{
  "abstract": "Introduction Interstitial Lung Abnormalities (ILAs) are subtle lung parenchymal changes on CT scans, characterised by reticular patterns, ground-glass opacifications (GGO), and traction bronchiectasis. They represent early lung changes and may precede the development of Interstitial lung Disease (ILD). The timeline for progression remains unclear.Rationale Our study aims to retrospectively evaluate initial lung changes in patients with confirmed ILD, to determine the average time for progression to ILD, and assess how factors such as age, gender, and smoking status influence progression rate and disease severity.Method Retrospective cohort study of patients reviewed in the ILD MDT at a tertiary academic ILD unit between April 2024 – March 2025. 498 patients were discussed at MDT, of whom 223 were formally diagnosed with ILD. Inclusion criteria required patients to have undergone at least 1 Chest CT within the 10 years preceding their MDT discussion. Patients with Smoking related-ILD and CTD-ILD were excluded, as their progression is better understood. For the remaining patients, the earliest scan showing ILA in the 10 years prior to diagnosis was identified. Scans showing established fibrosis at this earliest time point were excluded from further analysis, leaving a cohort of 39 patients.Results In this cohort, 36% were female and 64% male. Most (62%) were ex-smokers, with pack-years ranging from 5 to 92; 20.5% were non-smokers. The most common early CT finding was subpleural reticulations (64%), followed by combined reticulations and GGOs (23%) and isolated GGOs (13%). Progression time from ILA to ILD varied by initial CT findings: GGOs progressed in 29 months, a combination of subpleural reticulations and GGOs progressed in 39 months and subpleural reticulations alone progressed to ILD in 47 months. The average time to progression was 42.6 months.Abstract S153 Figure 1Conclusion No current established guidelines exist for monitoring ILAs. Patients are often discharged back to primary care and re-evaluated only after respiratory symptoms develop, by which time fibrosis is often advanced. This study highlights the poorly characterised progression timeline of ILAs to ILD and suggests that regular surveillance, including annual high-resolution CT scans, may enable earlier detection and timely initiation of antifibrotic treatment to improve outcomes.",
  "authors": [
    {
      "affiliations": [
        "Nottingham University Hospitals, Nottingham, UK"
      ],
      "name": "PA Hatton"
    },
    {
      "affiliations": [
        "Nottingham University Hospitals, Nottingham, UK"
      ],
      "name": "ML Battenfield"
    },
    {
      "affiliations": [
        "Nottingham University Hospitals, Nottingham, UK"
      ],
      "name": "MD Avoseh"
    }
  ],
  "title": "S153 ILA phenotype and progression in ILD patients in a tertiary ILD centre",
  "uid": "efddc362-64cd-5c04-b393-ceeb3148bfbc"
}