RT Journal Article SR Electronic T1 Body mass index and in-hospital mortality in patients with acute exacerbation of idiopathic pulmonary fibrosis JF ERJ Open Research JO erjor FD European Respiratory Society SP 00037-2021 DO 10.1183/23120541.00037-2021 A1 Nobuyasu Awano A1 Taisuke Jo A1 Hideo Yasunaga A1 Minoru Inomata A1 Naoyuki Kuse A1 Mari Tone A1 Kojiro Morita A1 Hiroki Matsui A1 Kiyohide Fushimi A1 Takahide Nagase A1 Takehiro Izumo YR 2021 UL http://openres.ersjournals.com/content/early/2021/04/15/23120541.00037-2021.abstract AB Background Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease characterised by chronic fibrosis, and acute exacerbation of IPF (AE-IPF) is the leading cause of death in patients with IPF. Data on the association between the body mass index (BMI) and prognosis of AE-IPF are lacking. This study was performed to evaluate the association between the BMI and in-hospital mortality in patients who developed AE-IPF using a national inpatient database.Methods Using the Japanese Diagnosis Procedure Combination database, we retrospectively collected data of inpatients with AE-IPF from July 1, 2010 to March 31, 2018. We performed a multivariable logistic regression analysis to evaluate the association between all-cause in-hospital mortality and the BMI, categorised as underweight (<18.5 kg·m−2), low-normal weight (18.5–22.9 kg·m−2), high-normal weight (23.0–24.9 kg·m−2), overweight (25.0–29.9 kg·m−2), and obese (≥30.0 kg·m−2).Results In total, 14,783 patients were eligible for this study. The in-hospital mortality rate was 59.0%, 55.0%, 53.8%, 54.8%, and 46.0% in the underweight, low-normal weight, high-normal weight, overweight, and obese groups, respectively. Underweight patients had a significantly higher mortality rate (odds ratio, 1.25; 95% confidence interval, 1.10–1.42) and obese patients had a significantly lower mortality rate (odds ratio, 0.71; 95% confidence interval, 0.54–0.94) than low-normal weight patients.Conclusion Among patients with AE-IPF, the underweight group had higher mortality and the obese group had lower mortality.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Dr. Awano has nothing to disclose.Conflict of interest: Dr. Jo has nothing to disclose.Conflict of interest: Dr. Yasunaga reports grants from The Ministry of Health, Labour and Welfare, Japan, grants from The Ministry of Education, Culture, Sports, Science and Technology, Japan, during the conduct of the study.Conflict of interest: Dr. Inomata has nothing to disclose.Conflict of interest: Dr. Kuse has nothing to disclose.Conflict of interest: Dr. Tone has nothing to disclose.Conflict of interest: Dr. Morita has nothing to disclose.Conflict of interest: Dr. Matsui has nothing to disclose.Conflict of interest: Dr. Fushimi has nothing to disclose.Conflict of interest: Dr. Nagase has nothing to disclose.Conflict of interest: Dr. Izumo has nothing to disclose.