Introduction. We consider it relevant to study the modern epidemiology of MS in Novosibirsk over the past 20 years. The purpose of the study: to study the dynamics of the prevalence and incidence of MS from 01.01.2003 to 01.01.2024 in Novosibirsk in comparison with the previous 20-year study. Materials and methods: The prevalence cohort included 2,254 MS patients living in Novosibirsk on 01.01.2024.. The incidence cohort consisted of 1998 patients with the onset of the disease from 01.01.2003 to 31.12.2023 inclusive. The influence of the heterogeneous sex and age composition of the population was offset by the method of standardization of indicators (standard European population, 07/13/2013). The results of the study. The prevalence of MS as of 01.01.2024 was 137.83 per 100,000 population (the standardized indicator was 123.43). The average age of the observed MS patients was 46.146±0.479 years. The incidence of MS from 2003 to 2023 shows an increasing trend – from 5.12±0.0662 to 7.71±0.0246 per 100,000 population/year (p<0.05), which is mainly due to a significant increase in the proportion of women (from 6.56±0.1118 to 11.01±0.091 per 100,000 population/year, p<0.05), but not men (p>0.05). The average age of onset of MS increased by 0.146 years annually during the study period and amounted to 30.479±0.329 years (rxy=0.08, p<0.001). An increase in the incidence of early and late MS was noted (rxy=0.45, p=0.041 and rxy=0.622, p=0.003, respectively). Conclusions. In the era of a controlled course of the disease, our study showed an increase in the prevalence of MS over 20 years (from 54.4 to 137.83 per 100,000 population). There was an increase in the incidence of MS (p<0.05), mainly due to women (p<0.05). The age of MS onset increased significantly over the 20-year follow-up period (p<0.05). An increase in the incidence of early and late MS (p<0.05) has been shown.

Ivan Arkhipov graduated from the Federal State Budgetary Educational Institution of Higher Education Novosibirsk State Medical University of the Ministry of Health of the Russian Federation in 2019 with a degree in general medicine, in 2021 with a degree in neurology, in 2024 with a postgraduate degree in Clinical Medicine and wrote his dissertation on the topic "Dynamics of epidemiological and clinical characteristics of multiple sclerosis in the south of western Siberia (on the example of the city of Novosibirsk)".