Background Idiopathic Inflammatory Myopathies (IIMs) are a group of rare systemic autoimmune diseases, characterized by chronic inflammation of the muscle, resulting symmetric proximal weakness, characteristic rashes and other systemic features. The etiopathology of the disease is poorly understood, but many evidences suggest that results from interaction of genetic risks and environmental exposures.
Objectives We wanted to obtain information about the environmental exposures of the Hungarian patients with IIMs. We aimed to find interactions between environmental factors and different myositis-specific and myositis-associated antibodies.
Methods Data were collected from Environmental Questionnaires (regarding smoking, alcohol consumption, infections, medication, vaccination, eye color, sunburn, etc.) completed by Hungarian patients with IIMs. Medical records were reviewed for the patients; phenotypes and autoantibody status were determined by standard clinical and laboratory measures. Statistical analysis was done using Pearson Chi-square and t-tests or Fisher’s exact test.
Results A total of 119 Hungarian adult onset IIM patients completed the Questionnaire. The proportion of females was 74%, as usually in IIMs. The median age at diagnosis was 42.86±13.25 years. Fifty-seven per cent (n=68) of the patients suffered from polymyositis (PM), 26% (n=31) had dermatomyositis (DM) and 17% (n=20) had myositis-connective tissue disease overlap. The frequency of anti-Jo-1 was 16% (n=19), whereas proportion of the anti-SSA, or anti-SSB antibodies was 27% (n=32). The frequency of smoking was significantly increased in the anti-Jo1 positive population (78% vs. 37%, OR: 1.32, 95% CI: 1.1-1.58, p=0.001). The alcohol consumption more the once per week was also significantly higher in the anti-Jo-1 positive population (63% vs. 37%, OR: 1.19, 95% CI: 0.998-1.423, p=0.034). Comparing the anti-SSA/SSB positive patients with the negative cases, we found, that the anti-SSA/SSB positive population is significantly younger at the set of diagnosis (38.81 ys vs. 44.35 ys, p=0.043), consists more women (96% vs. 65%, RR: 1.494, 95% CI: 1.264-1.766, p=0.001) and had more stressful life in the 12 months period before the diagnosis (96% vs. 80%, RR: 1.363, 95% CI: 1.148-1.618, p=0.04). We could not find any significant interactions regarding the proportion of infections, medications, vaccination, chemical exposures in the 12 months period before the patient’s diagnosis and the autoantibody status.
Conclusions It seems that smoking and alcohol consumption are associated with the increased possession of anti-Jo1 autoantibody in the Hungarian patients with myositis. Thus, these environmental factors might contribute to the development of anti-Jo-1. Significant alterations were found in the gender, age at diagnosis and stressful life of IIM patients regarding the anti-SSA/SSB positivity. Study of environmental factors and epigenetics in IIM patients might be useful to better understand disease pathophysiology.
Disclosure of Interest None Declared