ABSTRACT
OBJECTIVE: Obstructive sleep apnea (OSA) has been associated with an elevated cardiovascular risk, increased daytime sleepiness, cognitive decline, and slower electroencephalographic activity (EEG). This study assesses EEG patterns during wakefulness in OSA patients compared to those without sleep-disordered breathing. MATERIALS AND METHODS: This retrospective study analyzed 30 OSA patients with an Apnea/Hypopnea Index (AHI) of 15 or higher, as well as 29 individuals without sleep-disordered breathing (AHI of 5 or lower) who underwent hospital polysomnography and met all inclusion criteria. Sociodemographic and EEG data were obtained from the sleep laboratory database. Blinded EEG analysis was conducted by two observers, assessing activity in the frontal, central, and occipital regions. RESULTS: No significant differences were observed in EEG activity between OSA and non-OSA patients. However, a weak correlation was found between decreased C3 EEG frequency and higher AHI (p = 0.033), as well as increased total sleep time and higher O2 EEG frequency (p = 0.038). Lower amplitudes in C3 (p = 0.043) and O1 (p = 0.031) were correlated with reduced average oxygen saturation. CONCLUSION: Our findings suggest that OSA-related hypoxemia may impact neuronal activity, highlighting the need to address this sleep-disordered breathing in order to potentially prevent the cognitive decline observed in OSA patients.
ABSTRACT
OBJECTIVE: Sleep quality is influenced by multiple factors. Slow-wave sleep and REM sleep play a key role in homeostasis and are useful indicators of sleep quality. Studies indicate that obstructive sleep apnea (OSA) in the supine position correlates with anatomical changes that exacerbate respiratory events and influence the effectiveness of ventilation therapy. This study aimed to evaluate the correlation of body posture with polysomnographic data and adherence of patients using continuous positive airway pressure (CPAP). MATERIAL AND METHODS: This was a retrospective study of patients with OSA who had polysomnography in Rainha Santa Isabel Hospital's sleep laboratory in Torres Novas, Portugal, and met all the inclusion and exclusion criteria. Sociodemographic, polysomnographic, and ventilation therapy variables were collected from that sleep laboratory database between 2015 and 2019. RESULTS: In 30 patients with OSA, residual apnea-hypopnea index (AHIr) and arousal index were lower in the non-supine position compared to the supine position (p value 0.005 and 0.009 respectively). As measures of sleep quality, total sleep time in SWS and REM sleep were greater in the non-supine position compared to the supine position (p value of 0.002 and 0.010 respectively). CONCLUSION: The findings suggest that a supine position significantly impairs sleep quality mainly by increasing the number of respiratory events and associated sleep fragmentation. The findings also suggest that the difference in AHIr between supine and non-supine positions may contribute to non-adherence with CPAP in patients with OSA.
