Validity of a short insomnia questionnaire: the SDQ

A test of the effects of acute sleep deprivation on general and specific self-reported anxiety and depressive symptoms: an experimental extension

Evidence indicates acute sleep deprivation affects negative mood states. The present study experimentally tested the effects of acute sleep deprivation on self-reported symptoms of state anxiety and depression as well as general distress among 88 physically and psychologically healthy adults. As hypothesized, the effects of acute sleep deprivation increased state anxiety and depression, as well as general distress, relative to a normal night of sleep control condition. Based on the tripartite model of anxiety and depression, these findings replicate and extend prior research by suggesting sleep deprivation among individuals without current Axis I disorders increases both state symptoms of anxiety and depression specifically, and general distress more broadly. Extending this work to clinical samples and prospectively testing mechanisms underlying these effects are important future directions in this area of research.

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.

An experimental investigation of the effects of acute sleep deprivation on panic-relevant biological challenge responding

Prospective research indicates sleep deprivation potentiates anxiety development, yet relatively little research has examined the effects of sleep deprivation in terms of specific types of anxiety. The current study tested the association between acute sleep deprivation and panic-relevant biological challenge responding among nonclinical participants. One hundred and two participants were randomly assigned to either an experimental (acute sleep deprivation) or control (no sleep deprivation) group. The day prior to and following the experimental (sleep) manipulation, participants completed a 5-minute 10% carbon dioxide-enriched air laboratory-based biological challenge. As predicted, sleep deprivation increased anxious and fearful responding to the challenge. Findings suggest sleep deprivation may be an important factor to consider in models of panic development. There are several areas in this general domain that warrant additional investigation.

Actigraphy in the assessment of insomnia: a quantitative approach

STUDY OBJECTIVE

The lack of quantitative criteria for identifying insomnia using actigraphy represents an unresolved limit for the use of actigraphy in a clinical setting. The current study was conducted to evaluate the most efficient actigraphic parameter in the assessment of insomnia and to suggest preliminary quantitative actigraphic criteria (QAC).

PARTICIPANTS AND MEASUREMENTS

Performing a retrospective study we recovered 408 actigraphic records from 3 sleep measure databases: 2 regarding insomnia patients (n = 126) and one normal sleepers (n = 282). We compared the 2 samples analyzing the following actigraphic sleep parameters: time in bed (TIB), sleep onset latency (SOL), total sleep time (TST), wake after sleep onset (WASO), sleep efficiency percentage (SE%), number of awakenings longer than 5 minutes (NA > 5) and mean motor activity (MA). Moreover, a linear discriminant function (LDF) was developed to identify and combine the most useful actigraphic sleep parameters to separate insomnia patients from normal sleepers. Using Youden index we calculated the preliminary QAC for each actigraphic sleep parameter and for LDF. Receiver operator characteristic (ROC) curves for classifying the accuracy of QAC were performed.

RESULTS

All sleep parameters recorded by actigraphy significantly differentiated the 2 groups, except TIB. An LDF analysis showed that the most useful combination of actigraphic sleep parameters to assess insomnia was TST, SOL, and NA > 5, which obtained the best ROC and the best balance between positive and negative predictive values compared to any single actigraphic parameter.

CONCLUSION

Actigraphy provided a satisfactory objective measurement of sleep quality in insomnia patients. The combination of TST, SOL, and NA > 5 proved the best way to assess insomnia using actigraphy. Acknowledging that the lack of a technological standard and some methodological limitations prevent us generalizing our results, we recommend additional studies on larger populations using different actigraph models.

A new scale for measuring insomnia: the Bergen Insomnia Scale

A new scale for the measurement of insomnia, the Bergen Insomnia Scale, was constructed on the basis of current formal and clinical diagnostic criteria for insomnia. There are six items, of which the first three pertain to sleep onset, maintenance, and early morning wakening insomnia, respectively. The last three items refer to not feeling adequately rested, experiencing daytime impairment, and being dissatisfied with current sleep. This scale was validated in three samples, 320 students, 2645 community persons, and 225 patients. Cronbach alphas in the three samples were .79, .87, and .80, respectively. The 2-wk. test-retest reliability for students was .77. In the student and the patient samples, a two-factor solution was found, nocturnal symptoms and daytime symptoms, but in the community sample, a one-factor solution was found. The Bergen Insomnia Scale discriminated well between the patient sample and the other two. In all three, values of convergent and discriminative validity in relation to other self-report measures were good, as well as in relation to polysomnographic data for patients. It is concluded that the Bergen Insomnia Scale has good psychometric properties. It is one of very few insomnia scales which provide normative data for comparisons and which has been validated against subjective as well as polysomnographic data.

Using Rasch analysis to validate the revised PSQI to assess sleep disorders in Taiwan's hi-tech workers

The Pittsburgh Sleep Quality Index (PSQI) is an effective instrument for measuring the quality of sleep in older adults. In this study, we used Rasch analysis to validate the items of the revised PSQI (SC_PSQI) that contribute to a single construct. A total of 3,742 workers agreed to participate in this study. Both the appropriateness of the scoring rubrics and the unidimensionality of the SC_PSQI scale were investigated. All nine items fit the model's expectations rather well. These results indicate that the SC_PSQI with a 0 to 2 scoring scale can be used as a unidimensionality to assess sleep quality.

Sleep Complaints in Italian Olympic and Recreational Athletes

The aim of the study was to evaluate sleep complaints in two groups of subjects all involved in sport but differing with respect to their level of commitment and weekly amount of practice. The first group was composed of 103 elite Italian Olympic athletes. The second group consisted of 198 recreational athletes, divided into two subsets on the basis of their self-reported habitual weekly amount of exercise. Subjects were requested to complete a short questionnaire (SDQ) assessing the presence and intensity of sleep disorders according to DSM-IV-TR and ICSD-2 criteria. A logistic regression was carried out to assess any differences in sleep disorders between Olympic and recreational athletes. The Olympic athletes were more likely to show no sleep disorders and less likely to show chronic or occasional sleep disorders as compared to both the other groups of athletes. No differences were found between the two subsets of recreational athletes.