The changes in global burden of autoimmune diseases two years after the COVID-19 pandemic: a trend analysis based on the Global Burden of Disease Study 2021

Data on the epidemiological changes in the global burden of autoimmune diseases (ADs) after the Coronavirus disease 2019 (COVID-19) pandemic is lacking. This study investigated the impact of the COVID-19 pandemic on the global burden of ADs, including psoriasis (PsO), inflammatory bowel disease (IBD), type 1 diabetes (T1DM), rheumatoid arthritis (RA), and multiple sclerosis (MS). Age-standardized rates (ASR), including incidence (ASIR), prevalence (ASPR), disability-adjusted life years (DALYs), and death (ASDR), were extracted from the Global Burden of Disease Study 2021 from 1990 to 2021. The changes in number and ASR of ADs burden were assessed by absolute and relative increases comparing 2021 to 2019. Joinpoint regression analysis was used to determine whether the year 2019 marked the substantial changes in trends of ASR across global, 21 geographical regions, and 204 countries. The correlations between COVID-19 incidence, vaccination and the relative increased ASIR/ASPR of ADs were also evaluated. Joinpoint regression analysis identified 2019 as a pivotal year, marking a global increase in the burden of PsO. The global ASR of PsO in 2021 showed an increased incidence, prevalence, and DALYs of 0.78, 5, and 0.33 DALYs per 100,000, respectively, compared to 2019 (194.1 × 103 cases, 1651.3 × 103 cases, and 131.4 × 103 DALYs, respectively). Notable absolute increases in PsO incidence rates in 2021 were observed in regions with a high socio-demographic index, particularly among individuals aged 50 to 54 and among males. Furthermore, 2019 marked a joinpoint with increased ASIR or ASPR of ADs in various regions, notably PsO in High-income North America, Southern Latin America, and South Asia, as well as IBD in Southern and Eastern Sub-Saharan Africa, Central Europe, and East Asia. Regional data from the USA, England, and Japan indicated a positive correlation between COVID-19 incidence and relative increases in the burden of PsO in 2020 (Spearman R 0.35, 0.24, and 0.36, respectively, for incidence; R 0.35, 0.2, and 0.36, respectively, for prevalence; all p < 0.05). Additionally, 2021 state-level vaccination rates in the USA were negatively correlated with the relative increases in the ASIR of PsO and RA (R: 0.27 and -0.54, respectively; p < 0.001 for all), as well as the ASPR of PsO, RA, and MS (R: 0.45, -0.49, and -0.41, respectively; p < 0.01 for all) in 2021. The year 2019 marked a pivotal point for increased global burden of PsO and regional burdens of other ADs. These observations have important implications for subsequent healthcare planning and resource allocation.