The relationship between chronotype and mental toughness in adolescents: Is resilience a mediator?

OBJECTIVE: This study was designed to examine the mediator role of resilience in the relationship between chronotype and mental toughness in adolescents. METHODS: The descriptive correlational study was completed with 342 high school students from one school in Türkiye (mean age 17.25±1.11 years). Data were collected with the Morningness-Eveningness Scale for Children, Child and Youth Resilience Measure, and Mental Toughness Scale for Adolescents. Hierarchical regression analyses with PROCESS Model 4 were used to evaluate the mediator effect. RESULTS: It was observed that the morning chronotype tendency increased resilience (p < 0.001) mental toughness (p < 0.001). Higher resilience led to increased mental toughness. When the mediation effect was examined, resilience was a full mediator in the relationship between chronotype characteristics and mental toughness (ß=0.396; p = 0.000). CONCLUSIONS: According to these results, a morning chronotype tendency in adolescents increases their resilience and, therefore, mental toughness. These results suggest that effective methods for enhancing mental toughness in adolescents should be multifaceted. Additionally, it highlights the importance of identifying and regulating chronotype tendencies among adolescents, while also emphasizing the need to increase resilience in this demographic.

Association between chronotype, social jetlag, sleep quality, and academic burnout among nursing students: A cross-sectional study.

Academic burnout in nursing students is a serious problem worldwide that results in emotional exhaustion, cynicism and low professional efficacy. The aim of the current study was to examine the association between sleep quality and circadian rhythm indicators and academic burnout among Iranian nursing students. This cross-sectional study was conducted on 325 undergraduate nursing students studying at Qazvin University of Medical Sciences between November and February 2023. Data collection was carried out using self-report questionnaires including demographic characteristics, The Pittsburgh Sleep Quality Index (PSQI), reduced-Morningness-Eveningness Questionnaire (r-MEQ), and the Maslach Burnout Inventory-Student Survey (MBI-SS). Social jetlag (SJL) was defined as the absolute value of the difference between the midpoint of sleep on free days (MSF) and the midpoint of sleep on workdays (MSW). Data were analyzed using univariate and multivariate linear regression models. About 31.4% of participants had evening chronotype and almost half of them suffered from poor sleep quality. About 47.7% of the participants had SJL ≥ 2 h. In the multivariate linear regression model, students with evening chronotype compared to morning chronotype experienced more academic burnout in emotional exhaustion, cynicism and professional efficacy. PSQI score was only correlated with emotional exhaustion and cynicism subscales. Increased SJL was a predictor on all three subscales of academic burnout. The findings suggested that evening chronotype, poor sleep quality, and high SJL were associated with increased likelihood of academic burnout in nursing students. Assessment of circadian preference and sleep quality is beneficial for timely identification and prevention of academic burnout in nursing students.

Index assessment of periodontal status in patients on the background of administering a drug with circadian activity.

OBJECTIVE: Aim: The aim of this study was to determine the effect of application of drug with circadian activity (pioglitazone) for treatment of patients with periodontist. PATIENTS AND METHODS: Materials and Methods: Group I - 18 individuals with healthy periodontium. Group II - 12 participants with stage II, grade B periodontitis treated with a standard treatment protocol. Group III - 12 participants with stage II, grade B periodontitis, treated with a regimen that included the standard protocol along with the administration of pioglitazone prescribed at recommended times of intake. Group IV - 12 participants with stage II, grade B periodontitis treated with the standard protocol and pioglitazone against the recommended intake hours. RESULTS: Results: The Simplified Oral Hygiene Index in Group I was 0.406±0.034. In Group II, it was 2.5±0.06. In Group III, the hygiene index was 2.633±0.056 and in Group IV it was 2.5±0.059. The Papillary-Marginal-Alveolar Index in Group I was 0.033±0.004. In Group II, it was 0.366±0.011. For Group III, the PMA index was 0.38±0.012 and for Group IV it was 0.378±0.01. The Russell's Periodontal Index in Group I was 0.111±0.008. In Group II, it was 4.668±0.155. For Group III - 4.708±0.132 and for Group IV it was 4.575±0.089. The Gingival Bleeding Index (GBI) in Group I was 0.031±0.003, while in Group II, it was 0.266±0.009, in Group III, it was 0.273±0.007 and in Group IV it was 0.278±0.006. CONCLUSION: Conclusions: The administration of pioglitazone (the drug with circadian activity) according to its circadian stage indeed has a positive effect on the periodontal status changes of patients with stage II, grade B periodontitis.

The Relationship Between Big Five Personality Traits and Sleep Patterns: A Systematic Review.

Sleep, an intrinsic aspect of human life, is experienced by individuals differently which may be influenced by personality traits and characteristics. Exploring how these traits influence behaviors and sleep routines could be used to inform more personalized and effective interventions to promote better sleep. Our objective was to summarize the existing literature on the relationship between personality traits and sleep patterns through a systematic review. An abstract and keyword search was conducted in PsycINFO, Cochrane and PubMed, collecting relevant literature, published between January 1980 and June 2024. A total of 1713 records were found, of which 18 studies were analyzed in the descriptive synthesis. Relevant studies covered populations in 11 different countries, Australia, China, Estonia, Finland, Germany, Italy, Japan, Poland, Turkey, the United Kingdom, and the United States, comprising a total of 58,812 subjects. All studies reported an association between a sleep pattern with at least one of the Big Five personality traits (agreeableness, conscientiousness, extraversion, neuroticism, openness to experience). Ten studies found associations between personality and sleep quality, all of which reported a link between neuroticism and sleep quality (effect sizes 0.183-0.40). Five studies found an association between conscientiousness and morningness (effect sizes 0.16-0.35). Other sleep patterns linked to personality traits included sleep duration, nightmare frequency and distress, sleep deficiency, sleep continuity, insomnia severity and sleep problems, sleep hygiene, sleep latency and daytime sleepiness. This novel systematic review confirms that sleep and personality traits are related, suggesting that those traits should be considered when trying to understand or change one's sleep behavior.

Unravelling the ideal roster: A cross-sectional study of nurse shift preferences using multivariate analysis: Unravelling the ideal roster: An analysis of nurse shift preferences.

AIM: Our study aims to explore nurses' shift preferences in relation to their personal characteristics and examine how these preferences align with the rosters imposed in Belgian healthcare settings. Additionally, the study seeks to identify patterns in shift preferences across different days of the week and investigate the existence of distinct groups of nurses with similar preferences, further examining the link between these groups and their personal characteristics. DESIGN: Cross-sectional. METHODS: Questionnaires were distributed to 778 nurses across 11 general hospitals in Belgium, collecting data on demographics, chronotype, shift preferences, and roster alignment. Statistical analyses included logistic regression, principal component analysis, and k-means clustering. RESULTS: Age and chronotype significantly influence nurses' shift preferences. Preferences were consistent across the days within the week. The study revealed two groups of preferences: 'early birds' (preferring morning/day shifts) and 'night owls' (preferring evening/night shifts). Night owls were often neutral or evening-type chronotypes and had a higher alignment between imposed and ideal rosters. CONCLUSIONS: This study reinforces the importance of considering individual differences in nurses' shift preferences, linked to age and chronotype, and advocates for the adoption of flexible, personalized rostering systems. IMPLICATIONS: Personalized scheduling has the potential to improve workforce management, suggesting that healthcare administrators should consider individual preferences in rostering to mitigate the challenges of nurse understaffing. IMPACT: Tackles the pressing problem of nurse understaffing. Proposes that tailored rosters based on individual preferences could improve work conditions for nurses. Relevant to policymakers aiming to enhance nursing workforce management. REPORTING METHOD: STROBE Statement (for cross-sectional studies). PATIENT OR PUBLIC CONTRIBUTION: None.

Pre-COVID-19 short sleep duration and eveningness chronotype are associated with incident suicidal ideation during COVID-19 pandemic in medical students: a retrospective cohort study.

Introduction: Cross-sectional evidence suggests that sleep problems increased the risk of suicide during the 2019 coronavirus disease (COVID-19) pandemic. However, a lack of longitudinal studies examined the relationship between pre-COVID-19 sleep duration, chronotype and incident suicide during the COVID-19 pandemic. Thus, we examined these associations in a longitudinal study of medical students. Methods: From the Shantou College Student Sleep Cohort, a total of 333 first and second grade medical students (age 19.41 ± 0.82 years, female 61.26%), without suicidal ideation (SI) at pre-COVID-19 period, were followed up during the COVID-19 pandemic. Incident SI was defined by their response to the 9th question from the Beck Depression Inventory. Short sleep duration was defined as less than 7 h/night. The Morningness-Eveningness Questionnaire was used to evaluate the participants' chronotype. Logistic regression with adjusted odds ratios (AOR) and 95% confidence intervals (95% CI) was used to examine the association between sleep and SI. Results: The incidence of SI during the COVID-19 pandemic was 5.71%. Logistic regressions with confounding factors adjustment showed that both short sleep duration (AOR = 4.91, 95% CI = 1.16-20.74) and eveningness (AOR = 3.80, 95% CI = 1.08-13.30) in the pre-COVID-19 period were associated with increased risk of incident SI during the COVID-19 pandemic. Conclusion: Pre-COVID-19 short sleep duration and eveningness predict incident SI during the COVID-19 pandemic in medical students. Prolonging sleep duration may help to decrease SI during major public health crises.

Diurnal cognitive functioning in patients with myasthenia gravis with the role of chronotype and depression: a pilot study.

Purpose: Myasthenia gravis (MG) is an autoimmune disease manifested by fatigue and weakness of the skeletal muscles. Recent research has indicated that MG patients perform significantly worse than healthy controls in cognitive domains such as attention, verbal fluency, visual learning, and memory. This study aimed to investigate the diurnal fluctuations in cognitive performance in patients with myasthenia gravis in relation to selected clinical and socioeconomic parameters of the disease course, along with the role of chronotype and depression. Methods: The participants were recruited from a neurology outpatient clinic. Patients' cognitive functions were assessed twice: in the morning and the evening of the same day. Neuropsychological diagnosis included attention, memory, executive, verbal, and visuospatial abilities. Mood was measured with the Beck Depression Inventory-II and Positive and Negative Affect Schedule. The Morningness-Eveningness Questionnaire was used to examine chronotype. Results: The analyses performed showed no significant differences between subjects and within subjects, apart from semantic fluency. Patients receiving antidepressant treatment obtained better results on attention and working memory tasks. Conclusions: The data obtained show that diurnal neuropsychological performance in MG patients is associated with depression. Routine assessment and treatment of mood disorders could significantly improve cognitive functioning in myasthenia gravis patients.

Effects of school start time and its interaction with the solar clock on adolescents' chronotype and sleep: A systematic review and meta-analysis.

Adolescents' late chronotypes colliding with early school start times (SSTs) are associated with students' unhealthy sleep habits. Most studies comparing different SSTs associate later SSTs with longer sleep duration and lower social jetlag. However, the magnitude of the effect varies between studies and the effect of different SSTs on chronotype is not well established. Importantly, although human circadian rhythms are entrained by sunlight, when studying the effect of different SSTs on adolescents' sleep habits usually only the social clock, and not the solar clock, is considered. This meta-analysis investigates whether later SSTs affect adolescents' sleep habits and chronotype and it assesses factors that can modulate this effect, including the relative importance of social and solar clocks. Here, through a database search we identify 37 studies comparing the effect of different SSTs on adolescents' sleep habits and/or chronotype. Random effect meta-analyses showed that later SSTs are associated with later sleep timings and longer sleep duration on weekdays, lower levels of social jetlag, and later chronotypes. Several meta-regressions reveal that the distance between compared SSTs and the interplay between SSTs and the solar clock modulate the effect of different SSTs on sleep timings and duration on weekdays.

Chronotype in relation to shift work: A cohort study among 37,731 female nurses.

Chronotype may affect tolerance for circadian disruption induced by shift work. This study examines the association between chronotype, self-reported sleep timing, shift type preference, and sleep problems among nurses, and studies chronotype stability over time. The study included 37,731 Dutch female nurses who completed a baseline (2011) and follow-up questionnaire (2017), with information on shift work (e.g., job history, shift type preference [collected in 2017 only]), and sleep characteristics (e.g., chronotype, preferred sleep-wake time in a work-free period [collected in 2017 only], and sleep problems between working days according to Medical Outcomes Study-Sleep Problem Index II [MOS-SPI-II]). The association between chronotype and sleep timing was examined using (age-adjusted) linear regression. Associations between chronotype and shift type preference and sleep problems (MOS-SPI-II >30) were examined using ordered logistic and Poisson regression, respectively. With later chronotype, midsleep time increased (definite evening vs. intermediate types [reference]: ß = 55 min, 95% confidence interval [95% CI]: 54-55), the odds ratio (OR) for 1-point increase in preference for night (2.68; 95% CI: 2.48-2.90) and evening shifts increased (OR 2.20; 95% CI: 2.03-2.38), while the odds for day (OR 0.17; 95% CI: 0.16-0.18) and morning shifts (OR 0.22; 95% CI: 0.21-0.24) decreased. Intermediate chronotype was associated with fewer sleep problems (median MOS-SPI-II = 27.2, p < 0.01), compared with definite morning (28.9) and evening types (31.7). This study shows that chronotype is associated with sleep-wake times in a work-free period, shift type preference, and sleep problems in nurses. Future studies on the association of shift work-induced circadian disruption and health outcomes should therefore consider chronotype as effect-modifier.

Association of chronotype with language and episodic memory processing in children: implications for brain structure.

Introduction: Chronotype refers to individual preference in circadian cycles and is associated with psychiatric problems. It is mainly classified into early (those who prefer to be active in the morning and sleep and wake up early) and late (those who prefer to be active in the evening and sleep and wake up late) chronotypes. Although previous research has demonstrated associations between chronotype and cognitive function and brain structure in adults, little is known regarding these associations in children. Here, we aimed to investigate the relationship between chronotype and cognitive function in children. Moreover, based on the significant association between chronotype and specific cognitive functions, we extracted regions-of-interest (ROI) and examined the association between chronotype and ROI volumes. Methods: Data from 4,493 children (mean age of 143.06 months) from the Adolescent Brain Cognitive Development Study were obtained, wherein chronotype (mid-sleep time on free days corrected for sleep debt on school days) was assessed by the Munich Chronotype Questionnaire. Subsequently, the associations between chronotype, cognitive function, and ROI volumes were evaluated using linear mixed-effects models. Results: Behaviorally, chronotype was negatively associated with vocabulary knowledge, reading skills, and episodic memory performance. Based on these associations, the ROI analysis focused on language-related and episodic memory-related areas revealed a negative association between chronotype and left precentral gyrus and right posterior cingulate cortex volumes. Furthermore, the precentral gyrus volume was positively associated with vocabulary knowledge and reading skills, while the posterior cingulate cortex volume was positively associated with episodic memory performance. Discussion: These results suggest that children with late chronotype have lower language comprehension and episodic memory and smaller brain volumes in the left precentral gyrus and right posterior cingulate cortex associated with these cognitive functions.

Sleep Quality, but Not Personality Traits, Mediates the Relationship between Chronotype and Life Satisfaction: A Study in Young Adults.

Chronotype reflects the morningness-eveningness preference over a 24 h period. Significant data indicate meaningful differences between evening types (ETs) and morning types (MTs) in behavior, personality traits, health, and well-being. This study explores the interactions between chronotype, sleep, personality, and life satisfaction among 254 undergraduate college students (mean age 23.79 ± 1.85). Using online questionnaires, the participants provided demographic information and completed assessments, including the Morningness-Eveningness Questionnaire (MEQ), the Pittsburg Sleep Quality Index (PSQI), a shortened version of the Big Five Inventory (BFI-10), and a life satisfaction uniscale measure. The results revealed a significant association between chronotype and both life satisfaction and sleep quality, where ETs exhibited poorer outcomes compared to MTs. Additionally, the chronotype correlated with agreeableness and conscientiousness, with later chronotypes linked to reduced scores in these personality traits. A key finding in this study was revealed in a mediation analysis in which sleep quality was found to mediate the relationship between chronotype and life satisfaction. The mediation analysis highlighted sleep quality as a crucial process connecting chronotype to life satisfaction. The findings emphasize the importance of addressing sleep quality in interventions aimed at enhancing life satisfaction and overall well-being among ETs. Overall, our results provide valuable insights into the intricate relationships between chronotype, personality, sleep quality, and subjective well-being.

Social Jetlag on Obesity-Related Outcomes in Spanish Adolescents: Cross-Sectional Evidence from the EHDLA Study.

PURPOSE: This study aimed to investigate the association between social jetlag (SJL) and obesity-related outcomes among adolescents from Valle de Ricote (Region of Murcia, Spain). We explored the relationship between SJL and body mass index (BMI) z-score, waist circumference, and body fat percentage, as well as the odds of having excess weight, obesity, and abdominal obesity in a sample of Spanish adolescents. METHODS: A cross-sectional study was conducted using data from the Eating Healthy and Daily Life Activities (EHDLA) project, which included 847 Spanish adolescents aged 12-17 years. SJL was assessed based on the differences in sleep patterns between weekdays and weekends. Obesity-related indicators such as BMI z-score, waist circumference, body fat percentage, excess weight, obesity, and abdominal obesity were measured. Generalized linear models with a Gaussian or binomial distribution were used to analyze the associations between SJL and obesity-related outcomes, adjusting for potential confounders. RESULTS: The analysis revealed significant associations between SJL and BMI z-score (unstandardized beta coefficient [B] = 0.15, 95% CI: 0.05 to 0.25, p = 0.003), waist circumference (B = 1.03, 95% CI: 0.39 to 1.67, p = 0.002), and body fat percentage (B = 0.83, 95% CI: 0.31 to 1.43, p = 0.008). Additionally, the odds ratios (ORs) for excess weight (OR = 1.35, 95% CI: 1.16 to 1.57; p < 0.001), obesity (OR = 1.59, 95% CI: 1.26 to 2.00; p < 0.001), and abdominal obesity (OR = 1.46, 95% CI: 1.23 to 1.72; p < 0.001) increased significantly with each 60 min increment in SJL. CONCLUSIONS: This study pointed out that the misalignment of sleeping times during weekdays and weekends (SJL) is significantly associated with higher BMI z-scores, waist circumference, body fat percentage, and higher odds of excess weight, obesity, and abdominal obesity among adolescents, being more significant in boys than in girls. These findings highlight the importance of addressing circadian misalignment in the prevention and management of obesity and its related metabolic disorders in this population.

Exploring the nexus between sleep, chronotype, and non-cognitive predictors in university students: Implications for academic success.

While the association between sleep-related variables and academic achievement is widely acknowledged, limited attention has been directed towards exploring non-cognitive predictors of academic achievement such as conscientiousness and self-regulation. In this study, we investigated the relationships between various sleep-related factors (circadian preference, chronotype, sleep duration, quality, and irregularity) and non-cognitive predictors (conscientiousness, self-regulation, self-efficacy, and achievement motivation) in 637 university students. Bivariate analyses revealed moderate to strong correlations among several sleep-related measures. Notably, distinctness, representing the subjective perception of daily changes, and daytime sleepiness exhibited negative associations with self-regulation, while high sleep quality was positively linked to robust self-regulation. These findings emphasize the importance of exploring various measures, particularly distinctness within circadian typology. Furthermore, we discuss the potential integration of sleep intervention programs with strategies aimed at enhancing self-regulation.

Bipolar disorder is characterized by chronotype instability: A longitudinal investigation of circadian typology and mood.

BACKGROUND: Chronotype is associated with circadian rhythmicity, a core etiological factor underlying bipolar disorder (BD). Given converging evidence linking late chronotype with poor mental health, the goal of the present study was to examine chronotype (in)stability and its relation to mood symptoms over time. METHODS: Participants with BD I (n = 271), BD II (n = 88), and healthy controls (n = 217) were included (follow-upM=10 years, Range=5-15) from the Prechter Longitudinal Study. Chronotype category and midpoint of sleep, corrected for weekend sleep-debt (MSFsc), were measured with the Munich Chronotype Questionnaire administered every 12 months alongside clinician-rated mood and medication usage. Self-reported mood was measured bi-monthly. Mixed effects models tested whether mood was associated with (in)stability of chronotype category and MSFsc covarying for age, sex, age, and medication. RESULTS: Compared to HC, individuals with BD self-reported having a later chronotype that significantly fluctuated over time. Individuals with BDI showed significantly less stability in MSFsc than HC. Anticonvulsant use was associated with more stability in MSFsc whereas antidepressant use was associated with less stability in MSFsc. CONCLUSIONS: In a large longitudinal cohort, individuals with BD displayed significant instability in circadian typology. Psychopharmacology in BD may have differential impacts on circadian timing that is important to monitor.

Association of chronotype and timing of interferon injection with severity of IFNß-induced flu-like syndrome in Multiple sclerosis (MS) patients.

BACKGROUND: Although Interferon-beta (IFNß) has long been approved as a disease-modifying therapy (DMT) for Multiple sclerosis (MS), flu-like syndrome (FLS) persists as a common adverse effect of interferon therapy. Given the importance of circadian rhythm in regulating physiological processes, we aimed to assess the relationship between patient's chronotype and time of interferon injection with FLS score in MS patients receiving IFNß. METHODS: A cross-sectional study was conducted on 118 MS patients who were referred to the clinic of neurology of Zanjan Vali-e-Asr Hospital for interferon injection. The included were invited to complete a morningness-eveningness questionnaire (MEQ) assessing patients' chronotype. The following data were extracted from patients' record: age, gender, duration of interferon treatment, type of interferon taken, time of interferon injection (morning/evening), FLS score, MS subtype, and usage of pain killers. All data found were imported and statistically analyzed in SPSS ver.26. RESULTS: According to the patients' record, 114 (96.6%) patients had experienced post-interferon injection FLS with different severities. Statistical analysis revealed no significant relationship between the patient's chronotype and FLS score. Nevertheless, the FLS score was significantly higher in those who had evening injections. CONCLUSIONS: Time of interferon injection was significantly associated with FLS score, with higher FLS score following evening injection. However, no significant relationship was found between the FLS score and the patient's chronotype. It is recommended that further studies assessing circadian rhythm using laboratory tests such as melatonin measurement need to be undertaken to investigate the association of circadian rhythm with post-interferon injection FLS.

Subclinical hypomanic experiences in young adults after sleep deprivation are independent of depressive disorders, chronotype or 5-HTTLPR polymorphism.

INTRODUCTION: The acute antidepressant effect of sleep deprivation (SD) in patients with depressive disorders has been studied for more than 60 years. However, hypomanic mood swings after partial or total SD have also been described in people without diagnosed mental disorders. Studying this phenomenon in the general population may yield insights about the mechanisms of therapeutic SD, mania and bipolar disorders. METHODS: A cross-sectional sample of young adults was recruited and classified into those who described having regularly occurring subclinical hypomanic experiences (ROHE) after SD and those who did not. History of psychiatric and physical illness, with screening for depression and mania, as well as alcohol or drug consumption, family history of depressive disorders or suicide, 5-HTTLPR polymorphism, and MEQ-SA chronotype were collected. RESULTS: A total of 251 participants were included; 39.0% indicated regularly having subclinical hypomanic experiences after SD. These experiences were not associated with depressive or mania screening, history of psychiatric illness, family history, 5-HTTLPR polymorphism, or MEQ-SA chronotype. CONCLUSIONS: ROHE after non-therapeutic SD seem to be a relatively common phenomenon in young adults, independent of depressive mood state. Our results suggest that therapeutic SD may depend on a physiological phenomenon of subclinical affective disturbance after SD that affects a part of the general population, independent of psychiatric diagnosis. Further studies could elucidate associated factors and contribute to our understanding of (hypo-)manic mood states.

Lifetime prevalence and characteristics of sleep paralysis in Italian university students population.

Sleep paralysis (SP) is a REM-related parasomnia, characterized by the inability to perform voluntary movements. It is a relatively widespread phenomenon in the general population and, although usually not dangerous, it is experienced with intense fear. The current study aims to evaluate the lifetime prevalence and characteristics of SP in the Italian student population. The study was conducted online, through an online battery of questionnaires. We used the Unusual Sleep Experience Questionnaire to investigate the prevalence of the disorder and the typical characteristics, metacognitive beliefs on the episodes, and previous distress factors. We also collected information about anxiety and depression symptomatology, sleep quality, and circadian preferences. Four hundred and thirty-two participants (333 F, 22.8 ± 2.57 y) took part in the study and 37.5 % of them reported having experienced at least one SP episode in their lifetime. On a physiological level, the most common features were the inability to speak followed by a tingling sensation and the inability to open the eyes, consistent with REM muscle atonia. Cognitive features during episodes include the perception of a presence in the room, followed by the fear of dying. Participants who reported SP had higher anxiety and worse sleep quality, and were more associated with evening chronotypes compared to non-SP responders. Our results show that SP is generally widespread in Italian students, in line with the prevalence reported in previous studies. Further studies could investigate the effects of suggested therapies to decrease the number of episodes of the disorder, especially in those who experience it recurrently.

Depression and suicidal ideation among Chinese college students during the COVID-19 pandemic: the mediating roles of chronotype and sleep quality.

BACKGROUND: This study was intended to investigate the correlation between depression and suicidal ideation among Chinese college students during the COVID-19 pandemic and the potential mediating roles of chronotype and sleep quality in this relationship . METHODS: A sample of 4,768 college students was selected from four institutions in Anhui Province, China, and the study was conducted during the COVID-19 pandemic (November to December 2020) using a stratified, cluster, multi-stage sampling method. This study used the two-item Patient Health Questionnaire (PHQ-2) to assess depressive symptoms, the Morningness-Eveningness Questionnaire 19 (MEQ-19) to determine individual sleep chronotypes (i.e., morning or evening preference), and the Pittsburgh Sleep Quality Index (PSQI) to evaluate sleep quality. Participants were asked about suicidal ideation. MPLUS 8.3 software was used to analyze the mediating effect of chronotype and sleep quality on the relationship between depression and suicidal ideation. RESULTS: During the COVID-19 pandemic, the prevalence of suicidal ideation among Chinese college students was 5.4%. Depression was inversely correlated with chronotype (beta = - 0.346, P < 0.01) and positively correlated with sleep quality (beta = 0.846, P < 0.001), indicating that students experiencing depressive symptoms were more likely to have a later chronotype and poor sleep quality. A later chronotype (beta = - 0.019, P < 0.05) and poor sleep quality (beta = 0.066, P < 0.01) predicted suicidal ideation. Depression emerged as a direct and significant risk factor for suicidal ideation (effect value = 0.535, 95% confidence interval: 0.449 ~ 0.622). Chronotype and sleep quality were found to have potential mediating effects on the relationship between depression and suicidal ideation; however, the chain-mediating effect of chronotype and sleep quality was not statistically significant. CONCLUSIONS: Our findings suggest that during the COVID-19 pandemic, depression can precipitate suicidal ideation through its influence on sleep chronotype and quality. These compelling findings highlight the urgency of early intervention strategies intended to mitigate suicidal thoughts, particularly among students exhibiting depressive symptoms, who experience disrupted sleep patterns and poor sleep quality.

Time-restricted eating, the clock ticking behind the scenes.

Introduction: Maintaining metabolic balance relies on accumulating nutrients during feeding periods and their subsequent release during fasting. In obesity and metabolic disorders, strategies aimed at reducing food intake while simulating fasting have garnered significant attention for weight loss. Caloric restriction (CR) diets and intermittent fasting (IF) interventions have emerged as effective approaches to improving cardiometabolic health. Although the comparative metabolic benefits of CR versus IF remain inconclusive, this review focuses on various forms of IF, particularly time-restricted eating (TRE). Methods: This study employs a narrative review methodology, systematically collecting, synthesizing, and interpreting the existing literature on TRE and its metabolic effects. A comprehensive and unbiased search of relevant databases was conducted to identify pertinent studies, including pre-clinical animal studies and clinical trials in humans. Keywords such as "Obesity," "Intermittent Fasting," "Time-restricted eating," "Chronotype," and "Circadian rhythms" guided the search. The selected studies were critically appraised based on predefined inclusion and exclusion criteria, allowing for a thorough exploration and synthesis of current knowledge. Results: This article synthesizes pre-clinical and clinical studies on TRE and its metabolic effects, providing a comprehensive overview of the current knowledge and identifying gaps for future research. It explores the metabolic outcomes of recent clinical trials employing different TRE protocols in individuals with overweight, obesity, or type II diabetes, emphasizing the significance of individual chronotype, which is often overlooked in practice. In contrast to human studies, animal models underscore the role of the circadian clock in mitigating metabolic disturbances induced by obesity through time-restricted feeding (TRF) interventions. Consequently, we examine pre-clinical evidence supporting the interplay between the circadian clock and TRF interventions. Additionally, we provide insights into the role of the microbiota, which TRE can modulate and its influence on circadian rhythms.