Strengths of associations between depressive symptoms and loneliness,perfectionistic concerns,risky alcohol use and physical activity across levels of sleep quality in Swedish university students: A cross-sectional study

Previous research shows that sleep quality may interact with some other predictors of depression, such that poor sleep could strengthen the association between these factors and depression. We aimed to determine the presence of statistical interactions between sleep quality and loneliness, risky alcohol use, perfectionistic concerns and/or physical inactivity in relation to depressive symptoms. Further, we aimed to describe the functional form of the statistical interactions and associations. We used a cross-sectional design and included 4262 Swedish university students. All measures were self-reported, sleep quality was measured with the Pittsburgh Sleep Quality Index, and depressive symptoms with the short-form Depression, Anxiety and Stress Scale. Regression models of increasing complexity (linear and non-linear, with and without interactions) were compared to determine the presence of associations and statistical interactions, and to explore the best functional form for these associations and interactions. Out-of-sample R² from repeated cross-validation was used to select the final models. We found that sleep quality was associated with depressive symptoms in all final models. Sleep quality showed a linear interaction with perfectionistic concerns in relation to depressive symptoms, such that perfectionistic concerns were more strongly associated with depressive symptoms when sleep quality was poor. Loneliness, risky alcohol use and physical inactivity were non-linearly associated with depressive symptoms but did not interact with sleep quality. We concluded that out of the four examined variables, only perfectionistic concerns interacted with sleep quality in relation to depressive symptoms. This interaction was weak and explained little of the overall variance in depressive symptoms.     

4～6年级小学生儿童虐待经历与抑郁情绪、睡眠质量的关系

目的:探讨儿童虐待经历与小学生抑郁情绪、睡眠质量的关系。方法:分层抽取重庆市主城3区的9所小学校(重点、普通及农民工小学各3所)的1523名在校4～6年级小学生。运用儿童受虐量表评定小学生的受虐待状况,量表总分中负的分值代表虐待;儿童抑郁自评量表(DSRSC)评定小学生的抑郁情绪,总分≥15分表示有抑郁症状;匹兹堡睡眠质量指数(PSQI)评定小学生的睡眠状况,量表总分>7分表示有睡眠质量问题。共收回有效问卷1417份。结果:小学生虐待、抑郁情绪、睡眠质量问题检出率分别为41.7%、23.2%、26.2%。受虐者的PSQI总分、入睡时间、睡眠时间、睡眠效率、日间功能障碍得分均较非受虐者高(均P<0.05);抑郁者的PSQI总分、入睡时间、睡眠效率得分较无抑郁者高(均P<0.05)。相关分析显示,PSQI总分和抑郁总分与躯体虐待、言语虐待的总分呈负相关(r=-0.06～-0.72,P<0.05);PSQI总分、入睡时间、睡眠效率得分与抑郁总分呈正相关(r=0.13～0.14,P<0.01)。结论:小学生受虐待、抑郁情绪、睡眠质量问题的检出率均较高,且受虐程度特别是躯体虐待、言语虐待程度越严重其情绪和睡眠质量也越差,值得学校和家长高度关注。     

Sleep quality of German soldiers before,during and after deployment in Afghanistan—a prospective study

In this prospective study, subjective sleep quality and excessive daytime sleepiness prior to, during and after deployment of German soldiers in Afghanistan were examined. Sleep quality (Pittsburgh Sleep Quality Index; PSQI) and daytime sleepiness (Epworth Sleepiness Scale; ESS) were assessed in 118 soldiers of the German army, who were deployed in Afghanistan for 6 months (deployment group: DG) and in 146 soldiers of a non‐deployed control group (CG) at baseline. Results of the longitudinal analysis are reported, based on assessments conducted prior to, during the deployment and afterwards in the DG, and in the CG in parallel. Sleep quality and daytime sleepiness in the DG were already impaired during the predeployment training phase and remained at that level during the deployment phase, which clearly indicates the need for more attention on sleep in young soldiers, already at this early stage. The percentage of impaired sleepers decreased significantly after deployment. Programmes to teach techniques to improve sleep and reduce stress should be implemented prior to deployment to reduce sleep difficulties and excessive daytime sleepiness and subsequent psychiatric disorders.     

Maternal depressive symptoms,sleep, and odds of spontaneous early birth: implications for racial inequities in birth outcomes

Study ObjectivesDelivery prior to full term affects 37% of US births, including ~400,000 preterm births (<37 weeks) and >1,000,000 early term births (37–38 weeks). Approximately 70% of cases of shortened gestation are spontaneous—without medically-indicated cause. Elucidation of modifiable behavioral factors would have considerable clinical impact.MethodsThis study examined the role of depressive symptoms and sleep quality in predicting the odds of spontaneous shortened gestation among 317 women (135 black, 182 white) who completed psychosocial assessment in mid-pregnancy.ResultsAdjusting for key covariates, black women had 1.89 times higher odds of spontaneous shortened gestation compared to White women (OR [95% CI] = 1.89 [1.01, 3.53], p = 0.046). Women who reported only poor subjective sleep quality (PSQI > 6) or only elevated depressive symptoms (CES-D ≥ 16) exhibited no statistically significant differences in odds of spontaneous shortened gestation compared to those with neither risk factor. However, women with comorbid poor sleep and depressive symptoms exhibited markedly higher odds of spontaneous shortened gestation than those with neither risk factor (39.2% versus 15.7% [OR (95% CI) = 2.69 (1.27, 5.70)], p = 0.01). A higher proportion of black women met criteria for both risk factors (23% of black women versus 11% of white women; p = 0.004), with a lower proportion experiencing neither risk factor (40.7% of black versus 64.3% of white women; p < 0.001).ConclusionsAdditive effects of poor subjective sleep quality and depressive symptoms were observed with markedly higher odds of spontaneous shortened gestation among women with both risk factors. Racial inequities in rates of comorbid exposure corresponded with inequities in shortened gestation. Future empirical studies and intervention efforts should consider the interactive effects of these commonly co-morbid exposures.     

Psychosocial work characteristics,sleep disturbances and risk of subsequent depressive symptoms: a study of time‐varying effect modification

Job strain and low social support at work are recognized risk factors for depression. However, people with poor sleep may represent a high‐risk group more likely to benefit from interventions against work stress. The present study examined whether the associations between these work stressors and depressive symptoms differed by strata of sleep disturbances (effect modification/effect moderation) considering repeat measures of work characteristics and sleep. The study was based on five biennial measurements of the Swedish Longitudinal Occupational Survey of Health, including 1537 respondents recurrently in paid work, from an originally representative sample of the Swedish working population. High work demands, low decision authority and low social support were measured waves 2 and 4, sleep disturbances (putative moderator/modifier) waves 1 and 3, and depressive symptoms (outcome) wave 5. Causal effect modification, whether the effect of working conditions differed by strata of sleep disturbances, was analysed by structural nested mean modelling estimated using a regression‐with‐residuals with inverse‐probability‐of‐treatment weighting approach. High demands and low social support, but not low decision authority, influenced subsequent depressive symptoms. The relationship between social support and depressive symptoms was not apparently modified by sleep disturbances. However, disturbed sleep wave 3 modified the effect of high demands wave 4 (coefficient 1.77, P < 0.05) on depressive symptoms wave 5. The results indicate that high job demands is a stronger risk factor for depressive symptoms in people with pre‐existing sleep disturbances, suggesting that targeted workplace interventions may be more effective when it comes to preventing negative effects of job demands.     

Patterns of sleep quality during and after postacute rehabilitation in older adults: a latent class analysis approach

Sleep quality is related to emotional, physical, psychological and cognitive functioning and functional independence in later life. After acute health events, older adults are likely to utilize postacute rehabilitation services to improve functioning and facilitate return to independent living. Patterns of how sleep changes with postacute rehabilitation, and predictors of such patterns, are unknown. The current investigation employed latent class analysis (LCA) methods to classify older adults (n = 233) into groups based on patterns of self‐reported sleep quality pre‐illness, during postacute rehabilitation and up to 1 year following postacute rehabilitation. Using LCA, older adults were grouped into (1) consistently good sleepers (46%), (2) good sleepers who transitioned into poor sleepers (34%), (3) consistently poor sleepers (14%) and (4) poor sleepers who transitioned into good sleepers (6%). In three planned analyses, pain was an independent predictor of membership in classes 1 or 2 (good pre‐illness sleep quality) versus classes 3 or 4 (poor pre‐illness sleep quality), and of membership in class 1 (consistently good sleep) versus class 2 (good sleep that transitioned to poor sleep). A lower Mini‐Mental State Examination score was a predictor of membership in class 1 versus class 2. There were no statistically significant predictors of membership in class 3 versus class 4. Demographics, comorbidities and depressive symptoms were not significant predictors of class membership. These findings have implications for identification of older adults at risk for developing poor sleep associated with changes in health and postacute rehabilitation. The findings also suggest that pain symptoms should be targeted to improve sleep during postacute rehabilitation.     

A hard day's night: a longitudinal study on the relationships among job demands and job control, sleep quality and fatigue

This prospective four-wave study examined (i) the causal direction of the longitudinal relations among job demands, job control, sleep quality and fatigue; and (ii) the effects of stability and change in demand–control history on the development of sleep quality and fatigue. Based on results of a four-wave complete panel study among 1163 Dutch employees, we found significant effects of job demands and job control on sleep quality and fatigue across a 1-year time lag, supporting the strain hypothesis (Demand–Control model; Karasek and Theorell, Basic Books, New York, 1990). No reversed or reciprocal causal patterns were detected. Furthermore, our results revealed that cumulative exposure to a high-strain work environment (characterized by high job demands and low job control) was associated with elevated levels of sleep-related complaints. Cumulative exposure to a low-strain work environment (i.e. low job demands and high job control) was associated with the highest sleep quality and lowest level of fatigue. Our results revealed further that changes in exposure history were related to changes in reported sleep quality and fatigue across time. As expected, a transition from a non-high-strain towards a high-strain job was associated with a significant increase in sleep-related complaints; conversely, a transition towards a non-high-strain job was not related to an improvement in sleep-related problems.