SAT0290 TRADITIONAL AND DISEASE-RELATED RISK FACTORS FOR ARTERIAL AND VENOUS THROMBOTIC EVENTS (TE) IN IDIOPATHIC INFLAMMATORY MYOPATHIES (IIM)
Authors: Antonella Notarnicola, Simone Barsotti, Linnea Näsman, Quan Tang, Marie Holmqvist, Ingrid E. Lundberg, Aleksandra Antovic
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> Thromboembolic cardiovascular diseases (CVD), affecting both arterial and venous sides, are one of the leading causes of death in patients with Idiopathic Inflammatory Myopathies (IIM), with highest peak of mortality within the first year after diagnosis (1). <h3>Objectives:</h3> To assess the prevalence of traditional and disease-related risk factors for arterial and venous thrombotic events (TE) in patients with IIM by comparing those reporting TE (cases) with those without history of TE (comparators). To compare clinical characteristics, autoantibody profile inclusive antiphospholipid antibodies (aPL) and serum levels of adhesion molecules (VCAM, ICAM and e-selectin) between cases and comparators as well as between cases reporting arterial vs venous TE. <h3>Methods:</h3> Using national and international registries, and medical charts, we identified 58 cases and 195 comparators with IIM followed at Karolinska University Hospital between 1993 and 2014. Information on gender, age at the time of diagnosis, IIM subgroup, presence of interstitial lung disease (ILD), myositis specific antibodies (MSAs), was retrospectively collected. Information on traditional risk factors for arterial and venous TE (essential hypertension, diabetes, dyslipidemia, smoking, malignancy) was retrieved for both groups. Serum levels of aPL and adhesion molecules were analyzed in stored sera from the time of diagnosis in both groups, before TE in cases and in 40 age and gender matched heathy controls (HC). <h3>Results:</h3> One out of 5 IIM patients (22,92%) had suffered from at least one TE, which was observed especially during the first 5 years after diagnosis. Myocardial infarction was the most frequent TE, followed by pulmonary embolism and deep venous thrombosis. In the multivariate analysis, male gender and older age were independent risk factors for TE. Essential hypertension had statistically significant higher prevalence in cases than comparators. Arterial TE was more common in polymyositis, while venous TE occurred more frequently in patients with dermatomyositis, history of malignancy and in those with MSAs. At time of IIM diagnosis, the prevalence of aPL was 6% with no difference between cases and comparators. Significantly higher levels of VCAM and ICAM were obtained in IIM patients compared to HC (Fig.1 and Fig.2). ICAM levels were found significantly higher in comparators than cases (Fig.2). Lower levels of e-selectin were associated with higher odds of developing TE, especially in males and older patients, with no difference between arterial and venous TE (Fig.3). <h3>Conclusion:</h3> A high risk of arterial and venous TE should be taken into account in patients with IIM, particularly close to time of diagnosis, with extra attention in male patients and older individuals. Preventive measures should be considered especially in patients with concomitant essential hypertension and malignancy. Lower serum levels of e-selectin might predict TE in IIM patients but the mechanism for this risk factor is not known. <h3>Reference</h3> [1] Dobloug GC, Svensson J, Lundberg IE, Holmqvist M. Mortality in idiopathic inflammatory myopathy: results from a Swedish nationwide population-based cohort study. Ann Rheum Dis. 2018;77(1):40-7. <h3>Disclosure of Interests:</h3> Antonella Notarnicola: None declared, Simone Barsotti: None declared, Linnea Näsman: None declared, Quan Tang: None declared, Marie Holmqvist: None declared, Ingrid E. Lundberg Grant/research support from: Dr. Lundberg has received honoraria from Bristol Myers Squibb and MedImmune and is currently receiving a research grant from Bristol Myers Squibb and from Astra Zeneca., Consultant for: She is a scientific advisor for Bristol Myers Squibb, and aTyr, Aleksandra Antovic: None declared