Unmasking the hidden role of sleep bruxism in obstructive sleep apnea patients' sleepiness.

BACKGROUND: Obstructive sleep apnea (OSA) and sleep bruxism (SB) are both sleep-related conditions that may affect sleep architecture and potentially contribute to daytime sleepiness (DS). AIM: This study aimed to explore the association between SB and DS as measured by Epworth Sleepiness Scale in patients with OSA. METHODS: A cross-sectional study was conducted involving 345 patients diagnosed with OSA. The presence of SB was assessed through multidisciplinary clinical examination and audio-video recordings during polysomnography. DS was measured using the Epworth Sleepiness Scale (ESS). Demographic and polysomnographic characteristics were compared between OSA patients with and without SB. Logistic regression models were used to identify significant associations. RESULTS: SB was identified in 13.6% of OSA patients. After adjusting for confounders, OSA patients with SB exhibited significantly higher ESS scores (6.44 vs. 5.28, p = 0.012) and lower percentages of REM sleep (10.23% ± 5.66 vs. 12.82% ± 7.36, p = 0.017). In patients with severe OSA, those with SB showed lower AHI values (60.28 ± 24.39 vs. 69.95 ± 25.25, p = 0.048), increased N3 sleep (18.51% ± 11.49 vs. 13.16% ± 10.13, p = 0.038), and a trend towards reduced REM sleep (9.38% ± 5.17 vs. 11.77% ± 7.08, p = 0.07). CONCLUSION: This study suggests a potential association between SB and daytime sleepiness as measured by ESS score, as well as alterations in sleep architecture, in OSA patients.