Posted by LostBoyinNCBecksDark on October 11, 2007, at 18:56:47
In reply to Re: What my sleep doctor said, posted by LostBoyinNCBecksDark on October 11, 2007, at 18:49:37
http://www.annals-general-psychiatry.com/content/4/1/13
"The two main factors suspected to be responsible for depressive symptoms in OSA are sleep fragmentation and oxygen desaturation during sleep. Sleep fragmentation is a direct consequence of the recurrent microarousals associated with the apneas and hypopneas, and the nocturnal hypoxemia is due to the intermittent drops in oxygen saturation caused by the respiratory events [47]. Sleep fragmentation is the primary cause of EDS in OSA patients, and is suggested to result in the depressive symptomatology in OSA. This last perspective gains support from the finding that EDS as measured by the Epworth Sleepiness Scale (ESS) and the Maintenance of Wakefulness Test (MWT) was found to be correlated with higher depression scores on the Hospital Depression Scale (HAD-D) in 44 patients with OSA [48]. Furthermore, a Canadian study on 30 OSA patients showed a significant correlation between the severity of psychological symptoms on SCL-90 and less total sleep time, as well as percentage of wake time after sleep onset and ESS scores [49]. With respect to hypoxemia, Engleman et al. noted in a recent review that the effect size of cognitive impairment in OSA correlated highly with severity of hypoxic events, ranging from .3 standard deviations for milder levels of AHI to 2–3 standard deviations for higher levels of AHI [50]. Recently, preliminary imaging data suggests that hypoxemia related to OSA might also play a role in impacting mood. Cerebral metabolic impairment resulting from recurrent nocturnal hypoxemia in OSA have had previously been observed in several imaging investigations on OSA [51-53]; independently, white matter hyperintensities (WMH) have been linked to depressive symptomatology in studies on affective disorders [54-58]. Aloia et al. reported in a small sample of older patients with OSA more subcortical WMH in the brain MRI of patients with a severe OSA as compared to those with minimal OSA, and a tendency for a positive correlation between these subcortical hyperintensities and depression scores on the Hamilton Depression Scale [59]."
poster:LostBoyinNCBecksDark
thread:788423
URL: http://www.dr-bob.org/babble/20071009/msgs/788551.html