Social jetlag and risk of depression: Results from the Korea National Health and Nutrition Examination Survey

Sex differences in the association between social jetlag and hazardous alcohol consumption in Korean workers: A nationwide cross-sectional study

BACKGROUND

Social jetlag, the misalignment between biological and social rhythms, can lead to adverse health outcomes. This study explored the association between social jetlag and hazardous alcohol consumption, as well as the sex differences in this association.

METHODS

This study included a nationally representative sample of Korean workers consisting of 11,462 individuals (5479 women). Social jetlag was calculated as the difference in the mid-point between sleep onset and offset on free days and workdays. Hazardous alcohol consumption was determined using the Alcohol Use Disorder Identification Test-Consumption (range 0-12), with a cutoff of ≥6 for men, ≥5 for women, and ≥3 for those aged ≥65. Logistic regression analysis was used to estimate the odds ratios (ORs) and 95 % confidence intervals (CIs).

RESULTS

Among men, 599 out of 5983 individuals (10.0 %) had ≥120 min of social jetlag. Among women, 550 out of 5479 individuals (10.0 %) had ≥120 min of social jetlag. The prevalence of hazardous alcohol use was 56.2 % for men and 27.3 % for women. In the regression analysis, there was a significant sex interaction, where social jetlag ≥120 min was associated with hazardous alcohol consumption in female workers (OR: 1.52, 95 % CI: 1.18-1.96), but not in male workers (OR: 1.04, 95 % CI: 0.84-1.29).

CONCLUSION

High social jetlag was associated with an increased likelihood of hazardous alcohol consumption among women. Our findings underscore the importance of considering sex differences in future research and policy interventions regarding social jetlag and its associated behavior outcomes.

Association between weekend catch-up sleep and depressive symptoms in American adults: Finding from NHANES 2017-2020

BACKGROUND

The effect of weekend catch-up sleep (WCS) on depressive symptoms is inconsistent among different populations, with limited evidence in Americans. Therefore, we aimed to investigate the association between WCS and depressive symptoms in American adults.

METHODS

We recruited 7719 participants from the National Health and Nutrition Examination Survey (NHANES) 2017-2020. Information on sleep duration and depressive symptoms were assessed by several self-reported questions and Patient Health Questionnaire-9 (PHQ-9), respectively. Then, WCS duration was calculated as weekend sleep duration minus weekday sleep duration, and WCS was further defined as WCS duration >0 h. Survey designed regression analyses were used to assess the association of WCS and depressive symptoms.

RESULTS

In fully adjusted multivariate logistic regression models, the odds ratio (95 % confidence interval) for depressive symptoms and the β (95 % confidence interval) for PHQ-9 score in response to WCS were 0.746 (0.462, 1.204; P = 0.218) and -0.429 (-0.900, 0.042; P = 0.073), respectively. Besides, the smooth relationship presented L-shaped, and only WCS duration of 0-2 h was statistically significantly associated with depressive symptoms or PHQ-9 score. Subgroup analyses showed that the negative associations were stronger among men, adults younger than 65 years, and those with short weekday sleep duration (P for interaction <0.05).

LIMITATIONS

The cross-sectional design limits the capability for causal relationship between WCS and depressive symptoms.

CONCLUSIONS

This study suggests that moderate WCS is associated with reduced odds of depressive symptoms, which provides additional epidemiological evidence for the effects of sleep on depressive symptoms.

Association between social jetlag and self-rated health: Evidence from Korean representative working population

BACKGROUND

Social jetlag is a circadian misalignment that arises from a discrepancy between activity/sleep schedules on school/work days and free days. This study explored the correlation between social jetlag and self-rated health (SRH) in a representative sample of Korea.

METHODS

This study included 8259 working population in the Korea National Health and Nutrition Examination Survey, 2016-2018. Social jetlag was calculated as the difference between the midpoint of sleep time on work day and work-free day. Five-point Likert scale of SRH was used to assess subjective health perception on general health conditions. Multiple logistic regression analysis was performed to calculate the odds ratios (ORs) and 95 % confidence interval (CI) for poor SRH in the 1-2 h or longer than 2 h social jetlag groups compared to that in the reference group (less than 1 h), after adjusting for age, sex, marital status, occupation, household income, and weekly working hours.

RESULTS

The proportions of those with <1 h, 1-2 h, >2 h of social jetlag were 63.80 %, 25.67 %, and 10.53 %, respectively. The risk of poor SRH increased as social jetlag increased. Greater social jetlag was significantly associated with an increased likelihood of reporting poor SRH. The adjusted ORs for the groups with social jetlag between 1 and <2 h, and >2 h were 1.100 (95 % CI = 0.935-1.295), and 1.503 (95 % CI = 1.097-1.727), respectively. Moreover, the OR trend was statistically significant (p for trend = 0.008).

CONCLUSION

This study found that social jetlag and poor SRH were significantly related in the Korean working population.

The association between social jetlag and depression is independent of sleep debt

OBJECTIVES

To investigate whether the association between SJLsc (sleep-corrected social jetlag) and depressive mood is significant and independent of sleep debt.

METHODS

Participants from the general adult population were interviewed using structured questionnaires on sleep duration, weekday/weekend sleep schedules, and depressive mood (Patient Health Questionnaire-9). Social jetlag (SJL) was measured by SJLsc and standard SJL (SJLs). SJLs was the absolute difference between mid-sleep time on free days (MSF) and workdays (MSW). For SJLsc, both MSF and MSW were adjusted for average sleep duration across the week according to the direction of sleep debt. Sleep debt was defined by sleep extension on free days. The association of SJL with depression was investigated, and covariates included age, sex, sociodemographic factors, insomnia symptoms, sleep duration, and sleep debt.

RESULTS

A total of 1982 individuals (1089 men; age 43.1 ± 14.4 years) were analyzed. SJL was present in 24.6% measured by SJLsc and 51.0% by SJLs. SJLsc and SJLs were significantly associated with depressive mood (r = 0.06, P = 0.02; r = 0.06, P = 0.01, respectively), independent of sleep debt. Sleep debt was also associated with depression (r = 0.07, P < 0.01).

CONCLUSIONS

By adopting sleep-corrected formula for SJL, this study found that misaligned and insufficient sleep, at levels occurring in routine social life, can negatively affect mood. Minimizing social jetlag and sleep deprivation may promote individual psychological well-being.

Mediation analysis of chronotype, sleep-related factors, and depressive symptoms among workers: a cross-sectional study

Background

This study aimed to examine the impact of chronotype on depressive symptoms and explore the mediating effects of sleep quality, pre-sleep cognitive arousal, and social jetlag in a sample of wage earners.

Methods

A total of 3,917 waged workers were surveyed online in July 2022. Logistic regression and mediation analysis were used to assess the relationship between chronotype (morningness, intermediate, and eveningness) and depressive symptoms (Patient Health Questionnaire ≥ 5), and the mediating effects of Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), and Pre-Sleep Arousal Scale (PSAS). All analyses were adjusted for age, education level, income level, marital status, coffee consumption, alcohol consumption, physical activity, occupation, employment status, and working hours to calculate odds ratios (ORs).

Results

The chronotypes of all the participants were divided into morningness (4.7%), intermediate (93.5%), and eveningness (1.8%). Multiple logistic regression analysis showed an increased risk of depression in the eveningness chronotype (OR: 2.96; 95% confidence interval [CI]: 1.51, 5.86). Regarding the mediation analysis, ISI mediated 28.44% (95% CI: 16.39-40.5), PSQI for 31.25% (95% CI: 19.36, 43.15), and PSAS-Cognitive Score (PSAS-C) for 23.58% (95% CI: 10.66, 36.50) of the association between chronotype and depressive symptoms. However, social jetlag did not significantly mediate this relationship. (percentage mediated = 0.75%, 95% CI: -3.88, 5.39).

Conclusions

Evening chronotypes exhibit an increased risk of depressive symptoms, which ISI, PSQI, and PSAS-C partially mediated. This suggests that interventions to improve sleep quality and maintain adequate sleep habits may effectively prevent and treat depression in employees with an eveningness chronotype.

An Examination of the Associations between Nutritional Composition, Social Jet Lag and Temporal Sleep Variability in Young Adults

While dietary intake has previously been related to various indices of poor sleep (e.g., short sleep duration, poor sleep quality), to date, few studies have examined chrononutrition from the perspectives of the relationship between dietary intake and social jet lag and temporal sleep variability. Moreover, recently it has been suggested that previous methods of measuring social jet lag have the potential to lead to large overestimations. Together, this precludes a clear understanding of the role of nutritional composition in the pathophysiology of poor sleep, via social jet lag and temporal sleep variability, or vice versa. The aim of the present study was to determine the relationships between nutrient intake and social jet lag (using a revised index, taking account of intention to sleep and sleep onset and offset difficulties), and temporal sleep variability. Using a cross-sectional survey, 657 healthy participants (mean age 26.7 ± 6.1 years), without sleep disorders, were recruited via an online platform and completed measures of weekly dietary intake, social jet lag, temporal sleep variability, stress/sleep reactivity and mood. Results showed limited associations between nutritional composition and social jet lag. However, levels of temporal sleep variability were predicted by consumption of polyunsaturated fats, sodium, chloride and total energy intake. The results suggest further examinations of specific nutrients are warranted in a first step to tailoring interventions to manage diet and temporal variabilities in sleep patterns.

Associations of social jetlag with depressive symptoms among adults in Southern China: a cross-sectional study

To investigate the associations between social jetlag and depressive symptoms and further analyze the interaction of social jetlag and chronic diseases on depressive symptoms among adults. Data were derived from a cross-sectional survey. Information on social jetlag, depressive symptoms, demographic characteristics, lifestyles, and health situations were collected via a structured self-administered questionnaire. The multivariable logistic regression analyses and restricted cubic splines regression were performed to test the association between social jetlag and depressive symptoms. The multiplicative model was applied to analyze the interaction of social jetlag and chronic disease on depressive symptoms. A total of 5818 adults were included and the prevalence of social jetlag was 22.95%. After multivariable adjustment, adults who experienced more than 2 hours of social jetlag had a significantly greater risk of depressive symptoms (OR = 1.43,95%CI:1.00-2.05, P = 0.049). Compared with participants having<1 hour of social jetlag and no chronic disease, participants having chronic disease were more likely to report depressive symptoms(OR = 3.22,95%CI = 2.59-4.00, P < 0.001). Moreover, among those who have chronic disease, the greater the social jetlag they reported, the greater risk of depressive symptoms they have (OR = 3.81,95%CI = 2.77-5.33, P < 0.001; OR = 4.08,95%CI = 2.24-7.43, P < 0.001). Social jetlag was linearly associated the with risk of depressive symptoms, according to restricted cubic splines. This study shows that 22.95% adults experience more than 1 hour of social jetlag. Social jetlag was positively associated with an increased risk of depressive symptoms. Among those who have chronic disease, the greater the social jetlag they reported, the greater risk of depressive symptoms they have.