The reciprocal relationship between vigor and insomnia: a three-wave prospective study of employed adults

The thalamic clustering coefficient moderates the vigor-sleep quality relationship

Sleep disorders affect more than one-quarter of the world's population, resulting in reduced daytime productivity, impaired immune function, and an increased risk of cardiovascular disease. It is important to identify the physiological and psychological factors related to sleep for the prevention and treatment of sleep disorders. In this study, we correlated measurements of emotional state, sleep quality, and some brain neural activity parameters to better understand the brain and psychological factors related to sleep. Resting-state functional magnetic resonance imaging (rs-fMRI) of 116 healthy undergraduates were analyzed using graph theory to assess regional topological characteristics. Among these, the left thalamic cluster coefficient proved to be the ablest to reflect the characteristics of the sleep neural graph index. The Profile of Mood States (POMS) was used to measure vigor, and the Pittsburgh Sleep Quality Index (PSQI) to assess sleep quality. The results showed that the left thalamic clustering coefficient was negatively correlated with sleep quality and vigor. Further, the left thalamic clustering coefficient moderated the relationship between vigor and sleep quality. When the left thalamic clustering coefficient was very low, there was a significant positive correlation between vigor and sleep quality. However, when the left thalamic clustering coefficient was high, the correlation between vigor and sleep quality became insignificant. The relationship between vigor and sleep quality is heterogeneous. Analyzing the function of the left thalamic neural network could help understand the variation in the relationship between vigor and sleep quality in different populations. Such observations may help in the development of personalized interventions for sleep disorders.

Does engagement help to reduce insomnia when workers are emotionally exhausted?

Insomnia is one of the most common problems, affecting more than 35% of the world's population. To achieve a better understanding of this problem the focus of this research is to understand how emotional exhaustion at work may lead to insomnia. To help to combat it, we tested a mediation model including engagement factors. The sample was composed of 823 participants. 38.3% (315 subjects) were male and 61.7% (508 subjects) were female. Mean age was 42.65 years old (9.05 = SD). Main results showed that emotional exhaustion is directly and statistically significant related to insomnia. However, different engagement factors showed different weights in buffering this relationship. Emotional exhaustion showed a statistically significant impact on insomnia. Vigor and absorption helped to buffer the impact of emotional exhaustion over insomnia. Our study has some limitations. First, the sample was acquired by not aleatory processes. Another limitation is that our sample was composed of individuals with decision-making capacity. Lastly, our research is a transversal study. Future research should take these limitations into account and conduct longitudinal research with aleatory sampling procedures.

Sleep and Daily Positive Emotions – Is Heart Rate Variability a Mediator?

Abstract. Sleep quality is considered a basic dimension of emotional health. The psychophysiological mechanisms underlying the associations between sleep quality and positive emotions are still largely unknown, yet autonomic regulation may play a role. This study employed a two-day ecological momentary assessment methodology in a sample of young adults to investigate whether subjective sleep quality reported in the morning was associated with daily positive emotional experience and whether this association was mediated by heart rate variability (HRV), a measure of cardiac vagal tone. Sleep quality was assessed using an electronic sleep diary upon awakening, while resting HRV and positive emotions were inspected at random times throughout the day using photoplethysmography and an electronic diary, respectively. Relevant confounding variables such as smoking, alcohol intake, and physical exercise between each measurement were also assessed. The sample included 121 participants (64.8% females, Mage = 25.97 ± 5.32 years). After controlling for relevant confounders including health behaviors and psychiatric comorbidities, mediation analysis revealed that greater sleep quality positively predicted daily HRV (β = .289, p < .001) which, in turn, had a direct influence on positive emotions (β = .244, p = .006). Also, sleep quality directly predicted positive emotional experience (β = .272, p = .001). Lastly, the model showed an indirect effect between sleep quality and positive emotions via HRV (β = .071, 95% BCI [.011, .146]). Results support the view of HRV as a process variable linking sleep to positive emotions. Experimental data is needed to consolidate the present findings.

Effects of vigor at work and weekly physical activity on job stress and mental health

This study explores the role of personal resources, specifically vigor at work (a positive affect generated by the ongoing interactions in the workplace) and weekly physical activity (PA), in the stress-mental health relationship, given the positive relationships found between PA and levels of vigor experienced on health. Thus, we hypothesized that vigor at work would mediate the relationship between job stress and workers' mental health, whereas weekly PA would moderate the relationship between stress and vigor at work. Five hundred and twenty-seven workers completed self-report scales for stress, weekly PA, vigor at work, and mental health. The results showed that vigor at work was related to better mental health, whereas stress was related to high psychological problems and low vigor at work. The interaction between stress and weekly PA on vigor was significant, indicating a counterproductive effect of weekly PA. Specifically, the negative relationship between stress and vigor at work was greater when doing weekly PA. In this vein, high levels of weekly PA would not have a favorable impact when workers experience high levels of stress, consuming part of vigor at work and reducing the positive effect of vigor at work on mental health by coping with stress.

Optimism outweighs neuroticism and anxiety sensitivity to predict insomnia symptoms in women after surgery for breast cancer

PURPOSE

Insomnia symptoms are common among women who have undergone surgery for breast cancer. Personality traits are also believed to have an impact on sleep. However, there are no reports to address the effects of personality traits on sleep in women with breast cancer. This study examined the separate and competing roles of neuroticism, anxiety sensitivity, and optimism in predicting post-surgery insomnia symptoms.

METHODS

Women with breast cancer (n = 749) were enrolled the week prior to surgery and required to complete a demographic questionnaire, the Chinese version of Neuroticism subscale of NEO-Five Factor Inventory (CV-N-NEO-FFI), Anxiety Sensitivity Index-3 (CV-ASI-3), and Life Orientation Test-Revised (CV-LOT-R). Four weeks post-surgery, the Chinese version of Insomnia Severity Index (CV-ISI) was administered to evaluate insomnia symptoms.

RESULTS

Neuroticism (β = 0.317, p < 0.001), anxiety sensitivity (β = 0.220, p < 0.001), and optimism (β = - 0.332, p < 0.001) could predict post-surgery insomnia symptoms. When putting them together into one stepwise regression, optimism (β = - 0.215, p < 0.001) became the statistically most important predictor for insomnia symptoms. Optimism suppressed the predictions of insomnia symptoms provided by neuroticism (β = 0.114, p < 0.001) and anxiety sensitivity (β = 0.079, p < 0.001).

CONCLUSION

Neuroticism and anxiety sensitivity positively predicted insomnia, but optimism negatively predicted insomnia. In particular, optimism plays a more important role in post-surgery insomnia symptoms in women with breast cancer compared to neuroticism and anxiety sensitivity. Sleep intervention in women with breast cancer should focus on enhancing their optimism level.

Cultural Adaptation and Psychometric Properties of the Shirom-Melamed Vigor Measure (SMVM) With Workers in Spain

Shirom's proposal about engagement focuses on vigor. Under this approach, vigor is considered an affect that mediates the relationship between resources, behaviors, and attitudes related to psychological functioning and health. It is important for occupational health professionals to have adequate measures of this construct. The Shirom-Melamed vigor measure (SMVM) was developed to capture this sense of energy comprising three components (physical strength, emotional energy, and cognitive liveliness). In the absence of a Spanish version of the SMVM, our aim is to perform a cultural adaptation and to further analyze its psychometric properties. In Study 1, we culturally adapt the SMVM in Spanish samples. It incorporates a careful development of a three-step procedure according to the International Test Commission and qualitative analyses to ensure a consensus version. Twenty-six individuals were involved. In Study 2, the responses of 203 workers from different organizations show the validity and reliability of the instrument. Confirmatory factor analyses yield a model with three interrelated dimensions showing good fit indices. Furthermore, concurrent validity is demonstrated. Finally, we discuss the usefulness of the SMVM for occupational health professionals.