Purpose
To identify early predictive markers in patients with chronic interstitial pneumonia (IP) associated with an underlying autoimmune disease (AIP), aiming to facilitate personalized follow-up and treatment.
Methods
We assessed the predictive value of process and host factors on mortality in a cohort of 124 patients (86 women) with autoimmune interstitial pneumonia (AIP). This cohort comprised 66 cases of connective tissue disease-associated interstitial pneumonia (CTD-IP), 40 patients with interstitial pneumonia with autoimmune features (IPAF), and 18 patients with undifferentiated autoimmune IP. All patients had a minimum follow-up of 2 years or a fatal outcome. We included demographics, clinical diagnostic subgroups, specific antibodies, morphological patterns, and relevant laboratory tests in our analysis. For the bivariate analysis, we employed Student's t-test, Fisher's exact test, and survival techniques. Prediction models for death risk were developed using logistic regression.
Results
During the follow-up period, there were 29 deaths, resulting in an incidence rate of 3.09 per 100 patient-year. Factors associated with an increased risk of death included older age at diagnosis, cardio-respiratory comorbidities, and a simultaneous onset of intersticial pneumonia and systemic manifestations. In contrast, clinical diagnosis and radiographic patterns did not show a significant association with mortality risk. Additionally, elevated levels of lactate dehydrogenase, sedimentation rate, C-reactive protein, and ferritin were significantly linked to fatal outcomes. Among these, ferritin emerged as the most potent predictor in the multivariate model, with an odds ratio of 5.9 (p=0.002).
Conclusion
Our data emphasize the importance of monitoring inflammatory markers, particularly ferritin levels, to assess prognosis across various subtypes of autoimmune intersticial pneumonia.
