Idiopathic inflammatory myositis is associated with a high incidence of hypertension and diabetes mellitus.

Aims: The long-terms complications of immunosuppressive and anti-inflammatory treatment in idiopathic inflammatory myositis (IIM) are unknown. We sought to determine the complications of these treatments in a large cohort of patients with biopsy-proven IIM.
Methods: A South Australian database for patients with biopsy-proven IIM was established. Clinical details of patients including treatment received were recorded.
Results: Forty-three patients with dermatomyositis (DM), 184 with polymyositis (PM) and 117 with inclusion body myositis (IBM) were registered on the database. The prevalence of hypertension and diabetes in this population was 62% and 29%, respectively, considerably higher than the background prevalence of 9.4% and 4%, making detection of treatment-related adverse effects difficult. Hypertension and ischemic heart disease were more likely to be present prior to the diagnosis of IIM rather than following it. Hypertension and diabetes occurred more frequently following the diagnosis of myositis, in patients with DM compared with PM or IBM.
Conclusions: We report a novel association of IIM with hypertension, diabetes and ischemic heart disease, indicating that a comprehensive assessment of vascular risk factors is essential in IIM.