Global, regional, and national trends in incidence of asthma: Findings from the global burden of disease study 2019

Introduction: We aimed to determine the geographical variation of asthma incidence over the past three decades to facilitate the initiation of more targeted strategies for asthma prevention. Methods: Detailed information on asthma during the last 30 years from a total of 204 countries and territories was collected from the Global Burden of Disease Study 2019. Age-standardized incidence rate (ASR) and number of incident cases were calculated to reflect the global pattern of asthma incidence. Temporal trends were quantified by average annual percent change (AAPC) using a join-point regression model. Results: The overall ASR has decreased from 1990 to 2019, with an AAPC of -0.41 (95%CI: -0.59 to -0.23). While new asthma cases increased in most parts of the world, with the most pronounced increase in Western Sub-Saharan Africa (AAPC = 2.51, 95%CI: 2.38 to 2.64), followed by Central Sub-Saharan Africa. The absolute number of new asthma cases also significantly increased worldwide (AAPC: 0.53, 95%CI 0.37,0.70) and most new asthma cases were reported in India. When classifying the geographical regions by socio-demographic index (SDI), more new cases were found in the low SDI region (AAPC = 2.24, 95%CI: 2.08 to 2.40). The most remarkable increase was observed in Qatar (AAPC = 5.68, 95%CI: 5.38 to 5.97), while the greatest decrease was in Japan (AAPC = -2.50, 95%CI: -2.67 to -2.32). Conclusions: Despite a decreasing trend of ASR on a global scale, we observed a remarkable increase in new asthma cases in countries and regions with low SDI. Our findings emphazise the need for geographically specific allocation of healthcare resources to forestall the increasing burden of asthma.