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

ABSTRACT

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.