Asthma is characterized by exacerbations, mainly caused by viruses or allergens. Epidemiologic evidence has shown that the combination of these risk factors is particularly harmful to asthmatics. The aim of this study was to assess asthmatic exacerbations (AE) risk factors due epidemics of two comparable asthma phenotypes, non atopics (NA) and house dust-mites (HDM) monosensitized asthmatics and investigate the interaction between viruses and allergens by the study groups’ ΑΕ comparison.
Methods:
We studied 342 monosensitized to HDM patients (214 males, 128 females) exhibiting 590 AE and 1518 NA (736 males, 782 females) exhibiting 2585 AE between 1992 and 2012. Epidemics regarding age, gender, annual waveform were analyzed using the null hypothesis. Seasonal variability of the two groups was compared by multiplying the quotient of patients’ numbers in the smaller sample by the corresponding number of the greater sample.
Results:
“Gender” is risk factor only in NA. Greater prevalence of AE in NA females was shown, but without statistical difference between males and females in HDM asthmatics. “Age” is risk factor in both groups. In HDM sensitized patients, AE are significantly more frequent before the age of 44, especially in “15-29 years old” subgroup in NA in “0-14 years old” one. Significant statistical difference appears in the AE number during the year in both groups, meaning seasonal variability. Seasonal peaks of the two groups differ till the age of 44, but correlate significantly afterwards.
Conclusions:
Knowledge on AE epidemics could contribute to their prevention since treatment should possibly be adjusted according to the seasonal peaks of them. The study’s results don’t support the theory of rhinoviruses and allergens interaction as risk factors of AE.