RT Journal Article
SR Electronic
T1 Improved spirometric index to discriminate the severity of centrilobular emphysema
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP PA1859
DO 10.1183/13993003.congress-2021.PA1859
VO 58
IS suppl 65
A1 Takafumi Shimada
A1 Hiroaki Iijima
A1 Yusuke Shiraishi
A1 Fumi Mochizuki
A1 Takashi Naito
A1 Hiroshi Shima
A1 Kunihiko Terada
A1 Susumu Sato
A1 Shigeo Muro
A1 Toyohiro Hirai
A1 Nobuyuki Hizawa
A1 Naoya Tanabe
YR 2021
UL http://erj.ersjournals.com/content/58/suppl_65/PA1859.abstract
AB Introduction/Aims: Obstructive Index (OI) is a spriometic index that reflects the shape of the maximal expiratory flow-volume (MEFV) curve. A previous study showed that OI reflects the concavity of the MEFV curve and the extent of emphysema (Mochizuki et al., Sci Rep 9, 13159, 2019). However, the association of OI with emphysema subtypes such as centrilobular emphysema (CLE) and paraseptal emphysema (PSE) has not yet been elucidated. This study aimed to investigate whether OI could reflect the severity of CLE and PSE.Methods: This study retrospectively analyzed 917 subjects who underwent chest computed tomography (CT) and spirometry at three different facilities, namely, a medical checkup center (Tsukuba Medical Center, N=420), clinic (Terada Clinic, N=328), and university hospital (Kyoto University, N=169). The presence and severity of CLE and PSE on CT were assessed visually based on the Fleischner Society’s classification system. The OI was Box-Cox transformed for normalization and adjusted using least-squares mean regression. Tukey’s honest significant difference test was used for multiple comparisons.Results: In subjects without PSE, OI increased with the severity grade of CLE (adjusted mean of Box-Cox transformed OI; absent: 2.08; trace: 2.14; mild: 2.22; moderate: 2.78; confluent: 2.90; advanced: 3.73). OI in subjects with moderate, confluent, and advanced CLE was significantly higher than that in those without CLE (all P <0.001). In contrast, OI did not differ among the different grades of PSE (absent, 2.07; mild, 2.09, and substantial, 2.06) in subjects without CLE.Conclusions: OI could be useful as a biomarker to discriminate the severity of CLE.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA1859.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).