Caterina Lombardo

Insomnia as a predictor of depression: A meta-analytic evaluation of longitudinal epidemiological studies

BACKGROUND In many patients with depression, symptoms of insomnia herald the onset of the disorder and may persist into remission or recovery, even after adequate treatment. Several studies have raised the question whether insomniac symptoms may constitute an independent clinical predictor of depression. This meta-analysis is aimed at evaluating quantitatively if insomnia constitutes a predictor of depression. METHODS PubMed, Medline, PsycInfo, and PsycArticles databases were searched from 1980 until 2010 to identify longitudinal epidemiological studies simultaneously investigating insomniac complaints and depressed psychopathology. Effects were summarized using the logarithms of the odds ratios for insomnia at baseline to predict depression at follow-up. Studies were pooled with both fixed- and random-effects meta-analytic models in order to evaluate the concordance. Heterogeneity test and sensitivity analysis were computed. RESULTS Twenty-one studies met inclusion criteria. Considering all studies together, heterogeneity was found. The random-effects model showed an overall odds ratio for insomnia to predict depression of 2.60 (confidence interval [CI]: 1.98-3.42). When the analysis was adjusted for outliers, the studies were not longer heterogeneous. The fixed-effects model showed an overall odds ratio of 2.10 (CI: 1.86-2.38). LIMITATIONS The main limit is that included studies did not always consider the role of other intervening variables. CONCLUSIONS Non-depressed people with insomnia have a twofold risk to develop depression, compared to people with no sleep difficulties. Thus, early treatment programs for insomnia might reduce the risk for developing depression in the general population and be considered a helpful general preventive strategy in the area of mental health care.

Sleep and emotions: A focus on insomnia

Insomnia disorder is defined as difficulties in initiating/maintaining sleep and/or non-restorative sleep accompanied by decreased daytime functioning, persisting for at least four weeks. For many patients suffering from depression and anxiety, insomnia is a pervasive problem. Many of the aetiological theories of insomnia postulate that heightened emotional reactivity contributes to the maintenance of symptoms. This review focuses on the role of emotional reactivity in insomnia, and how the relationship between insomnia and depression and anxiety may be mediated by emotional reactivity. Furthermore, studies investigating the valence of emotions in insomnia are reviewed. Overall, there is empirical evidence that dysfunctional emotional reactivity might mediate the interaction between cognitive and autonomic hyperarousal, thus contributing to the maintenance of insomnia. Moreover, dysfunctions in sleep-wake regulating neural circuitries seem to be able to reinforce emotional disturbances. It seems plausible that dysfunctional emotional reactivity modulates the relationship between insomnia and depression and anxiety. Considering the interaction between sleep and emotional valence, poor sleep quality seems to correlate with high negative and low positive emotions, both in clinical and subclinical samples. Good sleep seems to be associated with high positive emotions, but not necessarily with low negative emotions. This review underlines the need for future research on emotions in insomnia.

Psychophysiological reactivity to sleep-related emotional stimuli in primary insomnia.

The present study examined psychophysiological reactivity to emotional stimuli related and non-related to sleep in people with primary insomnia (PPI) and in good sleepers (GS). Twenty-one PPI and 18 GS were presented with five blocks of neutral, negative, positive, sleep-related negative and sleep-related positive pictures. During the presentation of the pictures, facial electromyography (EMG) of the corrugator and the zygomatic muscles, heart rate (HR) and cardiac vagal tone (CVT) were recorded. Subjective ratings of the stimuli were also collected. We found that only PPI exhibited greater inhibition of the corrugator activity in response to sleep-related positive stimuli compared to the other blocks of stimuli. Furthermore, PPI rated the sleep-related negative stimuli as more unpleasant and arousing and showed higher CVT in response to all stimuli as compared to GS. Results were interpreted as indicating that PPI exhibit craving for sleep-related positive stimuli, and also hyper-arousability in response to sleep-related negative stimuli, as compared to GS. Our results suggest that psychological treatment of insomnia could benefit by the inclusion of strategies dealing with emotional processes linked with sleep processes.

Insomnia Disorder is Associated with Increased Amygdala Reactivity to Insomnia-Related Stimuli

STUDY OBJECTIVES Alterations in emotional reactivity may play a key role in the pathophysiology of insomnia disorder (ID). However, only few supporting experimental data are currently available. We evaluated in a hypothesis-driven design whether patients with ID present altered amygdale responses to emotional stimuli related and unrelated to the experience of insomnia and, because of chronic hyperarousal, less habituation of amygdala responses. DESIGN Case-control study. SETTING Departments of Psychiatry and Psychotherapy and of Radiology of the University of Freiburg Medical Center. PARTICIPANTS There were 22 patients with ID (15 females; 7 males; age 40.7 ± 12.6 y) and 38 healthy good sleepers (HGS, 21 females; 17 males; age 39.6 ± 8.9 y). INTERVENTIONS N/A. MEASUREMENTS AND RESULTS In a functional magnetic resonance imaging session, five different blocks of pictures with varying emotional arousal, valence, and content (insomnia-relatedness) were presented. Pictures were presented twice to test for habituation processes. Results showed that patients with ID, compared to HGS, presented heightened amygdala responses to insomnia-related stimuli. Moreover, habituation of amygdale responses was observed only in HGS, but not in patients with ID who showed a mixed pattern of amygdala responses to the second presentation of the stimuli. CONCLUSIONS The results provide evidence for an insomnia-related emotional bias in patients with ID. Cognitive behavior treatment for ID could benefit from strategies dealing with the emotional charge associated with the disorder. Further studies should clarify the role of ID with respect to habituation of amygdala responses.

P300 amplitude in subjects with primary insomnia is modulated by their sleep quality

OBJECTIVE The hyperarousal hypothesis is evaluated while controlling the influence of the quality of sleep in the night preceding the evaluation. METHOD Eleven primary insomniacs and 11 healthy age matched controls participated to the study. Participants filled in 2 weeks of sleep logs and self-monitored their subjective tension the evening before and the morning after each night. Afterwards, subjects were called in to the Lab for a recording session of the P300 ERP (oddball paradigm) once after a night of bad sleep quality (N-) and once after a night of good sleep quality (N+). RESULTS The main result of the present study indicated that the P300 amplitude at Fz in insomniacs resulted higher following a N- and lower following a N+ with respect to controls. CONCLUSIONS This result suggests that cortical hyperarousal in primary insomniacs is not a stable individual characteristic, but is associated with the poor quality of their nocturnal sleep.

Psychometric properties of the Maslach Burnout Inventory for Human Services among Italian nurses: A test of alternative models

AIM The purpose of this study was to test the factor structure of an Italian version of the Maslach Burnout Inventory for Human Service employees. In addition we examined the reliability and construct validity of the scale. BACKGROUND There is increasing evidence that nurses are at risk of experiencing burnout. Despite the vast international use of the Maslach Burnout Inventory-Human Service Survey, its factor structure and reliability are not beyond question. METHOD In a sample of nurses (N = 1613) six alternative factor models of the instrument were tested using confirmatory factor analysis. Furthermore, we examined the invariance of the pattern of factor loadings of the model that better fitted the data across gender groups. To test construct validity, participants completed four subscales of Symptoms Check List 90-R. Internal consistency was evaluated computing Cronbachs alpha estimates of the scales. The study was conducted in 2007 and 2008 in Italy. RESULTS The factor analysis provided support for a 20-item version identifying the three original dimensions. The model was found to be factorially invariant between men and women. Correlations between the latent MBI-HSS dimensions and distress variables were in line with theoretical predictions. Reliability was supported by acceptable Cronbachs alpha indexes. CONCLUSION The Maslach Burnout Inventory-Human Service Survey has acceptable validity and reliability for measuring burnout among nurses, and can help healthcare managers to offer interventions to reduce burnout among nurses. Limitations of the study and suggestions for further research are highlighted.

Development and validation of a brief Occupational Coping Self-Efficacy Questionnaire for Nurses

AIM This paper is a report of a study to develop and test the psychometric properties of the Occupational Coping Self-Efficacy for Nurses Scale. BACKGROUND Coping self-efficacy beliefs are defined as self-appraisals of capabilities to cope with environmental demands. People with higher levels of coping self-efficacy beliefs tend to approach challenging situations in an active and persistent way, whereas those with lower levels of coping self-efficacy beliefs tend to direct greater energy to managing increasing emotional distress. METHOD In 2006, 1383 nurses completed the following measures: Occupational Coping Self-Efficacy Questionnaire for Nurses, Coping Inventory for Stressful Situations Short Form and Maslach Burnout Inventory. Based on a randomized split of the data, we conducted exploratory factor analysis on group 1 data (n = 691) and confirmatory factor analysis within the framework of structural equation modelling on group 2 data (n = 692). FINDINGS The exploratory results revealed two factors: Coping Self-Efficacy to cope with the occupational burden (Cronbach alpha = 0.77) and Coping Self-Efficacy to cope with the relational burden (alpha = 0.79). In the confirmatory group, the two-factor structure was tested against an alternative one-factor structure and confirmed as the best solution. Correlation patterns between the Occupational Coping Self-Efficacy for Nurses Scales, and both coping and burnout variables, supported the criterion-related validity of the Occupational Coping Self-Efficacy for Nurses dimensions. CONCLUSION Nurses can have two basic and distinct coping self-efficacy beliefs: beliefs about occupational burden and beliefs about relational difficulties in the workplace. Research is needed into how efficacy evaluations shift as a result of specific stress management interventions.

Occupational coping self-efficacy explains distress and well-being in nurses beyond psychosocial job characteristics.

Aim: The main purpose of the present study was to extend the Job Demand Control Support (JDCS) model analyzing the direct and interactive role of occupational coping self-efficacy (OCSE) beliefs. Background: OCSE refers to an individual’s beliefs about their ability to cope with occupational stressors. The interplay between occupational stressors, job resources, and self-efficacy beliefs is poorly investigated. The present research attempts to address this gap. Design: Cross-sectional survey. Method: Questionnaire data from 1479 nurses (65% response) were analyzed. Hierarchical regression analyses were used to test the direct and moderating role of OCSE in conjunction with job demands (i.e., time pressure), and two job resources: job control (i.e., decision latitude and skill discretion) and social support (i.e., supervisor support and coworker support) in predicting psychological distress and well-being. Results: Our findings indicated that high demands, low job control, and low social support additively predicted the distress/well-being outcomes (job satisfaction, emotional exhaustion, depersonalization, psychological distress, and somatic complaints). Beyond the main effects, no significant interactive effects of demands, control, and support were found. OCSE accounted for an additional 1–4% of the variance in the outcomes, after controlling for the JDCS variables. In addition, the results indicate that OCSE buffers the association between low job control and the distress dimensions emotional exhaustion, depersonalization, and psychological distress. Low control was detrimental only for nurses with low OCSE. Conclusion: Our results suggest expanding the JDCS model incorporating individual characteristics such as OCSE beliefs, for predicting psychological distress and well-being. Limitations of the study and practical implications are discussed.

Internal consistency, convergent validity and reliability of a brief Questionnaire on Disordered Eating (DEQ)

Clinical interviews are considered the gold standard for the evaluation of the specific psychopathology associated with eating disorders. However, there are situations in which brief but valid and reliable self-report questionnaires can be helpful. For this reason, we have developed a new questionnaire, called the DEQ (Disordered Eating Questionnaire), brief enough to be used in epidemiological screenings, that evaluates the frequency and intensity of disordered eating attitudes and behaviours within a time frame of three months and addresses face valid questions to the general population. The aim of this study was to evaluate the dimensionality, reliability and convergent validity of this questionnaire. The DEQ was filled in by Italian secondary school girls and boys, together with the Contour Drawing Rating Scale (CDRS) and with the Eating Attitudes Test (EAT-26). The results showed a single component that explain a portion of variance of around 36%. The reliability of the scale is highly satisfactory. The scale is also valid, since scores on the DEQ scale are significantly and highly correlated with body dissatisfaction, measured by the CDRS, with body mass inex (BMI) and with all the subscales of the EAT-26. As expected, there were gender differences, given that DEQ scores were higher in females than in males.

Are polysomnographic measures of sleep correlated to alexithymia?: A study on laboratory-adapted sleepers

OBJECTIVE Since recent findings have pointed to a correlation between alexithymia and measures of poor sleep quality during the first night of adaptation to a sleep laboratory, the aim of the current study was to assess the same relation in healthy laboratory-adapted sleepers. As a further measure of rapid eye movement (REM) sleep characteristics, REM density was also measured. METHODS Twenty-seven male subjects, without sleep or psychiatric disorders, filled out the 20-item Toronto Alexithymia Scale (TAS-20) and slept for two consecutive undisturbed nights. Polysomnography and REM density were measured in the postadaptation night. RESULTS Alexithymia scores did not correlate significantly with any polysomnographic variable or with REM density. Only the Externally Oriented Thinking (EOT) subscale showed a negative association with REM latency. Multiple regression on selected sleep measures as predictors confirmed these results. CONCLUSION Results do not extend to normal sleep the association previously found between alexithymia and a poor quality of sleep during the adaptation night in the sleep laboratory. The only polysomnographic measure showing an association, albeit little, with one facet of alexithymia was REM latency.