How to put the burden from pollen allergy into numbers: Evaluation of ten years´ electronic generated symptom data from the PHD (Patient´s Hayfever Diary) in Austria and Germany (Preprint)

Abstract

BACKGROUND Pollen allergies concern a significant proportion of the population globally. Today, online tools such as pollen diaries and mobile applications allow an easy and fast documentation of allergic symptoms via the internet. OBJECTIVE This study aimed to characterize the users of the Patient´s Hayfever Diary, to apply different symptom score calculations for comparison and to evaluate the contribution of organs and medication to the total score for the first time. METHODS Users of the Patient´s Hayfever Diary were filtered concerning their location (Austria/Germany), significant positive correlation to the respective pollen type (birch/grass) and at least 15 entries in the respective season. Four different symptom score calculation methods were applied to the datasets from 2009 until 2018, among them two raw symptom scores and two symptom load indices (normalized) calculations. Pearson correlation coefficients were calculated pairwise for four symptom score calculations. RESULTS Users are mostly male and in the age group of 21 to 40 years or in the group above 40 years. User numbers increased in the last years, especially when mobile applications were made available. The Pearson correlation coefficients show a significant linear relationship above 0.9 between the four symptom score datasets. The nose contributes the most to the symptom score and determines about 40% of the score. CONCLUSIONS The exact method of calculation of the symptom score is not critical. All computation methods show the same behavior (increase/decrease). The symptom load index is therefore a useful computation method in all fields exploring pollen allergy and online diaries are a globally applicable tool to monitor the effect of pollen on human health via electronic generated symptom data. However, studies should always consider the variation between different pollen seasons, years and biogeographical regions.