Effect of continuous positive airway pressure treatment on short-term memory performance over 24h of sustained wakefulness in patients with obstructive sleep apnea–hypopnea syndrome

Abnormal interaction between cortical regions of obstructive sleep apnea hypopnea syndrome children

Obstructive sleep apnea hypopnea syndrome negatively affects the cognitive function of children. This study aims to find potential biomarkers for obstructive sleep apnea hypopnea syndrome in children by investigating the patterns of sleep electroencephalography networks. The participants included 16 mild obstructive sleep apnea hypopnea syndrome children, 12 severe obstructive sleep apnea hypopnea syndrome children, and 13 healthy controls. Effective brain networks were constructed using symbolic transfer entropy to assess cortical information interaction. The information flow pattern in the participants was evaluated using the parameters cross-within variation and the ratio of posterior-anterior information flow. Obstructive sleep apnea hypopnea syndrome children had a considerably higher symbolic transfer entropy in the full frequency band of N1, N2, and rapid eye movement (REM) stages (P < 0.05), and a significantly lower symbolic transfer entropy in full frequency band of N3 stage (P < 0.005), in comparison with the healthy controls. In addition, the cross-within variation of the β frequency band across all sleep stages were significantly lower in the obstructive sleep apnea hypopnea syndrome group than in the healthy controls (P < 0.05). What is more, the posterior-anterior information flowin the β frequency band of REM stage was significantly higher in mild obstructive sleep apnea hypopnea syndrome children than in the healthy controls (P < 0.05). These findings may serve as potential biomarkers for obstructive sleep apnea hypopnea syndrome in children and provide new insights into the pathophysiological mechanisms.

Continuous positive airway pressure treatment impact on memory processes in obstructive sleep apnea patients: a randomized sham-controlled trial

OBJECTIVE

The aim of this study was to investigate the changes in a large panel of memory processes after six weeks of continuous positive airway pressure (CPAP) in obstructive sleep apnea (OSA) patients. This randomized controlled trial compared the influence of effective CPAP to sham CPAP over six weeks on different memory processes in OSA patients.

METHODS

The study took place in a sleep laboratory and outpatient sleep clinic in a French tertiary-care university hospital. A total of 36 patients with OSA were randomized to receive either CPAP (n = 18) or sham CPAP (n = 18) for six weeks. Interventions were either effective CPAP or non-effective sham CPAP, for six weeks. All patients underwent an extensive battery of tasks evaluating three separate memory systems, before and after treatment. Verbal episodic memory was tested after forced encoding, procedural memory was tested using simplified versions of mirror drawing and reading tests, and working memory was examined with validated paradigms based on a theoretical model.

RESULTS

The study subjects were 55 ± 11 years of age and 72.2% were male. The mean body mass index was 29.5 ± 4.1 kg/m² and the apnea-hypopnea index was 37.1 ± 16.3/h. Prior to treatment, memory performances of OSA patients were altered. In an intention-to-treat analysis, memory deficits were not significantly improved after six weeks of effective CPAP compared to sham CPAP treatment. Verbal episodic, procedural, and working memory scores were comparable between both groups.

CONCLUSION

Using cautious methodology in comparing effective CPAP to sham CPAP and a well-defined set of memory assessments, we did not find improvement in memory performance after six weeks of treatment.

Cognitive deficits in adults with obstructive sleep apnea compared to children and adolescents

Obstructive sleep apnea (OSA) can negatively affect the patient's physical and psychological functioning, as well as their quality of life. A major consequence of OSA is impaired cognitive functioning. Indeed, several studies have shown that OSA mainly leads to deficits in executive functions, attention, and memory. As OSA can present in all age groups, these associated cognitive deficits have been observed in adults, as well as in children and adolescents. However, these cognitive deficits may have a different clinical picture in young patients compared to adults. In this review, we analyze the most affected cognitive domains in adults and children/adolescents with OSA, as evaluated by neuropsychological and neuroimaging studies. We found that deficits in working memory, attention, or executive functions cognitive domains are found in both adults and children with OSA. However, children with OSA also show changes in behavior and phonological processing necessary for proper development. Moreover, we examine the possible OSA treatments in children and adults that can have a positive influence on cognition, and therefore, improve patients' general functioning and quality of life.