The predictive ability of LIPI for the survival of patients with IPF was validated in the validation cohort (median of 8.5 years vs. 4.4 years, p = 0.003). In a multivariate Cox proportional hazard analysis, LIPI was selected as an independent predictive factor for the survival of IPF patients. There was no significant association between LIPI and survival of non‐IPF patients in the exploratory and validation cohorts. Conclusion The LIPI was a predictive factor for the survival of patients with IPF and could aid the management of IPF. The lung immune prognostic index (LIPI), composed of white blood cell and neutrophil counts, and lactate dehydrogenase levels, is predictive for the prognosis of patients with IPF. The LIPI, a simple index readily calculated from a routine blood test, can provide useful information for the management of patients with IPF.