Validation of the Munich Chronotype Questionnaire (MCTQ) in Chinese college freshmen based on questionnaires and actigraphy

Validation of the French version of the Munich ChronoType questionnaire and associations between chronotype and physiological parameters

Assessing chronotype is essential in clinical and research environments, but the Munich ChronoType Questionnaire (MCTQ), a widely utilised tool, is not available in French. Therefore, we carried out an observational monocentric study to validate the French MCTQ against the sleep diary for sleep schedules, the Morningness-Eveningness Questionnaire (MEQ) for chronotype, and polysomnography measures. We utilised the mid-sleep point on free days (MSF), adjusted for sleep debt (MSFsc), to gauge morningness/eveningness. The study included 80 participants (average age: 40.9 years, 50% female). The sleep schedules determined by the MCTQ and the sleep diary showed a high correlation. The MSFsc demonstrated a significant correlation with the MEQ, persisting even under sleep constraints such as an alarm on free days. The predictive accuracy was strong for a morning chronotype and moderate for an evening chronotype as assessed using the MEQ. In summary, the French MCTQ is a reliable tool for researchers and clinicians for assessing sleep schedules and chronotype in French-speaking populations. The MSFsc can effectively predict chronotype, even under sleep constraints. However, for the evening chronotype, self-assessment appears to be more accurate. The association with polysomnography measures enriches our understanding of the chronotype at the intersection of behaviour and physiology.

Construct validity and test-retest reliability of a chrononutrition questionnaire for shift work and non-shift work populations

The irregular eating patterns of both shift workers and evening chronotypes adversely affect cardiometabolic health. A tool that conveniently captures temporal patterns of eating alongside an indicator of circadian rhythm such as chronotype will enable researchers to explore relationships with diverse health outcome measures. We aimed to investigate the test-retest reliability and convergent validity of a Chrononutrition Questionnaire (CNQ) that captures temporal patterns of eating and chronotype in the general population (non-shift workers, university students, retirees, unemployed individuals) and shift work population. Participants attended two face-to-face/virtual sessions and completed the CNQ and food/sleep/work diaries. Outcomes included subjective chronotype, wake/sleep/mid-sleep time, sleep duration, meal/snack regularity, meal/snack/total frequency, times of first/last/largest eating occasions (EO), main meal (MM) 1/2/3, and duration of eating window (DEW). 116 participants enrolled (44.5 ± 16.5 years, BMI: 27.3 ± 5.8 kg/m2, 73% female, 52% general population); 105 completed the study. Reliability was acceptable for chronotype, sleep, and all temporal eating patterns except on night shifts. Convergent validity was good for chronotype and sleep except for certain shift/shift-free days. Generally, meal/snack regularity and frequency, and times of first/last EO showed good validity for the general population but not shift workers. Validity was good for DEW (except work-free days and afternoon shifts) and times of MM 1/2/3 (except afternoon and night shifts), while time of largest EO had poor validity. The CNQ has good test-retest reliability and acceptable convergent validity for the general and shift work population, although it will benefit from further validation, especially regarding regularity, frequency, and times of first and last eating occasions across more days amongst a larger sample size of shift workers. Use of the CNQ by researchers will expand our current understanding of chrononutrition as relationships between timing of food intake and the multitude of health outcomes are examined.

Sleep and daytime functioning in children with tourette syndrome: A two-week case-control study with actigraphy and cognitive assessments

There is increasing recognition of the high prevalence of sleep issues in children with Tourette syndrome (TS), a condition characterised by motor and vocal tics. Overnight polysomnography (PSG) has been the primary mode of sleep assessment in the TS literature, despite the extensive use of actigraphy in other neurodevelopmental populations. As a result, there are existing research gaps surrounding day-to-day variability of sleep in TS and links to daytime functioning. This study adopts a naturalistic, intensive longitudinal design to examine sleep in children with TS while considering potential links to tic severity and daytime functioning. Participants were 34 children aged between 8 and 12 years (12 with TS, 22 neurotypical controls). Wrist actigraphs tracked sleep-wake cycles across two weeks and a battery of scales and cognitive assessments measured sleep disturbances and daytime functioning. Mixed models using N = 476 nights of actigraphy data found that relative to controls, children with TS had significantly increased time in bed, increased sleep onset latency, reduced sleep efficiency, lower subjective sleep quality, but comparable actual sleep time. Higher self-report tic severity at bedtime did not predict increased sleep onset latency. In the sleep disturbance scale, 83.33 % of children with TS met the clinical cut-off for a sleep disorder. Parent-report emotional, behavioural, and executive difficulties were greater in the TS group relative to controls, but performance on cognitive tasks was comparable between groups. Together, findings highlight sleep disturbances as an important clinical factor to consider in the management of TS, though further research is required to substantiate findings in larger-scale studies. This study demonstrates the feasibility of assessing sleep via actigraphy in children with TS, supporting more widespread use in the future.

Effects of sleep-corrected social jetlag on measures of mental health, cognitive ability, and brain functional connectivity in early adolescence

Approximately half of adolescents encounter a mismatch between their sleep patterns on school days and free days, also referred to as "social jetlag." This condition has been linked to various adverse outcomes, such as poor sleep, cognitive deficits, and mental disorders. However, prior research was unsuccessful in accounting for other variables that are correlated with social jetlag, including sleep duration and quality. To address this limitation, we applied a propensity score matching method on a sample of 6335 11-12-year-olds from the 2-year follow-up (FL2) data of the Adolescent Brain Cognitive Development study. We identified 2424 pairs of participants with high sleep-corrected social jetlag (SJLsc, over 1 hour) and low SJLsc (<= 1 hour) at FL2 (1728 pairs have neuroimaging data), as well as 1626 pairs at 3-year follow-up (FL3), after matching based on 11 covariates including socioeconomic status, demographics, and sleep duration and quality. Our results showed that high SJLsc, as measured by the Munich Chronotype Questionnaire, was linked to reduced crystallized intelligence (CI), lower school performance-grades, and decreased functional connectivity between cortical networks and subcortical regions, specifically between cingulo-opercular network and right hippocampus. Further mediation and longitudinal mediation analyses revealed that this connection mediated the associations between SJLsc and CI at FL2, and between SJLsc and grades at both FL2 and FL3. We validated these findings by replicating these results using objective SJLsc measurements obtained via Fitbit watches. Overall, our study highlights the negative association between social jetlag and CI during early adolescence.

The effect of sleep-corrected social jetlag on crystalized intelligence, school performance, and functional connectome in early adolescence

Approximately half of adolescents encounter a mismatch between their sleep patterns on school days and free days, also referred to as "social jetlag". This condition has been linked to various adverse outcomes, such as poor sleep, cognitive deficits, and mental disorders. However, prior research was unsuccessful in accounting for other variables that are correlated with social jetlag, including sleep duration and quality. To address this limitation, we applied a propensity score matching method on a sample of 8853 11-12-year-olds from the two-year follow-up (FL2) data of the Adolescent Brain Cognitive Development (ABCD) study. We identified 3366 pairs of participants with high sleep-corrected social jetlag (SJLsc, over 1 hour) and low SJLsc (<= 1 hour) at FL2, as well as 1277 pairs at three-year follow-up (FL3), after matching based on 11 covariates including socioeconomic status, demographics, and sleep duration and quality. Our results showed that high SJLsc, as measured by the Munich Chronotype Questionnaire, was linked to reduced crystallized intelligence, lower school performance - grades, and decreased functional connectivity between cortical networks and subcortical regions, specifically between cingulo-opercular network and right hippocampus (cerc-hprh). Further mediation and longitudinal mediation analyses revealed that cerc-hprh connection mediated the associations between SJLsc and crystallized intelligence at FL2, and between SJLsc and grades at both FL2 and FL3. We validated these findings by replicating these results using objective SJLsc measurements obtained via Fitbit watches. Overall, our study highlights the negative association between social jetlag and crystallized intelligence during early adolescence.