The Impact of Climatic, Socioeconomic, and Geographic Factors on the Prevalence of Allergic Fungal Rhinosinusitis: A Worldwide Ecological Study.

Background: The prevalence of allergic fungal rhinosinusitis (AFRS) and its associated risk factors have been an issue of debate. Some epidemiological factors have been correlated to the disease prevalence.

Objectives: To observe the prevalence pattern of AFRS worldwide and to investigate the effect of specific epidemiological factors on the disease prevalence.

Methods: A systematic review was derived from 1983 to December 2018. Data on the prevalence of AFRS were collected from the selected studies. Relevant factors assessing each city's climate, socioeconomics and geography were used to study the association with AFRS prevalence.

Results: 35 cities across 5 continents were investigated. The worldwide average rate of AFRS in CRS cases is 7.8% (0.2%-26.7%) in which more than half of the investigated cities (57%) had low AFRS prevalence, while the remaining cities had intermediate (11%) and high (32%) prevalence. Cities with higher temperatures were associated with a higher prevalence of AFRS (-value 0.002), whereas cities with humid continental climate were significantly associated with a low prevalence of AFRS (-value 0.032). Humidity and wind speed were lower in the cities with higher AFRS prevalence (-value 0.018 and 0.008, respectively). There were no significant correlations between AFRS prevalence and economic levels, presence of water bodies, rainfall amounts, altitude, and presence of forests.

Conclusion: AFRS has a worldwide distribution pattern with varying prevalence. In this ecological study, we observed a correlation between AFRS prevalence and climatic factors (climate classification, humidity, temperature, and wind speed). Socioeconomic factors should be analyzed on an individual basis for better assessment of the relationship with disease prevalence.