The bidirectional relationship between sleep duration and depression in community-dwelling middle-aged and elderly individuals: evidence from a longitudinal study

Lifestyle factors, physical health, and life satisfaction under different changes in depressive symptoms among Chinese community-dwelling older adults: A longitudinal analysis

BACKGROUND

The study aims to investigate the long-term impact of lifestyle-related factors and physical health on life satisfaction and depressive symptoms among Chinese community-dwelling older adults.

METHODS

Using data from the China Health and Retirement Longitudinal Study (CHARLS), the analytic sample of this study included 1,068 older adults who had participated in the surveys in both 2011 and 2018. Multivariate regression was employed to analyze both cross-sectional and longitudinal relationships between lifestyle-related factors, physical health, and subjective well-being - specifically depressive symptoms and life satisfaction. Additionally, the model tested how these factors correlate with life satisfaction across different groups of depressive symptom changes among older adults, categorized as not at risk of depression, intermittent depression, and chronic depression.

RESULTS

Multimorbidity was significantly related to baseline and follow-up depressive risk in older adults. Shorter sleep duration was associated with baseline depression risk. Current alcohol drinkers reported significantly more severe depressive symptoms than non-drinkers. At baseline, current smokers were more likely to have a lower degree of life satisfaction than nonsmokers. Among older adults with chronic depression at the 7-year follow-up, former smokers tended to have lower life satisfaction than nonsmokers.

CONCLUSIONS

Our findings identified drinking alcohol and having a shorter sleep duration as modifiable lifestyle-related risk factors for late-life depression and smoking as a detrimental factor for life satisfaction in older Chinese adults. Multimorbidity was a significant predictor of more depressive symptoms. Our findings have implications for future psychosocial interventions that target the alleviation of depressive symptoms and the promotion of life satisfaction in older Chinese people based on their different long-term mental and physical health conditions.

Sleep Duration Differences by Education from Middle to Older Adulthood: Does Employment Stratification Contribute to Gendered Leveling?

Sleep duration changes across the life course and differs by education in the United States. However, little research has examined whether educational differences in sleep duration change over age-or whether sleep duration trajectories over age differ by education. This study uses a life course approach to analyze American Time Use Survey data (N = 60,908), examining how educational differences in weekday sleep duration change from middle to older adulthood (ages 40-79). For men only, differences in total sleep time between individuals with less than a high school degree and those with more education converge in older adulthood. Results suggest that this leveling is explained by decreasing educational stratification in work hours as men enter older adulthood. Findings highlight the importance of employment for shaping gendered socioeconomic differences in sleep and demonstrate differences by education in how sleep duration changes over age, with possible implications for health disparities.

Sleep Duration and Functional Disability among Chinese Older Adults: A Cross-Sectional Study

BACKGROUND

Duration of sleep has a crucial role in the development of physiological functions that impact health. Little is known about the associations between sleep duration and functional disability among the older adults in China.

OBJECTIVE

This study aims to explore the associations between sleep duration and functional disabilities in the older population aged 65 years and above in China.

METHODS

The data for this cross-sectional study were gathered from respondents aged 65 years and above who participated in the 2018 survey of China Health and Retirement Longitudinal Study, an ongoing nationwide longitudinal investigation of Chinese adults. The duration of sleep per night was obtained through face-to-face interviews. Functional disability was assessed using activities of daily living (ADL) and instrumental activities of daily living (IADL). The association between sleep duration and functional disability was assessed by multivariable generalized linear model. Restricted cubic spline model was used to explore the dose-response relationship between sleep duration and functional disability.

RESULTS

In total, 5 519 participants [Male: 2 471 (44.77%)] were included in this study with a mean age of 73.67 years old, containing 2 800 (50.73%) functional disabled, 1 978 (35.83%) ADL disabled, and 2 299 (41.66%) IADL disabled older adults. After adjusted for potential confounders, individuals reported shorter sleep durations (≤ 4, 5, 6 hours) or longer sleep durations (8, 9, ≥ 10 hours) per night exhibited a notably increased risk of functional disability compared to those who with 7 hours (P < 0.05), which revealed a U-shape association between sleep duration and dysfunction. When sleep duration fell below 7 h, increased sleep duration was associated with a significantly lower risk of functional disability (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.79-0.91; P < 0.001). When sleep duration exceeded 7 h, the risk of functional disability (OR, 1.16; 95% CI, 1.05-1.29; P < 0.001) would increase facing prolonged sleep duration.

CONCLUSIONS

Shorter and longer sleep duration was associated with a higher risk of functional disability among the aged 65 and above Chinese adults. Future studies are needed to explore intervention strategies about sleep duration especially focus on functional disability.

CLINICALTRIAL

Instrumental activities of daily living function and cognitive status among Chinese older adults: a serial multiple mediation model

Objective

This study aimed to develop and validate a serial multiple mediation model to investigate the association between instrumental activities of daily living (IADL) function and cognitive status among older adults while exploring the underlying mechanisms.

Methods

This cross-sectional study involved 3,665 individuals aged 60 years and older who participated in the China Health and Retirement Longitudinal Survey (CHARLS). A serial multiple mediation model was utilized to explore the direct and indirect relationship between IADL function and cognitive status and whether sleep duration, social engagement, and depressive symptoms mediated this relationship.

Results

Decreased IADL function was associated with worse cognitive status [effect = -0.620, 95% CI: (-0.692, -0.540)]. Sleep duration, social participation (SP), and depressive symptoms all acted as mediators in the relationship between IADL function and cognitive status.

Conclusion

This study found both direct and indirect associations between IADL function and cognitive status, providing new insights into the effective prevention and intervention of cognitive decline among older adults.

An Ensemble Classification Model for Depression Based on Wearable Device Sleep Data

Depression is one of the most common mental disorders, with sleep disturbances as typical symptoms. With the popularity of wearable devices increasing in recent years, more and more people wear portable devices to track sleep quality. Based on this, we believe that depression detection through wearable sleep data is more intelligent and economical. However, the majority of wearable devices face the problem of missing data during the data collection process. Otherwise, most existing studies of depression identification focus on the utilization of complex data, making it difficult to generalize and susceptible to noise interference. To address these issues, we propose a systematic ensemble classification model for depression (ECD). For the missing data problem of wearable devices, we design an improved GAIN method to further control the generation range of interpolated values, which can achieve a more reasonable treatment of missing values. Compared with the original GAIN approach, the improved method shows a 28.56% improvement when using MAE as the metric. For depression recognition, we use ensemble learning to construct a depression classification model which combines five classification models, including SVM, KNN, LR, CBR, and DT. Ensemble learning can improve the model's robustness and generalization. The voting mechanism is used in several places to improve noise immunity. The final classification model performed great on the dataset, with a precision of 92.55% and a recall of 91.89%. These results illustrate how efficient this method is in automatically detecting depression.

Latent profile analysis of depression in US adults with obstructive sleep apnea hypopnea syndrome

Objective

This study used latent profile analysis to explore the level of depression among US adults with obstructive sleep apnea hypopnea syndrome (OSAHS) symptoms and to identify different latent categories of depression to gain insight into the characteristic differences between these categories.

Methods

The data of this study were obtained from the National Health and Nutrition Examination Survey (NHANES) database, and the subjects with OSAHS symptoms were aged 18 years and older. The latent profile analysis (LPA) method was used to fit the latent depression categories in subjects with OSAHS symptoms. The chi-square test, rank sum test, and binary logistic regression were used to analyze the influencing factors of depression subgroups in subjects with OSAHS symptoms.

Results

Three latent profiles were identified: low-level (83.7%), moderate-level (14.5%) and high-level (1.8%) depression. The scores of 9 items in the high-level depression group were higher than those in the other two groups. Among them, item 4 "feeling tired or lack of energy" had the highest score in all categories.

Conclusion

Depression in subjects with OSAHS symptoms can be divided into low-level, moderate-level and high-level depression. There are significant differences among different levels of depression in gender, marital status, PIR, BMI, smoking, general health condition, sleep duration and OSAHS symptom severity.

Association between weekend catch-up sleep and depression of the United States population from 2017 to 2018: A cross-sectional study

Insufficient sleep on weekdays has become a societal norm, and studies have shown that sleep deprivation increases the risk of depression. Although individuals often resort to weekend catch-up sleep (CUS) as a compensatory measure, the present evidence supporting its efficacy in mitigating the risk of depression is limited. This article attempts to explore the relationship between CUS and depression. In this study, a total of 5510 participants were included, characterized into two groups: nondepressed (n = 5051) and depressed (n = 459), with data extracted from the National Health and Nutrition Examination Survey (NHANES). Compared with people without CUS, those practicing CUS exhibited a significantly lower risk of depression (OR = 0.81, P = 0.048). In subgroup analysis, this reduction effect was only observed in males (OR = 0.70, 95 % CI 0.05 to 0.99, P = 0.04), middle-aged (>40, ≤60) (OR: 0.57, 95 % CI: 0.40 to 0.81, P = 0.002), married or living with parents (OR: 0.61, 95 % CI: 0.44 to 0.86, P = 0.004), groups with three or more family members (OR: 0.69, 95 % CI: 0.52 to 0.93, P = 0.01), and individuals without alcohol intake (OR: 0.24,95 % CI: 0.09 to 0.67, P = 0.006). Therefore, in the realm of depression treatment, doctors may consider advising patients to get adequate sleep on weekends as part of their overall treatment plan. At the same time, individuals can also choose weekend sleep as a proactive strategy for regulating their psychological status.

Worldwide prevalence of sleep problems in community-dwelling older adults: A systematic review and meta-analysis

The understanding of the prevalence of sleep problems in older adults can provide a broad and reliable perspective into the occurrence of such issues among older adults. This systematic review and meta-analysis aimed to estimate the worldwide prevalence of sleep problems in community-dwelling older adults. Studies that provide information on the prevalence of sleep problems in community-dwelling older adults (≥60 years) were screened between December 2022 and March 2023. A total of 20,379 studies were identified in database searches, from which 252 were included in this review. These studies covered the last 35 years (from 1988 to 2023) and pooled a sample of 995,544 participants from 36 countries. The most frequent sleep problem worldwide was obstructive sleep apnea (46.0%), followed by poor sleep quality (40.0%), other sleep problems (37.0%), insomnia (29.0%), and excessive daytime sleepiness (19.0%). No significant difference in the prevalence estimates of all sleep problems was observed between the sexes. This systematic review and meta-analysis showed a high prevalence of some sleep problems, mainly obstructive sleep apnea, poor sleep quality, and other sleep problems. Our estimates can be useful for managers and policymakers in planning healthcare strategies for sleep problems aimed at the older population.

Isotemporal substitution analysis of time between sleep, sedentary behavior, and physical activity on depressive symptoms in older adults: a cross-sectional study

BACKGROUND

Compared to young individuals, older adults participate more in sedentary behavior (SB) and less in physical activity (PA). These behaviors are associated with numerous adverse health factors.

OBJECTIVE

The purpose of the study was to examine the hypothetical effects of substituting time spent sleeping, performing SB, and performing moderate-to-vigorous physical activity (MVPA) on depressive symptomatology in older adults.

DESIGN AND SETTING

An analytical cross-sectional study employing exploratory survey methods was conducted in the city of Alcobaça in the state of Bahia, Brazil.

METHODS

The study included 473 older adults who answered a structured questionnaire during an interview. Exposure time to SB and PA level were assessed using the International Physical Activity Questionnaire, and depressive symptoms were analyzed using the short version of the Geriatric Depression Scale. An isotemporal replacement model was used to evaluate the effects of different SB sessions on depressive symptomatology.

RESULTS

An increase in the risk of depressive symptoms was observed when MVPA and sleep time were substituted for the same SB time at all times tested, with maximum values of 40% and 20%, respectively. Opposite substitution of MVPA and sleep time increments reduced the risk of depressive symptomatology by 28% and 17%, respectively.

CONCLUSIONS

The results of the present study indicate that replacing SB with the same amount of sleep or MVPA may reduce depressive symptoms. The longer the reallocation time, the greater are the benefits.

Association of cardiovascular health using Life's Essential 8 with depression: Findings from NHANES 2007-2018

OBJECTIVE

Few studies have explored the correlation between cardiovascular health (CVH) and depression. We aimed to investigate the relationship between CVH using Life's Essential 8 (LE8) and depression among US adults.

METHODS

16,362 individuals from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018 were included. The patient Health Questionnaire (PHQ-9) was utilized to recognized depression (PHQ-9 ≥ 10). LE8 was scored by four health behaviors (sleep, tobacco/nicotine exposure, physical activity and diet) and four health factors (body mass index, non-high-density lipoprotein cholesterol, blood glucose and blood pressure) and classified into low, moderate and high CVH groups. Weighted logistic regressions, restricted cubic splines and sensitivity analyses were utilized to investigate the correlation between LE8 and depression.

RESULTS

1306 subjects had depression (7.98% of the participants), of which 860 (7.42%), 305 (17.24%) and 141 (3.01%) had low, moderate and high CVH, separately. In the fully adjusted model, LE8 was negatively correlated with depression (OR: 5.50, 95% CI 3.92-7.71, P < 0.001). Furthermore, there were inversely dose-response relationships between LE8 and depression (overall P < 0.001).

CONCLUSIONS

Adhering to a high CVH, estimated by the LE8 score, was correlated with lower odds of depression.

Polysomnography and Neuropsychological Analysis of Patients With Post-Traumatic Stress Disorder Two Years After the COVID-19 Pandemic in Wuhan

OBJECTIVE

We used polysomnography (PSG) monitoring and neuropsychological scales to explore the characteristics of coronavirus disease-2019 (COVID-19) patients diagnosed with post-traumatic stress disorder (PTSD) in Wuhan, two years after the onset of the COVID-19 pandemic.

METHODS

A total of 42 patients in the Sleep Medicine Center were diagnosed with insomnia between December 2021 and May 2022; they were divided into the PTSD group (patients with PTSD diagnosed with insomnia after COVID-19 infection) and the non-PTSD group (patients with insomnia without PTSD). A healthy control group was simultaneously included.

RESULTS

The PTSD group was more significant than the non-PTSD group in partial manifestations of sleep disorders, neuropsychological clinical symptoms, and partial PSG data. Patients with different COVID-19 subtypes showed significant differences in the course of disease, sleep disorders, neuropsychological clinical symptoms, relevant scale scores, and PSG data analysis.

CONCLUSION

The emotional anxiety and depression of COVID-19 patients diagnosed with PTSD two years after the COVID-19 pandemic in Wuhan are more significant, and will not be self-alleviated with the passage of time. It is necessary to continue to pay attention to the PTSD symptoms and sleep psychology of COVID-19 infected patients, and take appropriate measures. Patients with severe and critical COVID-19 have more severe sleep and mental disorders, and there is a significant correlation between the duration of the disease and the severity of mental and mental disorders and sleep disorders after recovery.

Association between sleep duration and depression in menopausal women: a population-based study

Aims

This research investigated menopausal women older than 50 years to find whether there were any independent relationships between the duration of sleep they got and their prevalence of depression.

Methods

National Health and Nutrition Examination Survey (NHANES) datasets from 2011-2020 were utilized in a cross-sectional study. Using multivariate linear regression models, the linear relationship between sleep duration and depression in menopausal women was investigated. Fitted smoothing curves and thresholds impact evaluation were used to investigate the nonlinear relationship. Then, subgroup analyses were performed according to smoking, drinking alcohol, diabetes, hypertension, heart disease, and moderate activities.

Results

This population-based study included a total of 3,897 menopausal women (mean age 65.47 ± 9.06 years) aged≥50 years; 3,159 had a depression score <10, and 738 had a depression score≥10. After controlling for all covariates, the prevalence of depression was 17% higher among participants with short sleep duration [OR=1.17, 95%CI=(0.65, 1.70), P<0.0001] and 86% [OR=1.86, 95%CI=(1.05, 2.66), P<0.0001] compared to participants with normal sleep duration. In subgroup analyses stratified by smoking and diabetes, the sleep duration and depression scores of non-smokers [β=-0.18, 95%CI= (-0.33, -0.02), P=0.0241] and diabetics were independently negatively correlated [β=-0.32, 95%CI= (-0.63, -0.01), P=0.0416]. Using a two-segment linear regression model, we discovered a U-shaped relationship between sleep duration and depression scores with an inflection point of 7.5 hours. Less than 7.5 hours of sleep was associated with an increased risk of developing depression [β=-0.81, 95%CI= (-1.05, -0.57), P<0.001]. However, sleeping more than 7.5 hours per night increased the risk of depression considerably [β=0.80, 95%CI= (0.51, 1.08), P<0.001].

Conclusions

Depression is associated with sleep duration in menopausal women. Insufficient or excessive sleep may increase the risk of depression in menopausal women.

Habitual Sleep Duration and Health-Related Quality of Life in Family Caregivers: Findings from the Behavioral Risk Factor Surveillance System

BACKGROUND

Insufficient sleep duration is associated with poor health-related quality of life (HRQoL). However, this relationship has not been studied in family caregivers, a group at high risk of insufficient sleep duration and poor HRQoL.

OBJECTIVE

To examine the associations between habitual sleep duration and HRQoL measures in family caregivers.

METHODS

This cross-sectional study used data from 23,321 caregivers in the 2016 Behavioral Risk Factor Surveillance System. The HRQoL measures were health status and poor mental and physical health days. A multivariable logistic regression model was used to assess the association between sleep duration (<7, 7-9, >9 hours) and health status (fair or poor versus good to excellent). Zero-inflated negative binomial models were used to analyze the association of sleep duration with poor mental and physical health days.

RESULTS

Fair or poor health status was significantly higher in caregivers with short (odds ratio [OR], 1.40; 95% CI: 1.12, 1.74) and long (OR, 2.07; 95% CI: 1.34, 3.21) sleep duration. Short sleep duration was associated with a higher number of poor mental health days (IRR [incident rate ratio], 1.17; 95% CI: 1.04, 1.31) and poor physical health days (IRR, 1.26; 95% CI: 1.10, 1.45). Long sleep duration was associated with more poor mental health days (IRR, 1.31; 95% CI: 1.08, 1.60).

CONCLUSION

Extremes in sleep duration were associated with lower HRQoL. These findings point to the need for interventions that promote adequate sleep and address factors underlying extremes in sleep duration in the context of family caregiving.

Quantile regression to explore association of sleep duration with depression among adults in NHANES and KNHANES

BACKGROUND

Sleep duration has been associated with depression. However, mean regression, such as linear regression or logistic regression, may not capture relationships that occur mainly in the tails of outcome distribution. This study aimed to evaluate the associations between sleep duration and depression along the entire distribution of depression using quantile regression approach.

METHODS

This study included 55,954 adults aged 18 to 80 years from the National Health and Nutrition Examination Survey (N = 34,156) and the Korea National Health and Nutrition Examination Survey (N = 21,798). The coefficients corresponding to cross-group differences in PHQ-9 scores were estimated when comparing short or long sleep duration with normal sleep duration on deciles of PHQ-9 score distribution.

RESULTS

At lower quantiles, either short or long sleep duration was not associated with depression. At higher quantiles, the association of both short and long sleep duration with depression became much more pronounced. Compared with normal sleep duration, short and long sleep duration were associated with increases of 1.34 (95 % CI: 1.16, 1.51) and 0.28 (95 % CI: 0.04, 0.52) in PHQ-9 scores at the 50th quantile, while the corresponding increases were 3.27 (95 % CI: 2.83, 3.72) and 1.65 (95 % CI: 0.86, 2.45) at the 90th quantile, respectively. We also found that the magnitude of association between short sleep duration and depression was stronger among females and individuals with chronic diseases.

CONCLUSIONS

The beneficial effect of sufficient sleep in decreasing depression severity may be more evident among individuals with severe depression. Further studies could explore whether these heterogeneous associations can be generalized to populations with different characteristics.

Barriers and Facilitators to Participation and Key Components of Sleep Health Programs: Perspectives for the Corporate Work Environment

OBJECTIVE

The aim of the study is to explore the barriers and facilitators of participation and key components for sleep health programs designed for corporate work environments.

METHODS

Semistructured interviews with corporate executives and occupational medicine specialists in the decision making and management of workplace health promotion programs (WHPP) within their companies were held before and during COVID-19. Interviews were transcribed verbatim and analyzed using thematic content analysis to identify themes.

RESULTS

Barrier and facilitator themes emerging from the data include sleep health awareness, work culture, work-family balance, and confidentiality. Key components for sleep health programs included the following: identifying the need for a program, incorporating sleep health risk screening to WHPP, and promoting sleep health by raising awareness thereof.

CONCLUSIONS

The identified barriers and facilitators to employee participation and key components of an ideal sleep health program provide guidance for further WHPP.

How do the sleep features that characterise depression impact memory?

Depression is associated with general sleep disturbance and abnormalities in sleep physiology. For example, compared with control subjects, depressed patients exhibit lower sleep efficiency, longer rapid eye movement (REM) sleep duration, and diminished slow-wave activity during non-REM sleep. A separate literature indicates that depression is also associated with many distinguishing memory characteristics, including emotional memory bias, overgeneral autobiographical memory, and impaired memory suppression. The sleep and memory features that hallmark depression may both contribute to the onset and maintenance of the disorder. Despite our rapidly growing understanding of the intimate relationship between sleep and memory, our comprehension of how sleep and memory interact in the aetiology of depression remains poor. In this narrative review, we consider how the sleep signatures of depression could contribute to the accompanying memory characteristics.

Sleep Duration and Insomnia with Comorbid Depression and Anxiety Symptoms in Chinese Adults: A Cross-Sectional Study

Purpose

Depression and anxiety are two highly prevalent mental disorders that commonly coexist. However, little is known about the association between sleep and comorbid depressive and anxiety symptoms (CDAS). Therefore, this study aims to explore the relationship between sleep duration, insomnia and CDAS.

Methods

This is a cross-sectional study of 22,004 community adults who participated in the China Multi-Ethnic Cohort (CMEC) study. Chinese version of Patient Health Questionnaire-2 and Generalized Anxiety Disorder-2 were used to screen CDAS in community adults. A positive score on each scale was considered indicative of CDAS. All participants received face-to-face interviews, medical examinations, and biochemical examinations to assess sleep duration and insomnia and collect covariates. The self-reported sleep duration was divided into three groups: <7 hr, 7-9 hr and >9 hr groups. Logistic regression was used to analyze the association between sleep duration, insomnia and CDAS. A restricted cubic spline (RCS) was used to explore the dose-response relationship between sleep duration and CDAS. Stratified analysis based on gender and age was conducted.

Results

Overall, 2.8% (95% CI 2.6%~3.0%) of participants reported having CDAS. After adjusting the potential covariates, sleep duration <7 hr (OR=1.635, 95% CI=1.335~2.004) was significantly associated with CDAS, compared with sleep 7-9 hr. After RCS analysis, there was a nonlinear relationship between sleep duration and CDAS. The increase in the number of types of insomnia, the greater the likelihood of CDAS (p for trend<0.05). In sensitivity analysis, it was found that the results were consistent with those of the main analysis. After stratification by gender and age, the association between sleep duration and CDAS was only observed in female and young and middle-aged adults, not in men and older adults.

Conclusion

Both insufficient sleep duration and insomnia are associated with a higher prevalence of CDAS in Chinese adults.

Relationship between dietary carotenoid intake and sleep duration in American adults: a population-based study

OBJECTIVE

To investigate the relationship between dietary carotenoid intake and sleep duration.

METHODS

Adults enrolled in the National Health and Nutrition Examination Survey (NHANES) 2007-2018 without missing information on dietary carotenoid intake (α-carotene, β-carotene, β-cryptoxanthin, lycopene, and lutein + zeaxanthin), sleep duration, and covariates were included. Participants' carotenoid consumption was divided into three groups by quartiles and sleep duration was grouped as short (< 7 h/night), optimal (7-8 h/night), and long (> 8 h/night). Multinominal logistic regression was constructed to examine the association between dietary carotenoid intake and sleep duration. Restricted cubic spline (RCS) regression was further utilized to explore their dose-response relationship. The weighted quantile sum (WQS) model was adopted to calculate the mixed and individual effect of 5 carotenoid sub-types on sleep duration.

RESULTS

Multinominal logistic regression presented that people with higher intakes of α-carotene, β-carotene, β-cryptoxanthin, lycopene, and lutein + zeaxanthin were less likely to sleep too short or too long. Consistent with the findings from multinominal logistic regression, the RCS models suggested a reverse U-shaped relationship between sleep duration and carotenoid intakes. The mixed effects were also significant, where β-cryptoxanthin and lutein + zeaxanthin were the top 2 contributors associated with the decreased risks of short sleep duration, while β-carotene, α-carotene, and β-cryptoxanthin were the main factors related to the lower risk of long sleep duration.

CONCLUSION

Our study revealed that the American adults with optimal sleep duration were associated with more dietary carotenoid intake, in comparison to short or long sleepers.

Exploring the relationship between work-family conflict and sleep disturbance: a study on stratification and interaction

Introduction

Despite several studies on the association between work-family conflict (WFC) and sleep disturbances, a more comprehensive approach considering occupational factors is lacking. We aimed to analyze this association among Korean workers and the combined effects of WFC and job-related factors on sleep disturbance.

Methods

Data on paid workers from the sixth Korean Working Conditions Survey were analyzed. Odds ratios (ORs) with 95% confidence intervals (CIs) for sleep disturbances with WFC were calculated using a multiple logistic regression model among Korean workers. Furthermore, stratification and interaction analyses were conducted between WFC and socioeconomic factors related to sleep disturbance.

Results

Among the 24,923 workers (male: 11,752, female: 13,171) examined, 35.40% of males and 39.95% of females experienced sleep disturbances. In both sexes, the WFC group was significantly associated with sleep disturbance [adjusted OR (95% CI): male, 2.90 [2.67-3.16]; female, 2.54 [2.35-2.74]]. According to the stratification analysis, the association between sleep disturbance and WFC was prominent among younger and highly educated individuals, those engaged in quick returns, and larger companies in both sexes. In the interactions between WFC, quick return, occupation, and company size on sleep disturbance, there were significant additive associations, except between WFC and occupation among female workers.

Conclusion

This study highlights the association between WFC and sleep disturbances in male and female workers and emphasizes the importance of maintaining work-life balance.

Study on the trajectory of depression among middle-aged and elderly disabled people in China: Based on group-based trajectory model

Background

Previous studies have shown that middle-aged and elderly adults with disabilities are at higher risk for depressive symptoms. However, there are few studies on the long-term trajectories of depressive symptoms in the Chinese middle-aged and elderly disabled population.

Objective

This study aimed to identify the different development trajectories of depressive symptoms and their influencing factors in middle-aged and elderly people with disabilities in China.

Methods

Using data from the China Health and Retirement Longitudinal Study (CHARLS) in 2011, 2013, 2015, and 2018, a longitudinal cohort was formed for the study. A total of 2053 participants underwent at least two measures of depressive symptoms, assessed using the Center for Epidemiological Studies Depression Scale (CES-D10), a depression symptom assessment scale. We constructed a Group-Based Trajectory Model (GBTM) to identify the development trajectory of depressive symptoms in 2053 middle-aged and elderly disabled individuals, screened the potential predictors using lasso regression, and analyzed the factors affecting the development trajectory of depression through multivariate logistic regression.

Results

We identified four depression symptom trajectories throughout the follow-up process: "low depressive symptom group", "worsening depressive symptom group", "relieved depressive symptom group", and "high depressive symptom group". We found that there were differences in basic characteristics among different subgroups of depression trajectory. However, middle-aged and elderly disabled women living in rural areas, with limited ADL or IADL, physical pain, poor self-reported health and self-reported memory, short sleep time, and no relatives and friends to take care of them were the key groups for the prevention and treatment of depressive symptoms.

Conclusion

There is heterogeneity in the trajectories of depressive symptoms in the Chinese middle-aged and elderly disabled population, it is necessary to focus on the characteristics of the trajectories of different subgroups.

Bidirectional temporal associations between sleep and affect and cognitive symptoms among community-dwelling stroke survivors: An ecological momentary assessment study

INTRODUCTION

Sleep plays a critical role in daily functioning and stroke recovery but receives little attention in stroke rehabilitation. Sleep disturbances are linked to affective and cognitive impairments, but temporal associations between sleep and affect and cognitive symptoms are less clear. Understanding these temporal associations may inform new directions in intervention and prevention to support continued stroke recovery.

OBJECTIVE

To examine the bidirectional temporal associations between sleep and affect and cognitive symptoms among community-dwelling stroke survivors.

DESIGN

A secondary analysis of a longitudinal observational study involving 7 days of ecological momentary assessment (EMA), during which participants completed eight EMA surveys and a sleep diary per day. Multilevel modeling was used to analyze data.

SETTING

Community.

PARTICIPANTS

Community-dwelling stroke survivors (N = 40).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

EMA measures of depressed affect, cheerful affect, and cognitive symptoms. Sleep quality and duration as measured using a sleep diary.

RESULTS

Between-person sleep quality was negatively associated with next-day depressed affect (B = -.16; p = .028) and positively associated with next-day cheerful affect (B = .63; p < .001). Inversely, between-person depressed affect was negatively associated with next night sleep quality (B = -.77; p = .015), and vice versa for cheerful affect (between-person: B = .45; p < .001; within-person: B = .09; p = .008). Long sleep (>9 hours) was positively associated with next-day cognitive symptoms (B = .13; p = .002), whereas cognitive symptoms were associated with a higher odds of long sleep the following night (odds ratio [OR] = 0.25; p = .047).

CONCLUSIONS

This study identified the bidirectional associations of sleep with affect and cognitive symptoms in the context of the everyday life of stroke survivors. The findings suggest that interventions addressing sleep quality and duration may impact affect and cognitive symptoms, and vice versa.

Association of Chrononutrition Indices with Anthropometric Parameters, Academic Performance, and Psychoemotional State of Adolescents: A Cross-Sectional Study

Adolescents are an at-risk group for circadian misalignment. The contribution of sleep-wake rhythm instability to the psychoemotional, cognitive, and weight disorders of adolescents has been studied in sufficient detail. At the same time, there is insufficient information about the association between chrononutrition indices and the well-being of adolescents. The aim of this study is to investigate the relationship between chrononutrition indices and academic achievement, psychoemotional state, and anthropometric indicators in adolescents. The study involved 12,759 students in grades 6-11 of secondary schools, aged 14.2 ± 1.7 years old; 57.2% of whom were girls. Participants provided personal data, frequency and time of meals during the day and at night, on weekdays and weekends, and completed the Zung Self-Rating Depression Scale and the Yale Food Addiction Scale. There is a U-shaped association between eating mid-phase (EPFc), eating jetlag (EJL), and eating window (EW) with GPA, ZSDSI, and FA. At the same time, the frequency of night eating (NE) is linearly associated with the studied parameters. NE is the strongest predictor of ZSDSI (β = 0.24), FA (β = 0.04), and GPA (β = -0.22). EPFc, EJL, and EW practically do not differ in the strength of their association with the studied indicators. ZSDSI is most closely associated with the chrononutrition indices. There is a weak negative association between BMI and EW (β = -0.03) and NE (β = -0.04). Thus, circadian eating disorders are more often observed in adolescents with poor academic performance, high levels of depression, and food addiction.

Polygenic predisposition, sleep duration, and depression: evidence from a prospective population-based cohort

Suboptimal sleep durations and depression frequently cooccur. Short-sleep and long-sleep are commonly thought of as symptoms of depression, but a growing literature suggests that they may be prodromal. While each represents a process of mutual influence, the directionality between them remains unclear. Using polygenic scores (PGS), we investigate the prospective direction involved in suboptimal sleep durations and depression. Male and female participants, aged ≥50, were recruited from the English Longitudinal Study of Ageing (ELSA). PGS for sleep duration, short-sleep, and long-sleep were calculated using summary statistics data from the UK Biobank cohort. Sleep duration, categorised into short-sleep ("≤5 h"), optimal-sleep (">5 to <9 h"), and long-sleep ("≥9 h"), was measured at baseline and across an average 8-year follow-up. Subclinical depression (Centre for Epidemiological Studies Depression Scale [≥4 of 7]) was also ascertained at baseline and across an average 8-year follow-up. One standard deviation increase in PGS for short-sleep was associated with 14% higher odds of depression onset (95% CI = 1.03-1.25, p = 0.008). However, PGS for sleep duration (OR = 0.92, 95% CI = 0.84-1.00, p = 0.053) and long-sleep (OR = 0.97, 95% CI = 0.89-1.06, p = 0.544) were not associated with depression onset during follow-up. During the same period, PGS for depression was not associated with overall sleep duration, short-sleep, or long-sleep. Polygenic predisposition to short-sleep was associated with depression onset over an average 8-year period. However, polygenic predisposition to depression was not associated with overall sleep duration, short-sleep or long-sleep, suggesting different mechanisms underlie the relationship between depression and the subsequent onset of suboptimal sleep durations in older adults.

Prevalence and determinants of depressive symptoms among community-dwelling older adults in China based on differences in living arrangements: a cross-sectional study

BACKGROUND

Older adults with different living arrangements may have different mental health statuses and different factors that influence their mental health. The aim of the present study is to investigate the prevalence and determinants of depressive symptoms among community-dwelling older adults in China based on differences in their living arrangements.

METHODS

Participants were 6,055 older adults from the 2015 China Health and Retirement Longitudinal Study. Depressive symptoms and their determinants were evaluated using the 10-item Center for Epidemiologic Studies Depression Scale and multivariate logistic regression analysis, respectively.

RESULTS

The prevalence of depressive symptoms among older adults living alone, as a couple, and with children was 47.8%, 33.2%, and 39.5%, respectively. The common risk factors for depressive symptoms were shorter sleep duration, poorer activities of daily living, and poorer self-rated health. Women, those with lower educational levels, and those suffering from chronic diseases had a higher risk of depressive symptoms among older adults living as a couple and those living with children. Smoking and participation in economic activities were also risk factors of depressive symptoms among older adults living with children and those living alone, respectively.

CONCLUSIONS

The findings suggest that older adults living as couples had the lowest prevalence of depressive symptoms, while those living alone had the highest prevalence of depressive symptoms. The determinants of depressive symptoms differed by living arrangement; hence, they should be considered in future interventions.

Adherence to continuous positive airway pressure treatment in a cohort of elderly adults with newly diagnosed obstructive sleep apnea

PURPOSE

To evaluate adherence to continuous positive airway pressure (CPAP) treatment in elderly patients newly diagnosed with obstructive sleep apnea syndrome (OSAS).

METHODS

Consecutive patients ≥ 70 years attending one of the participating centers, requiring CPAP treatment and agreeing to participate, were included. Mean hours of CPAP during the first 5 months of treatment defined adherence as CPAP ≥ 4 h/day on 70% of nights over a 30-day period.

RESULTS

From January 2014 to April 2019, 262 patients aged between 76.7 and 87.7 years (mean age, 82.6 years) were included and fully evaluated; 224 (85.5%) were adherent. Mean adherence time was 6.9 h in adherent patients, vs 2 h in non-adherent patients (p < 0.0001). Compared to non-adherent patients, adherent patients tended to have higher baseline AHI without reaching statistical significance (44.7 vs 39.5, p = 0.0913). They less frequently presented with dementia (3.7% vs 21.6%, p < 0.0001). The somnolence (ODSI and Epworth), nocturia, and depression (QD2A) scores of adherent patients improved significantly from baseline to the fifth month: ODSI decreased from 7 to 3.7 (p < 0.0001), Epworth from 8.7 to 6.2 (p < 0.0001), nocturia from 6.6 to 4.1 (p = 0.0015), and QD2A from 3.7 to 3 (p = 0.0025). Many more patients in the non-adherent group used nasal plugs than in the adherent group (14.7% vs 2.1%, p = 0.0006).

CONCLUSION

The present real-world study showed the ability of newly diagnosed elderly adults (including the very old) to adhere to CPAP therapy and the benefit of 5 months' well-conducted CPAP treatment.

REGISTRATION NUMBER

Not applicable.

Associations of sleep duration, daytime napping, and snoring with depression in rural China: a cross-sectional study

BACKGROUND

Most adult patients with depression complain about sleep symptoms, including insufficient and excessive sleep. However, previous studies investigating the impact of sleep duration on depression have yielded conflicting results. Therefore, this study aimed to analyse the link between depression and sleep duration, daytime napping, and snoring among rural Chinese adults.

METHODS

A cross-sectional study was conducted with 9104 individuals. Interviews were conducted with the participants regarding their sleep patterns and their daytime napping routines. The individuals were then assessed for depression using the Patient Health Questionnaire-9. The risk of depression was assessed using a multifactor binary logistic regression analysis. A generalized additive model was used to evaluate the nonlinear relationship between depression and sleep duration/nap time. Additionally, subgroup analysis was conducted to investigate the correlation between sleep duration, daytime napping, snoring, and depression.

RESULTS

Less than 6 h or more than 8 h of nighttime sleep, daytime napping for more than 1 h, and snoring were all significantly associated with an increased risk of depression. A U-shaped relationship was found between the duration of nighttime sleep and depression. In addition, we found that the nighttime duration of sleep, daytime naps, and snoring had a significant combined effect on the risk of depression. The subgroup analysis further revealed that lack of sleep at night significantly increased the risk of depression in all subgroups. However, snoring and excessive nighttime sleep and napping were only associated with the risk of depression in some subgroups.

CONCLUSIONS

Lack of nighttime sleep (short sleep duration), excessive sleep, and napping for more than one hour during the day were associated with a high risk of depression and had a combined effect with snoring.

Gut microbiota: Candidates for a novel strategy for ameliorating sleep disorders

The aim of this review was to evaluate the feasibility of treating sleep disorders using novel gut microbiota intervention strategies. Multiple factors can cause sleep disorders, including an imbalance in the gut microbiota. Studies of the microbiome-gut-brain axis have revealed bidirectional communication between the central nervous system and gut microbes, providing a more comprehensive understanding of mood and behavioral regulatory patterns. Changes in the gut microbiota and its metabolites can stimulate the endocrine, nervous, and immune systems, which regulate the release of neurotransmitters and alter the activity of the central nervous system, ultimately leading to sleep disorders. Here, we review the main factors affecting sleep, discuss possible pathways and molecular mechanisms of the interaction between sleep and the gut microbiota, and compare common gut microbiota intervention strategies aimed at improving sleep physiology.

Association between chronic diseases and depression in the middle-aged and older adult Chinese population-a seven-year follow-up study based on CHARLS

Background

With the aging of the Chinese population, the prevalence of depression and chronic diseases is continually growing among middle-aged and older adult people. This study aimed to investigate the association between chronic diseases and depression in this population.

Methods

Data from the China Health and Retirement Longitudinal Study (CHARLS) 2011-2018 longitudinal survey, a 7-years follow-up of 7,163 participants over 45 years old, with no depression at baseline (2011). The chronic disease status in our study was based on the self-report of the participants, and depression was defined by the 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10). The relationship between baseline chronic disease and depression was assessed by the Kaplan-Meier method and Cox proportional hazards regression models.

Results

After 7-years follow-up, 41.2% (2,951/7163, 95% CI:40.1, 42.3%) of the participants reported depression. The analysis showed that participants with chronic diseases at baseline had a higher risk of depression and that such risk increased significantly with the number of chronic diseases suffered (1 chronic disease: HR = 1.197; 2 chronic diseases: HR = 1.310; 3 and more chronic diseases: HR = 1.397). Diabetes or high blood sugar (HR = 1.185), kidney disease (HR = 1.252), stomach or other digestive diseases (HR = 1.128), and arthritis or rheumatism (HR = 1.221) all significantly increased the risk of depression in middle-aged and older adult Chinese.

Conclusion

The present study found that suffering from different degrees of chronic diseases increased the risk of depression in middle-aged and older adult people, and these findings may benefit preventing depression and improving the quality of mental health in this group.

Longitudinal Trends in Sleep and Related Factors Among South Korean Adults From 2009 to 2018

BACKGROUND AND PURPOSE

Excess or insufficient sleep, irregular sleep-wake patterns, and an extreme early or late chronotypes adversely impact physical and mental health. Changes in sleep characteristics should therefore be tracked, and factors that contribute to poor sleep should be identified. We investigated the changes in sleep patterns among South Korean adults during 2009-2018.

METHODS

Using data of a representative sample of South Korean adults from the 2009 (n=2,658, 48.5% males; age=44.5±15.0 years old [mean±standard deviation], age range=19-86 years) and 2018 (n=2,389, 49.1% males; age=47.9±16.3 years, age range=19-92 years) Korean Headache-Sleep Study, we explored changes in sleep timing, sleep duration, chronotype, and social jetlag (SJL). Logistic regression analysis was used to examine the association between average sleep duration and depression.

RESULTS

From 2009 to 2018, bedtimes were advanced by 10 and 25 min on workdays and free days, respectively. Meanwhile, wake-up times were advanced by 13 min and delayed by 12 min on workdays and free days, respectively. The average sleep duration significantly decreased from 7.45 h to 7.13 h. The prevalence of short sleep duration (<7 h) increased, whereas that of long sleep duration (≥8 h) decreased. A circadian preference toward eveningness and SJL increased. The prevalence of depression increased from 4.6% to 8.4%, and there were significant reverse J-shaped and U-shaped associations between average sleep duration and depression in 2009 and 2018, respectively.

CONCLUSIONS

Changes in sleep patterns and the association between sleep duration and depressive mood were determined from a representative sample of the South Korean adult population. Interventions to modify sleep behaviors might improve public health.

Assessment of Sleep Disturbances on Mental Health in Patients with Restless Legs Syndrome

Background and Objective

In our study, we aimed to evaluate the sleep disturbances of patients diagnosed with restless legs syndrome (RLS) regarding their mental health according to the severity of the disease.

Materials and Methods

The study included 166 patients diagnosed with RLS and 161 healthy controls in the same age interval as patients. Sleep disturbances of patients were defined with the "personal information form" (PIF) prepared by the researchers, while the mental health status of patients was defined with the "Brief Symptom Inventory" (BSI).

Results

All RLS patients had an increase in BSI subscale points, with a positive correlation to disease severity, and subscale points were significantly higher than the control group (p < 0.05). Those with the "frequent waking" problem had higher BSI subscale points compared to those without the problem (p<0.01 or 0.001). Those with "waking with respiratory distress," "daytime sleepiness," "very early waking," and "sleep disorder" problems had statistically significantly high BSI subscale points for all subscales, apart from hostility, compared to those without these problems (p<0.01 or 0.001).

Conclusion

It is considered that assessment of sleep disturbances causing disrupted quality of life and mood disorders is beneficial for the treatment of patients with RLS. Our study data appears to be related to the result that sleep disturbances and mental health disruptions might be associated with the disease severity among RLS patients.

Depressive symptoms and sleep in aged caregivers in a context of high social vulnerability

OBJECTIVE

To evaluate the relationship between depressive symptoms and sleep quality in aged caregivers of elderly people, in a context of high social vulnerability.

METHODS

A Cross-sectional study conducted between July 2019 and March 2020 with 65 aged caregivers of elderly people that were treated in five Family Heath Units from São Carlos, São Paulo. Instruments to characterize the caregivers and to evaluate the depressive symptoms and sleep quality were used in data collection. The Kruskal Wallis and Spearman Correlation tests were adopted.

RESULTS

73.9% of the caregivers presented poor sleep quality and 69.2% did not have depressive symptoms. In the caregivers with severe depressive symptoms, the mean sleep quality score was 11.4; in those with mild depressive symptoms, it was 9.0; and in those without depressive symptoms, it was 6.4. There was a direct and moderate correlation between sleep quality and depressive symptoms.

CONCLUSION

There is a relationship between depressive symptoms and sleep quality in aged caregivers.

The association between recreational physical activity and depression in the short sleep population: a cross-sectional study

Background

Short sleep is more common in the modern society. Recreational physical activity (RPA) like exercise brings both mental and physiological benefits to depression; paradoxically, lack of sleep is harmful. Evidence on the association between RPA and depression in the short sleep population is limited.

Methods

Participants with short sleep condition from the National health and Nutrition Examination Surveys (NHANES 2007-2018) were included in the present study. Short sleep condition was defined as ≤ 7 h per night. Sleep duration and RPA status were self-reported in NHANES by the Physical Activity Questionnaire using a 7-day recall method. Multivariable logistic regression was applied to evaluate the association between RPA and depression. Additionally, the non-linear relationship between RPA and depression was evaluated using the threshold effect analysis and restricted cubic spline.

Results

This cross-sectional study comprised 6,846 adults' data, and the weighted participants were 52,501,159. The weighted prevalence of depression was higher in females, which took up 65.85% of all depression patients. In fully adjusted models, sufficient volume of RPA was associated with lower depression risks, with OR (95% CI) =0.678 (0.520, 0.883). Further analysis revealed a U-shaped association between RPA and incident depression, and the inflection point was 640 MET-minutes/week. When RPA <640 MET-minutes/week, increased RPA was associated with lower risk of incident depression, with OR (95% CI) = 0.891 (0.834, 0.953). When RPA ≥ 640 MET-minutes/week, the benefits of RPA seemed to be not significant, with OR (95% CI) = 0.999 (0.990, 1.009).

Conclusion

Our findings observed associations between RPA condition and incident depression in the short sleep population. Moderate RPA was beneficial to maintain mental health and associated with lower incidence of depression for short sleepers, but excessive RPA might increase the risk of depression. For general short sleepers, keeping the RPA volume approximately 640 MET-minutes/week was beneficial to lower risks of depression. Gender difference should be considered as an important factor for further studies to examine these relationships and explore mechanisms.

Sleep quality, social rhythms, and depression among people living with HIV: a path analysis based on social zeitgeber theory

Background

People living with HIV frequently report sleep disturbances. The social zeitgeber theory, which proposes that stressful life events can interfere with sleep and even depression by destabilizing daily routines, provides new insights into identifying predictors of sleep disturbances and improving sleep in people living with HIV.

Objective

To explain the pathways affecting sleep quality in people living with HIV based on social zeitgeber theory.

Methods

A cross-sectional study was conducted to assess sleep quality, social rhythms, depression, social support, and coping styles from December 2020 to February 2021. The hypothetical model was tested and respecified by performing path analysis and a bias-corrected bootstrapping method using IBM AMOS 24 software. The report of this study followed the STROBE checklist.

Results

A total of 737 people living with HIV participated in the study. The final model presented a good fit (goodness of fit = 0.999, adjusted goodness of fit index = 0.984, normed fit index = 0.996, comparative fit index = 0.998, Tucker-Lewis index = 0.988, root mean square error of approximation = 0.030, chi-squared/degree of freedom = 1.646), explaining 32.3% of the variance in sleep quality among people living with HIV. Lower social rhythm stability was directly associated with poorer sleep quality, and depression mediated the relationship between social rhythms and sleep quality. Social support and coping styles affected sleep quality through social rhythms and depression.

Limitation

The cross-sectional study design precludes making assumptions about causality among factors.

Conclusion

This study validates and extends the applicability of the social zeitgeber theory in the HIV context. Social rhythms have direct and indirect effects on sleep. Social rhythms, sleep, and depression is not simply linked in a cascading sequence but is theoretically linked in a complex way. More studies are needed to explore the predictors of social rhythms, and interventions for stabilizing social rhythms have the potential to alleviate sleep disturbances and depression in people living with HIV.

Hypothetical interventions on risk factors for depression among middle-aged and older community-dwellers in China: An application of the parametric g-formula in a longitudinal study

BACKGROUND

Sleep disturbances, frailty, and body pain are widespread in middle-aged and older adults with depression, and have been identified as depression risk factors. However, there is a scarcity of research on the benefits of sleep improvement, frailty amelioration, and pain management on incident depression.

METHODS

A total of 8895 respondents aged above 45 years were derived from the China Health and Retirement Longitudinal Study (CHARLS) between 2011 and 2018. The parametric g-formula was used to estimate the 7-year risks of depression under independent hypothetical interventions on nighttime sleep duration (NSD), daytime napping duration (DND), perceived sleep quality (PSQ), frailty, and pain, as well as their various combinations.

RESULTS

The observed depression risk was 41.77 %. The independent intervention on frailty was the most effective in lowering incident depression, with a risk ratio (RR) of 0.61 (95 % CI: 0.57-0.64), followed by PSQ (RR: 0.75, 95 % CI: 0.73-0.78), pain (RR: 0.90, 95 % CI: 0.87-0.91), and NSD (RR: 0.96, 95 % CI: 0.93-0.98). In subgroup analysis, intervention on NSD was more effective in men, PSQ was more effective in middle-aged individuals, and frailty and pain were more effective in older persons. The combined intervention of NSD, PSQ, frailty, and pain lowered the risk the greatest (RR: 0.35, 95 % CI: 0.32-0.37).

LIMITATIONS

Generalizing our results to other populations should be possible if they have the same distribution of effect modifiers and interference patterns because of the calculation principle of the parametric g-formula.

CONCLUSIONS

Interventions for sleep disturbances, frailty, and body pain can minimize the risk of depression.

The Mediating Role of Depression in Association Between Total Sleep Time and Instrumental Activities of Daily Living in China

Objectives: This study aims to investigate the mediating role of depression and the moderating effect of gender in the relationship between total sleep time (TST) and instrumental activities of daily living (IADL) in middle-aged and elderly people (aged 45 or above).

Methods: The data used in this study is from the China Health and Retirement Longitudinal Study (CHARLS), including a total of 10,460 respondents. Associations between TST, IADL, depression, and gender were analyzed using logistic regression and Karlson, Holm, and Breen (KHB) methods.

Results: Short (OR = 1.42, 95% CI = 1.28–1.58 of ≤6 h) and long TST (OR = 1.16, 95% CI = 1.02–1.32 of 8–9 h; OR = 1.35, 95% CI = 1.19–1.54 of &gt;9 h) were both associated with IADL. The mediation effect analyses observed that depression explained 64.80% of the total effect of short TST (≤6 h) and IADL, but was insignificant in long TST (8–9 h and &gt;9 h). Meanwhile, gender has moderating effects on the mediation effect model.

Conclusion: The study suggests that health interventions that focused on the dimensions of TST and depression are crucial for preventing functional disability while accounting for gender differences.

COVID-19 Fear, Sleep Quality, Anxiety and Depression: A Moderated Mediation Model

The available literature demonstrates that COVID-19 fear (CV-19 F) may increase depressive symptoms in adolescents. However, few studies have explored the underlying mechanisms of this relationship. This study aimed to understand the role of anxiety and sleep quality in the association between CV-19 F and depression in Vietnamese adolescents. A sample of 685 adolescents, ages 15 to 19 (mean = 16.09, SD = 0.860), was recruited to participate in the study. The Pittsburgh Sleep Quality Index, the Depression Anxiety Stress Scales, and the Fear of COVID-19 Scale were completed by participants. Results indicated that the link between CV-19 F and depression was fully mediated by anxiety. Furthermore, this indirect relationship was moderated by sleep quality. Our findings provided new insights into the link between CV-19 F and depression as well as highlighted the potential value of reducing anxiety and improving sleep quality in the prevention of depression in adolescents with high levels of CV-19 F.

Functional connectivity between dorsal attention and default mode networks mediates subjective sleep duration and depression in young females

BACKGROUND

Depression prevails throughout the world. Young females are more likely to suffer from depression because of lack of sleep.

METHODS

We recruited 405 young female participants to assess their subjective sleep duration and self-rating depression. The resting-state magnetic resonance imaging (rs-fMRI) data were collected to identify the brain regions related to sleep duration and depression, and a mediating model was established among sleep duration, depression and functional connectivity (FC) of rs-fMRI.

RESULTS

Correlation analysis indicated that subjective sleep duration was negatively associated with self-rating depression in young females (r = -0.22, p < .001). The network connectivity between dorsal attention network (DAN) and default mode network (DMN) positively correlated with self-rating depression (r = 0.13, p < .05), and negatively correlated with subjective sleep duration (r = -0.14, p < .01). Furthermore, the mediation analysis revealed that the FC of DAN-DMN significantly mediated the effect of sleep duration on depression.

LIMITATIONS

The study was a cross-section design and the sleep duration of the participants was subjectively reported. Future studies should consider to track the participants longitudinally and to measure the objective sleep duration by actigraph or polysomnography.

CONCLUSIONS

The participants with less sleep duration are more prone to develop depression feelings. The FC of DAN-DMN mediated the effect of sleep duration on depression. Thus, the FC of DAN-DMN could be consider as a neural target to relieve depression by increasing sleep duration in young females.

Efficacy of Cognitive Behavioral Therapy for Insomnia for the Treatment of Child and Adolescent Anxiety and Depression: A Systematic Review From Randomized Controlled Trials

ABSTRACT

Cognitive behavioral therapy for insomnia (CBT-I) has shown promising results in the adult population. However, there is not enough evidence for children and adolescents. Hence, we evaluated the current evidence of CBT-I in the treatment of anxiety and depression in children and adolescents. Published randomized clinical trials published before June 2020 were searched from PubMed, Cochrane Library of database, clinicaltrials.gov, and Google Scholar. Out of seven included studies, six studies assessed the effect of CBT-I on depression, and five assessed the effect on anxiety. In this review, most studies in this review showed a strong effect of CBT-I on symptoms of depression. Although a positive effect of CBT-I on anxiety was noted, only a small number of studies have considered this management. These findings should be considered preliminary, and further large-scale studies are warranted to further explore this finding further.

The bidirectional association of 24-h activity rhythms and sleep with depressive symptoms in middle-aged and elderly persons

BACKGROUND

In older populations disturbed 24-h activity rhythms, poor sleep, and depressive symptoms are often lingering and co-morbid, making treatment difficult. To improve insights into these commonly co-occurring problems, we assessed the bidirectional association of sleep and 24-h activity rhythms with depressive symptoms in middle-aged and elderly persons.

METHODS

In 1734 participants (mean age: 62.3 ± 9.3 years, 55% women) from the prospective Rotterdam Study, 24-h activity rhythms and sleep were estimated with actigraphy (mean duration: 146 ± 19.6 h), sleep quality with the Pittsburgh Sleep Quality Index, and depressive symptoms with the Center for Epidemiological Studies Depression scale. Repeated measures were available for 947 participants (54%) over a median follow-up of 6 years (interquartile range = 5.6-6.3). Linear-mixed models were used to assess temporal associations of 24-h activity rhythms and sleep with depressive symptoms in both directions.

RESULTS

High 24-h activity rhythm fragmentation (IV) (B = 1.002, 95% confidence interval (CI) = 0.641-1.363), long time in bed (TIB) (B = 0.111, 95% CI = 0.053-0.169), low sleep efficiency (SE) (B = -0.015, 95% CI = -0.020 to -0.009), long sleep onset latency (SOL) (B = 0.009, 95% CI = 0.006-0.012), and low self-rated sleep quality (B = 0.112, 95% CI = 0.0992-0.124) at baseline were associated with increasing depressive symptoms over time. Conversely, more depressive symptoms at baseline were associated with an increasing 24-h activity rhythm fragmentation (B = 0.002, 95% CI = 0.001-0.003) and TIB (B = 0.009, 95% CI = 0.004-0.015), and a decreasing SE (B = -0.140, 95% CI = -0.196 to -0.084), SOL (B = 0.013, 95% CI = 0.008-0.018), and self-rated sleep quality (B = 0.193, 95% CI = 0.171-0.215) over time.

CONCLUSION

This study demonstrates a bidirectional association of 24-h activity rhythms, actigraphy-estimated sleep, and self-rated sleep quality with depressive symptoms over a time frame of multiple years in middle-aged and elderly persons.

Association between Nocturnal Sleep Duration and Insomnia symptoms with depressive symptoms among 44,900 Chinese Han adults aged 30-79 in Southwest China

BACKGROUND

Although there are several cross-sectional and prospective studies on the relationship between sleep duration /insomnia symptoms and depression symptoms, the results of these studies are still not conclusive, and few studies have further analyzed the association between sleep duration and depressive symptoms in adults by gender and age. Thus, this study aimed to investigate the relationship between nocturnal sleep duration and insomnia symptoms with depression symptoms, and further examine whether the association was impacted by age and gender in a large-scale Han Chinese population in southwest China.

METHODS

A cross-sectional study was performed that included 44,900 participants from 18 districts in southwest China from September 2018 to January 2019. The study comprised 42,242 individuals in the final analysis. Depressive symptoms were investigated using the PHQ-2 questionnaires. Multivariate logistic regression analysis was performed to investigate the relationship between nocturnal sleep duration and insomnia symptoms with depression symptoms as well as the influence of age and gender.

RESULTS

After adjusting for multiple variables, those with nocturnal sleep duration < 7 h had a higher odds ratio for depression (OR:1.47, 95%CI 1.31-1.65) compared to participants whose nocturnal sleep duration was in the range of 7-8 h. Notably, there is a higher association in those aged below 45 years (OR:1.91, 95%CI 1.52-2.41) and in female participants (OR:1.57, 95%CI 1.35-1.82). However, nocturnal sleep duration longer than 9 h was not associated with depression symptoms in either the whole population analysis or the subgroup analysis. Insomniacs had a higher odds ratio for depression(OR:1.87, 95%CI 1.84-2.36, respectively) compared to non-insomniacs. There is a higher association in those aged 45-60 years (OR:2.23, 95%CI 1.82-2.73) and in female participants (OR:2.17, 95%CI 1.84-2.56). Further subgroup analysis by age and gender at the same time showed the association between sleep deprivation and depression was highest among women aged below 45 years, while the association between insomnia and depression was the highest among men aged 45-59 years.

CONCLUSION

Short nocturnal sleep duration and insomnia symptoms were positively associated with the risk of depressive symptoms among Chinese Han adults aged 30-79 in Southwest China, especially the middle-aged population and females should be more concerned.

Multi-dimensional analyses of the associations between depression, nocturnal awakening and asthmatic outcomes

BACKGROUND

Depression plays an important role in the occurrence and development of asthma. Nocturnal awakening secondary to asthma is a crucial sign of the deterioration of asthmatic outcomes. This study plans to determine the associations between depression, nocturnal awakening and asthmatic outcomes by using multi-dimensional analyses.

METHODS

Study population came from the Adult Asthma Call-Back Survey 2013-2017. Multivariable regression analysis with binomial or Poisson models, dose-dependent analysis and mediation analysis were used to explore the associations between depression and nocturnal awakening with asthmatic episodes/attacks, emergency room (ER) and hospital visits.

RESULTS

18,684 physician-diagnosis asthmatics were included into this study. This population consisted of 31.4 % with nocturnal awakening and 37.6 % with depression. Multivariable binomial analyses suggested that nocturnal awakening and depression were positively associated with asthmatic episodes/attacks and ER visits. Dose-dependent analyses demonstrated that the increase of nocturnal awakening was positively associated with the increase of depression and three asthmatic outcomes. Asthmatics with depression had the higher prevalence (adjusted OR = 1.17, 95%CI: 1.08-1.27) and frequency (adjusted RR = 1.08, 95%CI: 1.07-1.10) of nocturnal awakening than those without depression. Mediation analyses suggested that clarification of verbiage denoted trivial effect of depression on the associations between nocturnal awakening with asthmatic outcomes, while nocturnal awakening mildly mediated these associations between depression with asthmatic episodes/attacks (15.26 %, 95%CI: 7.29 %-28.7 %) and ER visits (13.29 %, 95%CI: 5.33 %-44.12 %).

LIMITATION

The cross-sectional nature limited inferences on causality.

CONCLUSIONS

Our findings showed that depression and nocturnal awakening might affect asthmatic outcomes. Nocturnal awakening harbored the mediated effect in the correlations between depression and asthmatic outcomes.

Analysis of Sleep Quality in People With Dementia: A Preliminary Study

Background: Between 25% and 60% of subjects with dementia have shown sleep disturbances. Causes are diverse and seem to be related to factors such as aging, the presence of psychiatric diseases, or the consumption of drugs. This study aims to determine the influence of dementia on sleep quality and to analyze the factors that influence sleep quality in subjects ≥65 years. Methods: Thirty-one subjects were studied (15 living with dementia). PSQI was administered and statistical analysis compared the results among categories of other variables (age, gender, coffee consumption, drugs, BMI, psychiatric diseases). This study took place in Spain. Results: A prevalence of 46.7% of sleep disturbances was found in subjects with dementia. No significant differences were observed in the total score obtained in the PSQI between the dementia group (6.06 ± 3.78 points) and the group without dementia (7 ± 5.65 points). A significant inverse relationship was found between the sleep quality and the number of daily drugs and the presence of psychiatric diseases. Conclusion: Poor sleep quality affects people with dementia, however, we cannot affirm that dementia is the cause of it. Consumption of daily drugs and psychiatric diseases are factors that influence the sleep quality in subjects aged ≥65 years.

The role of maladaptive emotion regulation in the bidirectional relation between sleep and depression in college students during the COVID-19 pandemic

Background: Emotion regulation deficits are an outcome and risk factor for both insomnia and depression, suggesting that maladaptive emotion regulation might in part explain the bi-directional links between sleep and depression. The current study tests this hypothesis during the COVID-19 pandemic in emerging adult undergraduate students, a high-risk population for both depression and sleep disturbance.Methods: A sample of 154 undergraduate students completed a series of online questionnaires bi-weekly on sleep, depression, and emotion regulation strategies across eight weeks during the early days of the COVID-19 pandemic (April 2nd to June 27th, 2020).Results: Sleep disturbance and depression prospectively predicted one another across eight weeks, and both directions were mediated by maladaptive emotion regulation. However, sleep and depression failed to predict change in one another controlling for baseline measures, directly or via emotion regulation.Conclusions: The results suggest that maladaptive emotion regulation is a potential mechanism through which sleep disturbance and depression help maintain high levels of one another in college students during the COVID-19 pandemic. Therefore, emotion regulation deficits are potentially an important target for interventions to interrupt the sleep disturbance-depression cycle.

The relationship between unhealthy lifestyle patterns and depressive symptoms among residents in Beijing, China: A community-based cross-sectional study

Introduction

Depression is a prevalent mental disorder that has an irreversible impact on people's health status. Unhealthy lifestyles are modifiable and influence mental health significantly. The purpose of this study was to explore the impact of different unhealthy lifestyles and their patterns on depressive symptoms.

Methods

The data for this study were obtained from the 2017 Community Diagnostic survey in Daxing District, Beijing. It was a cross-sectional study that included 6,252 samples. The Patient Health Questionnaire version 9 was used to measure depressive symptoms, and the self-administered questionaires were used to investigate five unhealthy lifestyles, including sleep deprivation, the inadequate intake of fruits and vegetables, physical inactivity, smoking, and excessive alcohol consumption. Respondents were assigned 1 point for each of their unhealthy lifestyles, and their overall unhealthy lifestyle scores were calculated. The total scores of unhealthy lifestyles ranged from 0 to 5. Descriptive analyses and Firth's logistic regression model were used to analyze the relationship between unhealthy lifestyle and depression symptoms.

Results

It was found that 12.1% of the participants had depressive symptoms. The respondents whose unhealthy lifestyle scores were 2 (OR1.45, 95%CI:1.01 to 2.12), 3 (OR2.29, 95%CI:1.57 to 3.42), 4 (OR 3.04, 95%CI:1.96 to 4.76), or 5 (OR4.08, 95%CI:2.09 to 7.78) were more likely to experience depressive symptoms in comparison with those whose unhealthy lifestyle scores were 0, and the OR increased with the unhealthy lifestyle scores. When the participants had 3 or more unhealthy lifestyles at the same time, different combination patterns of unhealthy lifestyles showed a different effect on depression. The OR was 3.01 (95%CI:1.45 to 5.95) for the combination of sleep deprivation-insufficient intake of fruit and vegetables-excessive alcohol consumption, and was 2.89 (95%CI:1.52 to 5.25) for the combination of sleep deprivation-insufficient intake of fruit and vegetables-physical inactivity-excessive alcohol consumption.

Discussion

The co-existence of multiple unhealthy behavioral lifestyles are associated with depressive symptoms. Among the five unhealthy lifestyles, sleep deprivation and the inadequate intake of fruits and vegetables may have a greater impact on depression.

Sleep duration change from childhood to adulthood and adult depressive disorders in the Chinese population

BACKGROUND

Sleep deprivation may cause depressive disorders in both children and adults. However, the effects of sleep duration change from childhood to adulthood on adult depressive disorders are poorly documented. Using the China Family Panel Study (CFPS) data, we aimed to examine the association between sleep duration change from childhood to adulthood and adult depressive disorders in the Chinese population.

METHODS

Data were from 1172 children aged 10-15 years in 2010 who were followed up through 2018 based on the nationally representative and population-based CFPS. According to sleep duration in childhood and early adulthood, the sleep duration change was categorized into four groups: persistently insufficient sleep, sleep duration loss, sleep duration gain and persistently sufficient sleep.

RESULTS

After adjustment for potential covariates, compared with individuals with persistently sufficient sleep duration, those with sleep duration loss (OR = 1.98, 95% CI = 1.14-3.46) and persistently insufficient sleep (OR = 2.35, 95% CI = 1.43-3.88) had higher odds of depressive disorders in adulthood. In contrast, the odds of adult depressive disorders did not significantly increase in those with sleep duration gain (OR = 1.46, 95% CI = 0.88-2.41).

LIMITATIONS

Information on sleep duration was obtained through a questionnaire; the sample size of this study was not large; the generalizality of our findings to other populations should be caucious.

CONCLUSION

Persistently insufficient sleep duration and sleep duration loss from childhood to adulthood were associated with higher odds of adult depressive disorders, while those who were able to change their sleep duration from insufficient status to sufficient status didn't have an increased odds of adult depressive disorders.

Association between Sleep Duration and Symptoms of Depression Aged between 18 and 49: The Korea National Health and Nutrition Examination Survey (KNHANES Ⅶ) from 2016 to 2018

This study aimed to determine the association between symptoms of depression and sleep duration in a representative sample of the Korean population. Using national cross-sectional data from the seventh Korea National Health and Nutrition Examination Surveys (KNHANES-VII), 5461 adults aged 18−49 years were analyzed using logistic regression models. The proportions of participants with total daily sleep durations (24 h) of <6 h, 6−8 h, and ≥9 h were 26.2%, 60.6%, and 13.3%, respectively. The proportions of individuals with symptoms of depression in the <6 h, 6−8 h, and ≥9 h sleep duration groups were 37.4%, 46.3%, and 16.3%, respectively. The odds ratios (ORs) were significantly higher in the <6 h and ≥9 h sleep groups than in the 6−8 h sleep group. There was a significant association between short (<6 h/day) and long (≥9 h/day) sleep duration and symptoms of depression among the general Korean population. In particular, our findings suggest that short sleep (<6 h/day) is more associated with symptoms of depression than long sleep (≥9 h/day).

Longer depressive duration reduces sleep duration more: A longitudinal study in the middle-aged and elderly Chinese

BACKGROUND

Quantifying the effect of depression on sleep duration is of great importance to the diagnosis, control, prevention of sleep-related diseases and understanding related biological mechanisms. However, existing studies explored the effect without considering depressive duration, which may cause inaccurate results.

METHODS

Accessing the data from the China Health and Retirement Longitudinal Study in 2011, 2013, 2015 and 2018, we used the interval between two interviews with persistent depression status to approximate depressive duration. Five analysis subsamples with different depressive durations, i.e., 2, 3, 4, 5, 7 years, were obtained. The change amount of sleep duration between two interviews was used as the outcome variable. A multiple linear model was independently used to estimate the effect in each subsample, and meta-regression was used to test the trend. Subgroup analyses in terms of genders, ages and baseline sleep durations were performed.

RESULTS

On average, 2, 3, 4, 5, 7-years depressive durations significantly reduced sleep duration by 0.46, 0.57, 0.72, 0.75, 1.07 h (P < 0.001), respectively. Especially for the elderly, female, and participants with normal baseline sleep duration, the reduction was larger. Trend test showed that the variation trend was significant (P < 0.001). Similar results were found in the subgroup analyses.

LIMITATIONS

Sleep duration and depression are not measured by gold-standard methods.

CONCLUSIONS

Depression significantly reduces sleep duration, especially for the elderly, female, and people with normal baseline sleep duration. Longer depressive duration reduces sleep duration more. Such finding provides more detailed epidemiological evidence for depression-sleep relationship.

Sleep duration and incident and persistent depressive symptoms among a rural ageing population in South Africa

BACKGROUND

The aim of the study was to assess the relationship between sleep duration and incident depressive symptoms (IDS) and persistent depressive symptoms (PDS) using longitudinal data from South Africa.

METHODS

This longitudinal community study enrolled 3891 adults (≥40 years) from the "Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI)". Sleep duration was assessed by self-report at wave 1, and depressive symptoms were assessed using the Center for Epidemiological Studies Depression Scale at wave 1 and 2. Outcomes were incident and persistent depressive symptoms at wave 2. Multivariable logistic regression analysis was conducted to assess the associations between sleep duration at wave 1 and incident, and persistent depressive symptoms.

RESULTS

The prevalence of IDS was 25.6% and PDS 30.8%. The prevalence of very short, short, normal, and long sleep duration at baseline was 3.6%, 10.1%, 60.9% and 25.4%, respectively. In the fully adjusted model, long sleep duration was positively associated with IDS among men (AOR: 1.37, 95% CI: 1.02-1.84), but not among women (AOR: 0.91, 95% CI: 0.67-1.23). No models among both men and women showed a significant association between short sleep and IDS. Long sleep duration was associated with PDS (AOR: 2.04, 95% CI: 1.20-3.48) among men but not among women (AOR: 1.26, 95% CI: 0.76-2.11). Short sleep showed among both sexes no significant associations with PDS.

CONCLUSION

Long but not short sleep duration was independently associated with IDS and PDS among men but not among women.

Trajectories of 24-h movement guidelines from middle adolescence to adulthood on depression and suicidal ideation: a 22-year follow-up study

Background:

The 24-h movement guidelines for youth and adults recommend the specific duration of physical activity, sedentary time, and sleep duration to ensure optimal health, but little is known about its relationship to mental health indicators. The aim of the study was to explore the association between 24-h movement guidelines in adolescence and its trajectories from middle adolescence (12–17 years old) to adulthood (33–39 years old) with depression and suicidal ideation in adulthood.

Methods:

This prospective cohort study included individuals who participated in Waves I (1994–1995) and V (2016–2018) of the National Longitudinal Study of Adolescent Health (Add Health) in the United States. Physical activity, screen time and sleep duration were measured using questionnaires. Adults were categorized as having depression if they had a self-reported history of depression and/or prescription medication-use for depression in the previous four weeks. Suicidal ideation was assessed by a self-reported single question in both waves. Poisson regression analyses were used to estimate the incidence rate ratio (IRR) of depression and suicidal ideation at adulthood, according to meeting specific and combinations of 24-h movement guidelines at Wave I and its trajectories from adolescence to adulthood.

Results:

The study included 7,069 individuals (56.8% women). Adolescents who met physical activity guidelines and all three guidelines at middle adolescence had lower risk of depression (IRR = 0.84, 95%CI 0.72 to 0.98) and suicidal ideation (IRR = 0.74, 95%CI 0.55 to 0.99) at adulthood than those who did not meet any of these guidelines, respectively. Individuals who met the guidelines for screen time and all three guidelines in both adolescence and adulthood had lower risk of depression (screen time, IRR = 0.87, 95% CI 0.72 to 0.98; all three, IRR = 0.37, 95% CI 0.15 to 0.92) and suicidal ideation (screen time, IRR = 0.74, 95% CI 0.51 to 0.97; all three, IRR = 0.12, 95% CI 0.06 to 0.33) than those who never met the guidelines. Additionally, individuals who did not meet all three guidelines in adolescence but met the guidelines in adulthood had lower risk of suicidal ideation than those who never met the guidelines (IRR = 0.81, 95%CI 0.45 to 0.89).

Conclusion:

Our findings highlight the importance of promoting and maintaining adherence to the 24-h movement guidelines from middle adolescence to adulthood to prevent mental health problems. However, our findings must be interpreted carefully due to declared limitations, e.g., the self-reported assessments which are subject to sources of error and bias or that the dataset used to gauge meeting a guidelines (1994–1996) was made later (2016).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-022-01367-0.

Acculturation and depression are associated with short and long sleep duration among Mexican Americans in NHANES 2005-2018

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Length of time in the US was associated with long sleep duration.

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Individuals who speak majority English had higher odds of short sleep duration.

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Depression severity was linked to short and long sleep duration.

Acculturation and depression are linked to poor sleep quality and sleep problems that may explain ongoing health disparities for Hispanics/Latinos. We examined the associations of acculturation, depression, and sleep duration among the Mexican American population. We used a multinomial logistic regression model on cross-sectional data from the 2005–2018 National Health and Nutrition Examination Survey on 4,700 Mexican American adults aged ≥18 years old. The outcome of sleep duration was operationalized as short (≤6 h), optimal (7–8 h), and long (≥9 h). Acculturation was constructed using years living in the U.S. and language(s) spoken at home (majority Spanish, English and Spanish equally, majority English). Depression severity was assessed using the 9-item Patient Health Questionnaire. Covariates included gender, age, marital status, income, and U.S. citizenship. Speaking majority English (Adjusted Odds Ratio (AOR) = 1.23; 95% Confidence Interval (CI) = 1.00–1.52) and mild (AOR = 1.63; 95%CI = 1.32–2.01), moderate (AOR = 1.94; 95%CI = 1.43–2.63), and moderately severe/severe (AOR = 2.58; 95%CI = 1.72–3.88) levels of depression were significantly associated with short sleep duration. Living in the U.S. for ≥10 years (AOR = 1.61; 95%CI = 1.17–2.23) and moderately severe/severe depression (AOR = 2.30; 95%CI = 1.34–3.93) were significantly associated with long sleep duration. Our results provide additional evidence of a link between acculturation, depression, and short and long sleep duration among the Mexican American population. Understanding the sleep health of this population is important for informing future public health interventions and research. Additional investigation into the relationship between acculturation/depression and other sleep health measures among this population is warranted.