100086 - High Prevalence of Atopy in a General Population

Epidemiological studies in the general population are useful to know the prevalence of diseases, respiratory allergic diseases among them.

The aim of the present study was to assess the prevalence of atopy a general population, and to investigate the relationship between sensitization to inhalants with demographic factors, and the presence of symptoms of rhinoconjunctivitis and/or bronchial asthma.

We conducted a cross-sectional study developed in A-Estrada (Galicia, Spain), The A-Estrada Glycation and Inflammation Study (AEGIS) (available at www.clinicaltrials.gov, code NCT01796184).

A random sample was obtained and stratified by 7 age groups (n=500 in each group): 18 to 29 years; 30 to 39 years; 40 to 49 years; 50 to 59 years; 60 to 69 years; 70 to 79 years; and 80 years and older. The participation rate was 68% (1516 subjects who agreed to participate in the study; 44.7% male; median age 52 years, range 18-91 years).

Variables studies were: total serum IgE, total alcohol intake, level of education, type of exposure, housing conditions, level of physical exercise, skin prick test to common inhalants, rhinitis and asthma questionnaires.

The mean overall prevalence of, at least, one positive SPT was 21.9% for the whole population. The prevalence of atopy was as high as 43.2% in the youngest group of people (18-29 years-old) and it decreased with age.

House dust mites (HDM) were the most frequently positive allergen. Participants sensitized to HDM, were younger and with a higher percentage of men. Sensitization to Lepidoglyphus destructor was much more frequent among the personnel we have considered as occupationally at risk and which includes exposure in storage areas, contact with grain and farm animals, as well as storage of all kinds. When comparing subjects with a positive SPT to HDM with atopic subjects who had a negative SPT result, the proportion of patients suffering from respiratory symptoms was higher in the first group compared to the second (55.8% vs. 41.7%, p=0.046). The number of positive SPTs appears to be related to respiratory symptoms. The higher the number of positive SPTs, the more respiratory symptoms were reported (p<0.001).

HDM sensitization is highly prevalent in the general population studied and it is related to respiratory symptoms. Moreover, the number of sensitizations correlates with the prevalence of symptoms.