Yoshimura K, et al. - Patients with chronic fibrosing interstitial pneumonia (CFIP) often have clinical, serologic, and morphologic features suggestive but not diagnostic of connective tissue disease. Herein, the clinical features, as well as prognostic significance of interstitial pneumonia with autoimmune features (IPAF), was elucidated. In patients with CFIP, a favorable prognosis and less risk of acute exacerbations might be predicted by a diagnosis of IPAF. Data showed that patients with IPAF vs those without IPAF were significantly younger and included a higher proportion of women, never-smokers, and patients with nonspecific interstitial pneumonia.

• Researchers retrospectively explored the clinical characteristics and prognostic relevance of a diagnosis of IPAF in 194 patients with CFIP, including 163 with idiopathic pulmonary fibrosis (IPF) and 31 with nonspecific interstitial pneumonia (NSIP), in their interstitial lung disease database.

• The criteria for IPAF was met by 16 % of patients with CFIP (8% of IPF, 61% of NSIP).
• Data showed that patients with IPAF vs those without IPAF were significantly younger and included a higher proportion of women, never-smokers, and patients with NSIP.
• In patients with IPAF (97%), the most common was the morphologic domain, followed by the serologic domain (72%) and clinical domain (53%).
• Compared with those without IPAF, CFIP patients with IPAF had a more favorable prognosis with regard to overall survival (OS; P < 0.001, log-rank test) and incidence of AEs (P=0.029, Gray's test).
• In the subgroup analysis, it was noted that NSIP patients with vs without IPAF had significantly better survival (P=0.031, log-rank test), and IPF patients with IPAF tended to have better OS than those without IPAF (P=0.092, log-rank test).
• However, in the IPF and NSIP subgroups, no significant differences were noted in the incidence of AEs between patients with IPAF and those without IPAF.
• Furthermore, researchers noted that fulfilment of the IPAF criteria was an independent predictor of OS (hazard ratio (HR) 0.127; 95% confidence interval (CI) 0.017–0.952; P=0.045) and incidence of AEs (HR 0.225: 95% CI 0.054–0.937; P=0.040).