Personalized pollen monitoring and hay fever symptom scores: a feasibility study

Abstract Background. Pollen is a major trigger for allergic symptoms in sensitized individuals. Airborne pollen is usually monitored by Hirst type pollen samplers located at rooftop level, providing a general overview of the pollen distribution in the larger surroundings. In this feasibility study, grass pollen-sensitized subjects monitored the pollen in their direct environment using a portable pollen sampler (Pollensniffer) and scored their symptoms, to study the relation between symptom severity and personal grass pollen exposure. For comparison the symptoms were also correlated with pollen collected by the rooftop sampler. Methods. Nine grass pollen-sensitized individuals were enrolled in this study (May 2018) and asked to monitor personal pollen exposure using a Pollensniffer on their way to school, work or other destination, and to score their symptoms via a mobile app on a scale from 0 to 10. Daily pollen concentrations were collected by a Hirst type sampler at rooftop level. Pollen grains were analysed using a microscope. Results. Three of the four participants with high grass pollen-specific (GPS) IgE (>9.6 kU/l) reported high symptom scores (>4) and an analysis showed a significant correlation (CC) between eye, nose and lung symptoms and the grass pollen counts collected by the Pollensniffer, as well as the daily grass pollen concentrations monitored by the rooftop sampler (CC>0.54). In contrast, the participants with low GPS IgE levels (<9.6 kU/l) reported low symptom scores (<4) and often other sensitizations were present. For these subjects, no significant positive correlations (CC<0.3) of symptoms with either grass pollen collected by the personal or the rooftop sampler were found. Conclusion. Our results show that correlations between the severity of clinical symptoms of grass pollen allergic patients, and airborne grass pollen counts as determined by a personal pollen sampler (Pollensniffer) or a rooftop sampler, is restricted to patients with high GPS IgE levels, high symptom scores and no relevant other sensitizations. Based on the number of subjects included in this feasibility study, no conclusions can be drawn on the performance of the personal pollen sampler in relating symptoms and pollen exposure in comparison with the rooftop sampler.Trial registrationThe study was approved by the Committee Medical Ethics of the LUMC (approval numbers: NL63953.058.17/ P17.304).