Global Burden of Asthma and Atopic Dermatitis in 2021: A Systemic Analysis of the Global Burden of Disease Study 2021

We recently read the article by Shin YH et al., utilizing the Global Burden of Disease Study (GBD) 2019 to analyze the trends in the global burden of asthma and atopic dermatitis (AD) from 1990 to 2021 [1]. This study found that while the total number of cases has been increasing, the age-standardized prevalence rates have been declining. Given that the GBD has been updated to the 2021 version [2], it is essential to uncover the latest burden of asthma and AD. Therefore, we analyzed the prevalence, incidence, mortality, and disability-adjusted life years (DALYs) for asthma and AD, focusing exclusively on the data from 2021. Specifically, we conducted a cross-sectional analysis of the age-, sex-, and socio-demographic index (SDI)-specific burden, which is crucial for understanding the burden and informing strategies for prevention, control, and treatment. It is important to note that the GBD does not provide mortality data for AD. Consequently, our analysis and the presented figures do not include mortality data for this condition. In 2021, the highest age-standardized prevalence (ASP) and age-standardized incidence rate (ASIR) for asthma were observed in the High-income North America region, whereas the highest age-standardized mortality rate (ASMR) and age-standardized disability-adjusted life years (DALY) rate (ASDR) were reported in the Oceania region. For AD, the highest ASP, ASIR, and ASDR were all recorded in the High-income Asia Pacific region (Figure 1; Figure S1). In terms of age distribution, the ASP and ASIR of asthma are primarily concentrated in children and adolescents, whereas the ASMR and ASDR are predominantly observed in the elderly population. In contrast, the disease burden of AD is mainly concentrated in children and adolescents (Figure 2). Regarding gender differences, no significant disparities are observed in the burden of asthma between males and females. However, the burden of AD is notably higher in females compared with males, which may be attributed to multifaceted etiology, encompassing culturally idealized expectations of appearance for females, hormonal influences such as the impact of sex hormones on immune responses and skin barrier function and genetic predispositions with a spotlight on filaggrin gene mutations (Figure 2) [3-5]. When stratified by SDI, the ASP and ASIR of asthma are significantly higher in high-SDI regions than in low-SDI regions, whereas the ASMR and ASDR of asthma are markedly higher in low-SDI regions than in high-SDI regions, which is due to limited access to and affordability of essential asthma treatment medications, leading to severe morbidity [6]. On the contrary, the disease burden of AD is predominantly concentrated in high-SDI regions (Figure S2). Overall, our study underscores the heterogeneity in the burden of asthma and AD across different age groups, genders, and socio-demographic regions. Addressing these disparities requires targeted strategies that consider the specific drivers of burden in each context. For asthma, this should include improving access to preventive care and treatment in lower-income regions, while for AD, interventions aimed at early childhood may be most effective. Additionally, to effectively manage AD, key interventions include regular moisturization to maintain skin hydration and the use of emollients to repair the skin barrier. It is also crucial to avoid irritants and allergens, modify bathing practices by using lukewarm water and gentle, fragrance-free cleansers, and consider environmental controls such as maintaining optimal indoor humidity levels to prevent skin dryness and irritation. Our findings highlight the importance of context-specific interventions and underscore the need for continued monitoring and research to effectively reduce the burden of these common allergic diseases. We appreciate the excellent works by the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 collaborators. The authors have nothing to report. The authors have nothing to report. The authors declare no conflicts of interest. Data sources and code used in the Global Burden of Disease Study 2021 are available on the internet (http://ghdx.healthdata.org/gbd-results-tool). The data presented is unpublished elsewhere and are not duplicated. Figure S1. Age-standardized rates of prevalence, incidence, mortality and DALYs of asthma and atopic dermatitis in 2021 in 21 GBD regions. Error bars indicate the 95% uncertainty interval for age-standardized rates. Abbreviations: Age-standardized prevalence (ASP); Age-standardized incidence rate (ASIR); Age-standardized mortality rate (ASMR); Age-standardized disability-adjusted life years (DALY) rate (ASDR). Figure S2. Age-standardized rates of prevalence, incidence, mortality and DALYs of asthma and atopic dermatitis in 2021 in five SDI regions. Error bars indicate the 95% uncertainty interval for age-standardized rates. Abbreviations: Age-standardized prevalence (ASP); Age-standardized incidence rate (ASIR); Age-standardized mortality rate (ASMR); Age-standardized disability-adjusted life years (DALY) rate (ASDR). Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.