Objective The study aims to preliminarily investigate the prevalence characteristics of allergen-specific immunoglobulin E (IgE) in 57558 patients over the past decade by examining its distribution in the province and exploring its associations with age, sex, temperature, and relative humidity, providing insights for the prevention and diagnosis of allergic diseases in the Sichuan region.

Methods A retrospective analysis was conducted on a cohort of 57558 patients who underwent allergen testing (by means of EUROIMMUN immunoblotting method) at West China Hospital, Sichuan University between August 2012 and February 2022. The clinical data of these patients were collected to establish a comprehensive database, while the temperature and humidity records of the corresponding timeframe were gathered for further analysis. The positive results from the allergen tests were categorized into four levels, including weakly positive (±), positive (+), moderately positive (++), and strongly positive (+++). Statistical analyses were performed using SPSS 25.0, with Chi-square tests conducted to compare count data and Pearson's correlation tests done conducted to assess the relationships between different types of allergens and temperature/relative humidity. P<0.05 was applied to determine statistically significant differences. GraphPad Prism 9.0.0 was utilized to generate visual representations of the data.

Results The overall positivity rate of allergen-specific IgE among the 57558 samples was 30.69%. The top five allergens that elicited positive results were dust mite mix 1 (14.46%), crab (6.67%), soybean (4.72%), fish mix 1 (4.64%), and cockroach (4.34%). Notably, weakly positive (±) results were predominant for allergens such as eggs, peanuts, soybeans, cow's milk, beef, mutton, crab, shrimp, fish mix 1, cockroach, humulus japonicus, ambrosia artemisifolia, artemisia vulgaris, tree mix 2, house dust, and mold mix 1, collectively constituting over 40% of the positive outcomes. In contrast, cat hair and dog dander exhibited an equal distribution of approximately 25% for each positive levels, while mite mix 1 demonstrated the highest proportion of strongly positive results (+++), accounting for 37.66% of all positive results. Sex disparities in positivity rates were evident for various allergens, with significant differences observed for peanut, soybean, crab, shrimp, fish mix 1, cockroach, ambrosia artemisifolia, tree mix 2, cat hair, dog dander, and mite mix 1. Furthermore, the study identified age-related trends in allergen positivity rates, with a general decline observed across most allergens with increasing age. The positive rate of at least one food allergen was highest in the 0-10 age group (36.18%), and the positive rate of at least one inhalation allergen was highest in the 11-20 age group (45.35%). Noteworthy correlations were observed between allergen-specific IgE positivity and environmental factors, including a strong negative correlation between cow's milk allergy and relative humidity (r=−0.640, P<0.05), a strong negative correlation of artemisia vulgaris sensitivity with temperature (r_{Mean high temperature}=−0.695, r_{Mean low temperature}=−0.692, P<0.05), and a very strong positive correlation of mold mix 1 sensitivity with relative humidity (r=0.704, P<0.05).

Conclusion Allergen-specific IgE positivity is associated with genetic factors, demonstrates significant sex- and age-related characteristics in the population, and is influenced by changes in local temperature and relative humidity.