目的:睡眠呼吸暂停低通气综合征(SAHS)是一种常见的睡眠呼吸障碍,可导致脑损伤,也是认知障碍和一些常见疾病的危险因素。对睡眠期间皮质有效连接(EC)的研究可能提供更直接和病理的信息,并为SAHS引起的脑功能障碍提供新的思路。然而,在SAHS患者中很少探索EC,尤其是在不同的睡眠阶段。
方法:为此,通过通宵多导睡眠图(PSG)记录43例SAHS患者和41例健康参与者的六通道EEG信号.符号传递熵(STE)用于测量不同频带中皮层区域之间的EC。前后比(PA)用于根据整体皮质EC评估信息流的前后模式。STE和PA以及个体内标准化参数(STE*和PA*)的统计特征用作分类SAHS严重程度的不同特征集。
结果:尽管跨电极的STE模式相似,发现患者组和对照组之间存在显著差异.PA各阶段的变化趋势在组之间的多个频带中也不同。从STE*和PA*中提取的重要特征分布在多个节奏中,主要是δ,α,和γ。PA*功能集给出了最好的结果,SAHS诊断(二元)和严重程度分类(四向)的准确率分别为98.8%和83.3%。
结论:这些结果表明,SAHS患者在睡眠期间存在皮质EC的改变,这可能有助于表征患者的皮质异常。
OBJECTIVE: Sleep apnea hypopnea syndrome (SAHS) is a prevalent sleep breathing disorder that can lead to brain damage and is also a risk factor for cognitive impairment and some common diseases. Studies on cortical effective connectivity (EC) during sleep may provide more direct and pathological information and shed new light on brain dysfunction due to SAHS. However, the EC is rarely explored in SAHS patients, especially during different sleep stages.
METHODS: To this end, six-channel EEG signals of 43 SAHS patients and 41 healthy participants were recorded by whole-night polysomnography (PSG). The symbolic transfer entropy (STE) was applied to measure the EC between cortical regions in different frequency bands. Posterior-anterior ratio (PA) was employed to evaluate the posterior-to-anterior pattern of information flow based on overall cortical EC. The statistical characteristics of the STE and PA and of the intra-individual normalized parameters (STE* and PA*) were served as different feature sets for classifying the severity of SAHS.
RESULTS: Although the patterns of STE across electrodes were similar, significant differences were found between the patient and the control groups. The variation trends across stages in the PA were also different in multiple frequency bands between groups. Important features extracted from the STE* and PA* were distributed in multiple rhythms, mainly in δ, α, and γ. The PA* feature set gave the best results, with accuracies of 98.8% and 83.3% for SAHS diagnosis (binary) and severity classification (four-way).
CONCLUSIONS: These results suggest that modifications in cortical EC were existed in SAHS patients during sleep, which may help characterize cortical abnormality in patients.