P3 Progression of early fibrotic ILA to established interstitial lung disease and mortality: observations from a regional centre

Abstract

P3 Table 1 Univariate and multivariate cox regression analysis for outcome of mortality. Hazard ratios of ILD categories are expressed relative to Nil ILD group Table 1. Outcome = Mortality Univariate Multivariate Covariate n Death HR Lower Upper Sig. HR Lower Upper Sig. Age – – 1.02 1.01 1.04 0.0001* 1.02 1.01 1.04 0.002* Gender – – 1.14 0.95 1.37 0.140 1.08 0.89 1.31 0.420 Nil ILD (ref. category) 355 (13.0%) 43 (12.1%) – – – <0.001* – – – <0.001* GGO only 279 (10.2%) 54 (19.3%) 1.67 1.12 2.50 0.011* 1.63 1.09 2.43 0.017* Reticulation only 603 (22.0%) 68 (11.3%) 1.09 0.74 1.59 0.667 1.01 0.69 1.48 0.966 Reticulation + GGO 373 (13.6%) 55 (14.7%) 1.43 0.96 2.13 0.079 1.39 0.93 2.07 0.108 Reticulation + Emph 133 (4.9%) 28 (2.1%) 2.32 1.45 3.71 <0.001* 2.08 1.29 3.35 0.003* Retic + GGO + Emph 150 (5.5%) 27 (18.0%) 1.74 1.07 2.81 0.025* 1.67 1.03 2.70 0.038* Probable UIP 490 (17.9%) 86 (17.5%) 1.58 1.10 2.28 0.014* 1.45 1.01 2.11 0.047* Definite UIP 272 (9.9%) 87 (32.0%) 2.82 1.95 4.10 <0.001* 2.55 1.76 3.69 <0.001* * P<0.05. GGO; ground glass opacities, UIP; Usual interstitial pneumonia, Emph; Emphysema. Poster sessions A68 Thorax 2021;76(Suppl 2):A1–A205 on N ovem er 3, 2021 by gest. P rocted by coright. httphorax.bm jcom / T hrax: frst pulished as 10.113orax-2021-B T S abscts.114 on 8 N ovem er 221. D ow nladed fom Background Early detection and treatment of lung cancer through lowdose computed tomography (LDCT) screening reduces lung cancer mortality. Undiagnosed interstitial lung disease (ILD) can be incidentally detected on LDCT, but whether this leads to improved clinical outcomes is unclear. Methods The West London lung screening pilot invited eversmokers aged 55–75 for a lung health check, and LDCT for those meeting a prespecified lung cancer risk score. LDCTs were reported by 5 consultant thoracic radiologists with 8 years thoracic CT experience. Participants without known ILD and with (i) >10% interstitial lung abnormalities (ILAs) as defined by the Fleischner Society on LDCT (ii) 5–10% ILAs on LDCT and restrictive spirometry (pre-March 2020), (iii) ILAs >5% (without spirometry post-March 2020), (iv) progressive ILAs on serial imaging performed after 12–24 months, were referred for clinical evaluation to the ILD Unit at the Royal Brompton Hospital. Diagnoses were assigned after multidisciplinary team (MDT) discussion. Results ILAs of >5% extent on LDCT were identified in 39/ 1853 (2.1%) subjects screened between August 2018 and April 2021 (table 1). Respiratory symptoms were present in 18/39 (46.1%) and crackles were auscultated in 17 of 22 subjects (77.3%) undergoing physical examination. Past exposure to potential environmental triggers was noted in 21/39 (53.8%). Diagnostic bronchoalveolar lavage was performed in 7/39 (17.9%) and one patient underwent transbronchial lung cryobiopsy. After MDT discussion, ILD was concluded in 31/39 (79.5%) cases, of which 14/31 (45.2%) were diagnosed with IPF. In the IPF subgroup, antifibrotics were initiated in 7/14 (50%) of cases. In those diagnosed with other ILDs, immunomodulatory treatment was initiated in 2/25 (8%) subjects. Conclusion A large proportion of individuals with newly identified ILAs have an abnormal clinical examination and respiratory symptoms, consistent with the widely held suspicion that ILD is underdiagnosed in the community. Lung cancer screening in this demographic provides a unique opportunity to address this unmet health metric. Earlier identification of ILD, specifically IPF, allows institution of antifibrotic therapies proven to modify the natural history of the disease by preserving lung function and extending life. The cost-effectiveness of this approach for ILD screening warrants detailed evaluation. P5 HOW SHOULD PATIENTS WITH INTERSTITIAL LUNG ABNORMALITIES BE EVALUATED AND MONITORED? EXPERIENCE FROM A SECONDARY CARE INTERSTITIAL LUNG DISEASE CLINIC SL Liew, J Shaw, C Hayton, Z Borrill, G Ng Man Kwong. Royal Oldham Hospital, Manchester, UK; Wythenshawe Hospital, Manchester, UK; North Manchester General Hospital, Manchester, UK 10.1136/thorax-2021-BTSabstracts.115 Introduction Interstitial lung abnormalities (ILA) have been defined as incidental radiological parenchymal abnormalities without clinical suspicion of interstitial lung disease (ILD). It is recognised that they are clinically important due to increased risk of pulmonary fibrosis, exercise impairments and mortality. A recently published Fleischner Society position paper described three subcategories of ILA; non-subpleural, subpleural non-fibrotic and subpleural fibrotic. Little is known about the real world management of these patients. Methods We performed a retrospective analysis of an ILD database containing 1298 patients covering a population of 820,000. Results 55 patients with ILA were identified (61.8% male, median age 75 (IQR 69.5–79), current or ex-smokers 70.9%). 33/55(60%) were categorized as subpleural fibrotic, 15/55 (27.2%) as subpleural non-fibrotic and 7/55(12.7%) as nonsubpleural. Baseline pulmonary function showed a mean (S.D.) FVC% predicted of 98.76% (±19.94) and TLCO% predicted of 59.45%(±23.45). 42/55(76.3%) patients were followed up and 13/55(23.7%) were discharged with safety netting after initial consultation. A further 26 were discharged after a period of follow up (mean (S.D) 18.5(26.3) months). 16/55(29.1%) remain under active follow up, mean duration 22.3 months. 1 patient was rereferred after discharge. 11 (20%) patients died within 3 years of ILA identification. In those who died, there was no significant difference in age, co-morbidities or baseline pulmonary function compared to survivors. Cause of death was known in 7/11, one caused by lung cancer, none by ILD. 6/42(14.3%) reported worsening respiratory symptoms during the follow-up period. 27/42 patients had serial pulmonary function available at 12 months, of which 3(11.1%) had >10% decline in FVC. 23 had repeat Abstract P4 Table 1 Characteristics of the subjects Characteristics Subjects with ILAs