Full Papers
Seasonal prevalence of myositis-associated and myositis-specific autoantibodies in a Greek patient cohort over a period of 8 years.
L. Papa1, S. Raftopoulou2, C. Skarlis3, C.P. Mavragani4
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, Greece.
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, Greece.
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, Greece.
- Department of Physiology, Medical School, National and Kapodistrian University of Athens; Department of Pathophysiology, Medical School, National and Kapodistrian University of Athens; and Joint Academic Rheumatology program, Medical School, National and Kapodistrian University of Athens, Greece. kmauragan@med.uoa.gr
CER19
Full Papers
Received: 23/08/2025
Accepted : 24/09/2025
In Press: 01/10/2025
Abstract
OBJECTIVES:
Idiopathic inflammatory myopathies (IIMs) are a group of rare systemic autoimmune diseases primarily characterised by immune-mediated myocyte destruction and skeletal muscle inflammation. The recent introduction of myositis-associated and -specific autoantibodies (MAAs/MSAs) in clinical practice has revolutionised the early diagnosis and stratification of patients with IIMs. Environmental factors such as seasonal changes can influence the occurrence of specific autoantibodies or the onset of ΙΙΜs. Here, we aimed to investigate the seasonal prevalence of MAAs and MSAs in a Greek patient cohort.
METHODS:
Serological data were collected from 1896 patients referred for MAA/MSA detection between February 2017 and January 2025 via line immunoassays. Seasonality was evaluated by performing the Rayleigh test (for circular data) and the Chi-squared test (for ratios of positive tests).
RESULTS:
Of 1896 LIAs performed for the detection of MAAs and MSAs, 888 were positive for at least one autoantibody. The prevalence of positive MAAs was significantly higher compared to MSAs (χ² test, p<0.001). Among MAAs, anti-PM-Scl100 and anti-PM-Scl75 autoantibodies were significantly more frequent in the fall-winter seasons (χ² test; p=0.008 and p=0.026, respectively). Among MSAs, no significant seasonal associations were observed. Finally, the analysis of autoantibodies positivity rates between springsummer and fall-winter seasons before COVID-19 (2017-2019) and during COVID-19 (2020-2024) did not show statistically significant differences.
CONCLUSIONS:
The findings on seasonal prevalence of anti-PM-Scl100 and anti-PM-Scl75 autoantibodies suggest that various environmental factors present in different seasons of the year may trigger distinct immune responses and clinical manifestations in IIM.
