Effect of continuous positive airway pressure treatment on elderly Chinese patients with obstructive sleep apnea in the prethrombotic state

Objectives To characterize the prethrombotic state ( PTS) in elderly Chinese patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and the effect of nasal continuous positive airway pressure (nCPAP) ventilation on their PTS.Methods Forty-one elderly patients with moderate and severe OSAHS were enrolled into the OSAHS group and underwent nCPAP treatment. Their blood samples were drawn at 6:00 am and 4:00 pm before and during nCPAP treatment, respectively, to test hemocrit, platelet aggregation (PAG), whole blood viscosity (WBV), plasma fibrinogen (fng), prothrombin time (PT) and activated partial thromboplastin time (APTT). All blood factors were also tested in a control group consisting of 32 healthy elderly Chinese with neither OSAHS nor cerebrocardiac vascular disease.Results In the OSAHS group there was a significantly higher hemocrit, WBV, fng, and a significantly shorter PT and APTT at 6:00 am compared to 4:00 pm before nCPAP treatment, while there was no significant difference among all blood test factors between 6:00 am and 4:00 pm on day 30 of the nCPAP treatment. In the OSAHS group, the hemocrit, WBV, PAG and plasma fng were significantly lower and the PT and APTT were significantly longer at 6:00 am on day 30 of the nCPAP treatment compared to 6:00 am before the nCPAP treatment. A significantly lower hemocrit, but a much longer PT and APTT were observed at 4:00 pm on day 30 of the treatment, compared with 4:00 pm before the treatment. No significant difference among the blood test factors was found between 6:00 am and 4:00 pm blood in the control group or between the control and OSAHS groups after 30 days of nCPAP treatment.Conclusion In elderly Chinese OSAHS patients, PTS could be effectively eliminated by nCPAP treatment.

Sleep deprivation reorganizes the dynamic configurations of default mode network activity during recovery sleep

Sleep deprivation causes disturbances of the neural activity, leading to the impairment of brain functions. However, the exact mechanism of sleep deprivation and how it affects the dynamics of brain activity during the recovery sleep remains unclear. In the current study, we performed sleep deprivation experiments on ten adult rats, and recorded the local field potentials from default mode network(DMN) regions during sleep before and after sleep deprivation. The DMN dynamics was assessed with the configurations of coactive micropatterns(CAMPs) using our previously proposed CAMP method. Our analysis revealed that the effects of sleep deprivation on DMN dynamics in the slow-wave sleep(SWS) state and the rapid eye-movement sleep(REM)state were disparate. Dynamic configurations of DMN activity in the SWS state were significantly impaired after sleep deprivation, with increased occurrence of low-activity CAMP and reorganized transition structure across three CAMPs. Moreover,enhanced functional connectivity and improved efficiencies in all CAMP networks were observed during the SWS state in the recovery sleep. However, there were no significant alterations in either DMN dynamics or CAMP network structures in the REM sleep state after sleep deprivation. Our results described the alterations of DMN dynamics in different sleep states after sleep deprivation, and illustrated the differential effects of sleep deprivation on two sleep states. These findings demonstrated the underlying neural mechanisms of the effects of sleep deprivation on DMN activity during sleep and increased our understanding of the physiological roles of the DMN in maintain sleep homeostasis after sleep deprivation.