Impact of environmental factors on the epidemiology of eosinophilic esophagitis in southwestern Europe (2007-2020)

BACKGROUND: Eosinophilic esophagitis (EoE) is a disease characterized by symptoms of esophageal dysfunction and at least 15 eosinophils/hpf in the esophagus. Other systemic and local causes of esophageal eosinophilia should be excluded. OBJECTIVES: The study objectives were to examine the annual epidemiology of EoE for 14 consecutive years, investigate whether there is a relationship between the count of aeroallergens and the incidence of EoE for 12 years, evaluate whether there are family ties between the patients with EoE, and determine whether there are cases of EoE that are triggered or exacerbated by pollens. METHODS: We conducted a prospective, descriptive, and analytic study in patients with EoE for 14 years (2007-2020). The study variables were age, sex, relatives with EoE, time of evolution of the symptoms until diagnosis of the disease, and symptoms. We examined incidence and prevalence, annual counts of aeroallergens for 12 years, and number of diagnoses per year (in 2007-2020). We studied patients with active EoE (in April-July) and EoE in remission (in August-March) for 2 consecutive years. Exacerbations were investigated by measuring symptoms using a visual analog scale of 1 to 10. RESULTS: Of the 366 patients with EoE (studied from 2007 to 2020), 83.5% were atopic, with respiratory allergy and 28% had a food allergy. Their mean age was 35 years. The time of evolution of the symptoms was more than 6 years. Only 11% of the patients had a degree of kinship. Of the 366 patients, 87% had dysphagia, 27% had had impactions, and 12.5% had other symptoms of esophageal dysfunction. We found a positive correlation between the incidence of EoE and Platanaceae pollens. We did not detect any case of EoE triggered or exacerbated by pollens. CONCLUSIONS: The epidemiology of EoE in southwestern Europe continues to grow. We have corroborated the relevant impact of the environment on genetics. Future studies will clarify the possible relevance of Platanaceae pollens in the increased epidemiology of EoE. The role of grass and Oleaceae pollens in triggering EoE is limited by having a short pollination in time.