RADIOGRAPHIC EMPHYSEMA PREDICTS INTERSTITIAL LUNG ABNORMALITIES IN SMOKING PATIENTS UNDERGOING LOBECTOMY

TYPE: Abstract TOPIC: Diffuse Lung Disease PURPOSE: Interstitial Lung Abnormalities (ILAs) are radiographic incidental findings seen in smokers and are associated with increased risk of histological fibrosis and mortality. The present study aims to detect the prevalence of subclinical radiographic ILA/ILD, its predictors and its impact on mortality in a rural Appalachian population. METHODS: Patients (n=353) who underwent lobectomy for lung nodule or mass were retrospectively identified (years 2017 to 2020). CT chest were reviewed for characterization of ILA, ILD and emphysema. Demographics, comorbidities and PFT findings were collected. RESULTS: Radiographic subclinical ILA and ILD patterns (Table 1) were observed in 53% patients, whereas only 1.1% patients (n=4) had clinical diagnosis of ILA/ILD prior to surgery. Study cohort had mean age of 66.07+10.19 years, female predominance (57%) and was overweight (mean BMI 28.30+6.87 kg/m2). 90% patients were ever-smokers with mean pack-years of 44.4+31.9. Most prevalent co-morbidities included hypertension (69.7%), hyperlipidemia (59.6%) and acid reflex (40.8%). 70.5% patients had radiographic emphysema. Mean % predicted values for FEV1, FVC and DLCO were 76.9+21.8, 86+17.7, and 68.7+22.2, respectively. Presence of radiographic emphysema and isolated bronchiectasis and lower FEV1 predicted ILA and/or ILD whereas CT findings of ILA/ILD, emphysema and isolated honeycombing were associated with increased mortality in the cohort. CONCLUSIONS: Subclinical ILA/ILD was widely prevalent in smokers. Radiographic emphysema is a strong predictor of ILA/ILD. ILA/ILD was associated with increased mortality in our cohort. CLINICAL IMPLICATIONS: In heavy smoking population, presence of emphysema can predict presence of radiographic ILA/ILD. Smoking related non-malignant lung injuries can co-exist without clinical manifestations. DISCLOSURE: Nothing to declare. KEYWORD: Interstitial Lung Abnormalities