Sleep and Depressive Symptoms in the Morningness/Eveningness-Suicidal Ideation Relationship Depend on School Shift in Mexican Adolescents.

The aim was to analyze the morningness/eveningness (M/E) effect on suicidal ideation through sleep and depressive symptoms mediators with school shift (i.e., morning and afternoon) as moderator. In this study, 586 Mexican adolescents, with a mean age of 16.31 ± 0.92, from a public high school in a double-shift school system (298 from the morning shift and 288 from the afternoon shift) participated. Measurements of sleep, morningness/eveningness (circadian preference), depressive symptomology, and suicidal ideation were completed. Adolescents in the afternoon shift reported a later rise time, bedtime, greater time in bed sleep length, and less social jet lag than in the morning shift. Considering the moderated-mediated analysis, circadian preference and suicidal ideation were mediated by both depressive symptoms and school day's sleep length in the morning shift. In the afternoon shift, no mediation effect was significant. When weekend sleep length was considered in the model, only depressive symptoms had a mediating effect between circadian preference and suicidal ideation in the morning shift; no significant mediating effect was found on the afternoon shift. The results suggest that an afternoon school schedule may act as a protective factor for the adolescent's mental health and may represent a viable option for future interventions.

The Parent's Chronotype and Child's Sleeping Quality in Association with Relationship Satisfaction.

The prospective Ulm-SPATZ study was investigated to assess the role of child sleeping quality between 4 to 6 years of age in affecting a partner's sleeping and relationship satisfaction within a couple. The study was conducted using a triadic approach in which the child was included in the Actor-Partner-Interdependence Model (APIM). Sleeping quality of the child was determined by using the German version of the children's sleep habits questionnaire, sleeping features of the parents were assessed by using the Munich chronotype questionnaire, and the partner relationship assessment was performed by employing the German version of the parenting stress index questionnaire. In 211 German triads, we observed that sleeping characteristics and partner relationship scores at different child ages are consistent for both men and women. Higher and statistically significant sleep duration, time spent in bed, the midpoint of sleep, time getting out of bed, and sleep onset in women compared to men during the working days were observed. The APIM analyses showed a significant direct effect of child sleep quality on the partner relationship satisfaction. In women, a mediated effect of child sleep quality acted through sleep duration and time spent in bed on the partner relationship satisfaction score during both free and working days. In men, low child sleep quality was found to be associated with increased sleep onset during both free and working days. Child sleep quality influences relationship satisfaction mostly in mothers, likely because of their higher involvement in childcare during working days. Distress in the couple could be counteracted by a major involvement of the fathers in child management.

Circadian preference and relationship satisfaction among three types of couples.

Mate selection is part of a growing interest in the study of processes by which couples are established, consolidated and/or separated. Similarity in psychological traits has been related to the well-being of couples, but given the possible effect of temporal convergence, it is necessary to control for the relationship length and whether or not both members of the couple live together. The aim of this study was to analyse the association between Morningness/Eveningness (M/E) similarity and relationship satisfaction in young-dating-non-cohabiting, young-married-cohabiting and old-married-cohabiting couples. Participants included 357 heterosexual couples (357 women and 357 men) with a mean age of 38.42 years old (SD = 13.11; age range between 19 and 69) who completed M/E (Composite Scale of Morningness) and relationship satisfaction measures (Comprehensive Marital Satisfaction Scale). Similarity in M/E was positively related to greater relationship satisfaction in both young cohabiting and non-cohabiting couples. In women, their own M/E was related to their own relationship satisfaction, whereas the level of relationship satisfaction in men was related to their partner's M/E. This relationship was observed in young-married-cohabiting couples. M/E similarity may operate differently as a function of the relationship stage.

Age and Sex Differences in Morningness/Eveningness Along the Life Span: A Cross-Sectional Study in Spain.

Work psychology has noted the importance of considering the temporal dimension of behavior in organizations. Given that society widely operates on a 24-hr schedule, it is important to know how circadian typologies are distributed in the general population. In this study, diurnal preference was analyzed among 4,175 Spanish participants (61.3% women), 12-59 years old, who completed the Composite Scale of Morningness (Smith, Reilly, & Midkiff, 1989). Several measurement models of the CSM were analyzed using exploratory structural equation modeling and confirmatory factor analysis. The bifactor model showed the best fit, with a general factor (morningness/eveningness) and three subfactors (morningness, morning affect, and time of retiring). The age and sex factorial invariance of the bifactor model were tenable at the latent variance-covariance level. Next, age and sex differences analysis indicated a progressive increase in morningness with age, but over 40 years old, men were more morningness oriented than women were. These results indicate that morningness/eveningness can be considered a multidimensional construct and that psychosocial factors must be considered when estimating the prevalence of morningness/eveningness in different populations or countries.