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.

Subjective total insomnia: an example of sleep state misperception.

Sleep state misperception (SSM) is the diagnostic term proposed in the International Classification of Sleep Disorders to describe those insomniacs who mislabel their sleep as wakefulness. Although sleep misperception has long been recognized among insomnia patients, it is debatable whether this clinical finding warrants a distinctive diagnosis or simply represents an extreme variation of other, more common forms of insomnia. We present two cases to explore the clinical meaningfulness of SSM. It is concluded that SSM represents a distinctive, albeit rare, sleep disorder. However, refinements in existing diagnostic criteria may be needed to improve the meaningfulness of the SSM diagnosis.

Use of in vivo desensitization to treat a patient's claustrophobic response to nasal CPAP.

Continuous positive airway pressure (CPAP) has proven to be a safe, effective treatment for sleep apnea patients. However, many patients display claustrophobic reactions to the CPAP nasal mask and cannot tolerate this treatment. The current report describes the successful application of in vivo desensitization with a male apnea patient who initially failed CPAP therapy due to his claustrophobia. Over the course of treatment, the patient became able to tolerate using his CPAP device throughout his nocturnal sleep periods. Moreover, follow-up visits scheduled 6 months and again at 6 1/2 years after behavioral treatment showed that the patient continued to use CPAP on a regular basis. It is concluded that in vivo desensitization therapy may be useful in assisting claustrophobic patients to tolerate nasal CPAP. Results are discussed in view of the specific features of the case presented, and future applications of this behavioral procedure are encouraged.

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.

Daytime functioning and nighttime sleep before, during, and after a 146-hour tennis match.

Two adult males (ages 31 and 35 years) were studied while they participated in a week-long marathon tennis match under conditions of extreme sleep restriction (4-5 h reductions per night). Polysomnographic monitoring was conducted on the two nights prior to the marathon, continuously throughout the match, and on two recovery nights. In addition, measures of daytime sleepiness, mood state, and cognitive performance were obtained during the course of the study. Despite undergoing marked sleep restriction, both players continued to obtain their usual (baseline) amounts of slow wave sleep throughout the marathon. Both players showed a gradually increasing tendency toward daytime dozing across the first few days of the marathon. This tendency decreased on the fifth day but increased again on the sixth day of the match. Also, both players showed a pre- to postmatch decline on some cognitive measures. However, the players differed markedly in their ratings of sleepiness, mood ratings, recovery sleep patterns, and endurance with respect to the demands of the match. Results appear to be consistent with previous laboratory studies in documenting the primacy of the "slow wave sleep drive." Given the marked differences observed between the players, research designed to identify factors that predict response to sleep loss seems to be warranted.

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.

Sleep variability across consecutive nights of home monitoring in older mixed DIMS patients.

Twenty patients with difficulties initiating and maintaining sleep (DIMS) were monitored in their homes for three consecutive nights using ambulatory polysomnography (PSG). Following each night of monitoring, patients provided subjective ratings of sleep disturbance and tolerance of the PSG equipment. Friedman analyses of variance performed on the objective and subjective parameters showed that the sample, as a whole, evidenced no systematic first night effects (FNE) in response to monitoring. Inspection of the data from each individual subject, nevertheless, showed that half of the sample did experience multiple FNE. Further, several scales from the Minnesota Multiphasic Personality Inventory discriminated those patients who showed multiple FNE from those who did not. However, far more striking was the finding that clinically and statistically significant intrasubject variability across nights was observed for each sleep parameter measured. Given this finding, a single ambulatory PSG study may not fully convey the nature of the sleep disturbance experienced by the DIMS patient even when FNE are absent. We thus, recommend multiple ambulatory sleep studies for those clinical and research situations in which it is necessary to document patients' night-to-night sleep variability. In contrast, when the goal of the PSG study is that of determining a sleep diagnosis, a single ambulatory study, in combination with other clinical data, may be sufficient.

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.

Aerobic fitness, acute exercise and sleep in older men.

In the current study 12 aerobically fit and 12 sedentary older men underwent two nocturnal polysomnographic (PSG) studies. A control PSG was conducted following a day without aerobic activity, whereas a postexercise PSG study was conducted following an afternoon session of exhaustive aerobic exercise. In addition to deriving usual sleep parameters, a computer scoring program was used to count the number of individual electroencephalographic (EEG) slow waves in each PSG tracing. Multivariate and univariate analyses showed that the fit subjects had shorter sleep onset latencies, less wake time after onset, fewer discrete sleep episodes, fewer sleep stage shifts during the initial portion of the night, less stage 1 sleep, a higher sleep efficiency and more total slow waves during both PSGs than did the sedentary subjects. Although no main effects were found for the acute exercise challenge, post hoc analyses showed that high levels of body heating during exercise predicted increased sleep fragmentation for both fit and sedentary subjects. These findings provide initial support for the contention that exercise and fitness may have significant effects on the sleep of older men. However, results also suggest that high levels of body heating resulting from a single exercise challenge may have adverse effects. Implications of the study are discussed and suggestions for future research are provided.

Periodic limb movement variability in older DIMS patients across consecutive nights of home monitoring.

Older difficulty initiating and/or maintaining sleep (DIMS) patients who met criteria for periodic limb movement disorder (PLMD) were monitored for three consecutive nights in their homes using ambulatory polysomnography (PSG). Correlational analyses of the group data suggested little night-to-night variability in either movement indices or movement-related arousal indices for this sample. However, within-subjects comparisons suggested considerable variability in these indices and other sleep measures across nights. Nevertheless, for most subjects, the variability noted for these indices appeared to have little effect on PLMD severity classification or clinical treatment decisions derived from blind examinations of PSGs. Further, the initial PSG study generally led to a representative severity classification and clinical decision. Additional research is needed to determine the generalizability of these results to younger subjects, patients with complaints of excessive somnolence and other methods of home PSG monitoring.

Polysomnographic assessment of DIMS: empirical evaluation of its diagnostic value.

This investigation examined the diagnostic value of polysomnography (PSG) for evaluating disorders of initiating and maintaining sleep (DIMS). The sample consisted of 100 outpatients who presented to the Duke Sleep Disorders Center with a complaint of chronic insomnia. All patients were given comprehensive medical, psychiatric, behavioral, and ambulatory PSG evaluations. Sleep disorder diagnoses were assigned using the criteria of the Association of Sleep Disorders Centers. Overall, PSG yielded important diagnostic information in 65% of the sample: 34% were given a primary sleep disorder diagnosis that was heavily dependent on PSG data [periodic movements of sleep (PMS) = 25%, apnea = 3%, and subjective insomnia = 6%]; 15% were given a secondary diagnosis of one of these three disorders; and PSG ruled out suspected PMS in 9% and sleep apnea in 7% of the sample. Patients greater than 40 years of age had a significantly higher rate of positive PSG findings than younger patients. Using only the clinical exam, two experienced sleep clinicians were able to predict only 14 of 25 PMS cases and one of three cases of sleep apnea. Based on these data, we suggest using PSG routinely with older insomniacs and with younger patients who fail initial treatment.

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.

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.

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.

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.

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.

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.

Ambulatory polysomnography: technical aspects and normative values.

Ambulatory polysomnographic (APSG) assessment of sleep disorders is now possible, but the technique of APSG is sufficiently different from in-laboratory PSG that normative data from in-laboratory PSG may not apply to APSG. This paper reviews the technical aspects of APSG and presents normative APSG data from 20 older healthy males. Subjects underwent medical and psychiatric screening before completing APSG in their homes. Total sleep time and the rapid-eye-movement sleep latency (RL) were both shorter than those reported by others using traditional in-laboratory techniques. The shorter total sleep may be related to behaviors at home that impinge upon sleep. The shorter RL may be related to differences in calculation methods. Periodic limb movements were common in our subjects but did not contribute to sleep disturbance. We conclude that APSG is sufficiently different from traditional PSG as to warrant collection of a large normative data base.