Seasonal characteristics of debut of illness and complications in relapsing-remitting multiple sclerosis

Abstract

Relapsing-remitting multiple sclerosis (RRMS) is the most common demyelinating disease characterized by periods of disease exacerbation followed by partial or complete remission. Environmental risk factors in the occurrence of MS are widely studied. However, temporal, especially seasonal, fluctuations of multiple sclerosis (MS) and its relapses require clarification. The aim of the study was to assess the impact of seasonal factors on the debut of the disease and complications of RRMS. 105 patients diagnosed with RRMS, aged 18 to 49 years, were examined, including 74 women (70.5%) and 31 men (29.5%). Patients underwent comprehensive clinical-anamnestic and neurological examinations. It was found that the debut of the disease in the majority of examined patients occurred in the spring months, and there was also an associative connection between the month of diagnosis establishment and the number of exacerbations in the past year. The highest number of exacerbations throughout the year was observed among patients diagnosed with MS in the spring months. It was confirmed that the lowest frequency of exacerbations throughout the year was observed among patients receiving diseasemodifying therapy (DMT), while in patients without DMT, the indicator was the highest and exceeded (p<0.001) the indicator among patients receiving DMT by 72.5%. It was also established that the level of comorbid pathology in the group of patients not receiving DMT was higher compared to those examined who received therapy by 2.4 times (p<0.001). Correlation analysis showed that the number of comorbidities correlated with the season of the last exacerbation, the number of exacerbations in the past year (p<0.001), the number of symptoms of MS debut (p<0.001), and the use of DMT (p<0.001).