Jutta Backhaus

Test–retest reliability and validity of the Pittsburgh Sleep Quality Index in primary insomnia

OBJECTIVE Psychometric evaluation of the Pittsburgh Sleep Quality Index (PSQI) for primary insomnia. METHODS The study sample consisted of 80 patients with primary insomnia (DSM-IV). The length of the test-retest interval was either 2 days or several weeks. Validity analyses were calculated for PSQI data and data from sleep diaries, as well as polysomnography. To evaluate the specificity of the PSQI, insomnia patients were compared with a control group of 45 healthy subjects. RESULTS In primary insomnia patients, the overall PSQI global score correlation coefficient for test-retest reliability was .87. Validity analyses showed high correlations between PSQI and sleep log data and lower correlations with polysomnography data. A PSQI global score > 5 resulted in a sensitivity of 98.7 and specificity of 84.4 as a marker for sleep disturbances in insomnia patients versus controls. CONCLUSION The PSQI has a high test-retest reliability and a good validity for patients with primary insomnia.

Sleep disturbances are correlated with decreased morning awakening salivary cortisol

Morning and evening salivary cortisol levels were correlated with sleep parameters in 14 patients with primary insomnia and 15 healthy controls. Salivary cortisol was sampled immediately after awakening (T1), 15 min later (T2), and immediately before going to bed (T3) for 1 week at home. In parallel with this, subjects estimated parameters of sleep in a daily sleep log. Patients and controls were all non-smokers who did not differ regarding morning awakening time or bedtime. Cortisol after awakening was significantly decreased in primary insomnia. Salivary cortisol at the time of awakening correlated negatively with the subjective estimation of sleep quality, i.e. a low salivary cortisol level directly after awakening correlated with a higher frequency of nightly awakenings (r = -0.50), a diminished sleep quality (r = -0.34) and a decreased feeling of recovery after awakening (r = -0.35; all p < 0.05). Furthermore, awakening cortisol was negatively correlated with the Pittsburgh Sleep Quality Index (r = -0.43) and with a questionnaire on sleep-related cognitions with the subscales rumination in bed (r = -0.56 ) and focusing on sleep-related thoughts (r = -0.46; all p < 0.05).

Impaired declarative memory consolidation during sleep in patients with primary insomnia: Influence of sleep architecture and nocturnal cortisol release.

BACKGROUND A central cognitive function of sleep is to consolidate newly acquired memories for long-term storage. Here, we investigated whether the overnight consolidation of declarative memory in patients with chronic sleep disturbances is impaired, owing to less slow wave sleep (SWS) and an increased cortisol release. METHODS Polysomnographic recordings, serum cortisol concentrations, and overnight memory consolidation in 16 patients with primary insomnia were compared with those of 13 healthy control subjects. RESULTS Patients displayed distinctly less overnight consolidation of declarative memory (p < .05), which was significantly correlated with SWS in the control subjects (r = .69) but with rapid eye movement (REM) sleep in the patients (r = .56), who had a diminished amount of SWS (p < .05). Increased cortisol levels in the middle of the night were associated with impaired retrieval of declarative memory after sleep for both control subjects (r = -.52) and patients (r = -.46). CONCLUSIONS Primary insomnia is associated with a diminished sleep-related consolidation of declarative memory. Efficient overnight consolidation of declarative memory is associated with high amounts of SWS and low serum cortisol levels during the early part of the night. Where SWS is decreased, REM sleep might play a partly compensatory role in the consolidation of declarative memory.

Immediate as well as delayed post learning sleep but not wakefulness enhances declarative memory consolidation in children

While there is mounting evidence for the importance of sleep for declarative memory consolidation in adults, so far this issue has not been investigated in children despite considerable differences in sleep duration and sleep architecture between children and adults. Here, 27 children (aged between 9 and 12yr) were examined on two conditions: on the Sleep-Wake condition, subjects learned word pairs in the evening and delayed recall was tested first in the next morning after sleep and then again in the following evening after daytime wakefulness. On the Wake-Sleep condition, learning took place in the morning and delayed recall was tested in the evening of the same day and again in the next morning after sleep. In both conditions retention of declarative memory was significantly increased only after an interval of sleep that either followed immediately after learning (as in the Sleep-Wake condition) or that followed after daytime wakefulness (as in the Wake-Sleep condition), respectively. The results support the hypothesis that sleep plays an active role in declarative memory consolidation even if delayed and further show for the first time the importance of sleep for declarative memory consolidation during childhood.

Long-term effectiveness of a short-term cognitive-behavioral group treatment for primary insomnia.

Abstract The long-term effectiveness of a short-term cognitive-behavioral therapy was evaluated. The structured group treatment consisted of six weekly sessions and included progressive muscle relaxation, cognitive relaxation, modified stimulus control with bedtime restriction, thought stopping and cognitive restructuring. Twenty patients with chronic primary insomnia took part in the study. All patients were referred by physicians for diagnosis and therapy of insomnia. During a waiting period of six weeks prior to treatment, patients did not experience any change of their sleep parameters. After therapy, patients improved their total sleep time and sleep efficiency and reduced their sleep latency and negative sleep-related cognitions. Furthermore, depression scores decreased. Most of the treatment effects were significant at the end of the treatment and remained stable over the long-term follow-up, which was evaluated after a mean of almost three years (35±6.7 months). The subjective estimated total sleep time improved from 298±109 min prior to therapy to 351±54 min at the end of treatment, to 376±75 min at the 3-month follow-up, to 379±58 min at the 12-month follow-up and to 381±92 min. at the long-term follow-up.

Impact of Experimentally Induced Serotonin Deficiency by Tryptophan Depletion on Sleep EEG in Healthy Subjects

The tryptophan depletion test is a research strategy to investigate the functional consequences of decreasing the brain serotonin metabolism. Because serotonin is involved in sleep regulation and the regulation of affective states, we studied the acute polysomnographic effects of tryptophan depletion and expected to induce similar changes of sleep EEG as observed in depressed patients. A total of 12 healthy subjects (mean age 34 ± 3 years) had eight polysomnograms, divided in two blocks of 4 consecutive nights. After one adaptation and 1 baseline night, subjects received a low-protein diet on day 3 and 4 until midday. On day 4 at 18.00 h, they drank an amino acid mixture either devoid of tryptophan or containing 2.3 g of tryptophan (placebo control) in randomized and double-blind order, resulting in an 85% decrease (tryptophan depletion) and a 144% increase (placebo control) of serum tryptophan at 22.00 h. After tryptophan depletion but not placebo, significant effects on sleep EEG were observed in terms of decreased non-rapid eye movement (non-REM) stage 2, increase of wake %, and of rapid eye movement (REM) density compared with baseline. REM latency was not altered, however the first and second REM period interval were significantly shorter after tryptophan depletion. This study underlines the impact of the serotonergic system on sleep maintenance and on REM sleep.

How to preserve the antidepressive effect of sleep deprivation: A comparison of sleep phase advance and sleep phase delay

Abstract Total sleep deprivation (TSD) leads to an immediate amelioration of depressed mood in approximately 70 % of patients with the melancholic subtype of depression. The clinical utility of this procedure is limited, as the improvement usually subsides after the next night of sleep. In the present study, 40 depressed inpatients, being free of psychoactive medication for at least 7 days and who had responded to a TSD were then distributed (according to a matched-pair design) to a sleep phase advance (SPA = time in bed scheduled from 1700–2400 hrs) or a sleep phase delay (SPD = time in bed from 0200–0700 hrs) with a succeeding shift back (for one hour in the SPA group per day) respectively shift forward (for 30 minutes in the SPD group per day), until the initial sleep phase (2300–0600 hrs) was reached after seven days again. Based on previous observations it was hypothesized that a phase advance of the sleep period should prevent responders to TSD from relapsing. Whereas 75% of the TSD responders were stabilized by the phase advanced condition and did not relapse over a period of seven days, only 40% of the patients in the phase delayed condition did not relapse. Polysomnography during the course of the study gave no evidence that the unusual sleep schedules caused prolonged sleep deprivation. Abnormalities of REM sleep persisted both in the clinical responders and non-responders after the sleep wake manipulation. It is concluded that the clinical effectiveness of TSD can be significantly improved by combining TSD with a following phase advance of the sleep period.

A double-blind, randomized and placebo-controlled study on the polysomnographic withdrawal effects of zopiclone, zolpidem and triazolam in healthy subjects

Abstract Rebound effects after withdrawal from hypnotics are believed to trigger their chronic use and to enhance the risk of tolerance and dependence. It was the purpose of this study to investigate the acute polysomnographic withdrawal effects after a 4 week treatment with standard doses of the non-benzodiazepine hypnotics zopiclone and zolpidem compared with triazolam and placebo. Healthy male subjects between 22 and 35 years of age participated in a parallel study design. They received either zopiclone 7.5 mg (n=11), zolpidem 10 mg (n=11), triazolam 0.25 mg (n=10) or placebo (n=7) over 4 weeks in randomized and double-blind order. Sleep EEG was registered during 2 nights before treatment under placebo, on days 1, 27 and 28 of treatment and on days 29, 30, 41 and 42 under placebo. Total sleep time and sleep efficiency were lower in the 1st night after discontinuation of triazolam (p < 0.05, t-test). After withdrawal from zopiclone or zolpidem slight but not significant rebound effects concerning sleep continuity were observed. Self-rating scales showed minimal rebound insomnia after discontinuation of all three hypnotics. In the placebo group no changes of sleep parameters were observed. Assuming that rebound insomnia is part of a withdrawal reaction, this study indicates that the risks of tolerance and dependency are low when administering zopiclone or zolpidem at the recommended doses.

Short-term training increases diagnostic and treatment rate for insomnia in general practice

SummaryObjective To evaluate the effect of short-term training of general practitioners (GPs) on their diagnosis and treatment of chronic insomnia. Methods A three-step randomized control group design was used: After baseline evaluation (T1) a group of 9 GPs underwent a training of half a day, while 7 GPs served as a control group. The diagnostic and therapeutic handling of insomnia patients was reevaluated under obligatory use of a structured diagnostic questionnaire (T2) and under optional use of it (T3). Results From 16 general practices, 4,754 patients were included. The frequency rate of insomnia was 19.3 %. The lowest diagnostic and treatment rate was found for insomnia patients without comorbidity (15 % at T1). Systematic non-pharmacological treatment was not offered by the GPs. At T2 the diagnosis rate increased significantly from 37.9 % (T1) to 71.5 % (T2, p = 0.038). It fell back to lower levels at T3 but remained better than at T1. At T3 non-pharmacological treatments and referral to a sleep expert were advised more often. Conclusion Short-term training of GPs can significantly improve their diagnostic sensitivity and first-line treatment efforts against insomnia.

Urinary ethyl glucuronide (EtG) and ethyl sulphate (EtS) assessment: valuable tools to improve verification of abstention in alcohol-dependent patients during in-patient treatment and at follow-ups

AIMS The aims of this study were (i) to assess the effect of additional urinary ethyl glucuronide (EtG) and ethyl sulphate (EtS) assessment on diagnosed relapse rates in detoxified alcohol-dependent patients; and (ii) to compare dropout rates between EtG- and EtS-negative and -positive patients. DESIGN Two studies on detoxified alcohol-dependent patients. If patients had no indication of relapse they were asked for a urinary sample at discharge from in-patient treatment 3, 6 and 12 weeks after discharge (study 1) and 1, 3 and 6 weeks after discharge (study 2), respectively. SETTING Department of Psychiatry, University of Luebeck, Germany. PARTICIPANTS A total of 107 and 32 detoxified alcohol-dependent patients having participated in a 3-week in-patient motivation enhancement programme. MEASUREMENT Personal interviews, breathalyzer tests, assessment of urinary EtG and EtS with liquid chromatography-tandem mass spectrometry (LC-MS/MS analysis). FINDING Urinary EtG and EtS were always positive at the same time. In the first study 13.5% of the patients were already positive before being discharged from hospital. At the follow-ups 3, 6 and 12 weeks after discharge 12.2, 19.4 and 28.0%, respectively, of the patients coming to the follow-up and denying relapse were positive on urinary EtG and EtS. In the second study, of those patients showing up for follow-up after 1 week and denying relapse, EtG and EtS were positive in four cases (17.4%). Only one EtG- and EtS-positive relapser (3.1%) came to the next follow-ups. In both studies the rates of detected relapses were significantly higher for early follow-ups if urinary EtG and EtS results were considered additionally. Dropout rates until the next follow-up were significantly higher among positive than EtG- and EtS-negative patients. CONCLUSION Urinary EtG and EtS improve verification of abstinence in studies of alcohol-dependent patients.