Impact of pollen levels on the use of health services in Santiago de Compostela

Abstract

Objective. To find out the impact of grass pollen levels on the use of primary care consultations for episodes of allergic rhinitis and asthma in Santiago de Compostela throughout a year.

Method. A descriptive ecological study was carried out. The dichotomous variable “overconsultation” (weeks with a higher than expected number of consultations) was compared with pollen levels. In addition, episodes of asthma or allergic rhinitis were correlated with pollen counts, air pollutants and atmospheric conditions. The variables that were found to be associated were analysed by logistic regression.

Results. “Overconsultation” caused by allergic rhinitis was significantly associated with high levels of grass pollen. A strong direct association was found between the number of episodes of allergic rhinitis and both pollen count and ozone levels. Pollen levels significantly influenced the existence of “overconsultation”, but no relationship was found between “overconsultation” and ozone levels. There was a significantly higher number of visits for asthma when grass pollen levels were high. A strong direct association was observed between episodes of asthma and both pollen count and ozone levels. These two factors significantly influenced the existence of “overconsultation”, but no relationship was found between “overconsultation” and grass pollen levels.

Conclusions. The grass pollen level appears to increase the likelihood of primary care “overconsultation” for allergic rhinitis. However, no evidence was found that high grass pollen levels increase the number of primary care consultations caused by asthma.