To know any disease well is to have knowledge and awareness of the possibility of overlapping sleep disorders

Internet addiction and sleep quality: a response to Jahan et al. (2019)

Irregular sleep–wake cycle associated with malignant brain tumor in an adolescent Abstract We report an adolescent case of malignant brain tumor who presented with an irregular sleep–wake cycle as the first significant clinical symptom. The patient was referred to us with a 1-year history of irregular sleep–wake cycle. Subsequently, she was diagnosed with a brain tumor in left temporal lobe, which severely compressed the brain stem. Postoperatively, her sleep–wake cycle normalized, suggesting that the tumor caused reversible dysfunction of the circadian rhythm. Irregular sleep–wake rhythm is most commonly seen in elderly with neurodegenerative disorders. This case suggests that organic causes should be considered when an irregular sleep–wake pattern is seen in adolescents.

Cosleeping and sleep problems in children: a systematic review and meta-analysis Abstract There exist inconsistent findings about the relation between cosleeping and sleep problems in children. We conducted a meta-analysis to assess these relations and compared their cross-cultural differences. We searched the EMBASE, PsycARTICLES, PsycINFO, PubMed, ScienceDirect, and Web of Science databases. A random effect model was used, and subgroup analysis by culture group was performed. By including fifteen qualified studies, this meta-analysis revealed that increased bedtime resistance, sleep anxiety, night waking, and parasomnia were shown from children cosleeping with others. Cosleeping children from the West performed more bedtime resistance and night waking, while those children from the East showed more parasomnia. In general, cosleeping is associated with several sleep disturbances for children, including bedtime resistance, sleep anxiety, night waking, and parasomnia, and the cultural differences do exist between the West and East. The findings provide initial evidence of the influence of cosleeping on children’s sleep problems. More studies on the related topic are needed from diverse cultures in the future.

Effect of ramelteon on insomnia severity: evaluation of patient characteristics affecting treatment response Abstract We conducted a multicenter, open-label, observational study to evaluate the effectiveness and safety of ramelteon in patients with insomnia, and patient characteristics affecting treatment response in routine clinical practice. Eligible patients were aged ≥ 20 years, had a diagnosis of insomnia with difficulty falling asleep, and were scheduled to receive ramelteon 8 mg/day for 12 weeks. The primary objective was to evaluate the relationship between changes in insomnia severity [measured by the Insomnia Severity Index (ISI)] and patient characteristics. Changes in the physical (PCS-8) and mental (MCS-8) components of the Short Form-8 (SF-8), and safety were also investigated. 1527 patients received therapy; 40.5% were aged ≥ 65 years and 29.7, 56.9, and 13.4% had mild, moderate, or severe insomnia, respectively. At week 12, significant improvements in ISI score [mean change (standard deviation) from baseline, − 5.0 points (6.3); p < .0001], PCS-8 score [+ 2.40 points (8.71); p < .0001], and MCS-8 score [+ 3.68 points (9.47); p < .0001] were observed. Factors affecting ISI response or remission (based on adjusted odds ratios) included age ≥ 75 years, shorter disease duration, no alcohol intake, being employed full time, not taking concomitant medication for insomnia, and taking ramelteon more than 1 h before bedtime. In total, 5.9% of patients reported adverse drug reactions. In routine clinical practice, 12 weeks’ therapy with ramelteon was effective at improving insomnia severity, with no new safety concerns identified. Several patient characteristics were found to influence response to therapy. Clinical trial identifier: UMIN000013271

A survey on social jetlag in Japan: a nationwide, cross-sectional internet survey Abstract Misalignment between an individual’s circadian phase and his/her environment due to social imposition is called social jetlag (SJL). SJL has emerged as a public health concern, as it contributes to an unhealthy lifestyle and adverse health outcomes. This study aimed to elucidate the percentage of SJL in a large Japanese population using the Japanese version of the Munich ChronoType Questionnaire (MCTQ). A total of 10,000 participants responded to a web-based cross-sectional survey, and the final sample comprised 3708 participants (60.1% male; average age 45.1 [SD 13.4] years). SJL was measured by subtracting each participant’s midpoint of sleep on workdays from their midpoint of sleep on free days. The average [SD] absolute SJL (SJLabs) value was 0.91 [0.89] hours, and the percentage of participants with SLJabs of more than 1 h was 40.1%. Our data also showed that SJLabs becomes progressively smaller with advancing age. A considerable number of participants of our Japanese population showed differences in sleep behavior between workdays and free days. Young people in particular commonly oversleep on free days to compensate for the sleep debt accumulated over the workweek because of their late chronotype.

The association of brain lesion locations and sleep parameters in patients with multiple sclerosis: a pilot study Abstract The relationship between sleep and brain lesions remains unknown in patients with multiple sclerosis (MS) and is currently under investigation. Sleep deprivation and reduction in the quality of sleep occur as a result of the direct involvement of the specific central nervous system structure. Therefore, we investigated the relationship between demyelination locations and sleep parameters such as sleep efficiency and respiratory disorders. The polysomnography measurements and brain magnetic resonance imaging (MRI) of 28 patients with relapsing–remitting MS were examined. The MRI results were evaluated using standardized maps to depict voxel-wise probability distribution of demyelination lesion load for patients. First, supratentorial and infratentorial lesion loads were evaluated. Subsequently, the procedure was completed by measuring the lobes and brainstem lesions loads in the brain. There was a negative correlation between the percentage of REM (%) and infratentorial and brainstem lesion loads ( \(\rho\) : − 0.396, − 0.418; p < 0.05). Sleep efficiency was adversely affected due to supratentorial lesion loads but it was not statistically significant (p = 0.054). There was no statistically significant correlation between total brain lesion loads and sleep breathing parameters (p > 0.05). Although sleep-related breathing disorders are commonly seen in MS, this study shows that the polysomnography parameter most affected by brain lesion load distribution is REM sleep.

Blink test results in patients with central sleep apnea syndrome Abstract The aim of the study was to evaluate whether there was a problem in the interneuronal junctions of patients with central sleep apnea using the blink reflex test. Twenty-one (21) patients with central type apneas and/or hipopneas and 21 controls were recruited. The blink reflex test was performed and R1, R2 and contralateral R2 (R3) wave values of both groups were recorded in milliseconds (ms). The results of blink test in patients with central sleep apnea were right side R1 = 9.45 ± 4.35 ms, R2 = 33.35 ± 9.97 ms, R3 = 32.15 ± 10.05 ms and left side R1 = 9.90 ± 3.82 ms, R2 = 31.5 ± 10.5 ms, R3 = 29.00 ± 4.77 ms, (p = 0.49, p = 0.69, p = 0.60, respectively), whereas the results of blink test in controls were right side R1 = 9.25 ± 3.50 ms, R2 = 32.75 ± 11.4 ms, R3 = 32.50 ± 13.12 ms and left side R1 = 7.35 ± 2.6 ms, R2 = 27.75 ± 9.75 ms, R3 = 26.65 ± 14.5 ms. (p = 0.015, p = 0.04, p = 0.035, respectively). All left side (R1, R2, R3) blink reflex of the patients with central sleep apnea was statistically significant prolonged than controls. However, there was no statistically significant difference between women with central sleep apnea and controls regarding all right side (R1, R2, R3) blink reflex. There was statistically significant difference in R1, R2 and R3 waves of left sides blink reflex between two groups. The results may be related to central nervous system damage or/and degeneration in the interneuronal junctions of the brain stem in patients with central sleep apnea syndrome.

Cross-sectional examination of gender differences in depression and anxiety symptoms in patients with obstructive sleep apnea Abstract This study examined the prevalence of depression and anxiety symptoms in OSA patients, and predictors of mood disturbance in male and female patients. N = 344 consecutive OSA patients (mean age 51.6 SD 14.1 years, 176 women) completed the Epworth Sleepiness Scale and the Hospital Anxiety and Depression Scale. 42.3% of females reported significant depressive symptoms compared to 32.7% of males, and 29.7% of females compared to 21.4% of males reported significant anxiety. In women, sleepiness, anxiety, and BMI were significant predictors of depression, whereas only sleepiness and anxiety were significant predictors of depression in males. Obesity was a stronger predictor of depression among women, suggesting a complex interaction between weight, sleep, and depression in female patients.

Indication of dynamic neurovascular coupling from inconsistency between EEG and fMRI indices across sleep–wake states Abstract Neurovascular coupling (NVC), the transient regional hyperemia following the evoked neuronal responses, is the basis of blood oxygenation level-dependent techniques and is generally adopted across physiological conditions, including the intrinsic resting state. However, the possibility of neurovascular dissociations across physiological alterations is indicated in the literature. To examine the NVC stability across sleep–wake states, we used electroencephalography (EEG) as the index of neural activity and functional magnetic resonance imaging (fMRI) as the measure of cerebrovascular response. Eight healthy adults were recruited for simultaneous EEG-fMRI recordings in nocturnal sleep. We compared the cross-modality (EEG vs. fMRI) consistency of functional indices (spectral amplitude and functional connectivity) among five states of wakefulness and sleep (state effect). We also segregated the brain into three main partitions (anterior, middle and posterior) for spatial assessments (regional effect). Significant state effects were found on δ, α and fMRI indices and regional effects on the α and fMRI indices. However, the cross-state EEG changes in spectral amplitude and functional connectivity did not consistently match the changes in the fMRI indices across sleep–wake states. In spectral amplitude, the δ band peaked at the N3 stage for all brain regions, while the fMRI fluctuation amplitude peaked at the N2 stage in the central and posterior regions. In regional connectivity, the inter-hemispheric connectivity of the δ band peaked at the N3 stage for all regions, but the bilateral fMRI connectivity showed the state changes in the anterior and central regions. The cross-modality inconsistencies across sleep–wake states provided preliminary evidence that the neurovascular relationship may not change in a linear consistency during NREM sleep. Thus, caution shall be exercised when applying the NVC presumption to investigating sleep/wake transitions, even among healthy young adults.