[Epidemiological survey of allergic rhinitis in steppe area of Xilingol League, Inner Mongolian of China].

Objective:To investigate the epidemiologic feature of allergic rhinitis （AR） in the grassland area of Xilin Gol League, in Inner Mongolia, including prevalence rate, clinical characteristics and main allergens, so as to provide scientific evidence for the prevention and treatment of AR. Methods:From May to August of 2015, in strict accordance with the requirements of epidemiological investigation, A multi-stage, stratified， random and cluster sampling method was adopted to investigate the population in three areas of Xilingol Grassland in Inner Mongolia （Xilinhot, Erlianhot and Duolun）, with a face to face questionnaire used to investigate the general situation, the main clinical symptoms and related symptoms of AR and the combined. Simultaneously, the skin prick test （SPT） of 10 common grassland allergens was carried out, and the gravity sedimentation method was used to monitor the daily pollen types and quantity in the area.SAS 9.4 software was used for data analysis． Results:A total of 2878 subjects in the cluster sample completed the questionnaire survey and allergen detection. The positive rate of SPT was 41.10% （1179/2787）, the self-reported prevalence rate of AR was 39.96%（1150/2878） and confirmed prevalence rate of AR was 22.72%（654/2878）. The most obvious clinical symptoms of AR were sneezing （91.13%, 1048/1150） and itchy nose （85.65%, 985/1150）. The most obvious clinical symptoms of ocular were itchy （55.13%, 634/1150） and tearing（42.96%，494/1150）. Fatigue and somnolence were prominent among other symptoms associated with AR. Among comorbidities, AR combined with conjunctivitis accounted for 60.52% （696/1150）, AR combined with asthma accounted for 13.57% （156/1150）. The major allergens of AR from high to low were Artemisia pollen, Chenopodium pollen, and Humulus pollen. The peak of AR symptoms mostly occuredin August.， and the peak period of allergic rhinitis symptoms coincided with the peak period of pollen quantity. Conclusion:The prevalence rate of AR in is extremely high due to the high seasonal pollen exposure in steppe area of Xilingol League in Inner Mongolian. Artemisia pollen is the main sensitized allergen.