Prevalence of Interstitial Lung Abnormalities (ILA) in the general population and specific radiological patterns

Prevalence of Interstitial Lung Abnormalities (ILA) in the general population and specific radiological patterns <bold>Background:</bold> Interstitial Lung Abnormalities (ILA) indicate the presence of anomalous pulmonary findings incidentally found on chest computed tomography (CT) which can potentially progress over time towards an interstitial lung disease (ILD). <bold>Aim:</bold> We aimed to identify imaging patterns compatible with a diagnosis of ILA among radiological examinations performed for screening reasons or evaluation of other pathological conditions in the general population, and to correlate them with lung function impairment. <bold>Methods:</bold> Radiological examinations evaluated at the University Hospital of Palermo between October 2022 and September 2023 were retained for analysis. <bold>Results:</bold> A total of 185 cases of ILA were identified among 6300 radiological exams (2%). 41.2% showed a “subpleural fibrotic” radiological pattern, of which 8.8% already showing features of honeycombing; 54.4% elicited a “subpleural non-fibrotic” pattern, and 6.1% a “non-subpleural” radiological pattern. The complete functional tests of enrolled patients with “subpleural fibrotic” radiological pattern showed restrictive features and those with “non-subpleural” radiological pattern presented obstructive features. <bold>Conclusions:</bold> The current findings confirm that the rate of prevalence of ILA is unknown in the general population, and suggest the occurrence of an association between the specific imaging patterns and the lung function impairment. These results advocate for a more careful assessment of the radiological abnormalities suggestive of ILA.