Asthma epidemiology: has the crisis passed?

Area of Science:

• Pulmonology
• Epidemiology
• Public Health

Background:

• Asthma is a significant global health concern, characterized by increasing prevalence over recent decades.
• This rising trend has led to substantial healthcare burdens, including symptoms, hospitalizations, and mortality.
• Emerging reports suggest a potential stabilization in asthma prevalence, prompting scientific debate.

Purpose of the Study:

• To review recent scientific literature addressing the ongoing debate on whether the increasing trend in asthma prevalence has ended.
• To synthesize findings on the current status of asthma prevalence and its associated burden.

Main Methods:

• Systematic review of recent literature on asthma prevalence.
• Analysis of cross-sectional studies, physician visits, hospitalization, and mortality data.
• Consideration of disease heterogeneity in prevalence estimation.

Main Results:

• Several recent studies indicate a stabilization of asthma prevalence, contrasting with earlier reports.
• However, findings from repeated cross-sectional studies are inconsistent, influenced by asthma's heterogeneity (diagnosis, symptoms, sensitization).
• Temporal trends in physician visits, hospitalizations, and mortality show more consistent patterns of stabilization and decrease.

Conclusions:

• The reasons for initial increases in asthma prevalence remain unclear, making explanations for stabilization elusive.
• Accurate asthma definition in population studies and methodological inconsistencies complicate prevalence estimation.
• Continued monitoring of asthma prevalence is recommended, with a focus on regions undergoing environmental and social changes.