Chronobiology International最新文献

Depression is a severe public health problem with high prevalence among university students. Lifestyle behaviors are modifiable and shorten eating duration may help improve mental health. The aim of the study is to analyze the association between longer eating duration and depressive symptoms in a cohort of university students. This longitudinal study evaluated 672 students who entered a public university in Brazil. Food consumption was assessed by 24 hR. Students were classified into terciles according to distribution of daily eating duration. The Patient Health Questionnaire-9 assessed depressive symptoms at a cutoff point ≥10. The associations were estimated by generalized linear models for repeated measures. The adjusted analysis identified that, among women, the third tertile of daily eating duration was associated with a higher risk of depressive symptoms (RR = 1.99, 95% CI = 1.23, 3.21), compared to the second tertile, after 2 y of follow-up. Among male students, there was no association between eating duration and depressive symptoms throughout the follow-up. In conclusion, eating duration in the third tertile, greater than 14 h, was associated with a higher risk of depressive symptoms among female university students.

Previous studies have shown a circadian disadvantage in evening games in professional sports teams traveling westward. This effect has been in part attributed to the circadian misalignment between the traveling team and the local team. Compared to the National Football League (NFL) teams, Canadian Football League (CFL) teams often travel longer distances and play at later times. As such, the objective of the present study was to investigate the circadian disadvantage in the CFL. Data from 8 years of CFL regular season games were extracted from online databases (2014-2021). Wins, score differentials, first downs, average total, passing, penalty, kickoff yards, pass completion percentages, interceptions, fumbles, sacks, and time of possession were extracted for both the offense (made) and defense (allowed) for every away evening game (after 18:00 h; n = 387), with the direction of travel (eastward, same time-zone, westward). One-way ANOVAs Direction of Travel (eastward, same time-zone, westward) on each performance variable were computed to study the circadian effect. Linear regression analyses were done to investigate the effect of the distance traveled by the away team (longitude traveled) on each variable. Significant effects of the direction of travel were found for team variables: score differentials and time of possession. Significant results were also found for both offensive variables: first downs, average kickoff return yards, fumbles; and defensive variables: first downs allowed, average yards per play, average passing yards allowed, average kickoff yards allowed. Post hoc t-tests revealed a circadian disadvantage to teams traveling westward and a circadian advantage for teams traveling eastward. Regression analyses confirmed that performance worsens as distance increases when traveling from east to west and improved when traveling from west to east. These results are consistent with previous findings showing that evening games in some professional sports present important challenges for teams traveling westward. However, there is also an advantage for teams traveling east, suggesting that for CFL players, travel fatigue may have less of an impact than the circadian alignment advantage of traveling eastward. In addition, our results highlight that circadian advantages and disadvantages should be considered not only in relation to teams, but also at an individual level with regard to each player's performance.

Chronotype influences sleep-wake patterns and may affect cognitive and physical functioning in older adults, yet evidence in active ageing populations remains limited. This cross-sectional study included 151 older adults (114 women, 37 men; mean age 70.6 ± 5.80, SD), enrolled in the University of Oviedo's Programme for Senior Students. Chronotype was assessed using the Morningness-Eveningness Questionnaire (MEQ), sleep quality with the Pittsburgh Sleep Quality Index (PSQI), cognitive performance with the Eurotest, and mobility with the Tinetti Mobility Test. Lifestyle factors, including physical activity, nocturnal light exposure, and sleep medication use, were recorded. Associations were analysed using correlation and multivariate regression models. Morning types represented 49.7% of the sample and intermediate types 43%. Higher MEQ scores were positively associated with better mobility (r = 0.20, p < 0.05), and evening types showed lower balance scores than morning/intermediate types (p < 0.05). Women reported poorer sleep than men (PSQI: 8.0 ± 4.01 vs. 5.7 ± 3.54; p < 0.01). Sleep medication use was associated with poorer sleep quality (B = 4.42, 95% CI [3.29, 5.55], p < 0.01) and lower cognitive performance (B = -0.91, 95% CI [-1.71, -0.10], p < 0.05). In this active older cohort, chronotype and sleep-related behaviours were linked to functional outcomes. Morningness was associated with better balance and mobility, whereas sleep medication use and nocturnal light exposure were related to poorer sleep and cognitive performance. These findings underscore the relevance of chronobiological and lifestyle factors in supporting healthy ageing and functional independence.

The relationship between psychological stress and sleep quality is essential for mental health. While self-reported questionnaires are commonly used in epidemiological studies, wearable devices have been increasingly utilized to obtain objective sleep data. This study examined whether daily subjective psychological stress is associated with objectively measured sleep stages in naturalistic (real-world) conditions using wearable devices. We conducted a secondary analysis of a 90-day randomized controlled trial recruited full-time workers with metabolic syndrome (Mets) or high risk of Mets from five Tokyo-based companies. Participants (mean age 43 y; 93% men) used the Fitbit Versa for sleep structure and a dedicated smartphone application for daily questionnaires. Daily psychological stress was assessed using a binary question. Mixed-effects multi-level regression models were used to examine associations between stress and time spent in REM and NREM sleep, respectively. Within-individual psychological stress was positively associated with REM minutes (β: 4.7; 95% CI 2.9, 6.4) and NREM minutes (β: 17.8; 95% CI 13.8, 21.9) in adjusted models. This result suggests that daily individual-level data may be essential for sleep health recommendations. Further research using wearable devices is needed to investigate the possibility of individually optimized interventions targeting psychological stress and its impact on sleep stages.

Depression is highly prevalent and increasingly linked to circadian functioning and self-regulation. Yet little is known about how specific behaviors, such as procrastination, interact with chronotype dimensions to influence vulnerability to depressive symptoms. This study examined whether procrastination moderates associations between multidimensional chronotype and depressive symptoms in a large adult sample (N = 3606, aged 20-60). Participants completed self-report measures of chronotype, depressive symptoms, procrastination, and conscientiousness. Chronotype was assessed across three dimensions: Morning Affect (MA), Eveningness (EV), and Distinctness (DI). Results showed that lower MA and higher DI - reflecting greater daily energy fluctuations - were strong predictors of depressive symptoms. Procrastination significantly moderated these relationships by increasing overall levels of depressive symptoms: the protective effect of MA weakened at higher levels of procrastination, and the positive association between DI and depressive symptoms was stronger among individuals high in procrastination. No moderation emerged for EV, suggesting that circadian stability may be more relevant to emotional well-being than evening preference per se. When procrastination was included, conscientiousness no longer predicted depressive symptoms, indicating that procrastination may account for the link between low conscientiousness and depression. These findings underscore the importance of self-regulatory behaviors in the circadian-depression relationship.

Circadian rhythms in physiology are coordinated daily variations driven by endogenous oscillators and synchronized by environmental light-dark cycles. Chronic disruption of the natural photoperiod has been associated with circadian desynchronization and physiological impairment. To examine these effects, we exposed adult lean male Neotomodon alstoni to an irregular photoperiod composed of alternating short and long cycles over a week, with abrupt phase shifts and maintained for three consecutive months. Behavioral, physiological, and molecular parameters were assessed, focusing on hypothalamic expression of circadian clock genes (Per1, Bmal1), metabolic regulators (Mchr1, Crh, Prepro-orexin, Sirt1), and feeding-related genes (Npy, Lepr). The irregular photoperiod differentially altered locomotor rhythms depending on phase delays or advances and increased food consumption during the photophase. Nocturnal expression of clock and metabolism-related genes was also modified in the hypothalamus. However, body weight, total food intake, and glucose handling remained unchanged. These findings indicate that in N. alstoni, chronic exposure to an irregular photoperiod disrupts circadian organization of activity and hypothalamic gene expression suggesting that a compensatory mechanisms may preserve overall metabolic homeostasis.

Dim light melatonin onset (DLMO) is the gold standard circadian phase marker in humans. Although several methods can be employed to estimate DLMO, no research has compared agreement across methods using data from pediatric populations. Here, we compared salivary DLMO calculated using four different methods, including two fixed thresholds (3 pg/ml and 4 pg/ml) and two individual thresholds (2 SD above baseline and the "hockey stick" method) in data from 49 children (M = 4.40 ± 0.66 y, 57% female). Intraclass correlations among the four methods were all significant (p < 0.001), with the strongest agreement observed between the 3 pg/ml, 4 pg/ml, and hockey stick methods. DLMO values from all methods were positively correlated with sleep timing (p < 0.001). Although the 2 SD method was more discrepant from the other three estimation methods on average, it did yield a more plausible DLMO estimate in one individual identified as a high secretor. Overall, our findings suggest the 3 pg/ml, 4 pg/ml, and hockey stick methods provide reliable estimates of DLMO in young children, whereas the 2 SD method may allow a more accurate DLMO estimation in edge cases of high or low melatonin secretors.

Hand injuries frequently cause significant functional limitations, and patient engagement plays a crucial role in rehabilitation outcomes. Chronotype represents an individual's inherent preference for activity timing and has been linked to variations in physical performance, pain sensitivity, and cognitive abilities; yet its impact within rehabilitation contexts remains insufficiently studied. This study aimed to investigate whether functional performance, pain, edema, and therapist-rated participation during the morning and afternoon rehabilitation sessions differ according to patients' chronotypes following hand injuries. A prospective observational study was conducted with 46 patients (mean age 39.9 ± 17.1 y) undergoing hand rehabilitation. Chronotype was assessed using the Morningness-Eveningness Questionnaire, and each participant attended two rehabilitation sessions on consecutive days - one in the morning (09:00) and one in the afternoon (16:00). Outcome measures included grip strength, the Nine-Hole Peg Test (NHPT), the Visual Analog Scale (VAS) for pain, physiotherapist-rated VAS for participation, metacarpophalangeal (MCP) joint circumferential edema, and QuickDASH scores. Data were analyzed using a three-way mixed-model repeated-measures ANOVA. Chronotype distribution was 41.3% morning-type, 45.7% intermediate-type, and 13.0% evening-type. Morning and intermediate types demonstrated significantly better NHPT performance in the morning sessions (p < 0.05), whereas evening types showed numerically better performance in the afternoon sessions, although this difference did not reach statistical significance. Intermediate and evening types exhibited significantly higher pain VAS scores in the afternoon sessions (p < 0.01). No significant chronotype-related differences were observed in grip strength, edema, or participation scores. This study is among the first to examine the effects of chronotype on hand injury rehabilitation. The findings suggest that scheduling rehabilitation in alignment with a patient's chronotype may enhance functional performance. However, to generalize these findings, studies with larger sample sizes, more homogeneous chronotype distributions, long-term follow-up, and inclusion of cognitive function assessments are needed.

The menstrual cycle is a biological rhythm, the effects of which are challenging to investigate due to important variability in cycle characteristics, including cycle duration, both between and within individuals. Here, we introduce a tool that calculates this variability, identifies menstrual phases and even more granular menstrual windows, and enables an efficient illustration of results on a circular plot, or menstrual clock. A degree angle approach is used, graduating the follicular phase (menses to ovulation) from 0° to 180° and the luteal phase (ovulation to next menses) from 180° to 360°. This approach enables comparisons between cycles of different duration and the visualization of the distribution of events (symptoms or treatment) and variation of levels (temperature, metabolites, secondary effects, etc.) across the cycle. The open access MenstrualClock R package, incorporating this method in four functions, has been created to facilitate its implementation in research. By calculating menstrual cycle angles, the menstrual clock method provides a convenient tool that can be used to standardize and visualize menstrual cycle phase. Future studies can test the tool against hormone profiles and develop it further to advance research about menstrual cycle effects.