Abstract: To investigate the relationship between superoxide dismutase（ SOD ） and malondialdehyde（ MDA ） and obstructive sleep apnea hypopnea syndrom (OSAHS) accompanied by hypertension. Methods： Thirtyone OSAHS patients without hypertension, twentynine OSAHS patients with hypertension and twentyfive healthy controls were enrolled in this study. The levels of MDA and SOD were measured respectively by thiobarbituric aicd and xanthine oxidese method. Results： Compared with the healthy controls, the level of SOD in OSAHS patients was decreased and the level of MDA increased. The SOD/MDA ratio in the OSAHS patients with hypertension decreased significantly, and it negatively correlated with the apnea hypopnea index (AHI) and the longest duration of apnea/hypopnea and positively correlated with the lowest oxygen saturation. Conclusion： The maladjustment of SOD/MDA ratio may play an important role in the occurrence of OSAHS with hypertension.

Key words: obstructive, Sleep apnea hypopnea syndrome, Superoxide dismutase, Malondialdehyde, Hypertension