Place of residence, gender, month of birth and age influence on the concentration of specific IgE antibodies in serum. The Epidemiology of Allergic Diseases in Poland (ECAP survey): part three

Introduction
Specific immunoglobulins E (sIgE) are important parameters to estimate the severity of allergic diseases.

Aim
To determine the influence of gender, age and place of residence on the concentration of specific IgE antibodies in serum.

Material and methods
The concentration of sIgE antibodies against allergens of Dermatophagoides pteronyssinus, cat dander, timothy grass, Alternaria alternata were determined in serum of 4077 respondents randomly selected from 8 regions (ECAP study). The positive results of sIgE (≥ 0.35 IU/ml) were correlated with answers to ECAP questionnaires.

Results
IgE antibodies are less frequently detected in respondents living in the country (p < 0.05 to p < 0.005); and they are less frequently detected in respondents living in cities of hardly industrialised regions than in respondents living in cities of industrialised regions (D. pteronyssinus p < 0.05, cat dander p < 0.01). IgE antibodies are more frequently detected in men (p < 0.005 to p < 0.001). IgE antibodies are more frequently detected in respondents born in May-July (timothy grass p < 0.005, Alternaria alternata p < 0.005) and less frequently detected in respondents born in August-October (timothy grass p < 0.005, Alternaria alternata p < 0.05).

Conclusions
Characteristics of the urban environment, non-specific factors and gender affect the concentration of specific IgE antibodies in serum. Influence of seasonal allergens within the first months of life and/or in the course of the foetal period alters the production of specific IgE antibodies.