Annie Vallières

Validation of the Insomnia Severity Index as an outcome measure for insomnia research

Background: Insomnia is a prevalent health complaint that is often difficult to evaluate reliably. There is an important need for brief and valid assessment tools to assist practitioners in the clinical evaluation of insomnia complaints.Objective: This paper reports on the clinical validation of the Insomnia Severity Index (ISI) as a brief screening measure of insomnia and as an outcome measure in treatment research. The psychometric properties (internal consistency, concurrent validity, factor structure) of the ISI were evaluated in two samples of insomnia patients.Methods: The first study examined the internal consistency and concurrent validity of the ISI in 145 patients evaluated for insomnia at a sleep disorders clinic. Data from the ISI were compared to those of a sleep diary measure. In the second study, the concurrent validity of the ISI was evaluated in a sample of 78 older patients who participated in a randomized-controlled trial of behavioral and pharmacological therapies for insomnia. Change scores on the ISI over time were compared with those obtained from sleep diaries and polysomnography. Comparisons were also made between ISI scores obtained from patients, significant others, and clinicians.Results: The results of Study 1 showed that the ISI has adequate internal consistency and is a reliable self-report measure to evaluate perceived sleep difficulties. The results from Study 2 also indicated that the ISI is a valid and sensitive measure to detect changes in perceived sleep difficulties with treatment. In addition, there is a close convergence between scores obtained from the ISI patients version and those from the clinicians and significant others versions.Conclusions: The present findings indicate that the ISI is a reliable and valid instrument to quantify perceived insomnia severity. The ISI is likely to be a clinically useful tool as a screening device or as an outcome measure in insomnia treatment research.

Cognitive behavioral therapy, singly and combined with medication, for persistent insomnia: a randomized controlled trial.

CONTEXT Cognitive behavioral therapy (CBT) and hypnotic medications are efficacious for short-term treatment of insomnia, but few patients achieve complete remission with any single treatment. It is unclear whether combined or maintenance therapies would enhance outcome. OBJECTIVES To evaluate the added value of medication over CBT alone for acute treatment of insomnia and the effects of maintenance therapies on long-term outcome. DESIGN, SETTING, AND PATIENTS Prospective, randomized controlled trial involving 2-stage therapy for 160 adults with persistent insomnia treated at a university hospital sleep center in Canada between January 2002 and April 2005. INTERVENTIONS Participants received CBT alone or CBT plus 10 mg/d (taken at bedtime) of zolpidem for an initial 6-week therapy, followed by extended 6-month therapy. Patients initially treated with CBT attended monthly maintenance CBT for 6 months or received no additional treatment and those initially treated with combined therapy (CBT plus 10 mg/d of zolpidem) continued with CBT plus intermittent use of zolpidem or CBT only. MAIN OUTCOME MEASURES Sleep onset latency, time awake after sleep onset, total sleep time, and sleep efficiency derived from daily diaries (primary outcomes); treatment response and remission rates derived from the Insomnia Severity Index (secondary outcomes). RESULTS Cognitive behavioral therapy used singly or in combination with zolpidem produced significant improvements in sleep latency, time awake after sleep onset, and sleep efficiency during initial therapy (all P<.001); a larger increase of sleep time was obtained with the combined approach (P = .04). Both CBT alone and CBT plus zolpidem produced similar rates of treatment responders (60% [45/75] vs 61% [45/74], respectively; P = .84) and treatment remissions (39% [29/75] vs 44% [33/74], respectively; P = .52) with the 6-week acute treatment, but combined therapy produced a higher remission rate compared with CBT alone during the 6-month extended therapy phase and the 6-month follow-up period (56% [43/74 and 32/59] vs 43% [34/75 and 28/68]; P = .05). The best long-term outcome was obtained with patients treated with combined therapy initially, followed by CBT alone, as evidenced by higher remission rates at the 6-month follow-up compared with patients who continued to take zolpidem during extended therapy (68% [20/30] vs 42% [12/29]; P = .04). CONCLUSION In patients with persistent insomnia, the addition of medication to CBT produced added benefits during acute therapy, but long-term outcome was optimized when medication is discontinued during maintenance CBT. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00042146.

Precipitating factors of insomnia

Insomnia is a prevalent health complaint whose onset is precipitated by a variety of factors. There is an important need to identify and describe these factors to improve our understanding of risk factors and the natural history of insomnia. This article is aimed at identifying and describing the types of precipitating factors related to the onset of insomnia. A total of 345 patients evaluated for insomnia at a sleep-disorders clinic completed a sleep survey and underwent a semistructured clinical interview. As part of the evaluation, the specific precipitating events related to the onset of insomnia were identified. Subsequently, these factors were categorized (work-school, family, physical or psychological health, or indeterminate), and their affective valence (negative, positive, or indeterminate) was coded. The most common precipitating factors of insomnia were related to family, health, and work-school events. Sixty-five percent of precipitating events had a negative valence. These events differed with the age of onset of insomnia but not with the gender of participants. These findings are useful to identify potential risk factors for insomnia and improve our understanding of the natural history of insomnia.

Variability and predictability in sleep patterns of chronic insomniacs

Sleep of chronic insomniacs is often characterized by extensive night‐to‐night variability. To date, no study has examined this variability with long series of daily sleep data. The present study examined night‐to‐night variability with a sample of 106 participants meeting DSM‐IV diagnostic criteria for persistent primary insomnia. Participants completed daily sleep diaries for an average of 31 days (range: 18–56). Sleep efficiency, sleep onset latency and wake after sleep onset were derived from this measure. Despite evidence of extensive night variability, results showed that sleep patterns could be classified in three clusters. The first one was characterized by a high probability of having poor sleep, the second one by a low and decreasing probability, and the third one by a constant median probability of having a poor sleep, which is an unpredictable sleep pattern. In the first cluster, poor sleep was expected each night for patients with a predominance mixed insomnia including the three insomnia subtypes. In the second cluster, patients presented moderate insomnia, sleep‐onset latency below the threshold level and a predominance of sleep‐maintenance insomnia. In the third pattern, poor nights seemed unpredictable for patients with moderate to severe insomnia associated with the lowest proportion of sleep‐maintenance insomnia. Overall, sleep was predictable for about two‐thirds of individuals, whereas it was unpredictable for about one‐third. These findings confirm the presence of extensive variability in the sleep of chronic insomniacs and that poor sleep may be predictable for some of them. Additional research is needed to characterize those sleep patterns in terms of clinical features and temporal course.

Functional and dysfunctional perfectionists : are they different on compulsive-like behaviors?

Both perfectionism and excessive responsibility have been linked to obsessive compulsive disorder (OCD). Up to now however, a greater number of studies have focused on the role of responsibility. The present study compared compulsive-like behavior of people with different styles of perfectionism. Sixteen functional perfectionists (FP) and 16 dysfunctional perfectionists (DP) were compared on three different tasks in order to explore OC type behavior such as doubting, checking and intrusions. Results show that DP participants, compared to FP participants, scored higher on an OC behavior scale, took significantly more time to complete a precision task and precipitated their decision when confronted with ambiguity. The two groups also tended to differ in their intrusive thoughts following an unsolved problem; FP participants were more preoccupied about solving the problem than about the quality of their performance, contrary to DP subjects. Results are discussed according to theoretical models of OCD.

Cognitive restructuring in the treatment of psychotic symptoms in schizophrenia: A critical analysis**

This article reviews the 15 empirical studies that have used cognitive restructuring in the treatment of schizophrenia, more specifically for psychotic symptoms (delusions and hallucinations). Three elements are considered before investigating its effectiveness: (a) if subjects are reliably diagnosed with schizophrenia with chronic course and severe impairment; (b) if psychotic symptoms are adequately measured; and (c) if designs are methodologically sound. Our investigation revealed that schizophrenia is not reliably diagnosed and severity is low to moderate. Assessment of psychotic symptoms is satisfactory, but assessment of generalization to other areas is limited. Only five studies possess reliable design and are performed with schizophrenia subjects. These studies suggest that cognitive restructuring is effective to reduce or eliminate hallucinations or delusions in schizophrenia patients.

Meta-analysis of sleep changes in control groups of insomnia treatment trials

A meta‐analysis assessing the magnitude of sleep changes from baseline in placebo‐treated (psychological and pharmacological placebo) and untreated groups issued from independent trials was conducted. Comparisons were then performed to assess if the magnitude of sleep changes in the placebo control groups were significantly different than those of the untreated group. Medline, PsychInfo and Current Contents databases (1990–2004) were searched for primary insomnia treatment studies using a randomized controlled parallel‐group design. Effect sizes were computed for each end‐point variable based on subjective (patient‐reported) and polysomnographic measures. Thirty‐four studies (n = 1392 subjects) met inclusion criteria; twenty‐three used a pharmacological placebo (n = 1163), four used a psychological placebo (n = 81), and seven used a waitlist condition (n = 148). Between‐group comparisons were performed using a random effects model analysis. Significant pre–post changes were observed in the pharmacological placebo condition on several sleep parameters, both on objectively and subjectively measured outcomes [objective and subjective sleep onset latency (SOL) and total sleep time (TST) and subjective wake after sleep onset]. Although a tendency was observed for objective SOL, only the changes on subjective SOL and TST in the pharmacological placebo condition were significantly different from the corresponding changes in the untreated group. No differences were significant for the psychological placebo groups. Although the present findings suggest that sleep may significantly change in response to a pharmacological placebo, conclusions remain tentative because of possible confounds that may arise when comparing groups issued from different trials. Further research directly comparing placebo groups and untreated groups from the same randomized trials remains necessary.

Insomnia in shift work

BACKGROUND Shift work disorder involves insomnia and/or excessive sleepiness associated with the work schedule. The present study examined the impact of insomnia on the perceived physical and psychological health of adults working on night and rotating shift schedules compared to day workers. METHODS A total of 418 adults (51% women, mean age 41.4 years), including 51 night workers, 158 rotating shift workers, and 209 day workers were selected from an epidemiological study. An algorithm was used to classify each participant of the two groups (working night or rotating shifts) according to the presence or absence of insomnia symptoms. Each of these individuals was paired with a day worker according to gender, age, and income. Participants completed several questionnaires measuring sleep, health, and psychological variables. RESULTS Night and rotating shift workers with insomnia presented a sleep profile similar to that of day workers with insomnia. Sleep time was more strongly related to insomnia than to shift work per se. Participants with insomnia in the three groups complained of anxiety, depression, and fatigue, and reported consuming equal amounts of sleep-aid medication. Insomnia also contributed to chronic pain and otorhinolaryngology problems, especially among rotating shift workers. Work productivity and absenteeism were more strongly related to insomnia. CONCLUSION The present study highlights insomnia as an important component of the sleep difficulties experienced by shift workers. Insomnia may exacerbate certain physical and mental health problems of shift workers, and impair their quality of life.

Speed and trajectory of changes of insomnia symptoms during acute treatment with cognitive–behavioral therapy, singly and combined with medication

OBJECTIVES To examine the speed and trajectory of changes in sleep/wake parameters during short-term treatment of insomnia with cognitive-behavioral therapy (CBT) alone versus CBT combined with medication; and to explore the relationship between early treatment response and post-treatment recovery status. METHODS Participants were 160 adults with insomnia (mean age, 50.3 years; 97 women, 63 men) who underwent a six-week course of CBT, singly or combined with 10 mg zolpidem nightly. The main dependent variables were sleep onset latency, wake after sleep onset, total sleep time, sleep efficiency, and sleep quality, derived from sleep diaries completed daily by patients throughout the course of treatment. RESULTS Participants treated with CBT plus medication exhibited faster sleep improvements as evidenced by the first week of treatment compared to those receiving CBT alone. Optimal sleep improvement was reached on average after only one week for the combined treatment compared to two to three weeks for CBT alone. Early treatment response did not reliably predict post-treatment recovery status. CONCLUSIONS Adding medication to CBT produces faster sleep improvement than CBT alone. However, the magnitude of early treatment response is not predictive of final response after the six-week therapy. Additional research is needed to examine mechanisms involved in this early treatment augmentation effect and its impact on long-term outcome.

A Preliminary Evaluation of the Physiological Mechanisms of Action for Sleep Restriction Therapy

Our objective was to investigate the physiological mechanisms involved in the sleep restriction treatment of insomnia. A multiple baseline across subjects design was used. Sleep of five participants suffering from insomnia was assessed throughout the experimentation by sleep diaries and actigraphy. Ten nights of polysomnography were conducted over five occasions. The first two-night assessment served to screen for sleep disorders and to establish a baseline for dependent measures. Three assessments were undertaken across the treatment interval, with the fifth and last one coming at follow-up. Daily cortisol assays were obtained. Sleep restriction therapy was applied in-lab for the first two nights of treatment and was subsequently supervised weekly. Interrupted time series analyses were computed on sleep diary data and showed a significantly decreased wake time, increased sleep efficiency, and decreased total sleep time. Sleepiness at night seems positively related to sleep variables, polysomnography data suggest objective changes mainly for stage 2, and power spectral analysis shows a decrease in beta-1 and -2 powers for the second night of treatment. Cortisol levels seem to be lower during treatment. These preliminary results confirm part of the proposed physiological mechanisms and suggest that sleep restriction contributes to a rapid decrease in hyperarousal insomnia.