Identification of factors associated with acute respiratory failure in patients with interstitial lung disease

Aims: In this study was aimed to identify epidemiological data on the causes of acute respiratory failure (ARF) in patients with interstitial lung disease (ILD). Materials and Methods: This prospective study was carried out between 01.12.2020 - 31.12.2021 at Karadeniz Technical University Department of Chest Diseases. Patients with a diagnosis/prediagnosis of ILD who had PaO2/FiO2≤300 mmHg despite oxygen supplementation at a flow rate of ≥10 L/min for at least 15 minutes or increased respiratory effort and patients with a diagnosis/prediagnosis of ILD hospitalized for reasons other than respiratory failure were included in the study. The clinical and demographic characteristics, comorbidities, laboratory and radiological data of the patients were recorded, and the evaluation was made by grouping them according to the reasons for hospitalization. Results: Of the 109 patients in the study, 45% were female and 55% were male, with a mean age of 65.80 ± 10.52 years. A total of 45 patients were admitted to acute respiratory failure. It was determined that respiratory failure developed due to pulmonary infection in 48,9%, primary disease exacerbation in 24,4%, PTE in 13,3%, and congestive heart failure in 8,9% of patients. The presence of idiopathic pulmonary fibrosis in 37,8%, collagen tissue disease- ILD in %22,2, hypersensitivity pneumonia in 15,5% and drug-related ILD were found in 13,3% of the patients presenting with acute respiratory failure. The patients were hospitalized for fibrotic progression (9,2%) and ILD investigation (53,2%) . It was found that the parameter levels related to pulmonary function assessment did not differ according to ARF, ILD research and fibrotic progression groups (p>0,05). Age, gender, smoking history, accompanying comorbidity and accompanying chronic lung disease did not differ between the primary disease exacerbation, fibrotic progression and ILD research groups (p>0,05). Although the presence of primary disease exacerbation was not statistically significant, it was found to differ between the groups according to the normal weight, overweight and obese status of the patients; normal weight primary disease exacerbation was detected in 12% of patients, 14% of overweight patients, and 4.9% of obese patients.While leukocyte, eosinophil and total IgE values did not differ according to the reasons for hospitalization (p>0,05); d-dimer, monocytes and CRP values were found to differ according to the reasons for hospitalization (p≤0,05). The lowest d-dimer and monocyte values were found in the fibrotic progression group, while the lowest CRP values were found in the ILD research group. Primary disease exacerbation is higher in those who have annual influenza vaccination (22,7%) than those who do not (6,9%). Conclusion: In this study were created the detailed epidemiological data on the causes of ARF in patients with ILD. It is thought that the data obtained will contribute to the definition of ARF in patients with ILD.