Comparison of Psychiatric Symptoms in Patients With Obstructive Sleep Apnea, Simple Snoring, and Normal Controls

Association between snoring frequency and male serum testosterone: Findings from the 2015-2016 National Health and Nutrition Examination Survey

BACKGROUND

This study aimed to assess the association between snoring frequency and male serum testosterone levels.

METHODS

We analyzed data from the 2015 to 2016 National Health and Nutrition Examination Survey. Snoring frequency was relied on self-report, and was divided into never, rarely (1-2 nights a week), occasionally (3-4 nights a week), or frequently (5 or more nights a week) groups. Multivariable analysis controlling for age, race, waist circumference, total cholesterol, diabetes, and hypertension was used to evaluate the association between snoring frequency and male serum testosterone. Furthermore, we performed the subgroup analyses stratified by age and waist circumference.

RESULTS

Our analysis included 1900 participants. In the fully adjusted model, only frequent snoring was inversely associated with male serum testosterone (β -0.053, 95% CI -0.101 to -0.006, P = 0.028); According to the subgroup analysis stratified by age, only in 40-59 years group, frequent snoring was inversely associated with male serum testosterone in the fully adjusted model (β -0.113, 95% CI -0.196 to -0.031, P = 0.007). As for the subgroup analysis stratified by waist circumference, our results showed only in the waist circumference ≥102 cm group (abdominal obesity), frequent snoring was inversely associated with male serum testosterone (β -0.133, 95% CI -0.216 to -0.05, P = 0.002).

CONCLUSIONS

Frequent snoring (5 or more nights a week) is inversely associated with male serum testosterone levels, especially in those aged 40-59 years and those with abdominal obesity.

Relationship between the Spectral Power Density of Sleep Electroencephalography and Psychiatric Symptoms in Patients with Breathing-related Sleep Disorder

Objective

Patients with breathing-related sleep disorder (BRSD) often complain of psychiatric symptoms such as depression in addition to snoring, excessive sleepiness, and disturbed sleep. However, the relationship between psychiatric symptoms and severity of sleep apnea in BRSD is controversial. We conducted this study to investigate the relationship between psychiatric symptoms and sleep electroencephalography (EEG) findings in BRSD patients using spectral analysis.

Methods

All participants underwent polysomnography and evaluation using Symptom Checklist-90-Revised (SCL-90-R) scale. We analyzed the absolute spectral power density values of standard EEG frequency bands in the participants (n = 169) with BRSD during the non-rapid eye movement (NREM) sleep period. We performed correlation analysis between the domain scores of SCL-90-R scale and the absolute values of the EEG frequency bands.

Results

Significant positive correlation was observed between the absolute spectral power density values in the slow oscillation band and the degree of paranoid ideation (r = 0.226, p = 0.028) and depression (r = 0.216, p = 0.044) in SCL-90-R. The multiple linear regression model showed that higher paranoid ideation domain score (B = 0.007, p = 0.020), younger age (B = −0.011, p < 0.001), and female sex (B = 0.213, p = 0.004) were associated with higher slow oscillation power during NREM sleep.

Conclusion

The results of the present study suggested a relationship between sleep EEG and psychiatric symptoms in patients with BRSD. This relationship needs to be validated with further studies.

Association between snoring and depressive symptoms in adolescents

While previous studies have suggested that snoring may be associated with depressive symptoms and suicidality in adults and preschool children, there have been no investigations in non-clinical adolescent populations. This study aimed to demonstrate the association between snoring and depressive symptoms/suicidality in adolescents. This survey study recruited 8530 students (grades 7-11) and examined depressive symptoms, suicidality, snoring frequency, daytime sleepiness, sleep duration, and presence of insomnia by questionnaires. Correlation analyses, multiple linear regression analyses and mediation analyses were performed to determine the association between snoring frequency and depressive symptoms/suicidality. The study population included 8080 students (16.73 ± 1.09 years old). Snoring frequency was positively correlated with depressive symptoms and suicidality. Snoring frequency was associated with depressive symptoms and suicidality when adjusted for age and sex, and the association remained significant after additionally adjusting for sleep duration, insomnia, and daytime sleepiness. When depressive symptoms were included as a predictor of suicidality, snoring frequency showed no significant predictive value. Mediation analysis confirmed that depressive symptoms mediate the association between snoring frequency and suicidality. Our findings suggest that self-reported complaints of snoring are associated with increased depressive symptoms and suicidality in adolescents independently of sleep duration, insomnia, and daytime sleepiness, and the connection between snoring and suicidality is mediated by depressive symptoms. These data underscore the importance of identifying snorers among adolescents and screening for depression and suicidal ideation in this population.

Investigation on the Effect of Oral Breathing on Cognitive Activity Using Functional Brain Imaging

Oral breathing directly affects behavioral performance and dental health. Various relationships between oral breathing and periodontal disease have been well-described. However, the effect of oral breathing on cognitive performance remains unclear. This study aimed to investigate the effects of oral breathing on cognitive function using functional magnetic resonance imaging (fMRI). Twenty-two healthy participants (mean age, 22.27 ± 1.42 years) performed a two-back (2B) working memory fMRI task using a 3T MRI scanner while breathing through their oral or nasal passage. Functional activity analysis was performed using a statistical parametric mapping software package. One-sample group analyses were performed in 2B > Rest contrast. Functional connectivity analysis was conducted using MATLAB-based imaging software. Mixed ANOVA analysis was performed. The results showed more brain activation and connection during nasal breathing than during oral breathing. For Nasal > Oral contrast, various functional connections are known to have a significant relationship with working memory, including the left cerebellum, left and right inferior parietal gyrus. This can be significant evidence to demonstrate that oral breathing is an inappropriate method for intellectual activity using brain imaging techniques. Therefore, this study suggests that changing various habits related to oral breathing is important for cognitive function.

Difference in spectral power density of sleep EEG between patients with simple snoring and those with obstructive sleep apnoea

Patients with simple snoring (SS) often complain of poor sleep quality despite a normal apnoea-hypopnoea index (AHI). We aimed to identify the difference in power spectral density of electroencephalography (EEG) between patients with SS and those with obstructive sleep apnoea (OSA). We compared the absolute power spectral density values of standard EEG frequency bands between the SS (n = 42) and OSA (n = 129) groups during the non-rapid eye movement (NREM) sleep period, after controlling for age and sex. We also analysed partial correlation between AHI and the absolute values of the EEG frequency bands. The absolute power spectral density values in the beta and delta bands were higher in the OSA group than in the SS group. AHI also positively correlated with beta power in the OSA group as well as in the combined group (OSA + SS). In conclusion, higher delta and beta power during NREM sleep were found in the OSA group than in the SS group, and beta power was correlated with AHI. These findings are microstructural characteristics of sleep-related breathing disorders.