The relationship between anxiety and depression

This article raises the question as to whether the constructs of anxiety and depression can be meaningfully separated. Through a review of the literature focusing on the mood states, trait models, and clinical syndromes of anxiety and depression, it is shown that the distinction may be more conceptually satisfying than empirically demonstrated. Implications of the equivocal empirical separation of anxiety and depression, and areas of research requiring further examination are defined, and a developmental model of anxiety and depression is suggested as a means of reconciling the confusion in the relationship between anxiety and depression.     

The effect of sleep fragmentation on sleep and performance in younger and older subjects

Groups of 12 normal 55-70-year-old and young adult subjects had their sleep experimentally disturbed at a rate of approximately 14 times per hour to determine the residual effects of moderate sleep disturbance and to determine any differential impact as a function of age. Normal age-related changes in sleep were seen on baseline and recovery nights. In the second night of sleep disturbance, the older subjects had a smaller increase in total awakenings than young adults. Older subjects had a slower increase in auditory arousal threshold as sleep disturbance progressed. The older subjects also tended to have less performance deterioration on morning testing than did young adults, and this difference was significant for numbers of correctly completed addition problems. These evidences led to the conclusion that, while both age groups were sensitive to moderate sleep disturbance, the older individuals appeared somewhat less sensitive than the young adults.     

Startle response potentiation to chemosensory anxiety signals in socially anxious individuals

The present study aimed to investigate whether withdrawal related behavior is activated in the context of chemosensory anxiety signals. Moreover, it was examined whether chemosensory perception of social stress is modulated by the degree of social anxiety. Axillary sweat was collected from students, awaiting an oral examination at the university (anxiety condition) and from the same students in a sport control condition. The chemosensory stimuli were presented to 32 participants (16 socially anxious) via an olfactometer during inhalation (duration = 3 s). 102 dB white noise bursts served as startle probes. During a single session only male or female axillary sweat was presented, therefore, all participants were tested in two separate sessions. Even though the chemosensory stimuli were perceived at the perceptual threshold level, participants could identify (forced choice) the emotion of the donors in the anxiety condition. In the context of chemosensory anxiety signals the acoustic startle reflex was significantly augmented as compared to startle responses obtained in the context of sport sweat (p = 0.002). This effect was more pronounced in socially anxious than in non-anxious participants. It is concluded that human motor systems automatically adapt to chemosensory stress signals. This adaptation is neither dependent on the gender of the odor donor nor on the gender of the perceiver, but is intensified in socially anxious participants.     

The interplay of sleep disturbance, anxiety, and depression in children

OBJECTIVE: To review and critically evaluate the association between sleep, anxiety, and depression in children and provide recommendations for future research. METHODS: A literature search was conducted using MEDLINE and PsychINFO computerized databases and bibliographies of relevant articles. RESULTS: A surprisingly small but growing research base exists on the relation between sleep disturbance, anxiety, and depression in pediatric populations. Existing research indicates a significant symptom overlap between anxiety, depression, and sleep. This overlap may complicate proper assessment and treatment of children with these disorders. CONCLUSIONS: Future research should ensure adequate assessment for symptoms of anxiety and depression when examining sleep disturbance in children. Likewise, research on anxiety and depression should include assessment for symptoms of disturbed sleep. Bridging the gap between these literatures should provide further insights into the etiologies of these disorders, increase symptom detection, and improve the clinical care of children and their families.     

The relationship between psychological and physiological measures of anxiety

The responses of 6 representative physiological parameters frequently assumed to be measures of anxiety along with a set of 4 psychological tests for measuring anxiety were obtained under naturalistic conditions from 25 patients hospitalized with a first myocardial infarction. A canonical correlational analysis failed to show any relationship between anxiety as assessed by the Taylor Manifest Anxiety Scale, Mood Adjective Check List, State-Trait Anxiety Inventory and Multiple Affect Adjective Check List psychological tests, and anxiety as assessed by the physiological indices of heart rate, systolic and diastolic blood pressures, epinephrine, norepinephrine and VMA. The intercorrelation matrix revealed a significant positive pattern of relationships among all 4 psychological tests, a non-significant, positive pattern of relationships among the physiological indices, and a non-significant, negative pattern of relationships between the psychological and physiological measures. The absence of mood-specific physiological measures for anxiety, as measured by the psychological tests, supports previous theory and investigation and points to the inadvisability of assuming that studies on anxiety that use diverse physiological and psychological measures yield results that may be compared as though they were assessing a common mood.     

The effects of total sleep deprivation, selective sleep interruption and sleep recovery on pain tolerance thresholds in healthy subjects

The aim of this study was to compare the effects of total sleep deprivation (TSD), rapid eye movement (REM) sleep and slow wave sleep (SWS) interruption and sleep recovery on mechanical and thermal pain sensitivity in healthy adults. Nine healthy male volunteers (age 26--43 years) were randomly assigned in this double blind and crossover study to undergo either REM sleep or SWS interruption. Periods of 6 consecutive laboratory nights separated by at least 2 weeks were designed as follows: N1 Adaptation night; N2 Baseline night; N3 Total sleep deprivation (40 h); N4 and N5 SWS or REM sleep interruption; N6 Recovery. Sleep was recorded and scored using standard methods. Tolerance thresholds to mechanical and thermal pain were assessed using an electronic pressure dolorimeter and a thermode operating on a Peltier principle. Relative to baseline levels, TSD decreased significantly mechanical pain thresholds (-8%). Both REM sleep and SWS interruption tended to decrease mechanical pain thresholds. Recovery sleep, after SWS interruption produced a significant increase in mechanical pain thresholds (+ 15%). Recovery sleep after REM sleep interruption did not significantly increase mechanical pain thresholds. No significant differences in thermal pain thresholds were detected between and within periods. In conclusion this experimental study in healthy adult volunteers has demonstrated an hyperalgesic effect related to 40 h TSD and an analgesic effect related to SWS recovery. The analgesic effect of SWS recovery is apparently greater than the analgesia induced by level I (World Health Organization) analgesic compounds in mechanical pain experiments in healthy volunteers.     

The relationship between subjective sleep estimation and objective sleep variables in depressed patients.

INTRODUCTION: To our knowledge there is no evidence in the literature about the relationship between subjective sleep estimation and objective sleep variables in depression. It is not known whether the subjective estimation of sleep quality and sleep duration is directly related to any objective sleep variable in depressed patients. METHODS: Thirty patients with major depression and 10 healthy subjects have been investigated in our sleep laboratory during 1 or 2 consecutive nights after 1 night for adaptation. Every subject, after final awakening in the laboratory, answered questions concerning the subjective feelings about sleep duration, number of awakenings and sleep depth. We compared the sleep estimation in both groups and calculated the correlation between objective and subjective sleep variables in depressed patients. RESULTS: The degree of a wrong sleep estimation in depressed patients is larger than in healthy subjects. Slow wave sleep (SWS) in depressed patients correlates positively with the subjective estimation of sleep duration. Eye movement density in REM sleep correlates with the subjective estimation of the number of awakenings. CONCLUSION: SWS in depression has a positive influence on the subjective feeling of sleep duration while phasic REM sleep activity has a negative influence.     

The relationship between sleep and mood in first-time and experienced mothers

Sleep disruption has been suggested to contribute to postpartum mood, but few studies have explored differences in this relationship between nulliparous and multiparous mothers. This study compared the interaction of sleep and mood as a function of parity. Thirty-five nulliparous and 34 multiparous mothers completed questionnaires on mood and sleep, and wore actigraphs for 7 days during the third trimester of pregnancy and within 2 weeks postpartum. Mood and objective sleep were better in multiparas than in nulliparas after delivery. However, other than a stronger association between subjective sleep and stress in nulliparous mothers, the relationship between sleep and mood did not differ significantly between the two groups. This suggests that parity might play only a limited role in the interaction between sleep and mood during the immediate postpartum period.     

The relationship between depression and anxiety: construction of a prototypical anxiety and depression scale.

The question of the relationship between anxiety and depression remains to be solved. The fact that clinical pictures show substantial overlap makes it difficult, using conventional instruments, to distinguish between the co-occurrence of anxiety and depression and overlap in definitions and measurement of the two syndromes. This calls for the construction of scales which exclude symptoms common to both syndromes and incorporate symptoms specific only to anxiety or only to depression; i.e. scales with maximum discriminant validity. This article describes the construction of two such scales based on PSE symptoms; a prototypical anxiety scale and a prototypical depression scale. In a sample of 134 non-psychotic psychiatric out-patients these scales show good reliability and validity, both as a measure of severity and as a screening device. Compared to the Hamilton anxiety and depression scales (HARS and HRSD), the correlation between the prototypical anxiety and depression scales is low.     

The relationship of EEG sleep to vital depression

Assessment of renal function was carried out in an unselected sample of patients with bipolar manic-depressive disorder receiving lithium for an average period of 4.5 years. Overall, glomerular filtration rate (GFR) fell within the established normal range based on sex and age, whereas measures of urinary concentrating ability were generally impaired. There was no relationship between duration of lithium treatment and either GFR or impairment of urinary concentrating ability. Moreover, there was no evidence of a progressive impairment of glomerular or tubular function in patients re-tested after 2 years. The results of this study confirm the safety of lithium administration in the majority of patients and emphasize the importance of careful clinical monitoring to avoid lithium intoxication.     

Effect of diazepam on anxiety,sexual motivation,and blood testosterone in anxious male mice

The effects of diazepam on anxious behavior, sexual motivation, and blood level of testosterone in the presence of a female were studied in male mice with elevated anxiety. Diazepam produced an anxiolytic effect in novel environment, but was ineffective during social contacts. The drug potentiated the primary sexual interest, but failed to correct exhaustion of sexual motivation. The drug produced no effect on blood testosterone. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 140, No. 12, pp. 608–613, December, 2005     

The relationship between chronically disrupted sleep and healthcare use

STUDY OBJECTIVES: To determine whether chronic sleep deprivation, sleep disruption, sleepiness, insomnia, and OSA are associated with increased healthcare use in a community-based population. DESIGN: Cross-sectional study. SETTING/PARTICIPANTS: 6440 Sleep Heart Health Study (SHHS) participants recruited from ongoing cohort studies. Interventions: N/A MEASUREMENTS: Polysomnography results (Apnea Hypopnea Index (AHI), percent of sleep time with oxyhemoglobin saturation below 90% (CT90), arousal index) as well as data on sleep related symptoms, medication use, and chronic illness. The indirect measure of predicted healthcare utilization was the modified Chronic Disease Score (CDS) calculated from medication data. RESULTS: After adjustment for age, gender, BMI and study site, subjects in the highest quartiles of AHI, CT90 and Epworth score had CDS that were 6%-9% higher than the lowest quartiles. The adjusted mean CDS for subjects with sleep apnea was similar to that for subjects with hypertension, chronic bronchitis or asthma and 18% greater than the mean CDS for subjects without sleep apnea. Among subjects who did not have significant sleep-disordered breathing, complaints of insomnia, sleepiness, fatigue, and not getting enough sleep were associated with increased CDS. CONCLUSIONS: This study demonstrated an association between subjective complaints of daytime sleepiness, inadequate sleep time, insomnia as well as objective measures of severity of SDB, and an indirect measure of healthcare utilization in a community-based sample. Though the percent increases in healthcare utilization observed were modest, the prevalence of these factors in the general population is high, and may therefore be associated with a substantial cost burden to the healthcare system.