Neuropsychological Effects of 2-Week Continuous Positive Airway Pressure Treatment and Supplemental Oxygen in Patients with Obstructive Sleep Apnea: A Randomized Placebo-Controlled Study

Abstract

To determine predictors of neuropsychological functioning in patients with obstructive sleep apnea (OSA) and whether treatment with 2-week continuous positive airway pressure (CPAP) or supplemental oxygen would improve cognitive functioning. Design: Randomized placebo-controlled design. Setting: University-based clinical research center. Patients: Forty-six patients with untreated OSA. Interventions: Two-week CPAP, supplemental oxygen, or placebo-CPAP. Measurements and Results: Participants underwent polysomnography and completed a neuropsychological test battery before and after treatment. Prior to treatment, patients with OSA showed diffuse impairments, particularly in terms of speed of information processing, attention and working memory, executive functioning, learning and memory, as well as alertness and sustained attention. A global deficit score at baseline was positively correlated with percentage of stage 1 sleep (p = .049) only and was not correlated with obesity, daytime sleepiness, depression, fatigue, OSA severity, and the other polysomnography variables. The 3 treatment groups (therapeutic-CPAP, supplemental oxygen, and placebo-CPAP) were compared using repeated-measures analysis of variance (ANOVA). There was no significant Time x Treatment interaction for the global deficit score. When examining individual neuropsychological test scores, two thirds of them improved with time regardless of treatment, although only Digit Vigilance-Time (p = .020) showed significant improvement specific to CPAP treatment. Conclusion:The present results suggest that Digit Vigilance-Time might be the most sensitive neuropsychological test for measuring the effects of the treatments. In general, 2 weeks of CPAP or oxygen-supplementation treatment was insufficient to show overall beneficial cognitive effects, as compared with placebo-CPAP. However, 2 weeks of CPAP treatment might be helpful in terms of speed of information processing, vigilance, or sustained attention and alertness.

Cognitive Impairment and Affective Disorders in Patients With Obstructive Sleep Apnea Syndrome

“…The results show that the frequency of cognitive disturbances is higher among patients with severe OSA. These results correspond with the findings of authors such as Aloia et al Bardwell et al and Ferini-Strambi et al who prove the correlation between severe OSA and decreased levels of general cognitive functioning ( 16 , 21 – 23 ). We are not able to assess the cognitive functioning of the patients with mild and moderate OSA, because their number is too low.…”

“…There is a noticeable prevalence of the severe OSA patients−81% of all OSA patients. This finding could be attributed to the patients' ignorance or underestimation of their medical condition—a tendency widely discussed in the literature ( 8 , 14 – 16 ). Because OSA is hard to diagnose, many clinicians recruit patients for screening who are overweight and obese; these conditions are not directly associated with OSA ( 12 , 13 , 15 ).…”

“…In the current research, the retention-test as part of Luria's test could be used as additional screening method for OSA patients, where low scores would indicate organic CNS abnormalities, which is an exclusion criteria for the current study. The results of a potential longitudinal study devoted to the retention memory ability could be compared with the conclusions made by Lim et al who find deficits of retention memory in OSA patients ( 16 ). The significant cognitive impairment, registered by TMT, Part B and the significant deficit of the memorizing ability indicate that different attention disturbances are highly expected among OSA patients.…”

118. Obstructive sleep apnea and neurocognitive performance – The role of cortisol

“…Indeed, future studies would do well to include healthy control participants and to examine the role of individual differences in cortisol levels within OSA, especially as our study included patients with severe OSA, though the clinical spectrum is far wider. The treatment of OSA with CPAP has been reported to show improvements in some aspects of neuropsychologic function, though findings are inconsistent [56,57]. Similarly, CPAP treatment has been reported to reduce cortisol levels [23,24].…”

Effects of Continuous Positive Airway Pressure on Cognitive Deficits in Middle-aged Patients with Obstructive Sleep Apnea Syndrome

“…The inclusion and exclusion criteria resulted in 148 articles. Of these, 98 were excluded because of an absence of standardized neuropsychological tests, 21 were excluded for no control group, 8 were excluded because healthy volunteers served as controls, 5 were excluded for nonrandomized designs, and 3[ 17 18 19 ] were excluded because effect sizes could not be calculated from the available data. Finally, 13 studies were included [ Figure 1 ].…”