[Analysis of pollen sensitization characteristics of artemisia allergic rhinitis in three urban and rural areas of Inner Mongolia].

Objective: To investigate the distribution rules of artemisia pollen and the clinical sensitization characteristics of allergic rhinitis (AR) induced by artemisia pollen in three urban and rural areas of Inner Mongolia. Methods: From March to October 2019, in 3 central cities (Chifeng, Hohhot, Ordos) and rural areas of Inner Mongolia, an epidemiological investigation method combining multi-stage stratified random sampling and face-to-face questionnaire survey was adopted to screen suspected AR patients, and skin prick test (SPT) was applied for diagnosis. At the same time, pollen monitoring was carried out in 3 areas to analyze the distribution and clinical sensitization characteristics of artemisia pollen.SPSS26.0 statistical software was used to process all the data. Chi-square test was used to compare rates among different age, sex, region and nationality, Spearman test was used to describe correlation analysis, and pairwise comparison of positive rates among multiple samples was used Bonferroni method. Results: Among the 6 393 subjects, 1 093 cases were diagnosed with AR, and the prevalence of AR was 17.10% (1 093/6 393). Among them, pollen-induced allergic rhinitis, the prevalence of PiAR was 10.97% (701/6 393), accounting for 64.14%(701/1 093).The highest incidence was in the youth group (20-39 years old), accounting for 46.94% (329/701).The diagnosed prevalence was higher in females than in males (11.35% vs. 10.64%, χ2 value 12.304, P<0.001).The prevalence rate of ethnic minority was higher than that of Han nationality (13.01% vs. 10.65%, χ2 value 6.296, P=0.008).The prevalence in urban areas was also significantly higher than that in rural areas (18.40% vs. 5.50%, χ2 value 10.497, P<0.001).There was significant difference in prevalence rate among the three regions in Inner Mongolia (6.06% in Chifeng, 13.46% in Hohhot, 16.39% in Ordos, χ2 value 70.054, P<0.001).The main clinical symptoms of artemisia PiAR were sneezing (95.58%), nasal congestion (91.73%) and nasal itching (89.30%).Allergic conjunctivitis accounted for 79.60% (558/701), chronic sinusitis for 55.63% (390/701), asthma for 23.25% (163/701).The pattern of artemisia pollen sensitization was mainly multiple sensitization, and the frequency of clinical symptoms and clinical diseases induced by hypersensitization with other allergens accounted for more than that caused by single artemisia pollen. The spread period of Artemisia pollen in the three regions was from June to October, and the peak state was in August in summer. The peak time of clinical symptoms in artemisia PiAR patients was about 2 weeks earlier than the peak time of pollen concentration, and the two were significantly positively correlated (R=0.7671, P<0.001). Conclusion: Artemisia pollens are the dominant pollens in late summer and early autumn in Inner Mongolia, and the prevalence of artemisia PiAR is high. Controlling the spread of Artemisia pollens is of great significance for the prevention and treatment of AR.

[Epidemiological investigation of allergic rhinitis in central cities and countrysides of Inner Mongolia region].

Objective: To investigate the prevalence of allergic rhinitis (AR) in 3 central cities (Chifeng, Hohhot, Ordos) and the surrounding rural areas of Inner Mongolia region, and to look for possible risk factors related to the disease. Methods: From March to October of 2019, a multi-stage stratified random sampling epidemiological survey was conducted in Chifeng, Hohhot, Ordos and rural areas. The AR-related factors of the population were obtained in the form of face-to-face questionnaire survey, and the skin prick test (SPT) was taken for the participants. AR disease was diagnosed according to the "Guidelines for the Diagnosis and Treatment of Allergic Rhinitis (2015, Tianjin)". The daily airborne pollen situation in the three regions was monitored during the same period. SPSS 23.0 was used to analyze all survey results. Results: A total of 6 818 questionnaires were recovered, with 6 393 valid questionnaires. The self-reported prevalence of AR was 27.72% (1 772/6 393) and the confirmed prevalence of AR was 17.10% (1 093/6 393). The prevalence of perennial AR was 1.83% (117/6 393) while the prevalence of seasonal AR was 15.27% (976/6 393). The prevalence of AR diagnosed in females was higher than that in males (19.19% vs 15.34%, χ²=16.594, P<0.001) and the prevalence of females in the two age groups of 36-45 years and 46-55 years was significantly higher than that of males (18.17% vs 9.73%, 14.13% vs 7.25%, χ2 value was 23.848, 18.772, respectively, all P<0.001). The prevalence of confirmed diagnoses in ethnic minorities was higher than that of Han nationality, and the prevalence of confirmed diagnoses in urban areas was higher than that in rural areas (23.13% vs 16.20%, 27.27% vs 9.71%, χ2 value was 24.516, 336.024, respectively, all P<0.001). The main nasal symptoms of AR patients were sneezing (91.31%), nasal congestion (85.91%) and nasal itching (85.00%). The most common concomitant disease of AR was allergic conjunctivitis (73.99%). Asthma (OR=6.629), food allergy (OR=3.236), drug allergy (OR=1.786), application of antibiotics (OR=1.553), recent home decoration (OR=2.307), and smoking (OR=1.322) were the AR related risk factors. The highest proportion of SPT positive reactions was Artemisia annua (80.15%). The peak period of clinical symptoms of AR patients in Inner Mongolia region was July to September, which was consistent with the second peak period of airborne pollen monitoring. Conclusions: The prevalence of AR in central cities and the surrounding rural areas of Inner Mongolia region is 17.10%, and Artemisia species is the most important pollen allergen in this area. History of asthma, food allergy, drug allergy, antibiotic use, home decoration and smoking history are the related risk factors for AR.