Validity and Reliability of the Korean Version of Reduced Morningness-Eveningness Questionnaire: Results From a General Population-Based Sample.

BACKGROUND: Chronotype refers to individual variations in diurnal preferences that manifest as everyday behaviors, including sleep patterns. Traditionally, the Horne & Östberg Morningness-Eveningness Questionnaire (MEQ), which comprises of 19 items, has been the standard for determining chronotype. However, its length makes it cumbersome for widespread application. To address this issue, the reduced MEQ (rMEQ), a concise version containing only five items from the MEQ, was developed for a more practical approach to chronotype assessment. This study aimed to evaluate the validity and reliability of Korean version of rMEQ in a sample from the general Korean population. METHODS: The Korean version of the rMEQ comprises of items 1, 7, 10, 18, and 19 of the original MEQ. The validity of the rMEQ was assessed by correlating its scores with those of the MEQ and Munich Chronotype Questionnaire (MCTQ). Its reliability was determined by calculating internal consistency. RESULTS: A total of 3,030 individuals participated in the study, yielding an average rMEQ score of 14.0 ± 3.4. There was a substantial positive correlation between the rMEQ and MEQ scores (r = 0.859, P < 0.001). Furthermore, the rMEQ scores were significantly negatively correlated with the midpoint of sleep on free days corrected for sleep debt as measured by the MCTQ (r = -0.388, P < 0.001), indicating a robust association with chronotype. The internal consistency of rMEQ, measured using Cronbach's alpha, was 0.609. CONCLUSION: This study finds the Korean version of the rMEQ to be a valid and reliable instrument for assessing chronotype in the general population.

Sleep-wake rhythm and its association with lifestyle, health-related quality of life and academic performance among Japanese nursing students: a cross-sectional study.

BACKGROUND: Young adults are likely to have activities and go to bed late at night due to their age-dependent delayed endogenous circadian clock. The purpose of the present study was to clarify sleep-wake rhythm and its association with lifestyle, health-related quality of life, and academic performance among nursing students. METHODS: Self-reported questionnaires were distributed to undergraduate nursing students at six universities in Japan. Sleep-wake rhythm was assessed using the morningness-eveningness questionnaire. A quantitative design using the generalized linear mixed effect model was utilized to identify the factors related to the evening type among female nursing students (n = 447). RESULTS: About 18% of the participants were identified as the evening type. Evening type was associated with living alone, part-time job, and club activity. Sleep duration on weekdays was shorter, meal time duration was the shortest, and the percentages of students who skipped meals and those who gained body weight were higher in the evening type than in the morning type and intermediate type. Mental health-related quality of life was lower in the intermediate type and evening type than in the morning type, while there was no difference in physical health-related quality of life among these groups. The percentages of the nursing students who have experienced absence, tardiness, falling asleep during class, and/or interference with academic achievement were higher in the evening type than in other groups. CONCLUSIONS: The present study has important implications for nursing students' biological characteristics and lifestyle, which are associated with their health-related quality of life and academic performance.

[Interaction of shift work and psychological capital on abnormal glucose and lipid metabolism among natural gas field workers].

Objective: To explore the interaction between shift work and psychological capital on abnormal glucose and lipid metabolism. Methods: A convenient sampling survey of demographics characteristics, shift work and psychological capital was conducted on 1 415 natural gas field workers by questionnaire in October 2018,and their physiological and biochemical indexes were measured according to standard norms. Multivariate logistic regression model was used to analyze the interaction between shift work and psychological capital on abnormal glucose and lipid metabolism. Results: For 1 415 subjectsthe prevalence of abnormal blood glucose was 21.2%, the prevalence of diabetes was 8.3%.The prevalence of abnormal total cholesterol was 40.4%, the prevalence of hypercholesterolemia was 11.3%.The prevalence of abnormal triglyceride was 41.6%, the prevalence of hypertriglyceridemia was 24.7%.The detection rate of Low-density Lipoprotein was 17.3%, the detection rate of Low-density Lipoprotein was 4.0%, and the detection rate of high-density Lipoprotein was 1.3%. Multiple logistic regression model analysis showed that shift work, the low level of self-efficacy and the low level of optimism was positively associated with abnormal blood glucose, respectively (P<0.05). Shift work was positively associated with abnormal triglyceride (P<0.05). However, there was no interaction between shift work, low self-efficacy, low hope, low resilience, and low optimism on abnormal glucose and lipid metabolism. Conclusion: Shift work was a risk factor of abnormal blood glucose and triglyceride, self-efficacy and optimism were protective factors of abnormal blood glucose. There was no multiplicative interaction between shift work and psychological capital on abnormal glucose and lipid metabolism in the study population.

Core circadian clock gene expression in human dental pulp-derived cells in response to L-mimosine, hypoxia and echinomycin.

Core circadian clock genes set the pace for a wide range of physiological functions, including regeneration. The role of these genes and their regulation in the dental pulp, in particular under hypoxic conditions, is unknown. Here we investigated if core clock genes are expressed in human dental pulp-derived cells (DPC) and if their expression is modulated by the hypoxia mimetic agent, L-mimosine (L-MIM), hypoxia or echinomycin. Dental pulp-derived cells in monolayers and spheroids were treated with L-MIM, hypoxia or echinomycin. mRNA levels of the core circadian clock genes were analysed using quantitative PCR (qPCR) and their protein levels were analysed by western blot. All core clock genes and proteins were produced in DPC monolayer and spheroid cultures. The expression of cryptochrome circadian regulators and period circadian regulators was reduced by L-MIM, hypoxia and echinomycin at mRNA, but not at protein levels. Time course experiments indicated that modulations were based on alterations in overall mRNA levels of core circadian clock genes. Our results suggest a potential role of the core circadian clock in the response of dental pulp to hypoxia. Future studies need to consider that regulation of the core circadian clock at mRNA levels might not be paralleled by modulation of protein levels.

Chronobiology of Takotsubo Syndrome and Myocardial Infarction: Analogies and Differences.

Several pathophysiologic factors, not harmful if taken alone, are capable of triggering unfavorable events when presenting together within the same temporal window (chronorisk), and the occurrence of many cardiovascular events is not evenly distributed in time. Both acute myocardial infarction and takotsubo syndrome seem to exhibit a temporal preference in their onset, characterized by variations according to time of day, day of the week, and month of the year, although with both analogies and differences.

Examining the connection between weekend catch-up sleep and depression: Insights from 2017 to 2020 NHANES information.

BACKGROUND: Depression, a prevalent mental disorder, has shown an increasing trend in recent years, imposing a significant burden on health and society. Adequate sleep has been proven to reduce the incidence of depression. This study seeks to explore how Weekend Catch-up Sleep (WCS) is connected with the prevalence of depression in the American population. METHODS: The National Health and Nutrition Examination Survey (NHANES) provides representative data for the U.S. POPULATION: We utilized data from the 2017-2018 and 2019-2020 cycles. Depression was operationally defined as a PHQ-9 score exceeding 10. WCS duration was categorized into five groups: no change in sleep duration (=0 h), decreased sleep duration (<0), short catch-up sleep duration (>0 h, ≤1 h), moderate catch-up sleep duration (>1 h, <2 h), and long catch-up sleep duration (≥2 h). RESULTS: Among the 8039 individuals, the distribution of WCS duration was as follows: no change (WCS = 0 h) in 2999 individuals (37.3 %), decreased sleep (WCS < 0 h) in 1199 individuals (14.9 %), short catch-up sleep (0 h < WCS ≤ 1 h) in 1602 individuals (19.9 %), moderate catch-up sleep (1 h < WCS < 2 h) in 479 individuals (6.0 %), and long catch-up sleep (WCS ≥ 2 h) in 1760 individuals (21.9 %). Acting by adjustment for all covariates in a multiple regression analysis, we discovered that persons with 1 to 2 h of weekend catch-up sleep had a substantially low prevalence of depression concerning those with WCS = 0 (OR 0.22, 95 % CI 0.08-0.59, P = 0.007). CONCLUSION: The prevalence of depression in individuals engaging in weekend catch-up sleep for 1 to 2 h is lower than those who do not catch up on weekends. This discovery on the treatment and prevention of depression provides a new perspective. However, further prospective research and clinical trials are needed for a comprehensive investigation.

Bimodal diurnal preference in undergraduate students is associated with negative health and sleep outcomes.

The bimodal preference is a fourth diurnal preference proposed by re-scoring the Morningness-Eveningness Questionnaire. The present work aimed to describe the prevalence of the bimodal preference in a sample of undergraduate students and to characterize the bimodal type in terms of their health and sleep-related outcomes. A web-based cross-sectional study conducted between September 2018 and March 2021 (convenience sampling method). The sample was composed of undergraduate students who completed an electronic form that included the Morningness and Eveningness Questionnaire, the Pittsburgh Sleep Quality Index, the Self-Compassion Scale, the Epworth Sleepiness Scale, the Hospital Anxiety and Depression Scale, and the World Health Organization Subjective Well-Being Index. The final sample consisted of 615 students (82% female, mean age: 23.4 ± 6.5 years), of whom 108 (18%) had positive bimodality indexes. Bimodal subjects comprised 48 students, 8% of the total sample. Bimodal subjects had poorer subjective sleep quality, more daytime sleepiness, lower subjective well-being, greater anxiety and depression symptoms, and lower self-compassion than morning and/or intermediate types; they did not differ from evening types. The description of bimodal diurnal preference in this population may be of interest for the design of academic policies more in line with the circadian reality of students.

Chronobiology of micturition: putative role of the circadian clock.

PURPOSE: Mammals urinate less frequently during the sleep period than the awake period. This is modulated by a triad of factors, including decreased arousal in the brain, a decreased urine production rate in the kidneys and increased functional bladder capacity during sleep. The circadian clock is genetic transcription-translation feedback machinery. It exists in most organs and cells, termed the peripheral clock, which is orchestrated by the central clock in the suprachiasmatic nucleus of the brain. We discuss the linkage between the day and night change in micturition frequency and the genetic rhythm maintained by the circadian clock system, focusing on the brain, kidney and bladder. MATERIAL AND METHODS: We performed an inclusive review of the literature on the diurnal change in micturition frequency, urine volume, functional bladder capacity and urodynamics in humans and rodents, relating this to recent basic biological findings about the circadian clock. RESULTS: In humans various behavioral studies demonstrated a diurnal functional change in the kidney and bladder. Conversely, patients with nocturnal enuresis and nocturia showed impairment in this triad of factors. Rats and mice, which are nocturnal animals, also have a micturition frequency rhythm that is decreased during the day, which is the sleep phase for them. Mice with a genetically defective circadian clock system show impaired physiological rhythms in the triad of factors. The existence of the circadian clock has been proven in the brain, kidney and bladder, in which thousands of circadian oscillating genes exist. In the kidney they include genes involved in the regulation of water and major electrolytes. In the bladder they include connexin 43, a gene associated with the regulation of bladder capacity. CONCLUSIONS: Recent progress in molecular biology about the circadian clock provides an opportunity to investigate the genetic basis of the micturition rhythm or impairment of the rhythm in nocturnal enuresis and nocturia. If this approach is to be translated clinically, a strategy is to analyze and treat the triad of micturition factors as separate parts of 1 problem. The other way could be to cope with this triad of problems simultaneously, if possible, by treating the circadian physiological rhythm itself. The discoveries reviewed point toward further investigation of the micturition rhythm by basic and translational chronobiology.

Health Professionals' Chronotype Association with Salivary Cortisol and Occupational Stress in Neonatal Intensive Care Units.

Burnout syndrome has been reported among health workers, particularly those working in critical areas, and is considered a significant public health problem. This study aimed to investigate the relationship between chronotype and work-related stress, as measured by salivary cortisol levels and burnout, among health professionals working in neonatal intensive care units. A cross-sectional study was conducted across four public hospitals in Fortaleza, Ceará, Brazil. Two hundred and fifty-six health professionals were administered the brazilian version of the Burnout Characterization Scale, the morningness-eveningness questionnaire, for chronotype, a sociodemographic questionnaire that included lifestyle habits and a salivary cortisol test. The results indicated that morning chronotype workers were significantly associated with the following: advanced age (p < 0.001), female gender (p = 0.032), married status (p = 0.014), and having children (p = 0.030) compared to those with evening and intermediate chronotypes. However, no significant association was found between signs of burnout syndrome and chronotype (p = 0.316). Participants whose work shift did not match their chronotype had significantly higher initial salivary cortisol levels (p = 0.013). The findings suggest that adapting working hours to an individual's biological rhythm can help mitigate potential negative effects on physical and mental health. Thus, it is recommended that professionals' working hours be adjusted accordingly.

Seasonal pattern in elderly hospitalized with acute kidney injury: a retrospective nationwide study in Italy.

PURPOSE: Acute kidney injury (AKI) frequently complicates hospitalization and is associated with in-hospital mortality (IHM). It has been reported a seasonal trend in different clinical conditions. The aim of this study was to evaluate the possible relationship between seasons of the year and IHM in elderly hospitalized patients with AKI. METHODS: We selected all admissions complicated by AKI between 2000 and 2015 recorded in the Italian National Hospital Database. ICD-9-CM code 584.xx identified subjects with age ≥ 65 years and age, sex, comorbidity burden, need of dialysis treatment and IHM were compared in hospitalizations recorded during the four seasons. Moreover, we plotted the AKI observed/expected ratio and percentage of mortality during the study period. RESULTS: We evaluated 759,720 AKI hospitalizations (mean age 80.5 ± 7.8 years, 52.2% males). Patients hospitalized with AKI during winter months had higher age, prevalence of dialysis-dependent AKI, and number of deceased patients. In whole population IHM was higher in winter and lower in summer, while the AKI observed/expected ratio demonstrated two peaks, one in summer and one in winter. Logistic regression analysis demonstrated that parameters such as age, autumn, winter, comorbidity burden were positively associated with IHM. CONCLUSION: We conclude that a seasonality exists in AKI, however, relationship between seasons and AKI could vary depending on the aspects considered. Both autumn and winter months are independent risk factors for IHM in patients with AKI regardless of age, sex and comorbidity burden. On the contrary, summer time reduces the risk of death during hospitalizations with AKI.

Weekend catch-up sleep and depression: results from a nationally representative sample in Korea.

BACKGROUND: There is limited information on the association between weekend catch-up sleep (CUS), which has beneficial effects on health, and depression. This study aimed to investigate the association between CUS and depression in adults. METHODS: We used the data of the Seventh Korea National Health and Nutrition Examination Survey, 2016. Depression was defined as Patient Health Questionnaire-9 score ≥10. We categorized CUS duration as ≤0, 0 < to 1, 1 < to 2, and >2 h. RESULTS: Of 5550 eligible participants, 3286 (54.9%), 1033 (19.5%), 723 (14.7%) and 508 (10.9%) had CUS duration ≤0, 0 < to 1, 1 < to 2, and >2 h, respectively; of these, the prevalence of depression was 7.0%, 4.2%, 2.9%, and 6.0%, respectively. Multivariable regression analyses including covariates revealed that individuals with CUS duration 1 < to 2 h had a significantly decreased risk of depression compared to individuals with CUS duration ≤0 h (odds ratio [OR] = 0.517, 95% CI = 0.309-0.865). Individuals with CUS duration 0 < to 1 h (OR = 0.731, 95% CI = 0.505-1.060) and >2 h (OR = 1.164, 95% CI = 0.718-1.886) showed no significantly different risk of depression. CONCLUSIONS: The risk of depression in individuals with CUS duration 1 < to 2 h was lower than for those with CUS duration ≤0 h. This finding provides a better understanding on the association between CUS and depression; and can be a basis for better management of depression.

Temporal distribution of emergency room visits in patients with migraine and other headaches.

Background: Headache is a leading reason for presentation to the emergency department (ED) with migraine being the most frequently headache. To ensure the adequate staffing of healthcare providers during peak times of headache visits, we analyzed the temporal distribution of emergency department visits in patients presenting with headache and/or migraine.Research design and methods: The authors conducted an ecological study, including all consecutive visits to the ED for headache. Patients were classified according to the IHS Classification. We analyzed circadian, circaseptan and circannual patterns for number of visits, comparing migraine patients with other headache patients.Results: There were 2132 ED visits for headache, including primary headache in 1367 (64.1%) cases; migraine in 963 (45.2%); secondary headache in 404 (18.9%); and unspecified headache in 366 (17.1%). The circadian pattern showed peaks around 11:00-13:00 and 17:00-19:00, with visits during the night shift 45% less frequent (p < 0.001). The circaseptan pattern showed a peak on Monday-Tuesday and a low point on Sunday (p < 0.007). The circannual pattern peaked in March and decreased in June.Conclusions: ED visits for headache showed specific circadian, circaseptan and circannual variations. No differences were found in these patterns when comparing migraine patients to other headache patients.

Adverse events associated with oral administration of melatonin: A critical systematic review of clinical evidence.

While melatonin was once thought of simply as a sleep-inducing hormone, recent research has resulted in development of a deeper understanding of the complex physiological activity of melatonin in the human body. Along with this understanding has come widespread, increasing use of melatonin supplementation, extending beyond its traditional use as a sleep aid into novel fields of application. This increased use often involves off-label and self-prescription, escalating the importance of safety data. In order to examine the current knowledge relating to safety of the exogenous neurohormone, we conducted a comprehensive, critical systematic review of clinical evidence. We examined controlled studies of oral melatonin supplementation in humans when they presented any statistical analysis of adverse events. Of the fifty articles identified, twenty-six found no statistically significant adverse events, while twenty-four articles reported on at least one statistically significant adverse event. Adverse events were generally minor, short-lived and easily managed, with the most commonly reported adverse events relating to fatigue, mood, or psychomotor and neurocognitive performance. A few studies noted adverse events relating to endocrine (e.g. reproductive parameters, glucose metabolism) and cardiovascular (e.g. blood pressure, heart rate) function, which appear to be influenced by dosage, dose timing and potential interactions with antihypertensive drugs. Oral melatonin supplementation in humans has a generally favourable safety profile with some exceptions. Most adverse effects can likely be easily avoided or managed by dosing in accordance with natural circadian rhythms. Further research is required to explore the potential for melatonin to interact with endogenous hormones and pharmaceuticals.

Asociación entre cronotipo y síntomas depresivos: un estudio exploratorio

Introducción: el cronotipo es la predisposición natural de cada individuo a experimentar picos de energía o momentos de descanso en función de su ritmo circadiano. Los individuos pueden tener cronotipos matutinos, vespertinos o intermedios, que pueden tener relación con el desarrollo de depresión. Objetivo: determinar la existencia de asociación entre el cronotipo y la sintomatología depresiva en una muestra de adultos. Metodología: este estudio observacional, descriptivo y exploratorio se realizó en agosto de 2023. Se incluyeron en este estudio adultos de ambos sexos. Se recolectaron datos sociodemográficos, y los participantes respondieron el Morningness-Eveningness Questionnaire de Horne y Östberg para evaluar el cronotipo, y el Patient Health Questionnaire de 2 ítems (PHQ-2) para evaluar los síntomas depresivos. Se utilizaron estadísticas descriptivas para todas las variables. Para la estadística inferencial, se utilizó la prueba de chi-cuadrado con un nivel de confianza del 95 %. Se utilizó odds ratio para cuantificar las relaciones. Resultados: un total de 105 personas participaron en el estudio, de las cuales el 58 % eran mujeres. La edad media de la muestra era de 29,4 ± 11,6 años. El 69 % de la muestra presentaba el cronotipo matutino, mientras que el 31 % presentaba el cronotipo vespertino. Se observó que el 31 % de los participantes puntuaba positivamente para depresión (PHQ-2 ≥ 3). Se encontró una relación entre el cronotipo y los puntos de corte del PHQ-2 (p=0,036). Se halló una OR=2,5 (IC 95%: 1,05-5,95) a favor del cronotipo vespertino para el desarrollo de depresión. Conclusión: casi siete de cada diez participantes tenían un cronotipo matutino, mientras que tres de cada diez dieron positivo en depresión. Los individuos con cronotipos vespertinos son más propensos a desarrollar síntomas depresivos que aquellos con cronotipos matutinos.

Introduction: chronotype is the natural predisposition of each individual to experience peaks of energy or moments of rest according to their circadian rhythm. Individuals may have morning, evening, or intermediate chronotypes that may be related to the development of depression. Objective: to determine the existence of an association between chronotype and depressive symptomatology in a sample of adults. Methodology: this observational, descriptive, and exploratory study was conducted in August 2023. Adults of both sexes were included in this study. Sociodemographic data were collected, and participants answered the Morningness-Eveningness Questionnaire by Horne and Östberg to assess chronotype, and the 2-item Patient Health Questionnaire (PHQ-2) to assess depressive symptoms. Descriptive statistics were used for all the variables. For inferential statistics, the chi-squared test was used with a confidence level of 95 %. Odds ratio was used to quantify the relationships. Results: a total of 105 people participated in the study, 58 % of whom were women. The mean age of the sample was 29.4 ± 11.6 years. Sixty-nine percent of the sample presented the morning chronotype, while 31 % presented the evening chronotype. It was found that 31 % of the participants scored positively for depression (PHQ-2 ≥ 3). A relationship was found between chronotype and PHQ-2 cutoff points (p=0.036). An OR=2.5 (95 % CI 1.05-5.95) was found in favor of the evening chronotype for the development of depression. Conclusion: almost seven out of ten participants had a morning chronotype, whereas three out of ten were positive for depression. Individuals with evening chronotypes are more likely to develop depressive symptoms than those with morning chronotypes.

Asociación entre cronotipo y síntomas depresivos: un estudio exploratorio / Association between chronotype and depressive symptoms: an exploratory study

Introducción: el cronotipo es la predisposición natural de cada individuo a experimentar picos de energía o momentos de descanso en función de su ritmo circadiano. Los individuos pueden tener cronotipos matutinos, vespertinos o intermedios, que pueden tener relación con el desarrollo de depresión. Objetivo: determinar la existencia de asociación entre el cronotipo y la sintomatología depresiva en una muestra de adultos. Metodología: este estudio observacional, descriptivo y exploratorio se realizó en agosto de 2023. Se incluyeron en este estudio adultos de ambos sexos. Se recolectaron datos sociodemográficos, y los participantes respondieron el Morningness-Eveningness Questionnaire de Horne y Östberg para evaluar el cronotipo, y el Patient Health Questionnaire de 2 ítems (PHQ-2) para evaluar los síntomas depresivos. Se utilizaron estadísticas descriptivas para todas las variables. Para la estadística inferencial, se utilizó la prueba de chi-cuadrado con un nivel de confianza del 95 %. Se utilizó odds ratio para cuantificar las relaciones. Resultados: un total de 105 personas participaron en el estudio, de las cuales el 58 % eran mujeres. La edad media de la muestra era de 29,4 ± 11,6 años. El 69 % de la muestra presentaba el cronotipo matutino, mientras que el 31 % presentaba el cronotipo vespertino. Se observó que el 31 % de los participantes puntuaba positivamente para depresión (PHQ-2 ≥ 3). Se encontró una relación entre el cronotipo y los puntos de corte del PHQ-2 (p=0,036). Se halló una OR=2,5 (IC 95%: 1,05-5,95) a favor del cronotipo vespertino para el desarrollo de depresión. Conclusión: casi siete de cada diez participantes tenían un cronotipo matutino, mientras que tres de cada diez dieron positivo en depresión. Los individuos con cronotipos vespertinos son más propensos a desarrollar síntomas depresivos que aquellos con cronotipos matutinos.

Introduction: chronotype is the natural predisposition of each individual to experience peaks of energy or moments of rest according to their circadian rhythm. Individuals may have morning, evening, or intermediate chronotypes that may be related to the development of depression. Objective: to determine the existence of an association between chronotype and depressive symptomatology in a sample of adults. Methodology: this observational, descriptive, and exploratory study was conducted in August 2023. Adults of both sexes were included in this study. Sociodemographic data were collected, and participants answered the Morningness-Eveningness Questionnaire by Horne and Östberg to assess chronotype, and the 2-item Patient Health Questionnaire (PHQ-2) to assess depressive symptoms. Descriptive statistics were used for all the variables. For inferential statistics, the chi-squared test was used with a confidence level of 95 %. Odds ratio was used to quantify the relationships. Results: a total of 105 people participated in the study, 58 % of whom were women. The mean age of the sample was 29.4 ± 11.6 years. Sixty-nine percent of the sample presented the morning chronotype, while 31 % presented the evening chronotype. It was found that 31 % of the participants scored positively for depression (PHQ-2 ≥ 3). A relationship was found between chronotype and PHQ-2 cutoff points (p=0.036). An OR=2.5 (95 % CI 1.05-5.95) was found in favor of the evening chronotype for the development of depression. Conclusion: almost seven out of ten participants had a morning chronotype, whereas three out of ten were positive for depression. Individuals with evening chronotypes are more likely to develop depressive symptoms than those with morning chronotypes.

Women amateur street runners have a higher level of chronotype self- perception than men

Abstract Aim: The aims of the present study were to verify the self-perception level of the chronotype of amateur street runners and to test the association between the chronotype, gender, age, and preferred training time. Methods: A total of 166 amateur street runners were included (♀ = 89, age 38.9 ± 11.2 years; ♂ = 77, age 38.0 ± 9.7 years). The Brazilian version of the Horne & östberg questionnaire was used to assess chronotypes and the preferred training time was determined through a multiple choice question. Based on chronotype definitions that suggest that when free to choose, morning-types (MT) would prefer training in the morning, evening-types (ET) in the evening and neither-types (NT) would not have a predilection for any specific time. The corroboration of this hypothesis was assumed as self-perception level of the chronotypes. Results: Women showed higher self-perception levels of their chronotype compared to men (58.4% vs. 41.6%; χ2 = 4.699; p = 0.030). By chronotypes, MT, NT, and ET self-perception levels were 73.9%, 15.9%, 88.9%, respectively (χ2 = 57.489; p < 0.001). The most observed women circadian typology was MT, while in men it was NT (χ2 = 8.951; p = 0.011). However, there was no significant association between gender and preferred training time (χ2 = 2.654; p = 0.265). Age, female gender and preference to exercise during the day are associated with MT. Conclusion: Women runners showed a greater perception of their circadian traits than men, despite there was no association between gender and preferred training time.

Seasonal variation in the superficial vein thrombosis frequency.

INTRODUCTION: A seasonal variation of venous thromboembolic disease frequency is subject to discussion, and has been recently suggested for superficial vein thrombosis (SVT) in a small retrospective study. Our aim was to search for a seasonal variation of SVT frequency according to the data of larger studies. MATERIALS AND METHODS: We analyzed the data of three French prospective multicenter studies with different designs which have included patients with SVT (STENOX, POST, and STEPH studies). Seasonal variation of SVT frequency was evaluated by comparing the observed seasonal frequency of SVT to a theoretical frequency of 25% for each season. RESULTS: The analysis included 1395 patients and 4.75 seasonal cycles. The difference to a theoretical frequency of 25% was statistically significant in one study (POST, p = 0.044). The higher risk difference was -6.1% (95% CI -11.7­−0.5) in summer in STENOX, +7.1% (95% CI +2.7-+11.5) in winter in POST and 4.2% (95% CI -5.2-+13.7) in spring in STEPH, corresponding to a relative risk of 0.80, 1.40 and 1.20, respectively. CONCLUSIONS: A seasonal variation was found in only one study which has the weakest methodology to warrant completeness. Variation pattern was

É possível verificar relações entre baixa visão e padrões de sono por meio de actigrafia? Relato de caso de uma paratleta / Is it possible to verify relations bet ween low vision and sleep patterns through actigraphy? Case report of a para-athlete

Verificar se a actigrafia permite estabelecer relações entre baixa visão e distúrbios do sono em uma paratleta. Utilizamos questionários, diário do sono e actígrafo durante 30 dias. Mostrou-se indiferente para o perfil circadiano com preferência de treinos vespertinos e má qualidade subjetiva do sono. Periodograma com ritmo circadiano e actograma evidenciando irregularidades nos horários para dormir e acordar aos finais de semana, com períodos de repouso diurno ao longo da semana. Média de sono foi de 06h30m com seis despertares por noite. Verificamos que ambiente, hábitos e rotinas contribuíram para a má qualidade de sono. A actigrafia, quando aliada a outras metodologias, mostrou-se útil para estabelecer relações entre baixa visão, qualidade do sono, prática de exercícios e auto percepção, além de contribuir, neste estudo, para o direcionamento de ações de medidas de higiene do sono, permitindo a promoção de melhorias e ganho em qualidade de vida pessoal e profissional.

Verify if the actigraphy can set relations between low vision and sleep disorders in a para-athlete. Questionnaires, sleep diary and actigraph were used during 30 days. The participant presented an indifferent circadian profile, with preference for evening training and poor subjective sleep quality. Periodogram with circadian rhythm and actogram showing irregularities in the times to sleep and wake up on weekends, with periods of day rest throughout the week. The average sleep time was 06h30m with six awakenings per night. It was found that environment, habits and routines contributed to poor sleep quality. Actigraphy, when combined with other methodologies, proved to be useful for establishing relationships between low vision, sleep quality, exercise and self-perception. In addition to contributing, in this study, to directing sleep hygiene measures, allowing the promotion of improvements and gain in quality of personal and professional life.

Relationship between chronotype and quality of sleep in medical students at the Federal University of Paraiba, Brazil.

OBJECTIVE: The aim of this study was to identify chronotypes of medical students at the Federal University of Paraíba (UFPB) and its relationship to quality of sleep, daytime sleepiness, age, sex and season of birth. METHODS: The final sample consisted of 221 students, assessed by four questionnaires: demographic questionnaire, Morningness-Eveningness Questionnaire (MEQ), Pittsburgh Sleep Quality lndex (PSQI) and Epworth Sleepiness Scale (ESS). RESULTS: There was a statistically significant difference between groups with respect to chronotypes and PSQI score (p<0.0005), but not with excessive daytime sleepiness. A significant negative correlation was found between the scores of MEQ and PSQI (rho=-0.3, p<0.0005), demonstrating that the greater the eveningness, the worse the sleep quality. It was observed that 51.6% of students were classified as indifferent chronotype, 61.5% had poor quality of sleep, while 42.1% had excessive daytime sleepiness. Sex and season at birth did not differ between chronotypes. CONCLUSION: These findings demonstrate that the evening chronotype was associated with poor quality of sleep in medical students, but not with increased daytime sleepiness, with potential impairment to their academic performance and quality of life.

Distribution of Chronotypes among a Sample of Iraqi Kurdish Medical Students.

OBJECTIVES: The aim of this study was to assess the distribution of chronotypes in a sample of Iraqi Kurdish medical students. METHODS: A descriptive cross-sectional study was conducted at the Hawler Medical University College of Medicine in Erbil City, Iraq, between 1(st) January and 31(st) March 2013. A total of 580 students were given the reduced version of the Horne and Ostberg Morningness-Eveningness Questionnaire (MEQr), a close-ended self-administered questionnaire. RESULTS: Of the 580 students, 130 (22.4%) were male and 450 (77.6%) were female. The mean age ± standard deviation was 20.3 ± 1.45 years, with a range of 17-24 years. Most of the students (52.6%) were in the intermediate class, followed by morning type (24.1%) and evening type (23.3%). Significant gender differences were detected in the proportion of morning, intermediate and evening types (P <0.001). The mean scores for the female students were 14.8 ± 2.2 and the mean scores for the male students were 14.6 ± 7.3, with no statistically significant differences (P = 0.45). CONCLUSION: Students in the College of Medicine were mostly classified as intermediate types. The morning type was more common among this student population, particularly male students, than has been reported in similar age groups in some Western countries. There was a significant gender difference in the proportion of MEQr types.