Research Progress on Insomnia and Microarousal / 中国医学科学院学报

Insomnia is a subjective experience of difficulty in falling asleep and/or maintaining sleep accompanied by the impairment of daytime social functioning due to insufficient sleep quality or quantity to meet normal physiological needs.It has chronic damage to all the human body systems and is the most common sleep disorder.The main mechanism for the occurrence and maintenance of insomnia is the hyperarousal hypothesis,and microarousal,as a cortical arousal,is also involved in the formation of the hyperarousal mechanism.The mechanism and clinical significance of microarousal were reviewed and summarized in this paper in order to guide the clinical work.

Apnea/hipopnea del sueño y bruxismo nocturno / Sleep apnea/hypopnea and night bruxism

Los eventos de apnea o hipopnea durante el proceso del sueño se caracterizan por una disminución o bloqueo de la respiración induciendo a un estado orgánico de hipooxigenación que a su vez induce a microdespertares en reacción fi siológica de protección del organismo. Durante estos eventos, el individuo transita de una fase profunda del sueño a una más superfi cial. La repetición de los eventos de apnea/hipopnea provoca que el sueño no sea reparador física y emocionalmente, además de provocar una hiperactividad motora de los músculos masticadores. induciendo un incremento en la frecuencia e intensidad de movimientos rítmicos masticatorios que eventualmente pueden promover daños musculares, articulares, mucosos y dentales. El incremento de los movimientos rítmicos mandibulares también se observa en bruxismo nocturno, lo que abre la posibilidad que haya un efecto sumatorio entre ellos. Para ambos tipos de padecimientos, la polisomnografía empleada en tiempos modernos es un procedimiento para evaluar las alteraciones del sueño, que puede demostrar que los microdespertares preceden a un incremento de manifestaciones del sistema nervioso autónomo, incluida la hiperactividad muscular, la cual puede provocar alteraciones orgánicas de tipo sistémico, además de episodios de apretamiento y rechinamiento dental (AU)

The events of apnea or hypopnea during the sleep process are characterized by a decrease or obstruction of respiration inducing an organic state of hypooxygenation that in turn induces micro-arousals as a physiological reaction to protect the organism. During these events, the individual transits from a deep sleep phase to a more superfi cial phase. The repetition of apnea/hypopnea events causes a sleep that is nor physically neither emotionally repairing; furthermore inducing a motor hyperactivity of the masticatory muscles which increases the frequency and intensity of rhythmic masticatory movements that can eventually promote muscular, joint (TMJ), mucous and dental damage. That increase of the rhythmic masticatory movements is also observed in sleep bruxism, which leaves open the possibility of observing a summation eff ect with sleep apnea. For this type of conditions, polysomnography is a procedure that assesses sleep disturbances and demonstrates that micro-arousal precedes an increase autonomic changes, including muscle hyperactivity, which eventually could cause organic systemic alterations, as well episodes of clenching and dental grinding (AU)

Upper airway dimensions and sleep efficiency – three‑dimensional imaging analysis and assessment of the nasopharyngeal appliance.

Background: Reduction of upper airway (UA) dimensions during sleep is contemplated to cause reduced sleep efficiency (SE) but a definitive association is not affirmed. Efficacy of nasopharyngeal appliance (NPA) in management of UA resistance syndrome (UARS) has not been compared with mandibular repositioning splint (MRS). This study intended to assess relation of UA dimensions to SE and effectiveness of NPA. Materials and Methods: Research had two phases: Case–control study to determine association between UA and SE; randomized control trial (with independent concurrent trial groups and double‑blind design) to analyze treatment outcome with NPA. Subjects were categorized to three groups of 20 in each: A control group of healthy subjects (Group A); two “Randomly Assigned” sample groups of subjects with reduced SE (Groups B and C). Preliminary questionnaire for sleep analysis, Final data collection sheet (first and second case sheets) were recorded, cephalometric variables analyzed, and diagnostic overnight polysomnography was done to match and confirm selection criteria. Three‑dimensional computed tomography was done to analyze airway dimensions before and after appliance placement. ANOVA and post‑hoc tests were used for statistical analysis of results. Conclusions: Reduced UA dimension during sleep is associated with reduced SE; NPA gives better improvement for UARS than MRS.

Considerações fisiopatológias sobre bruxismo / Hysiopathologic considerations about bruxism

O bruxismo é uma parafunção oral que pode ser incluída nas patologias de causa e/ou efeito multifatorial, relacionada à hiperatividade muscular, extremamente destrutiva pelo atrito dos dentes em movimento parafuncional, adquirida de forma inconsciente, que pode ocorrer durante o dia, todavia, mais frequente durante o sono. Essa patologia, pode provocar desgastes dentais, lesões nas estruturas de suporte, desordens da articulação temporomandibular e cefaléias. Sua natureza é multifatorial e não suficientemente esclarecida, assim estão envolvidos desde fatores psicológicos até alterações físicas. Atualmente, sugere-se uma resposta controlada por neurotransmissores do sistema dopaminérgico, pois além do desgaste dentário o paciente pode apresentar fraturas dentárias, mobilidade, migração patológica, dores musculares e articulares, principalmente, ao acordar. Por sua característica multifatorial o tratamento, muitas vezes, requer atuação de vários profissionais. Sendo assim, é indispensável o amplo conhecimento do cirurgião-dentista sobre os mecanismos fisiológicos envolvidos no desenvolvimento do bruxismo, e sobre as características clínicas, para determinação de tratamentos adequados que resultem em um prognóstico favorável e duradouro. Por conseguinte, a partir desta revisão literária objetiva-se relatar sobre a etiopatogenia, características clínicas e tratamento de bruxômanos.

Bruxism is an oral parafunction that can be included in the pathologies of cause and / or effect of multifactorial, related to muscle hyperactivity, it is extremely injurious by the teeth grinding in parafunctional movement, destructive by the friction of the teeth moving parafunctional, acquired unconsciously, that may occur during the day, however, more frequent during sleep. This disease can generate dental wear; affect dental support structures, temporomandibular joint dysfunction and headaches. The etiology of bruxism is multifactorial and yet unknown. Psychological and even physical alterations factors are linked to it, although, nowadays a controlled answer by neurotransmitters from dopamine receptors system is suggested. Other than abnormal wear patterns of occlusal surface the patient may present jaw and temporomandibular joints pain, especially in the morning. Since its multifactorial characteristics, the treatment requires multidisciplinary professional attention. The surgeon-dentist wide knowledge about the physiology mechanism and clinical characteristics involved in the bruxism development is essential to determine a successful treatment and to obtain a good prognostic. The aim of this study is to discuss the etiology, clinical characteristics and treatment for the bruxers.

Association among daytime sleepiness,serum tnlnor necrosis factor-α levels and microarousal in patients with obstructive sleep apnea hypopnea syndrome / 中国医师进修杂志

Objective To investigate the association among daytime sleepiness,serum tumor necrosis factor(TNF)-α levels and microarousal in patients with obstructive sleep apnea hypopnea syndrome (OSAHS).Methods Forty male patients with OSAHS conformed by apnea hypopnea index(AHI)during sleep monitoring of polysomnography were selected as OSAHS group,15 healthy subjects were selected as control group.The level of serum TNF-α was measured by ELISA.The Epworth sleepiness(EP)scale was used in two groups.Results The level of serum TNF-α in OSAHS group[(18.42±6.23)ng/L]was significantly higher than that in control group[(9.75±3.12)ng/L],P＜0.01.The EP scale and micmarousal index were signifieand yhigher in OSAHS group than those in control group[(16.9±4.7)acores vs(4.5±2.3)dcores,(33.6±16.9)times/h vs(11.3±7.3)times/h,P＜0.01].The EP scale in OSAHS group was positively correlated with the levels of serum TNF-α(r=0.461,P＜0.01),AHI(r=0.443,P＜0.01)and microarousal index(r=0.751,P＜0.01)respectively.The levels of serum'INF-α in patients with OSAHS were also positively correlated with microarousal index(r=0.373,P＜0.01).Conclusions The levels of serum TNF-α and mieroarousal index are increased in patients with 0SAHS.The microarousal related to OSAHS plays an important role on the daytime sleepiness,the unusual levels of serum TNF-α maybe lead to interferen of sleepiness.

Spectral Analysis of Hidden EEG Arousal Activity in Periodic Leg Movements in Sleep without Microarousal / 수면정신생리

OBJECTIVES: Periodic leg movements in sleep (PLMS) might be subdivided based upon whether or not they are associated with visible EEG microarousals (MA). MA is considered to be responsible for nonrestorative sleep and daytime fatigue. The American Sleep Disorders Association's (ASDA) scoring rules for MA based on visual analysis of the EEG changes suggest that MA should last more than 3 seconds. However, it has been suggested that visual analysis may not detect some changes in EEG activity. This study is aimed at measuring changes in EEG spectra during PLMS without MA in order to better understand the arousing response of PLMS. METHODS: Ten drug-free patients (three men and seven women) diagnosed with PLMS by polysomnography were studied. Spectral analysis of the EEG was performed in each patient on 30 episodes of PLMS without MA, chosen randomly across the night in stage 2 non-REM sleep. We applied stricter criteria for MA compared to ASDA, by defining it as a return to alpha and theta frequency lasting at least 1 second. RESULTS: The mean PLMS index was 16.7 10.0. The mean PLMS duration was 1.3 0.7 seconds. Comparison of 4-second EEG activity both before and after the onset of PLMS without MA using independent t-test showed that the movements were associated with significant increase of relative activity in the delta band (p=0.000) and significant decrease of activity in the alpha (p=0.01) and sigma (p=0.000) bands. No significant decrease in the theta (p=0.05), beta (p=0.129), or gamma (p=0.062) bands was found. CONCLUSIONS: PLMS without MA was found to be associated with EEG change characterized by increase in the delta frequency band. This finding seems to be compatible with the hypothesis of an integrative hierarchy of arousal responses of Sforza's. Considering that the subjects had lower PLMS index and shorter PLMS duration than those of the previous study, it is suggested that an even less severe form of PLMS without MA could induce neurophysiologic change, which may potentially be of clinical significance.

Changes of Microarousal in OSAHS Patients Before and After Operation / 中国医师杂志

Objective To explore the value of microarousal in the diagnosis and treatment of obstructive sleep apnea-hypopnea syndrome(OSAHS). Methods 120 snorers were monitored by standard polysomnography(PSG). The overnight PSG recordings were also performed 1 year after operation in 24 patients, who had filled in the Epworth Sleep Score(ESS) before and after treatment, to evaluate the improvement of daytime sleepiness. Results After operation, obstructive sleep apnea of the 24 patients disappeared, their ODI 4 decreased from (52?26)/h to (10?8)/h, microarousal decreased from (28?16)/h to (14?6)/h, and the subjective and objective daytime sleepiness was improved. Conclusion The EEG changes of microarousal with at least 3 seconds in OSAHS patients can be recorded by computerized EEG analysis. Microarousal can serve as an index for daytime sleepiness, and be complementary to AHI in the diagnosis and treatment of OSAHS.