Registries in idiopathic inflammatory myopathies

Purpose of reviewThe idiopathic inflammatory myopathies myositis are rare diseases with limited information on risk factors for disease and prognosis. The aim of this review is to give an overview of how registries can be used in myositis research.Recent findingsPopulation-based registries have been used in a number of incidence and prevalence studies in the review period and have shown myositis to be more common than previously reported. Disease-specific registries have been used for detailed studies on subphenotypes and longitudinal studies to identify prognostic markers and treatment outcomes.SummaryRegistries, both national healthcare and health insurance registries, as well as disease-specific clinical registries, are useful sources to investigate a rare disease like myositis. To achieve increased understanding of whether different subphenotypes differ in treatment outcome and prognosis, a large number of patients need to be followed longitudinally in a systematic way. A novel international, multidisciplinary registry, EUROMYOSITIS, has been developed. This is an open source registry with to date 20 centers and more than 2500 patients with myositis, many of whom are followed longitudinally. This registry has clear potentials for clinical and epidemiological research, as well as for clinical trial in myositis, and welcomes investigators from all over the world.