Improvements were in daytime vigilance and most neuropsychological deficits but not planning abilities or manual dexterity. These have been shown to be highly correlated with the severity of nocturnal hypoxemia?J Clin Exp Neuropsychol. 1993 Mar;15(2):330-41.
Persistent neuropsychological deficits and vigilance impairment in sleep apnea syndrome after treatment with continuous positive airways pressure (CPAP).
Bédard MA, Montplaisir J, Malo J, Richer F, Rouleau I.
Hôpital du Sacré-Coeur and Université de Montréal, Québec, Canada.
The obstructive sleep apnea syndrome is characterized by nocturnal sleep disturbance, excessive daytime sleepiness and neuropsychological deficits in the areas of memory, attention, and executive tasks. In the present study, these clinical manifestations were assessed in apneic patients before and 6 months after treatment with nasally applied continuous positive airway pressure (CPAP). CPAP treatment was found to restore normal respiration during sleep and to normalize sleep organization. Daytime vigilance greatly improved with treatment but some degree of somnolence as compared to normal controls persisted. Similarly, most neuropsychological deficits normalized with treatment. The exception was for planning abilities and manual dexterity, two neuropsychological deficits that have been found to be highly correlated with the severity of nocturnal hypoxemia. These results raise the possibility that anoxic brain damage is a pathogenic factor in severe obstructive sleep apnea syndrome.
With our jugulars being needed when we are lying down, CCSVI is likely causing nocturnal cerebral hypoxemia. This study was only after six months; there have been reports from the Dake patients that in RRMSers fatigue improvements continued to get better and better even up to a year after treatment.
Here is another one that turned up:
CHEST November 1986 vol. 90 no. 5 686-690
Cognitive impairment in patients with obstructive sleep apnea and associated hypoxemia.
L J Findley, J T Barth, D C Powers, S C Wilhoit, D G Boyd, and P M Suratt
Twenty-six patients with sleep apnea had neuropsychologic testing prior to nocturnal sleep study in a sleep disorders clinic. The cognitive functioning of patients who had sleep apnea with associated hypoxemia was compared to nonhypoxemic patients with sleep apnea. The patients who had sleep apnea with hypoxemia had more severe cognitive impairment than those with sleep apnea without hypoxemia. The hypoxemic patients with sleep apnea had significantly poorer cognitive functioning on four of eight tests (p less than 0.05). In addition, the patients who had sleep apnea with hypoxemia had mean performance scores in the impaired range on measures of attention, concentration, complex problem-solving, and short-term recall of verbal and spatial information. In contrast, the patients who had sleep apnea without hypoxemia had no mean performance score in the impaired range. The degree of hypoxemia during sleep and wakefulness significantly correlated with the degree of overall cognitive impairment as rated by a neuropsychologist; however, measures of sleep fragmentation did not significantly correlate with overall cognitive impairment in patients with sleep apnea. We conclude that patients who have sleep apnea with associated hypoxemia have cognitive impairment which is more severe than those with sleep apnea without hypoxemia.
http://chestjournal.chestpubs.org/conte ... 6.abstract