Abstract: Objective  To build the theoretical basis for the prevention and treatment of obstructive sleep apnea hypopnea syndrome (OSAHS) by comparing difference in clinical features of OSAHS patients between Bai and Han ethnic groups. Methods  A total of 224 patients with OSAHS from Dali area were enrolled, among which 115 were from Han ethnic group and 109 were from Bai ethnic group. The patients were divided into mild, moderate and severe groups according to 2015 Diagnostic and Classification Criteria of OSAHS, and the clinical data of  the patients were collected and analyzed. Results  ①The number of patients with severe OSAHS was significantly greater than that of the mild and moderate OSAHS in both Han and　Bai ethnic groups (P<0.05). ②The severity of OSAHS in Han group was aggravated with the increase of smoking rate. The proportion, drinking rate, BMI and circumference of abdomen of male patients in the severe group were significantly higher than those of mild of OSAHS; The average age of severity of OSAHS was significantly elder than that of moderate of OSAHS (P<0.05). ③The lowest oxygen saturation of Han group in mild OSAHS patients was significantly lower than that in Bai group, the average age of Bai group in moderate OSAHS patients was significantly lower than that in Han group, and the smoking rate of Han group in severe OSAHS patients was significantly higher than that in Bai group (P<0.05).Conclusion  The majority of OSAHS patients in Dali are more severe, while Han people suffer from more severe hypoxia,  Bai group had earlier onset age of moderate OSAHS, and the smoking rate in severe Han OSAHS patients was higher.

Key words: sleep apnea, , obstructive, minority groups; , risk factors