Multiinstitutional prospective study on idiopathic interstitial pneumonias with features similar to collagen vascular diseases - IIPs with features similar to CVD

In this multicenter cohort study, 376 patients with IIP prospectively enrolled, and 70 patients (18.6%) met the IPAF criteria. During a median observation period of 35 months, patients with IPAF more frequently developed systemic autoimmune diseases and had less frequent acute exacerbation of IIPs than patients with non-IPAF. IPAF diagnosis was significantly associated with better survival and was an independent positive prognostic factor in total and patients with non-IPF.