Relação do cronotipo nos níveis de ansiedade e consumo Máximo de oxigênio em jovens / Relation between chronotype on anxiety levels and maximum oxygen consumption in young people

O presente estudo analisou a relação entre cronotipo, níveis de ansiedade, depressão e estresse, bem como níveis de condicionamento cardiorrespiratório em jovens. Métodos: Foi analisado um total de 36 participantes com idades entre 18 e 28 a nos, saudáveis e que atendessem ao cronotipo matutino e vespertino. Análises de nível de atividade física, consumo máximo de oxigênio, níveis de depressão, ansiedade e estresse foram realizadas com testes específicos. Em todos os cálculos foram utilizados um alfa de p<0.05 para análise estatística. Resultados: O nível de atividade física mostrou que a porcentagem dos matutinos suficientemente ativos foi de 58% comparado com 23.5% dos vespertinos. Mulheres com cronotipo vespertino apresentaram níveis menores de VO2máx quando comparados com as mulheres com cronotipo matutino (p=0.04). Os participantes vespertinos apresentaram níveis maiores de ansiedade (p=0.02) comparados com os matutinos e esses dados foram evidentes nos participantes do sexo feminino onde as mulheres do cronotipo vespertino apresentaram níveis maiores de ansiedade (p=0.03) comparados com mulheres de cronotipo matutino. Conclusão: Portanto, o estudo conclui que indivíduos do cronotipo vespertino apresentaram menores níveis de atividade física e maiores níveis de ansiedade evidenciados principalmente nas mulheres.(AU)

The present study analyzed a relationship between schedule, anxiety, depression and stress levels, as well as cardiorespiratory fitness levels in young people. Methods: A total of 36 healthy participants aged 18 to 28 years who met the criteria for chronotypes morning type and evening type were analyzed. Analyzes of physical activity level, maximal oxygen uptake, depression, anxiety and stress levels were performed. In all calculations, an alpha of p <0.05 was used for statistical analysis. Results: The level of physical activity was higher in morning types 58% compared to 23.5% of evening types. Women with evening chronotype had lower VO2max levels compared with women with a morning chronotype (p= 0.04). Evening types had higher anxiety levels (p= 0.02) compared to morning types and these data were evidenced in female participants with higher anxiety levels (p=0.03) compared to women with a morning chronotype. Conclusion: Therefore, the study concludes that young people with a evening chronotype exhibited lower levels of physical activity and higher anxiety levels, especially in women.(AU)

Unveiling sleep mysteries: Sleep-wake cycle as a biological parameter of the circadian typology (Chronotype) / Revelando mistérios do sono: Ciclo sono-vigília como parâmetro biológico da tipologia circadiana (cronotipo)

The sleep-wake cycle that is circadian rhythm may have different patterns according to sex, environment and genetics determinants. This chronological cycle type, chronotype, may be populational expressed by the extremes, early or later going to bed and waking up, in a continuum. The first, the Morning-type individuals (the lark) and the later, the Evening types (the owl). Between the two extremes, there is the majority of these chronotypes ­ the intermediate ones. These patterns may be classified according to the questionnaires such as Horne and Ostberg Morningness/ Eveningness Questionnaire (MEQ) and the Munich Chrono Type Questionnaire (MCTQ). The rural population tends to be Morning-type, as well as children and younger women, more than men. The Morning person tends to be more healthy than the Evening ones who are more prone to diseases, as depression and metabolic syndrome. This basic knowledge may be helpful to patient's counseling and management: to avoid mismatch of circadian physiology and social duties / sleep. This circadian desynchrony can increase the risk of diseases, consequently there is a need to chrono-medicine into current treatment strategies.

O ciclo sono-vigília, que é um ritmo circadiano, pode ter padrões diferentes de acordo com os determinantes sexuais, ambientais e genéticos. Esse tipo de ciclo cronológico, cronótipo, pode ser expresso em termos populacionais pelos extremos, indo cedo ou mais tarde para a cama ou saindo dela, em um continuum. O primeiro, os indivíduos do tipo Manhã (a cotovia) e o posterior, os tipos da Tarde (a coruja). Entre os dois extremos, há a maioria desses cronotipos - os intermediários. Esses padrões podem ser classificados de acordo com questionários como o Horne e Ostberg Morningness/Eveningness Questionnaire (MEQ) e o Munich Chrono Type Questionnaire (MCTQ). A população rural tende a ser do tipo matutino, assim como crianças e mulheres mais jovens, mais que os homens.A pessoa da manhã tende a ser mais saudável do que as da noite, mais propensa a doenças, como depressão e síndrome metabólica. Esse conhecimento básico pode ser útil para o aconselhamento e tratamento dos pacientes: para evitar incompatibilidade entre a fisiologia circadiana e os deveres sociais / sono. Essa dessincronia circadiana pode aumentar o risco de doenças, consequentemente, é necessário a cronomedicina nas atuais estratégias de tratamento.

The Effects of Circadian Rhythm Disruption towards Metabolic Stress and Mental Health: A Review (Kesan Gangguan Ritma Sirkadian terhadap Stres Metabolik dan Kesihatan Mental: Satu Tinjauan Kepustakaan / Jurnal Sains Kesihatan Malaysia

@#This review aims to present an overview of current research findings on the possible effects of circadian rhythm (CR) disruption towards metabolic stress and mental health. CR can be described as an internal biological clock that regulates our body functions, based on our sleep/wake cycle. Any time that our normal 24-hour circadian rhythm is altered or interrupted, it will have physiological and psychological impacts. However, in today’s demanding working world, most of us are working defying the normal conditions without realising the significant drawbacks of it. Therefore, this review summarises the findings from several researches on the physiological (metabolic stress) and psychological (cognitive functioning and mental health) impacts of the CR disruption in order to assist people to have a holistic view on the effects of CR to our mind and body. Evidences that linked these aspects to health circumstances of shift workers have also been highlighted.

Analysis of video-electroencephalography in relatively normal very premature infants / 中国新生儿科杂志

Objective To study the video-electroencephalography (vEEG) background activities of very premature infants within the first 7 days after birth.Method The inclusion criteria were gestational age (GA) within 31 weeks and bedside vEEG monitoring within first 7 days of birth.Those with severe cranial ultrasound (CUS) findings,refused treatment,dead and with seizures on vEEG were excluded.The clinical information of included cases were reviewed and the continuity and sleep-wake cycle (SWC) on their EEG background activities were analysed.Result From June 2017 to April 2018,a total of 56 cases were included.Their GA were (29.4 ± 1.6) weeks,and birth weight were (1 306 ± 316) g.A total of 31 cases were diagnosed with asphyxia(1 min Apgar score less than 8),and no one with 5 min Apgar score below 5.Their umbilical artery blood pHs were 7.29 ± 0.07.Their first CUS and the CUS at corrected gestational age (cGA) full term were all within the normal range.The Gesell neurological assessment at cGA 6 months were all within the normal range.As the cGA increased,the continuity of EEG background activities became more continuous as the normal continuous/discontinuous pattern.The 95％ confidence interval of max interburst interval was 95 s.The SWC first occurred at GA 26 w,but was immature,then became mature as the cGA increased.Conclusion The EEG background activity analysis of relatively normal very premature infants within first week shows that interburst interval can be longer than the previous report,and the SWC first appear at GA 26 w.

Effect of Acupuncture at Points in Heel Vessel for Circadian Clock Genes of Period 1 and Period 2 mRNAs in the Suprachiasmatic Nucleus in Insomnia Rats / 针刺研究

OBJECTIVE: To investigate the influence and mechanism of acupuncture at the points in Heel Vessel for the circadian clock genes of Period (Per) 1 and Per 2 mRNAs in the suprachiasmatic nucleus (SCN) in insomnia rats. METHODS: Thirty male SD rats were randomly divided into blank, model, acupuncture groups, 10 rats in each group. Insomnia model was established by intraperitoneal injection of PCPA (suspension, 1 mL/100 g). Acupuncture at "Shenmai" (BL 62) and "Zhaohai" (KI 6) was used in the acupuncture group for continuous 7 days, 15 min/day and once daily. The circadian rhythm was observed; the expressions of Per 1 and Per 2 mRNAs in SCN were examined with real time-PCR. RESULTS: The activity in the model group in rest period everyday increased compared with that in the blank group, and the expressions of Per 1 and Per 2 mRNAs in SCN decreased (P<0.05). Compared with the model group, the activity in the acupuncture group in rest period decreased and the expressions of Per 1 and Per 2 mRNAs in the SCN increased (P<0.05). CONCLUSIONS: Acupuncture at BL 62 and KI 6 can increase the expressions of Per 1 and Per 2 mRNAs in the SCN, so as to decrease the activity in rest period, and improve the quality of sleep in insomnia rats.

Quantitative Analysis of Actigraphy in Sleep Research / 수면정신생리

Since its development in the early 70s, actigraphy has been widely used in sleep research and clinical sleep medicine as an assessment tool of sleep and sleep-wake cycles. The validation and reliability of actigraphic measures have been reasonably examined in healthy normal individuals with good sleep patterns. Recent literature suggests that the use of actigraphy could be further extended to monitor insomnia and circadian sleep-wake disturbances, and detect sleep changes associated with drug treatments and non-pharmacologic interventions, although it is generally recommended to use complementary assessments such as sleep diaries and overnight polysomnography when possible. The development of actigraphy includes its improved hardware sensors for better detection of movements and advanced algorithms to score sleep and wake epochs. In this paper, we briefly review the quantitative analysis methods of actigraphy and its potential applications in sleep research.

Sleep and glycemic control in type 1 diabetes

Objective Our aim in the present study was to elucidate how type 1 diabetes mellitus (T1DM) and sleep parameters interact, which was rarely evaluated up to the moment. Materials and methods Eighteen T1DM subjects without chronic complications, and 9 control subjects, matched for age and BMI, were studied. The following instruments used to evaluate sleep: the Epworth Sleepiness Scale, sleep diaries, actimeters, and polysomnography in a Sleep Lab. Glycemic control in T1DM individuals was evaluated through: A1C, home fingertip glucometer for 10 days (concomitant with the sleep diary and actimeter), and CGM or concomitant with continuous glucose monitoring (during the polysomnography night). Results Comparing with the control group, individuals with diabetes presented more pronounced sleep extension from weekdays to weekends than control subjects (p = 0.0303). Among T1DM, glycemic variability (SD) was positively correlated with sleep latency (r = 0.6525, p = 0.0033); full awakening index and arousal index were positively correlated with A1C (r = 0.6544, p = 0.0081; and r = 0.5680, p = 0.0272, respectively); and mean glycemia values were negatively correlated with sleep quality in T1DM individuals with better glycemic control (mean glycemia < 154 mg/dL). Conclusion Our results support the hypothesis of an interaction between sleep parameters and T1DM, where the glycemic control plays an important role. More studies are needed to unveil the mechanisms behind this interaction, which may allow, in the future, clinicians and educators to consider sleep in the effort of regulating glycemic control. Arch Endocrinol Metab. 2015;59(1):71-8 .

Human Circadian Rhythms / 수면정신생리

A 'circadian rhythm' is a self-sustained biological rhythm (cycle) that repeats itself approximately every 24 hours. Circadian rhythms are generated by an internal clock, or pacemaker, and persist even in the absence of environmental time cues, collectively termed 'zeitgebers.' Although organisms generate circadian rhythms internally, they are entrained by environmental stimuli, particularly the light-dark cycle. Measurement of the endogenous melatonin rhythm provides relatively reliable surrogate way of assessing the timing of the internal circadian clock. Also, core body temperature and cortisol can be used as markers of circadian rhythms. The sleep-wake cycle, body temperature, and melatonin rhythm have a stable internal phase relationship in humans and other diurnal species. They play an important role in controlling daily behavioral rhythms including task performance, blood pressure, and synthesis and secretion of several hormones. In this review, we address not only the properties, methods of measurement, and markers of circadian rhythms, but also the physiological and psychological importance of human circadian rhythms.

Sleep pattern and learning in knockdown mice with reduced cholinergic neurotransmission

Impaired cholinergic neurotransmission can affect memory formation and influence sleep-wake cycles (SWC). In the present study, we describe the SWC in mice with a deficient vesicular acetylcholine transporter (VAChT) system, previously characterized as presenting reduced acetylcholine release and cognitive and behavioral dysfunctions. Continuous, chronic ECoG and EMG recordings were used to evaluate the SWC pattern during light and dark phases in VAChT knockdown heterozygous (VAChT-KDHET, n=7) and wild-type (WT, n=7) mice. SWC were evaluated for sleep efficiency, total amount and mean duration of slow-wave, intermediate and paradoxical sleep, as well as the number of awakenings from sleep. After recording SWC, contextual fear-conditioning tests were used as an acetylcholine-dependent learning paradigm. The results showed that sleep efficiency in VAChT-KDHET animals was similar to that of WT mice, but that the SWC was more fragmented. Fragmentation was characterized by an increase in the number of awakenings, mainly during intermediate sleep. VAChT-KDHET animals performed poorly in the contextual fear-conditioning paradigm (mean freezing time: 34.4±3.1 and 44.5±3.3 s for WT and VAChT-KDHET animals, respectively), which was followed by a 45% reduction in the number of paradoxical sleep episodes after the training session. Taken together, the results show that reduced cholinergic transmission led to sleep fragmentation and learning impairment. We discuss the results on the basis of cholinergic plasticity and its relevance to sleep homeostasis. We suggest that VAChT-KDHET mice could be a useful model to test cholinergic drugs used to treat sleep dysfunction in neurodegenerative disorders.

Sleep habits, daytime sleepiness and sleep quality of high school teachers

The aim of this study was to characterize the sleep-wake cycle, daytime sleepiness and sleep quality of high school teachers. Ninety-eight high school teachers participated in this study. They were asked to complete the Health and Sleep, Horne & Ostberg, Epworth Sleepiness Scale and Pittsburgh Sleep Quality Index questionnaires and to keep a 14-day sleep diary. This study showed that high-school teachers wake up on average 1 h 12 min earlier (ANOVA; p < 0.05) and go to bed on average 34 min earlier (ANOVA; p < 0.05) during the week than on the weekend. This results in an average of 42 min less time in bed (ANOVA; p < 0.05) on weekdays and characterizes partial sleep deprivation. Moreover, 46% and 51% of teachers were diagnosed with excessive daytime sleepiness and poor sleep quality (χ2; p > 0.05), respectively. Therefore, high-school teachers show characteristics of partial sleep deprivation that may contribute to excessive daytime sleepiness and poor sleep quality. This situation may compromise health and quality of life, in addition to teaching performance that can affect the education of their students.

Sleep in Borderline Personality Disorder Individuals / 수면정신생리

Borderline personality disorder (BPD) is characterized by identity and interpersonal problem, affective dysregulation and pervasive severe impulsivity. Although sleep disturbances are not primary symptoms of BPD, they are important aspects of this disorder. However, clinicians and researchers did not give much attention to the sleep symptoms of BPD yet. Measured by nocturnal polysomnography, increased sleep latency as well as reduced total sleep time and sleep efficiency, and 'depression-like' REM abnormalities (i.e., reduced REM latency and increased REM density) are found in BPD patients. Co-morbid sleep disorders such as chronic insomnia, nightmare disorder or circadian rhythm sleep disorder associated with BPD have been reported. Clinicians should focus on the sleep complaints of BPD patients, and carefully manage such symptoms with sleep hygiene education, cognitive psychotherapy or light therapy.

Effect of morning exercise in sunlight on the sleep-wake cycle in adolescents

A delay in bedtime occurs in adolescence compared with childhood. However, the early waking that morning school hours impose leads to partial sleep deprivation. Although exposure to light is the most important regulator of circadian rhythm in mammals, physical exercise influences circadian synchronization. To assess the effect of morning physical exercise in sunlight on the sleep-wake cycle (SWC) in adolescents, 160 first- and second-year high-school students were exposed to classes in their usual classroom (Group C) or in a swimming pool exposed to sunlight (Group E) while physically exercising (EE; i.e., swimming) or resting (EL). At baseline, we applied Health and Sleep and Horne & Ostberg chronotype assessment questionnaires. One week later and during the intervention, we applied the Sleep Diary and Karolinska Sleepiness Scale. During the intervention we observed no changes in bedtime, time in bed and in indices of irregularity of bedtime and wake-up time. The changes observed in wake-up time (i.e., a delay in the EE group on Saturday), sleep quality (i.e., an improvement), and sleepiness (i.e., an increase) were also observed in the control group, discarding an intervention effect. We suggest that morning physical exercise in sunlight had no effect on SWC parameters, sleep quality, or daytime sleepiness, possibly because of the large irregularity in the SWC between weekdays and weekends in adolescent students as well as the low frequency and duration of exercise during the intervention. Therefore, studies that evaluate a higher frequency or duration of exercise are needed to assess its effect on the SWC in adolescents.

Envejecimiento de un reloj (cronobiología de la vejez) / Ageing of a clock (cronobiology of old age)

El envejecimiento es el conjunto de modificaciones morfológicas y fisiológicas generadas como consecuencia de la acción del tiempo sobre los seres vivos. Entre estas modificaciones se debe de incluir la incapacidad de adaptación y de responder a los cambios medioambientales, por cada uno de los órganos, aparatos y sistemas. El envejecimiento de los organismos, y particularmente del hombre, es motivo de preocupación desde hace años debido a que nuestra expectativa de vida ha aumentado significativamente y este hecho ha acrecentado el número de habitantes con problemas de envejecimiento, que presentan procesos de deterioro paulatino de órganos y sus funciones asociadas. Muchas enfermedades, entre ellas ciertos tipos de demencia, enfermedades articulares, cardíacas y algunos tipos de cáncer, han sido asociados al proceso de envejecimiento. Uno de los trastornos más notorios en la senectud es la alteración del ritmo de sueño-vigilia, reflejo de un mal funcionamiento del reloj biológico y en consecuencia del sistema circadiano. En este escrito se abordan las bases fisiológicas de la desincronización interna que sufre el hombre en edad adulta así como sus consecuencias fisiológicas y algunas recomendaciones para coadyuvar al tratamiento de este trastorno.

Aging is the set of morphological and physiological changes generated by the action of time on living beings. These changes include the inability to adapt and respond to environmental challenges, by organs, apparatus and systems. Aging of organisms and particularly of man, has become a concern in recent years, because our life expectancy has increased significantly and this has increased the number of individual ailing from the effects of aging, which includes a series of processes of gradual deterioration of organs and their associated functions. Many diseases, such as dementia, joint disease, cardiovascular disease and some cancers have been associated with the aging process. One of the most notorious disorders in aged people is the alteration of the sleep-wake rhythm, a reflection of a malfunctioning biological clock and thus of the circadian system. This manuscript addresses the physiological basis and consequences of internal desynchronization suffered by aged people and numbers recommendations for the treatment of this disorder.

Correlation of shift work and waist circumference, body mass index, chronotype and depressive symptoms / Correlação entre trabalho de turno e circunferência abdominal, índice de massa corporal, cronotipo e sintomas depressivos

OBJECTIVE: Correlate shift work with body mass index (BMI), waist circumference, chronotype and depressive symptoms. SUBJECTS AND METHODS: This study comprising 14 shift workers and 13 day workers. Subjects were workers from the health area aged 25 to 60 years. Minor psychiatric disorders were accessed by Self Report Questionnaire (SRQ-20) and depressive symptoms by Beck Depression Inventory (BDI). Chronotype was accessed using Morningness-Eveningness Questionnaire (MEQ). Anthropometric measures were taken. RESULTS: Shift workers presented higher BMI (P = 0.03) and waist circumference (P = 0.004) than day workers. Years on shift work were significantly correlated to waist circumference (r = 0.43; P = 0.03) and age (r = 0.47; P = 0.02). Shift work was not correlated with depressive symptoms and chronotype. CONCLUSION: These results may suggest a role played by shift work on the development and/or the early clinic manifestations of metabolic disturbances, becoming a risk factor to metabolic syndrome.

OBJETIVO: Correlacionar o trabalho de turno com índice de massa corporal (IMC), circunferência abdominal, cronotipo e sintomas depressivos. SUJEITOS E MÉTODOS: Amostra de 14 trabalhadores de turno e 13 diurnos, com idade entre 25 e 60 anos. Transtornos psiquiátricos menores foram aferidos pelo Self Report Questionnaire (SRQ-20), sintomas depressivos pelo inventário de Depressão de Beck (BDI) e o cronotipo pelo Morningness-Eveningness Questionnaire (MEQ). As medidas antropométricas foram mensuradas. RESULTADOS: Trabalhadores de turno apresentaram maior IMC (P = 0,03) e circunferência abdominal (P = 0,004) quando comparados aos diurnos. O tempo de trabalho de turno foi correlacionado à circunferência abdominal (r = 0,43; P = 0,03). Não houve correlação entre trabalho e sintomas depressivos e cronotipo. CONCLUSÃO: Os resultados podem sugerir que o trabalho de turno desempenhe um papel no desenvolvimento e/ou nas precoces manifestações clínicas de distúrbios metabólicos, tornando-se um fator de risco para a síndrome metabólica.

Influence of chronotype and social zeitgebers on sleep/wake patterns

Inter-individual differences in the phase of the endogenous circadian rhythms have been established. Individuals with early circadian phase are called morning types; those with late circadian phase are evening types. The Horne and Östberg Morningness-Eveningness Questionnaire (MEQ) is the most frequently used to assess individual chronotype. The distribution of MEQ scores is likely to be biased by several fact, ors, such as gender, age, genetic background, latitude, and social habits. The objective of the present study was to determine the effect of different social synchronizers on the sleep/wake cycle of persons with different chronotypes. Volunteers were selected from a total of 1232 UFPR undergraduate students who completed the MEQ. Thirty-two subjects completed the study, including 8 morning types, 8 evening types and 16 intermediate types. Sleep schedules were recorded by actigraphy for 1 week on two occasions: during the school term and during vacation. Sleep onset and offset times, sleep duration, and mid-sleep time for each chronotype group were compared by the Mann-Whitney U-test separately for school term and vacation. School term and vacation data were compared by the Wilcoxon matched-pair test. Morning types showed earlier sleep times and longer sleep duration compared with evening types (23:00 ± 44 and 508.9 ± 50.27 vs 01:08 ± 61.95 and 456.44 ± 59.08, for the weekdays during vacation). During vacation, the subjects showed later sleep times, except for the morning types, who did not exhibit differences for sleep onset times. The results support the idea that social schedules have an impact on the expression of circadian rhythmicity but this impact depends on the individual chronotype.

Characteristics of sleep-wake cycles in mice lacking prostanoid DP receptors / 中国临床药理学与治疗学

AIM: To investigate the effect of prostanoid DP receptors (DPR) on sleep-wake regulation in mice. METHODS: Under pentobarbital anesthesia, mice were chronically implanted with electroencephalogram (EEG) and electromyogram (EMG) electrodes for polysomnographic recordings. The spontaneous sleep-wake cycles were monitored continuously by EEG/EMG recording system for 24 h beginning at 800 p.m. and analyzed by SLEEPSIGN software in DPR knock out (KO) and wild type (WT) mice. RESULTS: DPR-KO mice exhibited a similar circadian rhythm of sleep-wake cycles to WT mice. The amounts of rapid eye movement (REM) sleep or non-REM (NREM) sleep during both the light and dark periods were identical between the DPR-KO and WT mice. Whereas, an increase in the episode number of wakefulness and a shortage in the duration of NREM sleep were found in DPR-KO mice during the light period compared with WT mice. Moreover, DPR-KO mice showed lower activity in delta-wave component in NREM sleep and higher activity in theta-wave component in REM sleep than WT mice. CONCLUSION: DPR plays a crucial role in mediating the prostaglandin D2-induced sleep. Deficiency of DPR results in the low intensity and fragmented diurnal NREM sleep and the high vigilance REM sleep, with the normal circadian rhythm of sleep in mice.