EEG sleep studies in patients with generalized anxiety disorder

Sleep polygraphic recordings were performed during 3 consecutive nights in 12 inpatients with generalized anxiety disorder (GAD) in comparison with age- and sex-matched groups of patients with major depressive disorder (MDD) and normal subjects. GAD patients differed significantly from those with MDD. A lower number of awakenings and stage shifts in night 1 and the mean of the 3 nights and a shorter rapid eye movement (REM) duration in night 1 but longer REM latency in the mean of the 3 nights were observed in GAD in comparison to MDD. GAD patients also showed a significantly longer sleep onset latency and shorter duration of total sleep time and Stage 2 than control subjects. Electroencephalographic sleep recordings, as well as other laboratory tests, may help the clinician to differentiate anxiety from depressive disorders.     

Electroencephalographic sleep measures in prepubertal depression.

Two nights of electroencephalographic (EEG) sleep recording were performed in a group of prepubertal subjects with major depressive disorder (MDD) (n = 36, mean age = 10.4, SD = 1.5) and age-matched normal control children (n = 18, mean age = 10.1, SD = 1.6). All subjects were medically healthy and free of medications at the time of the study. There were no significant group differences for any major sleep variable after the initial adaptation night in this study. One subgroup of MDD subjects (n = 8) showed reduced REM latency on both recording nights, decreased stage 4 sleep, and increased REM time; this subgroup had significantly higher severity scores for depression but did not otherwise appear to be clinically distinct from the rest of the MDD subjects. Overall, the results indicate that the EEG sleep changes associated with depression in adults occurred less frequently in prepubertal MDD subjects.     

Partial sleep deprivation therapy combined with sertraline affects subjective sleep quality in major depressive disorder

BACKGROUND AND PURPOSE: Earlier studies have shown an association between mood disorders and sleep regulation. Total or partial sleep deprivation was demonstrated to have rapid antidepressive effects in depression. Depressive symptoms recur after one night of recovery sleep, but relapse is less when patients are receiving medication. In this study, we examined the subjective sleep quality changes with the antidepressive therapy using partial sleep deprivation plus sertraline and sertraline monotherapy in patients with major depressive disorder. PATIENTS AND METHODS: Thirteen patients received six partial sleep deprivation therapies in addition to sertraline; the sleep schedule on deprivation nights started at 11:00 p.m. and ended at 3:00 a.m. Eleven patients were treated with sertraline monotherapy as a control group. Six nights of partial sleep deprivation were completed in the first two weeks. Subjective sleep quality was evaluated with the Pittsburgh Sleep Quality Index (PSQI); depression and the accompanying anxiety were also assessed at baseline and at the end of the fourth week. RESULTS: The late partial sleep deprivation (LPSD) group showed less increase in estimated sleep duration and less significant improvement in subjective sleep quality than the control group. Although decreased sleep latency and increased sleep efficiency are associated with the sleep deprivation, contrary results were found in our study. CONCLUSIONS: In conclusion, changes in subjective sleep quality could occur relative to the combined partial sleep deprivation therapy and to pharmacotherapy and must be differentiated from the rapid effects of sleep deprivation therapy and objective polysomnographic measures.     

Peri-sleep-onset cortisol levels in children and adolescents with affective disorders.

BACKGROUND: Changes in the hypothalamic-pituitary-adrenal (HPA) axis, as evidenced by patterns of cortisol secretion, have been of interest in understanding depression and anxiety disorders across the life span. Previous studies of pediatric depression have pointed to the period around sleep onset as a key time point for observing alterations in cortisol secretion associated with affective disorders. Evidence also indicates that pubertal development may influence the expression of HPA dysregulation. We hypothesized that adolescents with depression and youth with anxiety disorders exhibit elevated peri-sleep-onset cortisol. METHODS: Plasma cortisol was sampled every 20 min around sleep onset from children and adolescents with major depressive disorder (n = 116), anxiety disorders (n = 32), or no history of psychiatric disorder (control; n = 76). Sleep onset was determined by polysomnography. Classification of participants as children or adolescents was based on Tanner staging of pubertal maturation. RESULTS: Children with anxiety disorders had higher peri-sleep-onset cortisol than children with depression or control children. Adolescents with depression had marginally higher peri-sleep-onset cortisol than control adolescents and significantly higher peri-sleep-onset cortisol than children with depression. CONCLUSIONS: Depression and anxiety are associated with altered cortisol secretion around sleep onset, and these changes appear to be influenced by pubertal maturation.     

Effect of preexisting borderline personality disorder on clinical and EEG sleep correlates of depression

Two groups of depressed patients were studied: (1) The first group comprised 15 inpatients who were diagnosed as predominantly “borderline personality disorders” based on DSM-III and psychometric test criteria; these patients were also clinically depressed. (2) The second group consisted of 18 inpatients who met Research Diagnostic Criteria (RDC) for major depressive disorder (MDD) but who failed to meet the above criteria for borderline personality disorder. Subsequent to the selection of patients for study, an independent diagnostic evaluation revealed that MDD patients with borderline personality disorder had higher ratings than nonborderline MDD patients on items from the Schedule for Affective Disorders and Schizophrenia such as total anxiety, anger, schizotypal features, miscellaneous psychopathology, and alcohol and drug abuse. A further breakdown of miscellaneous psychopathology items revealed greater subjective anger, self-pity, and demandingness in borderline patients. A comparison of RDC subtypes in the two groups revealed a significant increase in bipolar II diagnoses in the borderline MDD group. Electroencephalographic (EEG) sleep studies carried out in a subsample of MDD borderline (n=8) and primary MDD nonborderline (n=11) patients revealed no significant differences between the two groups. Thus, in contrast to the EEG sleep findings reported for secondary depression with other antecedent psychiatric disorders, the present study indicated that a preexisting diagnosis of borderline personality disorder in MDD patients did not alter the characteristics short latency of rapid eye movement (REM) sleep and the sleep continuity disturbances reported in primary MDD. These data confirm earlier reports by Akiskal (1981), Carroll et al. (1981), and McNamara et al. (1982) concerning the phenomenological and EEG sleep profiles of borderline patients.     

Sleep-related functioning in euthymic patients with bipolar disorder, patients with insomnia, and subjects without sleep problems

OBJECTIVE: The authors investigated sleep-related functioning in euthymic patients with bipolar disorder. METHOD: Euthymic patients with bipolar disorder (N=20), patients with insomnia (N=20), and subjects with good sleep (N=20) were compared on data from interviews and questionnaires and on findings from eight consecutive days and nights of sleep diary keeping (subjective sleep estimate) and actigraphy (objective sleep estimate). RESULTS: Seventy percent of the euthymic patients with bipolar disorder exhibited a clinically significant sleep disturbance. Compared with the other groups, the bipolar disorder group exhibited impaired sleep efficiency, higher levels of anxiety and fear about poor sleep, lower daytime activity levels, and a tendency to misperceive sleep. The bipolar disorder group held a level of dysfunctional beliefs about sleep that was comparable to that in the insomnia group and significantly higher than that in the good sleeper group. CONCLUSIONS: Insomnia is a significant problem among euthymic patients with bipolar disorder. Components of cognitive behavior therapy for insomnia, especially stimulus control and cognitive therapy, may be a helpful adjunct to treatment for patients with bipolar disorder.     

A family study of major depressive disorder in a community sample of adolescents

BACKGROUND: Family studies provide a useful approach to exploring the continuities and discontinuities between major depressive disorder (MDD) in children and adolescents and MDD in adults. We report a family study of MDD in a large community sample of adolescents. METHODS: Probands included 268 adolescents with a history of MDD, 110 adolescents with a history of nonmood disorders but no history of MDD through age 18 years, and 291 adolescents with no history of psychopathology through age 18 years. Psychopathology in their 2202 first-degree relatives was assessed with semistructured direct and family history interviews, and best-estimate diagnoses were derived with the use of all available data. RESULTS: The relatives of adolescents with MDD exhibited significantly elevated rates of MDD (hazard ratio [HR], 1.77; 95% confidence interval [CI], 1.46-2.31), dysthymia (HR, 1.79; 95% CI, 1. 11-2.87), and alcohol abuse or dependence (HR, 1.29; 95% CI, 1.05-1. 53), but not anxiety disorders, drug abuse or dependence, or antisocial and borderline personality disorder. In contrast, anxiety, substance use, and disruptive behavior disorders in adolescents were not associated with elevated rates of MDD in relatives. However, the relatives of probands with anxiety and substance use disorders exhibited elevated rates of anxiety and substance use disorders, respectively. CONCLUSIONS: The results provide evidence of the familial aggregation of adolescent MDD, and also indicate that there is a considerable specificity in the pattern of familial transmission. In addition, we found preliminary evidence of the familial aggregation of adolescent anxiety and substance use disorders.     

Relationship between objective and subjective sleep measures in depressed patients and healthy controls

The purpose of this study was to correlate subjective sleep characteristics based on questionnaire response, and objective sleep EEG features based on polysomnography, in 52 patients with major depressive disorders (MDD) and 49 healthy controls. With the exception of the number of awakenings, subjective and objective sleep measures were strongly correlated in both groups. Patients and controls were able to accurately judge time in bed, total sleep time and sleep latency. However, sleep quality, depth, and how rested participants felt upon awakening were not strongly correlated with objective sleep characteristics, particularly in those with MDD The findings suggest that estimates such as total sleep time and sleep latency, obtained from questionnaire data, bear a strong resemblance to objective polysomnographic characteristics in both those with MDD and healthy controls. Patients with MDD do not show sleep-state misperceptions although depressed women are more accurate in estimating sleep characteristics than depressed men. Depression and Anxiety 5:97–102, 1997. © 1997 Wiley-Liss, Inc.     

Age-related sleep change: Gender and estrogen effects on the subjective-objective sleep quality relationships of healthy, noncomplaining older men and women

OBJECTIVE: The sleep of a large group of healthy older men and women was studied in an effort to better understand the relationship between self-reported subjective and objectively measured sleep quality. METHODS: We examined the baseline subjective and objective sleep quality of 150 healthy older (67.5+/-0.5) men (n=55) and women (n=95). Subjects were carefully screened to exclude sleep disorders and did not complain of significant sleep disturbance. RESULTS: Despite their noncomplaining status, significant proportions of both women (33%) and men (16%) endorsed Pittsburgh Sleep Quality Index (PSQI) scores of >5, a criterion indicative of significant sleep disturbance. When examined as a function of this criterion, objective sleep was significantly impaired with longer sleep latency, less total sleep time, and lower sleep efficiency, for the high-PSQI (H-PSQI) men compared to low-PSQI (L-PSQI) men. These L-PSQI versus H-PSQI differences were much weaker for women and disappeared completely in women on estrogen replacement therapy. CONCLUSIONS: This large group of healthy, noncomplaining older adults manifested significantly disturbed sleep relative to healthy younger subjects, indicating that while aging results in significant changes in sleep, it does not of necessity result in complaints of insomnia and that many healthy older individuals apparently adapt their perception of what is "acceptable" sleep. A considerable correspondence between subjective and objective sleep quality was observed for men but not for women, despite women more frequently endorsing the presence of significant sleep disturbance. This finding is provocative and suggests that what we consider objective measures of good-quality sleep may be appropriate for older men but that older women may be evaluating their sleep quality using other criteria.     

Sleep is undisturbed in elderly, depressed individuals who have not sought health care

Sleep deficits are commonly found in geriatric depressed patients, particularly shortened rapid eye movements (REM) latency, disturbed sleep continuity, and decreased slow wave sleep (SWS). Here we report the sleep patterns of community volunteers responding to ads about memory loss and depression. The two groups, 24 geriatric-onset major depressive disorder (MDD) subjects with a minimal history of seeking treatment for depression and 24 gender- and age-matched control subjects, significantly differed from each other on only one measure of sleep--sleep latency; the MDD group showed a modest but significant shortening of latency to fall asleep. All other sleep/wake measures, including REM latency, temporal distribution of REM sleep across the night, SWS, and measures of nighttime wakefulness did not differ between groups. This lack of significant sleep disturbance suggests that the sleep deficits reported in many studies of major depression may be related to factors underlying treatment-seeking behaviors, physical health status, severity of the depression, or heterogeneity within the MDD population with some types seeking treatment and others not seeking it, rather than depressive state per se. The data indicate that community-dwelling healthy elderly individuals who have a diagnosed major depression but who have not actively sought health care do not necessarily manifest the sleep disturbances thought to be characteristic of major depressive illness.     

Effect of comorbid anxiety disorders on the hypothalamic-pituitary-adrenal axis response to a social stressor in major depression.

BACKGROUND: Major depressive disorder (MDD) is often complicated by anxiety symptoms, and anxiety disorders occur in approximately 30% of mood cases. This study examined the influence of anxiety comorbidity on the hypothalamic-pituitary-adrenal (HPA) axis response to stress in patients with MDD. METHODS: Untreated subjects with pure MDD (n = 15), MDD with comorbid anxiety disorders (n = 18), and pure anxiety disorders (n = 15) were recruited by advertising. Age- and gender-matched control subjects were recruited for each subject with a psychiatric diagnosis (n = 48). All subjects underwent a social stressor, the Trier Social Stress Test (TSST), and blood was collected for adrenocorticotropic hormone (ACTH) and cortisol assay. RESULTS: When all depressed patients (n = 33) were compared with their matched control subjects (n = 33), they showed a significantly greater ACTH response to the stressor; however, this exaggerated ACTH response was exclusively due to the depressed group with comorbid anxiety disorders. A similar but nonsignificant effect was observed in the cortisol response. Subjects with pure mood or pure anxiety disorders showed normal ACTH and cortisol responses to the TSST. All patient groups showed similar levels of TSST-induced anxiety. CONCLUSIONS: Comorbid anxiety disorders might play a role in the increased activation of the HPA axis observed in patients with major depression.     

Face-emotion processing in offspring at risk for panic disorder

OBJECTIVE: Panic disorder (PD) has been linked to perturbed processing of threats. This study tested the hypotheses that offspring of parents with PD and offspring with anxiety disorders display relatively greater sensitivity and attention allocation to fear provocation. METHOD: Offspring of adults with PD, major depressive disorder (MDD), or no disorder (ages 9-19) viewed computer-presented face photographs depicting angry, fearful, and happy faces. Offspring rated (1) subjectively experienced fear level, (2) how hostile the face appeared, and (3) nose width. Attention allocation was indexed by latency to perform ratings. RESULTS: Compared with offspring of parents without PD (n = 79), offspring of PD parents (n = 65) reported significantly more fear and had slower reaction times to rate fear, controlling for ongoing anxiety disorder in the offspring. Offspring with an anxiety disorder (n = 65) reported significantly more fear than offspring without an anxiety disorder but not when parental PD was controlled. Social phobia but no other anxiety disorder in offspring was associated with slower reaction times for fear ratings (but not greater fear ratings). Parental PD and offspring social phobia independently predicted slower reaction time. CONCLUSIONS: Results support an association between parental PD and offspring responses to fear provocation. Social phobia in children may have a specific relationship to allocation of attention to subjective anxiety during face viewing.     

Clinical characteristics of depressive symptoms in children and adolescents with major depressive disorder

OBJECTIVE: Very few studies have compared the symptoms of major depressive disorder (MDD) and rates of comorbid psychiatric disorders between depressed children and adolescents. The aim of this study was to reproduce and extend these findings. METHOD: The Kiddie Schedule for Affective Disorders and Schizophrenia, present version (KSADS-P) was administered to parents (about their children) and in face-to-face interviews with 916 subjects aged 5.6 to 17.9 years with MDD (DSM criteria) (715 adolescents and 201 children; 348 male and 568 female). The subjects were consecutive referrals to an outpatient mood and anxiety disorders clinic. RESULTS: Depressed adolescents had significantly more hopelessness/helplessness, lack of energy/tiredness, hypersomnia, weight loss, and suicidality compared with children (p values < or = .001). In comparison with children, adolescents had significantly more substance abuse and less comorbid separation anxiety disorder and attention-deficit/hyperactivity disorder (p values < or = .001). Depressed female adolescents had significantly more suicidality than depressed male adolescents (p < or = .001). There were no other sex differences between males and females. The symptoms of depressed adolescents grouped into 3 factors (endogenous, negative cognitions/suicidality, and appetite/weight), whereas the symptoms in children grouped into 2 factors (endogenous/negative cognitions/suicidality and appetite/weight). CONCLUSIONS: These results provide further evidence for the continuity of MDD from childhood to adolescence.     

Comparative effects of mirtazapine and fluoxetine on sleep physiology measures in patients with major depression and insomnia

BACKGROUND: Sleep complaints are common in patients with major depressive disorder (MDD). Both MDD and antidepressant drugs characteristically alter objective sleep measures. This study compares the effects of mirtazapine and fluoxetine on sleep continuity measures in DSM-IV MDD patients with insomnia. METHOD: Patients (N = 19) received initial baseline polysomnography evaluations over 2 consecutive nights. Subjects were randomly assigned to either fluoxetine (20-40 mg/day) or mirtazapine (15-45 mg/day) treatment for an 8-week, double-blind, double-dummy treatment trial. Single-night polysomnograms were conducted at weeks 1, 2, and 8, with depression ratings assessed at baseline and weeks 1, 2, 3, 4, 6, and 8. Statistical analysis was performed by repeated-measures analysis of variance followed by Dunnet's post hoc analyses. RESULTS: Patients receiving mirtazapine (N = 8) had significant improvement in objective sleep physiology measures at 8 weeks. Improvements in sleep latency, sleep efficiency, and wake after sleep onset were significant after only 2 weeks of mirtazapine treatment. No significant changes in sleep continuity measures were observed in the fluoxetine group (N = 11). Both groups improved clinically in mood and subjective sleep measures from baseline, with no differences between groups. CONCLUSION: These data demonstrate the differential effects of mirtazapine and fluoxetine, with significant improvement in favor of mirtazapine, on objective sleep parameters in MDD patients with insomnia.     

Cholinergic REM induction response: separation of anxiety and depression

Five groups of subjects underwent EEG sleep recordings, arecoline rapid eye movement (REM) induction response testing, and Schedule for Affective Disorders and Schizophrenia (SADS) interview. Group I: 20 patients with primary major depressive disorder (MDD) (endogenous) without any coexisting anxiety disorder; Group II: 19 primary MDD (endogenous) patients with secondary panic, GAD, or phobic disorders; Group III: 18 patients with primary anxiety disorder without coexisting MDD; Group IV: 14 patients with primary anxiety plus secondary MDD; Group V: 26 normal controls. Modified Research Diagnostic Criteria (RDC) were used for diagnosis, based on the SADS interview. There was considerable overlap of SADS scaled scores between patient groups, which is consistent with a heterogeneous clinical presentation of depressive and anxiety states. REM latency was significantly shorter in patients with primary MDD (without anxiety) as compared with that in patients with primary anxiety (no MDD) and normals. Arecoline REM induction response time was significantly shorter in both primary affective groups (I and II) as compared with primary anxiety (no MDD) patients and normal controls. REM latency and arecoline REM induction time was not significantly different between the primary anxiety groups (III and IV) and normals. The study highlights the use of biological markers in differentiating between clinical syndromes confounded by mixed or overlapping phenomenology.     

Preliminary evidence for sleep complaints among children referred for anxiety

BACKGROUND AND PURPOSE: Clinical observation suggests that sleep complaints are common among youth with anxiety disorders though empirical data documenting this co-occurrence of symptoms are generally unavailable. PATIENTS AND METHODS: Based on retrospective chart reviews, the current study examined rates of several types of parent-reported sleep complaints among a sample of (n=35) purely anxious children and adolescents (ANX). Sleep complaints were examined in terms of age (children versus adolescents) and type of anxiety diagnosis (generalized anxiety versus other anxious diagnoses). Rates of sleep complaints among anxious youth also were compared to those among (n=38) healthy control children and (n=33) children referred for sleep problems. RESULTS: The presence of at least one intermittent sleep complaint was reported by 83% of parents of ANX, with almost half reporting at least one frequent sleep complaint. Rates of sleep complaints among anxious children versus adolescents were similar. Children with generalized anxiety disorder (GAD) had a significantly greater number of sleep complaints than children with other types of anxiety disorders, though rates for specific items varied. Although parents of sleep-referred children reported the highest rates of sleep complaints overall, the frequency of several specific types of sleep complaints was highly similar among ANX and sleep-referred children. CONCLUSIONS: Findings indicate that certain sleep complaints are common among ANX. The need for appropriate assessment practices is discussed.     

A high risk study of young children of parents with panic disorder and agoraphobia with and without comorbid major depression

Using family study methodology and psychiatric assessments by blind raters, this study tested hypotheses about patterns of familial association between anxiety and depressive disorders among high risk children of clinically referred parents. The study design contrasted five groups of children defined by the presence or absence in a parent of (1) panic disorder and agoraphobia (PDAG) without comorbid major depressive disorder (MDD) (n = 14); (2) comorbid PDAG plus MDD (PDAG + MDD) (n = 25); (3) MDD without comorbid PDAG (n = 12); (4) other psychiatric disorders (n = 23); and (5) normal comparisons (n = 47). While the PDAG and PDAG + MDD groups had similarly elevated rates of anxiety disorders and MDD, offspring of MDD parents had an elevated rate of MDD but not of anxiety disorders. Among children of parents with PDAG + MDD, the presence of an anxiety disorder did not significantly increase the risk for MDD in the same child. Thus, anxiety and MDD did not cosegregate among children of PDAG parents. These findings indicate that parental PDAG, either alone or comorbidly with MDD, increases the risk for both anxiety and depressive disorders in offspring. In the absence of PDAG, however, parental MDD does not appear to place children at risk for anxiety disorders. These findings are most consistent with the hypothesis that PDAG and PDAG + MDD share common familial etiologic factors while MDD alone is an independent disorder. More studies are needed to confirm these preliminary findings as well as to identify mediating factors that influence the transition from childhood to adult anxiety disorders.     

无望感-自尊理论对抑郁症、焦虑症、强迫症患者的适用性研究

目的:比较抑郁症、焦虑症、强迫症患者在归因方式、无望感、自尊上的异同,探索抑郁症、焦虑症、强迫症患者对无望感-自尊理论的适用性. 方法:对门诊或住院的抑郁症(n=81)、焦虑症(n=53)、强迫症(n=48)患者,及正常对照组(n=51)被试进行归因方式问卷、自尊量表的测评,得分进行4组间比较. 结果:①抑郁症组在...     

Are there gender differences in objective and subjective sleep measures? A study of insomniacs and healthy controls

It is well known that insomnia is more frequent in women than in men throughout all age groups. In this respect insomnia resembles other psychiatric disorders that occur more frequently in women such as anxiety and depressive disorders. Since insomnia is frequently a symptom of anxiety and depression, it remains an open question whether the comorbidity with psychiatric disorders fully explains the gender differences in the prevalence of insomnia or whether gender influences sleep independently from psychiatric conditions. We analyzed sleep measures of patients diagnosed with a primary insomnia (n=86) and of an age- and sex-matched healthy control group (n=86) by polysomnography; additionally, subjective rating scales were available for 70 patients and 54 controls matched for mean age and sex ratio. Surprisingly, none of the sleep continuity measures (sleep duration, sleep efficiency, arousal index, and wake%), nor slow wave or REM sleep % showed significant gender differences in both insomniacs and healthy controls. Also, subjective estimates of sleep quality were comparable in both sexes. As expected, insomniacs strongly differed from the control group in all subjective measures of sleep. Polysomnography showed significantly reduced sleep duration and efficiency, increased arousal index, and slightly, but significantly, less REM sleep in the insomniacs as compared to the healthy controls. These studies indicate that gender seems to have, if any, relatively little influence on sleep per se. We hypothesize that the clear gender differences in the prevalence of insomnia are caused predominantly by gender differences in the prevalence of anxiety and depression. Primary insomnia may be, at least in a part of the cases, a subclinical or subthreshold form of anxiety or depression.     

Long-term study of the sleep of insomnia patients with sleep state misperception and other insomnia patients.

OBJECTIVE: The objectives were 1) to investigate differences among patients with subjective insomnia (sleep state misperception), patients with objective findings of insomnia, and normal volunteers and 2) to assess the consistency of the sleep findings during a 2-month period. METHOD: Twenty-one subjects were studied. Subjects with sleep state misperception (N = 7) had insomnia complaints for more than 1 year, no objective sleep disturbance, and sleep efficiency of 90% or greater (on the diagnostic screening sleep recording), while subjectively estimating that sleep time was less than 6.5 hours. Subjects with objective insomnia (N = 7) met the same subjective criteria, but objectively sleep efficiency was 85% or less. Normal subjects (N = 7) had no insomnia complaints and objective sleep efficiency of 90% or greater. All subjects were recorded on 2 consecutive nights three times with a 3-week period between each pair of nights (6 standard all-night polysomnographic sessions of 8 hours). A subjective sleep questionnaire was administered after each sleep recording night. RESULTS: Sleep stage variables (percentages) were similar between the two insomnia groups, and both were different from the normal subjects. Sleep continuity variables were disturbed in the objective insomnia group, but they were similar in the sleep state misperception and normal groups. Both insomnia groups rated their sleep as inadequate on the questionnaires and differed from the normal subjects. The distinct sleep patterns of each of the three groups did not vary over the 6 nights of assessment. CONCLUSIONS: Sleep state misperception may be a prodromic or transitional state of sleep dysfunction between normal sleep and the sleep pattern of objective insomnia.