Interstitial lung disease (ILD) and signs of autoimmunity are present in patients with interstitial pneumonia with autoimmune features (IPAF), but they do not meet the criteria for connective tissue diseases (CTDs). In order to assess the prognosis of patients with IPAF, researchers set out to identify patients from an existing pulmonary cohort who might be classified as having IPAF, CTD-ILD, or idiopathic pulmonary fibrosis (IPF).

They examined the medical files of 456 patients from a cohort of patients with pulmonary ILD at a single hospital whose diagnosis had previously been made by a multidisciplinary team without rheumatologists. Patients were categorized as IPAF, CTD-ILD, or IPF. Using Kaplan-Meier techniques, they compared transplant-free survival and used Cox models to determine prognostic markers.

They found 126 patients with IPF, 113 patients with CTD-ILD, and 60 patients with IPAF. IPAF’s transplant-free survival was statistically comparable to those of CTD-ILD or IPF. Male sex among IPAF patients was independently linked to poorer transplant-free survival (hazard ratio, 4.58 [1.77-11.87]). Only 10% of IPAF patients received a diagnosis of CTD-ILD, most frequently antisynthetase syndrome, during follow-up.

Although most IPAF patients did not proceed to CTD-ILD despite sharing comparable clinical traits, those who did frequently acquired antisynthetase syndrome, emphasizing the vital significance of thorough myositis autoantibody testing in the cohort. Similar to other ILDs, IPAF may have a poorer prognosis if the patient is male. It will be easier to classify these patients correctly and to understand prognostic variables if rheumatologists are routinely included in the multidisciplinary examination of ILD.