Background Interstitial lung disease (ILD) in idiopathic inflammatory myopathies (IIM) may appear at any time in evolution and is associated with a worse prognosis.

Objectives To investigate sociodemographics data and clinical characteristics of patients with IIM and ILD from the REMICAM registry.

Methods A multicenter retrospective study (1980–2014) was performed. Patients were classified as polymiosytis (PM), dermatomyositis (DM), IIM with anti-synthetase antibodies (AB) and overlap syndrome. In addition, ILD was classified according to HRCT pattern: usual interstitial pneumonia (IP), non specific IP, organizing pneumonia, and acute IP. We compared sociodemographic data, clinical characteristics, AB and treatments of patients with and without ILD, patients with ILD according to subgroup of myositis or ILD.

Results 478 patients were included, of whom 129 (27%) had ILD. Patients with ILD had a higher age at diagnosis, ESR and CRP and worse initial respiratory function. They were characterized by increased frequency of arthritis, systemic and cardiac manifestations, Raynaud, cardiovascular disease, pulmonary hypertension, ischemic ulcers, sclerodactyly and anti-synthetase AB (p<0.001). The differences among patients with ILD were: less arthritis in PM, greater frequency of Raynaud and sclerodactyly in overlap and antisynthetase syndrome, more anti-RNP AB in the overlap syndrome, more anti-synthetase and anti-Ro AB in the antisynthetase syndrome, and a higher prevalence of cutaneous signs and mechanical hands in DM (p<0.001). There were no differences according to the type of ILD or treatments.

Conclusions We found some clinical manifestations and AB that may help for detection of patients with IIM associated to ILD, as well as clinical manifestations to better differentiate myositis subtypes in patients with ILD.

Disclosure of Interest None declared