A comparative study to evaluate factors affecting adverse outcomes in interstitial lung diseases with Idiopathic pulmonary fibrosis (IPF) and other non-IPF interstitial lung diseases at 6 months in a tertiary care centre

Abstract

Introduction and aim of the study: The diagnosis and treatment of interstitial lung diseases (ILD), a class
of diffuse parenchymal lung disorders that are associated with significant morbidity and death, provide
challenges to the clinician. Multidisciplinary discussions (MDD) between a clinician, radiologist, and
pathologist are used to diagnose ILD. There is a lack of information on the use of composite prediction
models such as the ILD Gap Index and the Composite Physiologic Index. The main objective of the study
was to evaluate factors affecting adverse outcomes in interstitial lung diseases with idiopathic pulmonary
fibrosis (IPF) and other non-IPF interstitial lung diseases at 6 months in a tertiary care centre.

Material and methods: This was a retrospective cohort research carried out at a tertiary care centre at Howrah,
a district of state West Bengal in India. The main inclusion criteria were to include all patients who had complete
medical records after being diagnosed with ILD. Any patients who suffered from pulmonary TB or lung
cancer were excluded. The study comprised 164 consecutive individuals with a multidisciplinary diagnosis
of interstitial lung disease. At 6 months, clinical evaluation, spirometry and DLCO were performed on the
patients. FVC reduction of less than 10% at 6 months and mortality were evaluated as outcome variables.

Results: Idiopathic pulmonary fibrosis (IPF) affected 27.2% of the 164 patients who were evaluated, while
non-IPF affected 72.8% of the patients. At a 6-month follow-up, 15.2% of patients died, with 72% having IPF.
At 6 months, the FVC of 51.2% had decreased by 10%. Age more than 60, male gender, BMI 18,5, smoking,
the presence of pulmonary hypertension, mean saturation more than 90%, percentage predicted FVC more
than 50%, percentage predicted DLCO more than 40 per cent, 6-minute walk distance more than 250 m at
diagnosis, UIP pattern in HRCT, CPI score more than 50, and ILD-GAP index more than 4 are factors associated
with mortality in interstitial lung diseases. Age more than 60 years old and IPF group were variables
linked with death in multivariate analysis using logistic regression in bivariate analysis, the same factors
were linked to a reduction in FVC of more than 10% at 6 months, whereas in multivariate analysis, smoking
history and an initial projected DLCO of less than 40% were significant. In interstitial lung disorders, the ILD
Gap index is a better predictor of death than a composite physiologic index. (AURO 0.912 vs., CPI 0.856).

Conclusions: Interstitial lung disease mortality indicators include age more than 60, idiopathic pulmonary
fibrosis type, and FVC decline ≥ 10% at 6 months and less than 50% at baseline. Prediction methods like
composite physiologic index (CPI) and ILD Gap index aid prognosis and clinical decision-making. The
ILD Gap index predicted mortality better than the composite physiologic index. The main objective of
the study was to evaluate factors affecting adverse outcomes in interstitial lung diseases with idiopathic
pulmonary fibrosis (IPF) and other non-IPF interstitial lung diseases at 6 months in a tertiary care centre.