Objective  To investigate the epidemiological characteristics of allergic asthma in spring and the risk factors in Gobi Desert of Gansu Province.

  Methods  A total of 2 000 patients with asthma were sampled by cluster sampling in Dongfeng Farm District of Gansu Province. Self-made questionnaires were distributed to them. A total of 320 patients diagnosed as allergic asthma were selected in observation group, and 288 patients with non-allergic asthma in the sampling group were selected as control group. The general information, onset time and symptoms of patients in the two groups were compared. Their epidemiological characteristics and influencing factors were analyzed.

  Results  The number of questionnaires distributed in this study was 2 000 copies, 1 867 valid questionnaires were collected, among which 320 cases (16.00%) were allergic asthma patients. There were no significant differences in nationality, occupation and age distribution between two groups (P>0.05). There were statistically significant differences in the distribution of gender and education level between the two groups (P < 0.05). Univariate analysis showed that acute respiratory tract infection history, immune factors, food allergy, other allergic factors, environmental factors, paint exposure history, passive smoking history, automobile exhaust exposure history, oil smoke exposure history, genetic factors and asthma history were the influencing factors of spring allergic asthma attack (P < 0.05). The more frequent onset time of patients in the two groups were at midnight, in early morning, before sleeping and in the afternoon, and patients in the two groups had abnormal symptoms in nose, pharynx and eyes, mainly manifested as runny nose, nasal congestion, sneezing, nasal itching, pharynx itching and eye itching.

  Conclusion  There are many pathogenic factors of allergic asthma in spring in Dongfengchang area of Gansu Province (Gobi Desert area), so patients and their family numbers should be aware of the pathogenic factors and avoid contact with allergens so as to reduce the onset of seasonal asthma.