Abstract: Background　Studies show that cerebral free radicals accumulate during daytime wakefulness and are removed during sleep. The removal of excess free radicals during sleep is fulfilled by reducing the production of free radicals and increasing the efficiency of endogenous antioxidant mechanisms. However, the relationship between oxidative stress and insomnia is unclear yet.Objective　To examine the levels of free radicals and antioxidant enzymes in patients with nonorganic insomnia, and to evaluate whether they have a correlation with nonorganic insomnia.Methods　This study was implemented from January 2015 to March 2017，following a case-control design.From Sleep Disorders Department，Xinjiang Mental Health Center，78 inpatients and outpatients with nonorganic insomnia〔diagnosed in accordance with the corresponding criteria included in ICD-10，in combination with Pittsburgh Sleep Quality Index （PSQI） total score ≥7 〕 were invited，and other 76 healthy workers of this hospital were invited as the controls.The plasma levels of catalase （CAT），glutathione peroxidase （GSH-PX），malondialdehyde （MDA） and superoxide dismutase （SOD） were compared between the two groups.Results　There were no significant differences in the distribution of age and sex，prevalence of smoking and drinking between the two groups （P>0.05）．The nonorganic insomnia group had higher PSQI total score and factor scores than the control group （P<0.001）．The levels of CAT，GSH-PX，and SOD activity of the nonorganic insomnia group were lower than those of the control group（P<0.001），but the level of MDA activity was similar in both groups（P>0.05）.Conclusion　Nonorganic insomnia patients have increased oxidative stress level，suggesting that oxidative stress may be involved in the development of nonorganic insomnia.

Key words: Insomnia, Sleep disorders, Oxidative stress, Case-control studies

摘要： 背景　研究表明，大脑的自由基在日间醒觉状态时进行积累，在睡眠期间进行清除。睡眠期间过多自由基的清除是通过减少自由基的生成及增加内源性抗氧化机制完成的，但氧化应激与失眠症之间的关系目前仍未阐明。目的　了解非器质性失眠症（失眠症）患者自由基、抗氧化酶水平的变化，探讨其是否与失眠症的发病有关。方法　采用病例对照研究设计，选择2015年1月—2017年3月在新疆精神卫生中心睡眠医学科就诊，符合国际疾病分类标准编码（ICD-10）失眠症的诊断标准、匹兹堡睡眠质量指数（PSQI）总分≥7分的门诊及住院患者78例作为失眠症组，选择同期76名健康人作为对照组。比较两组血清过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GSH-PX）、丙二醛（MDA）及超氧化物歧化酶（SOD）的活性水平。结果　两组性别、年龄、吸烟情况、饮酒情况比较，差异无统计学意义（P>0.05）。失眠症组PSQI总分及各成分评分高于对照组，差异有统计学意义（P<0.001）。失眠症组CAT、GSH-PX、SOD的活性水平低于对照组，差异有统计学意义（P<0.001）；失眠症组MDA的活性水平与对照组比较，差异无统计学意义（P>0.05）。结论　失眠症患者氧化应激水平异于常人，提示氧化应激可能参与失眠症的发病过程。

关键词: 失眠症, 睡眠障碍, 氧化性应激, 病例对照研究