RESUMO
Background: Tension-type headache (TTH) is the most common primary headache. Obstructive sleep apnea (OSA) and sleep bruxism (SB) are two of the most common sleep disorders; however, the relationship between TTH, OSA, and SB has not been conclusively proved in the literature. The objective of our study was to estimate potential associations with OSA and SB in TTH subjects. Methods: 108 adult individuals who underwent polysomnography (vPSG) were included, and the group was divided into two subgroups: TTH (n = 34) and control (n = 74). The International Classification of Headache Disorders (ICHD-3) guidelines were used to diagnose TTH. OSA and SB diagnoses were based on vPSG examination with electromyographic (EMG) recordings and the American Academy of Sleep Medicine (AASM) criteria. The results were analyzed, where p < 0.05 was considered to be statistically significant. Results: In the TTH group, the incidence of SB was more than two times lower than the control (OR = 0.41, 95% CI: 0.17-0.96, p < 0.05). However, the incidence of severe SB (BEI > 4) was similar in the TTH and control groups (OR = 0.54, 95% CI: 0.21-1.35, p > 0.05). Additionally, phasic and tonic SB episodes were less frequent in the TTH group compared to the controls (p < 0.05). The mean apnea-hypopnea index (AHI) was not significantly different between the TTH and control groups (p > 0.05). The sleep architecture and respiratory disturbances did not differ between the examined groups (p > 0.05). Conclusions: SB is not a risk factor for TTH. Moreover, severe SB is not connected with TTH. OSA is not a risk factor for TTH. Sleep quality did not differ between both groups during PSG; therefore, TTH may not change sleep structure. The mechanism of these findings is still unclear, and further studies should explain in detail the association between TTH and OSA.
RESUMO
Introduction: Comorbid insomnia and obstructive sleep apnea (COMISA) is not a well-identified sleep disorder, despite having a significant impact on health. This study investigates the relationship between sleep bruxism (SB) and sleep architecture in patients with COMISA, obstructive sleep apnea (OSA), and in those without any sleep disorders. Methods: 119 patients were included in the study and divided into three groups: OSA, COMISA, and a control group. Polysomnographic (PSG) examination provided parameters related to sleep architecture, OSA, and characteristics of SB. Results: The bruxism episode index (BEI) and other SB parameters were not found to be statistically different between the three groups (p > 0.05). There was no statistical difference in measured sleep architecture between the COMISA and OSA groups (p > 0.05). In comparison to the control group, participants in the COMISA group were found to have an increased apnea-hypopnea index (AHI), oxygen desaturation index (ODI), respiratory disturbance index (RDI), all arousals (AA), and respiratory arousals (RA) (p < 0.05). Among COMISA patients, AA and RA were shown to have a positive linear correlation with the number of bradycardia events per hour (r = 0.49, r = 0.48, p < 0.05). Conclusions: SB does not occur in patients with COMISA more frequently than in patients with OSA or those without any sleep disorders. PSG parameters are not specific for COMISA; therefore, in order to differentiate this disorder from OSA alone, a comprehensive patient assessment has to be performed.