Global, Regional, and National Temporal Trend and Patterns of Change in the Burden of Asthma From 1990 to 2021: An Analysis of the Global Burden of Disease Study 2021

Background

Asthma presents a significant challenge to the global healthcare systems and imposes a heavy socioeconomic burden. Previous studies had geographical limitations and lacked comprehensive global analysis. The study utilises data from the 2021 Global Burden of Disease (GBD) study to assess the global, regional, and national burden of asthma from 1990 to 2021. It examines disease trends, highlights health inequalities and aims to provide scientific evidence for future public health strategies and the optimisation of resource allocation.

Methods

Data from GBD 2021 were used to estimate the incidence, prevalence, mortality, and disability-adjusted life years (DALYs) of asthma across 21 global regions and 204 countries and territories from 1990 to 2021. Temporal trends were analysed, and the relationship between asthma burden and the socio-demographic index (SDI) was examined using a smoothing spline model. Analyses included the slope index of inequality and the concentration index to assess health disparities, frontier analysis to estimate achievable outcomes based on development levels, and decomposition analysis to identify the drivers of changes in DALYs number.

Results

Over the past three decades, the age-standardised burden of asthma has declined, with age-standardised mortality and DALY rates decreasing by 46% and 44%, respectively. However, the absolute number of deaths has increased by 17%, particularly among females, especially in low and low-middle SDI regions. Significant health inequalities persist, with high-SDI regions benefiting from better asthma control, while low-SDI regions face disproportionate burdens due to healthcare disparities. Frontier analysis highlights gaps between current and optimal disease burden levels, while low-SDI regions require increased investment in asthma control. Aging, population growth, and epidemiological changes are key drivers of asthma burden trends. High body mass index (BMI) remains the leading risk factor, while smoking and occupational exposures continue to contribute significantly.

Conclusions

The global burden of asthma has declined, yet significant regional disparities persist, with low-SDI regions experiencing higher mortality and DALYs due to limited healthcare access and environmental risks. High BMI, smoking and occupational exposures remain key contributors, requiring targeted public health interventions and lifestyle modifications.