睡眠结构及氧化应激与阻塞性睡眠呼吸暂停低通气综合征患者认知障碍的关系

Role of oxidative stress and sleep structure on cognitive dyfunction in patients with obstructive sleep apnea-hypopnea syndrome

目的:通过比较睡眠呼吸暂停低通气综合征(OSAHS)患者血清丙二醛(MDA)及超氧化物歧化酶(SOD)水平与健康对照组的差异,探讨OSAHS患者认知功能障碍发生中的生物学作用。方法:选择经多导睡眠图确诊的OSAHS患者28例及健康体检者16例进行睡眠检测,使用蒙特利尔认知评估(MoCA)评分检测认知功能,用镉分光比色法测定清晨血清SOD和MDA浓度,并比较SOD、MDA与缺氧指标、认知功能分数的关系。结果:OSAHS组认知能力总分及其亚项延迟回忆、计算力、词语流畅性得分均显著低于对照组(均P<0.01),血清MDA浓度明显增高(P<0.01),血清SOD浓度明显降低(P<0.01)。MDA及SOD浓度与缺氧指标即脉搏血氧饱和度(SaO2)<80%占总睡眠时间的百分比,认知能力总分及其亚项延迟回忆、计算力、词语流畅性有显著相关性(P<0.05)。结论:低氧血症和睡眠结构紊乱导致的氧化应激可以损害神经系统,可能是OSAHS患者认知功能受损的生化基础。

Objective： To investigate the possible biochemical mechanism of cognitive dyfuntion in patients with obstructive sleep apnea-hypopnea-hypopnea syndrome （OSAHS）. Methods： Polysomnography was administered to twenty-eight patients with OSAHS and sixteen education and BMI-matched controls, all the cases were measured serum superoxide dismutase （SOD） and malondialdehyde （MDA） level by spectrophotometry and underwent the Montreal Cognitive Assessment. Results： The scores of MoCA and its subitems including calculation,language and delay recall in the patients with OSAHS were significantly lower than those in the controls （P 〈 0.01 ）. The serum MDA level in patients was significantly higher than that in the controls （P 〈 0.01 ）. The serum SOD level in patients was significantly lower than that in the controls（ P 〈 0.01 ）. The level of MDA and SOD was significantly correlated with the percentage of time during sleep spent with an oxygen saturation below 80% and the scores of MoCA and its subitems including calculation,language and delay recall （ P 〈 0.05 ）. Conclusion： Oxidative stress may play an important role in cognitive impairment in patients with OSAHS.