Sleep in the laboratory and sleep at home II: comparisons of middle-aged insomnia sufferers and normal sleepers.

STUDY OBJECTIVES: The study compared adaptation responses and sleep pattern differences shown by normal sleepers and insomnia sufferers during lab (LPSG) and home (HPSG) polysomnography. DESIGN: A counter-balanced, matched-group design was used. Participants underwent 3 consecutive nocturnal LPSG's and 3 consecutive nocturnal PSG's in their homes (HPSG's). SETTING: The sleep disorders laboratories at affiliated VA and university medical centers. PARTICIPANTS: Thirty-five (18 women) middle-aged (40 to 59 years) noncomplaining normal sleepers and an age-matched sample of 33 (17 women) individuals who met structured interview criteria for persistent primary insomnia were the study participants. MEASUREMENTS AND RESULTS: A series of multivariate and univariate analyses were conducted with 9 common sleep parameters to address study objectives. Bed partner influences were controlled by conducting separate sets of analyses for those with and without routine home bed partners. The interaction of participant type (normal vs. insomnia), sleep setting, and PSG sequence (HPSG 1st vs. LPSG 1st) affected first night values of sleep efficiency and stage 2 sleep among those without routine bed partners, and REM latency and sleep efficiency among those with routine bed partners. Analyses which controlled for first night and sequencing effects showed a significant participant type x sleep setting interaction among those with bed partners. These latter analyses suggested that LPSG's may underestimate the home sleep time of insomnia sufferers and overestimate the sleep continuity of normal sleepers, at least among those who routinely sleep with a bed partner. CONCLUSIONS: The nocturnal recording site may influence adaptation effects and sleep pattern differences noted between insomnia sufferers and normal sleepers.

Does cognitive-behavioral insomnia therapy alter dysfunctional beliefs about sleep?

STUDY OBJECTIVES: This study was conducted to exam the degree to which cognitive-behavioral insomnia therapy (CBT) reduces dysfunctional beliefs about sleep and to determine if such cognitive changes correlate with sleep improvements. DESIGN: The study used a double-blind, placebo-controlled design in which participants were randomized to CBT, progressive muscle relaxation training or a sham behavioral intervention. Each treatment was provided in 6 weekly, 30-60-minute individual therapy sessions. SETTING: The sleep disorders center of a large university medical center. PARTICIPANTS: Seventy-five individuals (ages 40 to 80 years of age) who met strict criteria for persistent primary sleep-maintenance insomnia were enrolled in this trial. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Participants completed the Dysfunctional Beliefs and Attitudes About Sleep (DBAS) Scale, as well as other assessment procedures before treatment, shortly after treatment, and at a six-month follow-up. Items composing a factor-analytically derived DBAS short form (DBAS-SF) were then used to compare treatment groups across time points. Results showed CBT produced larger changes on the DBAS-SF than did the other treatments, and these changes endured through the follow-up period. Moreover, these cognitive changes were correlated with improvements noted on both objective and subjective measures of insomnia symptoms, particularly within the CBT group. CONCLUSIONS: CBT is effective for reducing dysfunctional beliefs about sleep and such changes are associated with other positive outcomes in insomnia treatment.

Cognitive behavioral therapy for treatment of chronic primary insomnia: a randomized controlled trial.

CONTEXT: Use of nonpharmacological behavioral therapy has been suggested for treatment of chronic primary insomnia, but well-blinded, placebo-controlled trials demonstrating effective behavioral therapy for sleep-maintenance insomnia are lacking. OBJECTIVE: To test the efficacy of a hybrid cognitive behavioral therapy (CBT) compared with both a first-generation behavioral treatment and a placebo therapy for treating primary sleep-maintenance insomnia. DESIGN AND SETTING: Randomized, double-blind, placebo-controlled clinical trial conducted at a single academic medical center, with recruitment from January 1995 to July 1997. PATIENTS: Seventy-five adults (n = 35 women; mean age, 55.3 years) with chronic primary sleep-maintenance insomnia (mean duration of symptoms, 13.6 years). INTERVENTIONS: Patients were randomly assigned to receive CBT (sleep education, stimulus control, and time-in-bed restrictions; n = 25), progressive muscle relaxation training (RT; n = 25), or a quasi-desensitization (placebo) treatment (n = 25). Outpatient treatment lasted 6 weeks, with follow-up conducted at 6 months. MAIN OUTCOME MEASURES: Objective (polysomnography) and subjective (sleep log) measures of total sleep time, middle and terminal wake time after sleep onset (WASO), and sleep efficiency; questionnaire measures of global insomnia symptoms, sleep-related self-efficacy, and mood. RESULTS: Cognitive behavioral therapy produced larger improvements across the majority of outcome measures than did RT or placebo treatment. For example, sleep logs showed that CBT-treated patients achieved an average 54% reduction in their WASO whereas RT-treated and placebo-treated patients, respectively, achieved only 16% and 12% reductions in this measure. Recipients of CBT also showed a greater normalization of sleep and subjective symptoms than did the other groups with an average sleep time of more than 6 hours, middle WASO of 26.6 minutes, and sleep efficiency of 85.1%. In contrast, RT-treated patients continued to report a middle WASO of 43.3 minutes and sleep efficiency of 78.8%. CONCLUSIONS: Our results suggest that CBT represents a viable intervention for primary sleep-maintenance insomnia. This treatment leads to clinically significant sleep improvements within 6 weeks and these improvements appear to endure through 6 months of follow-up.

Psychometric comparisons of the standard and abbreviated DBAS-10 versions of the dysfunctional beliefs and attitudes about sleep questionnaire.

OBJECTIVE: To evaluate the psychometric properties of the DBAS-10, a recently proposed abbreviated version of the Dysfunctional Beliefs and Attitudes About Sleep Scale (DBAS). POPULATION: Two hundred and eleven (69 normal sleepers; 142 insomnia suffers) middle-aged and older adults (age 40-79 years) drawn from two separate cohorts of research volunteers. METHOD: Volunteers in the first cohort (69 normal sleepers; 69 insomnia sufferers) completed the full DBAS on one occasion. Volunteers in the second cohort (73 insomnia sufferers) completed the full DBAS prior to treatment and at multiple subsequent time points to assess treatment-related changes. A series of statistical tests were conducted with one or both cohorts to investigate the comparability of the DBAS-10 and full DBAS, the internal consistency of each instrument, the factor structure of the DBAS-10, and the validity of this instrument. RESULTS: Statistical findings showed that the DBAS-10 correlated highly with the full DBAS, had respectable internal consistency, effectively discriminated normal sleepers from insomnia sufferers, and detected cognitive changes resulting specifically from CBT intervention. Although factor analysis empirically identified three conceptually meaningful DBAS-10 subscales, the subscale structure varied somewhat from previous factor analytic findings with this instrument. CONCLUSIONS: The DBAS-10 generally appears to have very acceptable psychometric properties although subscales previously proposed for this instrument may vary across research populations. Nonetheless, results encourage the use of this instrument in studies concerned with the nature and treatment of sleep-disruptive cognitions.

Slow-wave sleep and waking cognitive performance II: Findings among middle-aged adults with and without insomnia complaints.

Previous studies showing a relationship between nocturnal slow-wave sleep (SWS) and subsequent diurnal performance among young normal sleepers and older insomnia sufferers have provided limited support for the notion that this sleep stage serves a restorative role for neurocognitive functioning. The current study, which examined the relationship between SWS and reaction time performance among middle-aged adults with and without insomnia complaints, was conducted to further explore this possibility. A sample of 31 noncomplaining middle-aged (ages 40 to 59 years) normal sleepers and a like-aged sample of 27 insomnia sufferers, provided data for the current investigation. All participants underwent nocturnal sleep monitoring immediately prior to undergoing a battery of daytime tests that measured simple reaction time, vigilance/signal detection, and complex reaction time. Results showed relationships between reaction time performances on some tasks and some SWS measures among both the normal sleepers and insomnia sufferers. Findings supported our prediction that the presence of sleep pathology (e.g., insomnia) alters the SWS-performance relationship observed, but the results failed to show a consistent relationship between SWS and subsequent performance within either sample. The findings suggest that the specific performance demands of the task in question as well as physiological parameters other than SWS may determine performance as well. Findings for this and previous studies do provide some support for the contention that the neurocognitive restorative value of SWS may change across the lifespan. Possible implications of the study's findings are discussed and directions for future research are considered.

Insomnia and the eye of the beholder: are there clinical markers of objective sleep disturbances among adults with and without insomnia complaints?

Previous findings suggest that some who report insomnia sleep well, whereas some noncomplaining individuals sleep rather poorly. This study was conducted to determine if mood, anxiety, and sleep-related beliefs might relate to perceived sleep disturbance. Thirty-two women and 32 men (aged 40-79 years) with primary insomnia and an aged-matched sample of 61 normal sleepers (31 women, 30 men) completed 6 nocturnal sleep recordings, as well as the Beck Depression Inventory (BDI), the Trait portion of the State-Trait Anxiety Inventory (STAI-2), and the Dysfunctional Beliefs and Attitudes About Sleep Questionnaire. Sleep and interview data were used to subdivide the majority of the sample (n = 108) into objective normal sleepers and subjective insomnia sufferers who seemingly slept well and subjective normal sleepers and objective insomnia sufferers who slept poorly. The 2 subjective subgroups showed the most marked differences on most of the psychometric measures. The findings suggest that the psychological factors scrutinized in this study may mediate sleep satisfaction and/or predict objective sleep difficulties.

Sleep disorders in older people.

Sleep complaints are common among older people. As there are often multiple contributing factors, insomnia should be considered a symptom, and not a diagnosis. There is a high prevalence of sleep apnea and nocturnal myoclonus. When these primary sleep disorders are suspected, the patient should be referred for polysomnography. Use of hypnotics should be discouraged for chronic insomnia. More research is needed to clarify the role of light therapy and melatonin in the treatment of sleep disorders in older people.

Slow-wave sleep and waking cognitive performance among older adults with and without insomnia complaints.

Previous research has shown that healthy young adults with relatively fast reaction times on daytime testing have significantly more nocturnal slow-wave sleep than do age-matched subjects with relatively slow reaction times on such testing. The current study was conducted to examine the relationship between slow-wave sleep and cognitive performance among older adults with and without insomnia complaints. A sample of 32 noncomplaining older (age > or = 60 years) normal sleepers and a like-aged sample of 32 insomniacs, recruited to participate in a larger study, served as subjects. All subjects underwent nocturnal sleep monitoring immediately prior to undergoing a battery of daytime tests that measured simple reaction time, vigilance/signal detection, and complex reaction time. Results from the normal sleepers showed no relationship between daytime cognitive performance measures and a variety of computer-derived nocturnal slow-wave sleep measures. In contrast, insomniac subjects with relatively slow reaction times showed relative deficits in a spectral analytically derived measure of slow-wave power in the 2 to 4 Hz bandwidth. These results suggest that relative performance deficits among some older insomniacs may be related to specific slow-wave sleep deficiencies. However, among older normal sleepers, intersubject differences in performance appear unrelated to slow-wave sleep measures. Additional research is needed to further explore the possible restorative role slow-wave sleep may serve for cognitive functions other than those examined herein.

How many nights are enough? The short-term stability of sleep parameters in elderly insomniacs and normal sleepers.

Temporal stability is an important fundamental quality when measuring sleep parameters, yet it has been infrequently assessed. Generalizability theory was used to estimate the short-term temporal stability of five variables commonly used to characterize insomnia: sleep onset latency, total sleep time, wake after sleep onset, time in bed, and sleep efficiency. Estimates were calculated for 32 elderly primary insomniacs and 32 elderly normal sleepers, both in the lab and at home, using both sleep logs and polysomnography (PSG). A week of recording using either PSG or sleep logs was typically sufficient to achieve adequate stability (defined as G coefficient of at least 0.80) with some notable exceptions: (a) when using log-derived measures with insomniacs, a 3-week average was necessary for wake after sleep onset and (b) more than a 2-week average was necessary for sleep onset latency. Because of the substantial commitment involved in the physiological recording of sleep, alternative forms of aggregation are considered with the intent of improving temporal stability.

The significance and management of persistent primary insomnia: the past, present and future of behavioral insomnia therapies.

Persistent primary insomnia (PPI) is a prevalent and potentially serious condition that compromises the functioning, health status, and quality of lives of millions of individuals around the world. This condition is typically perpetuated by a host of psychological and behavioral mechanisms that often require behavioral interventions. Nonetheless, all too commonly, practitioners underestimate the seriousness of this condition or rely too heavily on symptom focused sedative hypnotic therapy for its treatment. Herein we briefly review the epidemiology of PPI and consider the inadequacies of sedative hypnotics for treating this disorder. Subsequently, we provide rationale for the use of behavioral interventions with this condition and we describe the gradual evolution of the currently available behavioral insomnia treatments and consider promising recent developments such as the emergence of cognitive-behavioral and specially tailored, patient-specific approaches. In closing, we consider the potential usefulness of a combined pharmacological/behavioral intervention for PPI and present a number of important research questions to address in future studies of the behavioral insomnia therapies.

Factors that disturb sleep in nursing home residents.

The purpose of this cross-sectional survey was to examine subjective sleep quality, and identify factors that disturb sleep in cognitively intact nursing home (NH) residents. We interviewed 51 cognitively intact NH residents using a validated instrument, the Pittsburgh Sleep Quality Index (PSQI). Questions regarding the environment, symptoms suggestive of restless leg syndrome, and periodic leg movements were also asked. Three individuals were unable to answer all the questions and, therefore, analyses were performed on 48 subjects. Seventy-three percent of the subjects were identified as "poor" sleepers based upon a total PSQI score > 5. Factors that disturbed the residents' sleep three or more times a week were: nocturia (71%), environment-related noise or light (38%), pain (33%), feeling too hot (6%) and leg cramps (6%). On multiple regression analysis, poor sleep correlated with depressive symptoms and comorbidity, not with age or gender. Poor sleep quality is common among cognitively intact NH residents. In our study, nocturia, environmental factors and pain were the most commonly perceived causes of sleep disturbance. Poor sleep independently correlated with depressive symptoms and comorbidity. These findings should be kept in mind when evaluating sleep complaints in the nursing home.

Sleep in the laboratory and sleep at home: comparisons of older insomniacs and normal sleepers.

Many laboratory polysomnographic (LPSG) studies have shown only modest sleep differences between insomniacs and matched, noncomplaining normal controls. However, the extent to which LPSG methodology affects the outcome of such comparisons has yet to be tested. In the current investigation, 32 (16 females, 16 males) older (age > or = 60 years) insomniacs and an age-matched and gender-matched sample of 32 noncomplaining normal sleepers underwent three consecutive nights of LPSG monitoring and another three consecutive nights of PSG monitoring in their homes (HPSG). By random assignment, one-half of the subjects in each group underwent LPSG first, whereas the remaining subjects underwent HPSG first. Each PSG recording was blindly scored using conventional scoring criteria, and resulting measures of total sleep period, total sleep time, sleep efficiency percent, stage 1 time, slow-wave sleep time, and rapid eye movement latency were used to compare the two subject groups within each PSG recording site (i.e. lab and home). Statistical analyses showed the normals sleepers and insomniacs evidenced similar pronounced first night effects (FNEs) when undergoing LPSG. However, neither mean values of the selected sleep parameters nor measures reflecting their night-to-night variability differentiated the insomniacs from the normal sleepers when such measures were derived from LPSG. In contrast, FNEs were generally absent for both subject groups when they underwent HPSG. Moreover, the insomniacs displayed significantly greater variability in several of their sleep measures during HPSG than did the normal sleepers. Overall, results suggest FNEs are a concern mainly when using LPSG, and HPSG may be more sensitive than LPSG for documenting sleep differences between normal sleepers and insomniacs. Additional studies are needed to determine if the findings reported herein are similar for young and middle-aged adults.

Do our methods lead to insomniacs' madness?: Daytime testing after laboratory and home-based polysomnographic studies.

Complaints of daytime dysfunction are common among chronic insomniacs, but laboratory comparisons of insomniacs and age-matched and gender-matched normal controls have generally failed to document these complaints. However, a few studies, which allowed subjects to sleep in their homes on the nights before daytime testing, have shown some relative diurnal deficits among insomniacs. The current study compared the effects of nocturnal laboratory and home polysomnogram (PSG) studies on subsequent daytime test results among older insomniacs and normal sleepers. Insomniacs (n = 32) and normal sleepers (n = 32) were randomly assigned to first undergo three nights of nocturnal PSG monitoring either in the sleep laboratory (16 insomniacs, 16 normal sleepers) or in their homes (16 insomniacs, 16 normal sleepers). Following the third night of PSG monitoring, subjects spent 1 day in the sleep laboratory, where they completed a four-trial multiple sleep latency test along with four trials of a computer-administered performance test battery. Results showed that insomniacs, as a group, were slightly, albeit consistently, sleepier than were normal sleepers following nights of home sleep monitoring, but a reverse of this trend was found among subjects who underwent nocturnal laboratory PSG before daytime testing. Furthermore, normal sleepers showed faster reaction times on a signal detection task than did insomniacs within the subgroup who underwent home PSGs prior to such testing. However, within the subgroup that underwent nocturnal laboratory PSGs, insomniacs' signal detection reaction times were significantly faster than those shown by normal sleepers. Results provide some support for the speculation that the nocturnal PSG monitoring site, used as a precursor to daytime testing, may systematically affect daytime comparisons between insomniacs and matched controls. Moreover, these results suggest that the use of home-based nocturnal PSG monitoring prior to daytime testing may provide an enhanced understanding of insomniacs' diurnal complaints.

Reversible parkinsonism and cognitive impairment with chronic valproate use.

Following our initial report of the insidious development of reversible, valproate-induced hearing, motor, and cognitive dysfunction in two patients, we evaluated 36 patients in an epilepsy clinic who had been taking therapeutic levels of valproate for at least 12 months; 29 of these patients were examined according to a prospective protocol. We observed varying degrees of parkinsonism and cognitive impairment, from none to severe. Discontinuation of valproate in 32 affected patients led to subjective and objective improvement on follow-up testing at least 3 months later. Improvement was greatest in patients who were affected most. We conclude that a syndrome of reversible parkinsonism and cognitive impairment may develop insidiously in patients who have been treated with valproate for more than 12 months. The association with valproate may be overlooked due to the insidious onset.

The empirical identification of insomnia subtypes: a cluster analytic approach.

Over the past 15 years, there has been considerable debate concerning the extent to which insomnia patients can be classified into diagnostic subtypes. Despite this debate, relatively little research has been conducted to empirically determine whether naturally occurring insomnia subtypes might be identified within populations of sleep clinic patients. In the current study we used a hierarchical cluster analysis to empirically identify subtypes among a mixed group of normal sleepers and the insomnia outpatients who presented to our sleep center over the past decade. Using factor-analytically derived composite variables that summarized data obtained from sleep history questionnaires and polysomnographic monitoring, this clustering procedure resulted in the identification of 14 subgroups that varied between four and 34 patients/subjects in size. Subsequently, subgroup mean scores for the composite variables used in the clustering procedure were used to construct profiles for each of the 14 clusters. A multivariate profile analysis, employed to elucidate subgroup differences, showed that these cluster profiles differed in terms of their configural shapes, average elevations, and degrees of interscale differences. Furthermore, both DSM-III-R (American Psychiatric Association) and International Classification of Sleep Disorders (ICSD) insomnia diagnoses, assigned independent of cluster findings, suggested that these subtypes differed significantly in regard to their diagnostic compositions. Nevertheless, a far-from-perfect concordance was observed between such clinically assigned diagnoses and cluster group membership. In fact, many of the empirically identified groups were composed of various DSM-III-R and/or ICSD diagnostic subtypes. These results provided only partial support for current DSM and ICSD insomnia categories. However, our results support the existence of multiple, clinically discrete insomnia subtypes and provide information that may be useful in future revisions of current insomnia nosologies.

Comparison of cognitive-behavioral therapy and clonazepam for treating periodic limb movement disorder.

Many patients with periodic limb movement disorder (PLMD) display inadequate sleep hygiene, and others decline conventional pharmacologic intervention for their form of sleep disturbance. Nonetheless, the use of nonpharmacologic therapies with PLMD remains unexplored. The current study was designed to compare the short-term treatment effects of a cognitive-behavioral therapy (CBT) and conventional pharmacotherapy (clonazepam) among a group of insomniacs with PLMD. The 16 subjects participating in this study first underwent baseline assessment procedures, including completion of a sleep log for 2 weeks, an ambulatory polysomnogram (APSG) and an Insomnia Symptom Questionnaire (ISQ). They then were randomized either to CBT (n = 8) or standard clonazepam therapy (n = 8). Subjects maintained sleep logs throughout a 4-week treatment and then completed a second APSG and ISQ. Comparison of pre- and post-treatment data suggested that the two treatments led to equal improvements in sleep log measures of sleep-wake times and ISQ measures of subjective sleep concerns. Patients treated with CBT showed a decrease in daytime napping, whereas the clonazepam group reported increased napping. Conversely, those treated with clonazepam showed larger declines in periodic limb movement-arousals per hour of sleep than did the CBT group. Post-treatment interviews suggested that both CBT and clonazepam therapies were generally well tolerated by study participants. It is concluded that both treatments may be useful for PLMD but that the two treatments may have contrasting effects across selected measures of improvement. Additional research is needed to examine the long-term efficacy of CBT as a primary or adjunctive treatment for varying levels of PLMD severity.

Subjective estimates of sleep differ from polysomnographic measurements in obstructive sleep apnea patients.

It is well established that, as a group, insomnia patients overestimate sleep onset latency (SOL) and underestimate total sleep time (TST) when compared to objective polysomnographic (PSG) findings. Whether a similar phenomenon occurs with other sleep disorders is not fully established. We compared the PSG sleep of 84 patients with suspected sleep apnea (SA) to their subjective experience of sleep reported on a sleep diary the morning after PSG testing. Both patients with SA (SA+) and those without (SA-) tended to overestimate SOL, but the SA+ group (n = 50) made larger overestimations (p < 0.02). The SA+ and SA- groups also differed in their accuracy at estimating TST, with SA+ patients underestimating TST (p < 0.05). These findings support the premise that marked discrepancies between subjective and PSG-determined sleep may not be limited to insomnia, but present in other sleep disorders as well, and should be appreciated by practitioners when obtaining sleep histories.

The distribution and clinical significance of sleep time misperceptions among insomniacs.

It is well recognized that sleep time misperceptions are common among insomniacs, but little is known about the distribution and clinical significance of these subjective distortions. The current investigation was conducted to examine the distribution of sleep time misperceptions among a large (n = 173), diverse group of insomniacs and to determine if such misperceptions might relate to the patients' clinical characteristics. Consistent with previous studies, our subjects, as a group, produced sleep estimates that were significantly (p < 0.0001) lower than polysomnographically determined sleep times. However, patients' sleep time perceptions were widely distributed across a broad continuum, which ranged between gross underestimates and remarkable overestimates of actual sleep times. Results also showed that subgroups, formed on the basis of presenting complaints and diagnostic criteria (i.e. International Classification of Sleep Disorders nosology), differed in regard to the magnitude and direction of their sleep distortions. Moreover, these differences appeared consistent with the types of objective sleep disturbances these subgroups commonly experience. Hence, the tendency to underestimate actual sleep time is not a generic attribute of all insomniacs. Furthermore, it appears that the accuracy and nature of sleep time perceptions may relate to the type of sleep pathology underlying insomniacs' presenting complaints.