The Pittsburgh Sleep Diary

Increasingly, there is a need in both research and clinical practice to document and quantify sleep and waking behaviors in a comprehensive manner. The Pittsburgh Sleep Diary (PghSD) is an instrument with separate components to be completed at bedtime and waketime. Bedtime components relate to the events of the day preceding the sleep, waketime components to the sleep period just completed. Two-week PghSD data is presented from 234 different subjects, comprising 96 healthy young middle-aged controls, 37 older men, 44 older women, 29 young adult controls and 28 sleep disorders patients in order to demonstrate the usefulness, validity and reliability of various measures from the instrument. Comparisons are made with polysomnographic and actigraphic sleep measures, as well as personality and circadian type questionnaires. The instrument was shown to have sensitivity in detecting differences due to weekends, age, gender, personality and circadian type, and validity in agreeing with actigraphic estimates of sleep timing and quality. Over a 12-31 month delay, PghSD measures of both sleep timing and sleep quality showed correlations between 0.56 and 0.81 (n = 39, P < 0.001).

Automating the sleep laboratory: implementation and validation of digital recording and analysis

OBJECTIVES

We report on the implementation of digital processing in a large clinical and research sleep laboratory. The system includes the digital collection, display, analysis, and repository of physiological signals collected during sleep.

METHODS

After describing the original analog system, the computer equipment and software necessary for the digital implementation are presented and we explain our algorithms for rapid eye movement (REM) and delta-wave detection. Finally, we describe an experiment validating the digital system of display and analyses.

CONCLUSIONS

The digital processing of sleep signals saves computer operator, polysomnographic technologist, and computer time. It also saves resources such as polysomnographic paper and FM tape. The digital signals lend themselves to a large array of analysis techniques and result in improved signal quality. Automated REM and delta-wave detection via digital processing correlate highly with visual counts of rapid eye movements and delta waves.

Childbearing in women with and without a history of affective disorder. II. Electroencephalographic sleep

Electroencephalographic (EEG) sleep was examined longitudinally in 34 obstetrically healthy volunteers recruited early in pregnancy. All women were free of current psychiatric disorder. Fourteen women had a personal history of affective disorder, and 20 had no history of any psychiatric disorder. EEG sleep was recorded in subjects' homes at specified points from 12 weeks' gestation through 8 months' postpartum to examine the impact of childbearing on sleep and psychiatric symptoms in women with a history of affective disorder. EEG sleep measurements, as well as clinical ratings of sleep, indicated that sleep disturbances were most pronounced over the first 2 to 3 months' postpartum and were characterized primarily by interrupted sleep. The obstetrical course of these women was uneventful, and the outcome with respect to affective disturbances was highly favorable. Nevertheless, childbearing was associated with greater changes in total sleep time and with rapid eye movement (REM) latency reduction in women with a history of affective disorder, even in the absence of clinically significant mood changes. Findings suggest that the sleep system of women with a history of affective disorder may be more sensitive to the psychobiological changes associated with childbearing, as evidenced by earlier onset of sleep disruption over the childbearing course and a reduction in REM latency in the final trimester that persisted throughout the eighth postpartum month.

Childbearing in women with and without a history of affective disorder. I. Psychiatric symptomatology

Psychiatric symptoms and morbidity were examined prospectively in 34 obstetrically healthy volunteers recruited early in pregnancy. All women were free of current psychiatric disorder. Fourteen women had a history of affective disorder, and 20 had no lifetime history of any psychiatric disorder. Symptoms were assessed using both clinician- and self-administered ratings at specified points from 12 weeks of gestation through 8 months' postpartum. All women reported mild symptom elevation during pregnancy and the early puerperium, regardless of psychiatric history. The most frequently endorsed symptoms in both groups were somatic. However, women with a history of affective disorder reported more psychic and somatic distress than women with no psychiatric history. Onset of a psychiatric disorder did not occur during pregnancy in this sample, and only one woman, with both a personal and family history of affective disorder, met criteria for a new episode postpartum. Brief periods of symptom elevation occurred postpartum for 14.7% of the sample (five women, two with and three without a personal history of affective disorder) in the context of additional life stressors combining with the stress of new motherhood. These findings suggest that the impact of childbearing alone on psychiatric symptoms and morbidity is modest among women who are psychiatrically healthy at pregnancy onset and have sound social support networks.

Concordance between habitual sleep times and laboratory recording schedules

The validity of laboratory-based studies of sleep depends, in part, upon good concordance between habitual sleep schedule and laboratory recording schedule. Without good concordance, error variance due to the circadian misplacement of sleep and to different amounts of time in bed is probable. In an assessment of scheduling concordance in 1,762 research patient nights over two time intervals, we observed good concordance (< 30-minute discrepancy) in 71.2-77.3% of bedtimes and waketimes, discrepancy (difference of > or = 30 minutes) in 14.9-24.2% of bedtimes and waketimes, and missing data in 4.6-7.5% of times. Waketime differences were consistently in the direction of earlier laboratory than habitual waketimes, whereas differences in bedtime were about equally divided between earlier and later (laboratory vs. habitual). Subjects with schedule discordance averaged 19.5 minutes less time in bed during laboratory sessions as compared with their habitual sleep schedule, whereas subjects with schedule concordance averaged only 3.6 minutes less (p < 0.001). Our experience suggests that it may be more difficult to achieve higher rates of concordance among young adult and middle-aged subjects than among elders and that patient requests related to external constraints on scheduling were a frequent reason for discrepancy. We strongly recommend a policy of routinely including data on laboratory versus habitual sleep times in peer-reviewed publications.

Subtyping DSM-III-R primary insomnia: a literature review by the DSM-IV Work Group on Sleep Disorders

OBJECTIVE

The authors review the usefulness, reliability, and validity of recently proposed subtypes of primary insomnia. DSM-III uses "primary insomnia" to indicate chronic insomnia not associated with other diagnosable mental or medical disorders, whereas the International Classification of Sleep Disorders (ICSD) recognizes three subtypes: psychophysiological insomnia, idiopathic insomnia, and sleep state misperception.

METHOD

After reviewing all of the primary source references for each insomnia disorder in the ICSD and all of the additional primary sources cited in each of these, the authors conducted an automated literature search using Medline. Of the 48 primary sources located, the authors selected 27 studies that were reported in peer-reviewed journals, had the largest available subject groups, used diagnostic reliability procedures, and included control groups.

RESULTS

The studies reviewed contained limited empirical support for the proposed distinction between idiopathic and psychophysiological insomnia. Sleep state misperception appears, however, to be a highly prevalent feature of chronic insomnia generally, rather than only a specific disorder per se.

CONCLUSIONS

The authors conclude that there is not yet sufficient empirical evidence to warrant the abandonment of DSM-III-R "primary insomnia" and the adoption of the ICSD subtypes in DSM-IV. However, they affirm the heuristic value of the ICSD subtypes and the need for field trials to compare the performance characteristics of the DSM-III-R and ICSD systems with respect to 1) interrater reliability, 2) effects of rater expertise (generalist versus specialist) on rates of agreement, and 3) effects of polysomnographic data on rates of agreement.

Sleep, gender, and depression: an analysis of gender effects on the electroencephalographic sleep of 302 depressed outpatients

Gender-related differences in electroencephalographic (EEG) sleep were examined in 151 pairs of men and women with major depression, all outpatients, matched for age and severity of depression. Across five decades (age 21-69), depressed men had less slow-wave sleep than did depressed women. Gender differences were small with respect to visually scored measures of slow-wave sleep time and percent, but moderate for gender differences in automated measures of slow-wave density. The time constant of the polygraph preamplifier significantly affected both visually scored and automatically scored slow-wave sleep. Other measures such as REM sleep latency, first REM period duration, sleep efficiency, and early morning awakening, showed robust age effects, but no main effects for gender or gender-by-age interactions. Gender effects on slow-wave sleep and delta-wave counts in depression parallel gender effects seen in healthy aging. The possibility of occult alcohol use by depressed male outpatients cannot be definitely excluded as a partial explanation of the current findings. However, covarying for past alcohol abuse did not negate the statistical significance of the observed gender effects on slow-wave sleep and delta-wave density. The possibility of gender differences in slow-wave regulatory mechanisms is suggested, but similarity in temporal distribution of delta-wave density between the first and second non-rapid-eye-movement (NREM) periods does not support gender differences in slow-wave sleep regulation.

The effects of prenatal alcohol and marijuana exposure: disturbances in neonatal sleep cycling and arousal

Neonatal EEG and sleep findings are presented from a longitudinal study of the effects of maternal alcohol and marijuana use during pregnancy. Infant outcome has been examined relative to the trimester(s) of pregnancy during which use occurred. Disturbances in sleep cycling, motility, and arousals were noted that were both substance and trimester specific. Alcohol consumed during the first trimester of pregnancy was associated with disruptions in sleep and arousal, whereas marijuana use affected sleep and motility regardless of the trimester in which it was used. Although these findings are preliminary and based on a small sample of women exhibiting only moderate substance use during pregnancy, they do suggest that specific neurophysiological systems may be differentially affected by prenatal alcohol or marijuana exposure even in the absence of morphological abnormalities.

Electroencephalographic sleep of healthy children. Part II: Findings using automated delta and REM sleep measurement methods

Using earlier developed computer-based measurement methods, delta and REM activity were examined during sleep as a function of age, gender, and time of night in 85 healthy, 6- to 16-year-old children. Chronological age was found to account most strongly for differences in automated delta and REM count measures in this age range. Increasing age was shown to be associated with a significant decline in both automated measures, but the effect was much greater for the delta count measure. The age-related decline in delta wave activity was reflected primarily in a linear decline in 2.0-3.0 Hz delta activity, that is, in the faster end of the delta frequency band. Examination of these measurements in successive NREM and REM sleep periods confirmed that, in children as in adults, delta activity decreases and REM activity increases across the night. Findings are discussed relative to those obtained in the same children using standard measurement methods.

Electroencephalographic sleep of younger depressives. Comparison with normals

The electroencephalographic sleep of younger depressives (aged 20 to 44 years) was compared with that of an age-matched group of normals. The patients demonstrated many of the typical sleep changes reported for older depressed populations: shortened rapid-eye-movement (REM) latency; REM sleep activity alterations, with a shift to the early portion of the night (first REM period); reduced delta sleep; and sleep efficiency reductions marked by sleep-onset difficulties. The traditional scoring procedures were supplemented by automated REM and delta-sleep analyses that provided more precise delineation of these differences between patients and normals, particularly the distributions of REM activity and delta-wave patterning.

"Paradoxical" shortening of REM latency on first recording night in major depressive disorder: clinical and polysomnographic correlates

Among 92 inpatients with major depressive disorders, variability in REM latency (RL) during the first two recording nights was assessed by means of an "adaptation coefficient" (AC = night 1 RL--night 2 RL X 100 divided by mean RL for nights 1 and 2). Although mean RL was very similar for both nights (48.1 and 50.7 min), individual ACs showed a gaussian distribution [range: -176.5-171.4; mean: -1.2 (67.3); median: -4.4]. Forty-two patients (45.7%) exhibited shortening of RL on night 2 compared with night 1 (positive AC, corresponding to an "expected" evolution), 48 patients (52.2%) displayed the opposite pattern (negative AC, corresponding to a "paradoxical" evolution), and two patients had identical values on both nights. Extent of increase in RL from first to second night (i.e., extent of "paradoxical" evolution) correlated significantly with increasing duration of current episode, earlier age of onset, and poorer clinical response to tricyclic antidepressants. A cutoff AC of -7 correctly classified 62% of patients according to treatment response. The research diagnostic criteria-based retarded subtype of depression was associated with a more negative AC (i.e., a more "paradoxical" evolution), and the situational subtype was associated with a more positive AC (i.e., a more "expected" evolution) than the remainder of the sample. The subgroup with the most negative ACs (i.e., largest increases in RL from first to second night) also had longer sleep latencies, whereas the subgroup with the most positive ACs (i.e., largest decreases in RL) had higher REM activity and REM density as compared with the remainder of the sample. These results suggest that RL in major depression is not a static parameter and that the study of its within-subject variability can be helpful for diagnostic confirmation and prediction of treatment response.

Comparison of effects of desipramine and amitriptyline on EEG sleep of depressed patients

Despite their widespread use, there are few data concerning the effects of tricyclic antidepressants on EEG sleep in depression. The present study documented the effects of desipramine (DMI, n = 17) and amitriptyline (AT, n = 16) upon EEG sleep in hospitalized depressed patients as part of a double-blind protocol involving 28 days of active treatment. Compared to placebo, patients receiving DMI showed somewhat worsened sleep continuity, particularly after 1 week of administration when the dose was 150 mg/day. On the other hand, sleep architecture and REM measures showed a rapid suppression of REM sleep, and then partial tolerance for this effect was observed with continued administration of DMI for 3 weeks. DMI was a more potent suppressor of REM sleep, while AT was more sedative. Based on these differences in effects upon EEG sleep, a discriminant function was derived and resulted in a correct classification of 87.5% of AT cases and 76.5% of DMI cases. These results are discussed in terms of the differences in pharmacological profiles for uptake blockade and anticholinergic potency for these two compounds.

Depression in borderline patients: a prospective EEG sleep study

The relationship between borderline personality disorder and primary major depression was studied prospectively using Schedule for Affective Disorders and Schizophrenia-Lifetime Version (SADS-L) interviews and electroencephalographic (EEG) sleep studies. Ten consecutively admitted borderline patients (a prospective sample), defined by Gunderson's Diagnostic Interview for Borderlines (DIB), underwent EEG sleep studies on two consecutive nights and were compared to previously reported samples of nonborderline depressed patients (defined by Research Diagnostic Criteria; RDC), normal controls, and DIB-defined borderline patients who had been referred "to rule out major depression" (a retrospective sample). EEG sleep data were analyzed visually and by automated techniques. Rapid eye movement (REM) latency values were similar in depressed and both borderline groups but significantly different from controls. Eighty-five percent of REM latency values in RDC major depressives were less than or equal to 65 minutes, compared to similar rates of 75% in the prospective sample of borderline patients and 65% in the retrospective sample, versus 35% for controls (chi 2 = 10.7, p less than 0.005). The REM latency in borderline patients did not vary with the severity of depression as measured by the Hamilton Rating Scale for Depression. In the prospective borderline sample, the major SADS-L diagnoses were chronic intermittent depression (five), current major depression (four) (two unipolar, two bipolar II), and labile personality (one). A convergence of nosologic and EEG sleep data is suggested, and supports the concept of a close relationship between criteria-defined borderline personality disorder and affective illness.

Application of automated REM and slow wave sleep analysis: I. Normal and depressed subjects

Computerized analysis of rapid eye movement (REM) and delta electroencephalographic (EEG) sleep patterns in normal and depressed subjects offers opportunities to examine sleep more precisely than previously possible. In the present study, automated REM analyses demonstrated good reliability with traditional manual procedures in both normal and depressed subjects. However, automated delta analyses correlated well with traditional scoring in normal subjects, but not in depressed patients. These findings suggest the use of automated delta techniques similar to those employed in this report or spectral analytic techniques in the following types of studies: specificity of delta sleep in various psychiatric syndromes, changes in delta sleep produced by the administration of psychotropic agents, relationships between delta sleep and sleep-related neuro-endocrine patterns, and, finally, relationships between delta sleep patterns and other biological rhythms such as activity and temperature.

Application of automated REM and slow wave sleep analysis: II. Testing the assumptions of the two-process model of sleep regulation in normal and depressed subjects

Abnormalities in a two-process model of sleep regulation (a sleep-dependent process, termed Process S, and a sleep-independent circadian process, termed Process C) have been proposed to account for sleep abnormalities in depressive states. The major tenets of the two-process model of sleep regulation as applied to depression are: the level of process S, as reflected by the electroencephalographic (EEG) slow-wave activity, corresponds to the sleep-dependent facet of sleep propensity; the pathognomonic changes of sleep in depressives are a consequence of a deficiency in the build-up of process S. The application of automated rapid eye movement (REM) and delta wave analyses in normal subjects and younger depressed patients supports the model to some extent: The time spent asleep is positively correlated with total delta waves (normals and depressives) and average delta waves (depressives); delta sleep is lower in depressives than in normals; the average delta wave count is significantly reduced in younger depressives over the total night and in non-REM period 1. The model also postulates that measures of phasic REM activity are inversely related to process S, suggesting that process S can be regarded as exerting an inhibitory influence on phasic REM activity.

EEG sleep of normal healthy children. Part I: Findings using standard measurement methods

Despite the increasing application of all-night electroencephalographic (EEG) sleep studies to children for clinical as well as for research purposes, readily available normal EEG sleep standards for the period of childhood have remained sparse and, at present, reflect data on only approximately 100 children 6 to 16 years of age. As part of a large scale study examining various aspects of EEG sleep among children, findings derived using standard recording and scoring methods are reported for a new sample of nearly 100 normal, healthy children and are compared with existing standards. Data obtained add substantially to the existing database and generally confirm findings of previous normative reports on children in this age range.

Differential effects of amitriptyline and of zimelidine on the sleep electroencephalogram of depressed patients

The effects of amitriptyline (n = 14) or zimelidine (n = 13) on the sleep electroencephalogram of hospitalized depressed patients were assessed in a double-blind protocol involving 28 days of active dosing. Zimelidine induced no immediate improvement in sleep continuity, and even after 3 wk on zimelidine subjects tended to have longer sleep latency, more awakenings, and lighter non-rapid eye movement (REM) sleep than before taking the drug. Zimelidine did, however, induce a rapid and persistent alteration of sleep architecture and selected REM measures. REM sleep, which was suppressed over the first two nights on zimelidine, was maximally suppressed after 1 wk, but by 3 wk there was some tolerance for selected REM measures. While zimelidine induced none of the sedative effects of amitriptyline, both were equivalent in their REM-suppressant effects. These findings are discussed in terms of the differences in uptake blockade and anticholinergic potency in these two drugs.

Depressive psychopathology in male sleep apneics

Depression has been reported to be frequent in sleep apnea syndromes. In a sample of 25 consecutive male sleep apneics, 40% met Research Diagnostic Criteria for an affective disorder or for alcohol abuse. A multiple regression analysis indicated that 61% of the variance in depression ratings could be explained by four variables: age, REM activity, REM latency (square root), and presence or absence of antihypertensive medications (multiple R = 0.78). The use of these variables in a discriminant function analysis correctly predicted the membership of 68% of the sample in either a low or high depression group (kappa = 0.44; p less than .01). These findings are reviewed in relation to other research on age-related sleep changes and vulnerability to depression.

Persistent psychophysiologic insomnia: preliminary Research Diagnostic Criteria and EEG sleep data

Some patients with persistent psychophysiologic insomnia have a history of generalized anxiety, minor depression, or drug misuse. Their sleep resembles sleep of patients with generalized anxiety (except for night 2 improvement in the insomniacs' sleep continuity) but differs from sleep of patients with major depression.

EEG sleep evaluation of depression in borderline patients

In this study the sleep of borderline patients and patients with primary nondelusional depression showed sleep continuity disturbance and greater REM activity and density (particularly during the first REM period) than that of normal control subjects. First-night REM latencies were more variable in the borderline than in the depressed group, but by the second night both groups showed shorter REM latencies than the controls. The similarities in EEG sleep suggest a relationship between borderline disorder and the affective spectrum and cast doubt on the definition of the borderline disorder as a pure character type.

Multiple Sleep Latency Test findings in Kleine-Levin syndrome

Multiple Sleep Latency Test (MSLT) findings in a case of Kleine-Levin syndrome are reported for the first time. MSLT data indicate sleepiness as severe as in narcolepsy or obstructive sleep apnea and the occurrence of four sleep onset rapid eye movement (REM) periods, with a greater REM propensity at 2:00 p.m. and 4:00 p.m. than at 10:00 a.m. and 12:00 noon. The replication of such findings might suggest that Kleine-Levin syndrome could be considered a form of periodic REM sleep disinhibition. Therefore, the traditional hypothesis of diencephalic dysfunction may require modification to include the role of more caudal brain stem structures specifically activated during REM sleep.

REM latency in depression: is there one best definition?

The concurrent validity of different definitions of REM latency has been tested by comparing the ability of each definition to discriminate between primary depressives (outpatients and inpatients) and normal controls. In outpatients the percentage of cases correctly identified ranged from 62.5% to 70.8%; in inpatients, from 64.6% to 70.8%. REM latency definitions with the least stringent sleep-onset criteria yielded the lowest specificity. In contrast, the range of sensitivities yielded by different definitions was narrower and not clearly affected by sleep-onset criterion or exclusion/inclusion of wakefulness between sleep onset and first REM period. Furthermore, different definitions of REM latency correlated equally well (p less than 0.01) with Hamilton depression ratings. The shorter REM latencies in both outpatients and inpatients were associated with a later time of NREM sleep onset than in controls, rather than with an earlier REM sleep-onset time.

Sleep in narcolepsy and depression. Does it all look alike?

Depression has been reported to be frequent in narcolepsy and has been considered to be variously a reaction to chronic sleepiness or an endogenous expression of the pathophysiology of narcolepsy. Supporting the latter possibility are reports of similarities between the nocturnal rapid eye movement (REM) sleep of narcoleptics and inpatients with endogenous depression. In a comparison of 25 consecutive narcoleptics and 25 age-matched outpatient primary depressives, significant group differences were found in nocturnal EEG sleep measures of sleep continuity, sleep architecture, and REM sleep. Twenty per cent of the narcoleptic sample met Research Diagnostic Criteria (RDC) for a past history of major or chronic intermittent depression, but 60 per cent did not meet RDC criteria for any present or past psychiatric disorder. These findings mandate a cautious reevaluation of the nature of depressive symptoms in narcolepsy and leave open the question of whether there are common neurobiological control mechanisms in narcolepsy and depression.

Reduced cortisol latency in depressive illness

Depressed patients commonly have disturbances in their sleep and cortisol secretory patterns. When the sleep-related changes in plasma cortisol concentration were measured in 14 patients with a primary major depressive illness, they differed significantly from the changes measured in 14 age- and sex-matched healthy control subjects. The nadir of the nocturnal plasma cortisol concentration was significantly greater in the group of depressed patients, and the nocturnal increase in the plasma cortisol concentration occurred significantly closer to sleep onset in these patients. The circadian activity within the hypothalamic-pituitary-adrenal axis of these depressed patients showed a subtle but significantly disturbed temporal relationship to sleep onset. This reduced time between sleep onset and the nocturnal increase in cortisol secretion suggests a possible biologic correlate of a depressive illness that might be useful as an illness marker in depressed patients.

EEG sleep in outpatients with generalized anxiety: a preliminary comparison with depressed outpatients

To develop further perspective on the psychophysiology of generalized anxiety disorder and primary depression, all-night electroencephalographic (EEG) sleep measures in outpatients with diagnoses of generalized anxiety disorder and primary (nondelusional) depression were compared. Both groups had difficulty initiating and maintaining sleep, and diminished amounts of slow-wave sleep. Compared to patients with generalized anxiety disorder, depressives had a shorter rapid eye movement (REM) latency, greater REM sleep percent and eye movement activity, and a different temporal distribution of REM sleep. Anxious patients showed few changes from first to second night, whereas depressives showed increases in several REM sleep indexes. The combination of REM sleep latency and REM percent correctly classified 86.7% of patients. These data may provide a more direct measure of central nervous system arousal and sleep/wake function than previous studies in the psychophysiology of anxiety. They also lend support to the clinical distinction between generalized anxiety disorder and primary depression and to the classification of anxiety states as disorders of initiating and maintaining sleep.

EEG sleep, depression, and aging

To date little attention has been paid to the possible age-dependent relationships of EEG sleep measures in depression or to the implications of such relationships for diagnostic sensitivity and specificity. In a study of 108 patients with major depressive disorders (67 inpatients, 41 outpatients), age was shown to be a very powerful determinant of electroencephalographic (EEG) sleep patterns. Thus, among other sleep variables, sleep efficiency, delta sleep percent, and REM latency all showed significant linear declines with increasing age. Similar trends were seen in both inpatients and outpatients. Some variables were without age trends (age-stable), including sleep latency, REM sleep percent, and REM activity. These findings confirm those of an earlier report from our laboratory [45] and suggest that age-corrected sleep variables can be developed for clinical diagnostic application. Thus, using normative data from Gillin et al. [19] for comparison, a sensitivity level of 65% for age-corrected REM latency was demonstrated, together with a specificity of 95% and a diagnostic confidence of 92%. Data from a pilot study comparing EEG sleep measures in depression and dementia are also presented; these data suggest the potential utility of EEG sleep measures in the differential diagnosis of these two disorders, especially in patients with mixed symptoms. Additional areas for further research are reviewed with enumeration of specific testable hypotheses.

Prevalence of sleep apnea and nocturnal myoclonus in major affective disorders: clinical and polysomnographic findings

We performed screening polysomnography on 86 inpatients with affective disorders and found that 13 (15.1 per cent) had sleep apnea and one had nocturnal myoclonus. The apnea tended to be extremely mild, with an average of 27.8 episodes per patient and with a mean duration of 15.0 seconds. No clinically significant cardiac arrhythmia accompanied the apnea. The apnea was predominantly obstructive or mixed, not central. Only four patients (4.7 per cent) had apnea indices greater than five, and even here the total apnea was considered mild. Much of the apnea (68.3 per cent) occurred during rapid eye movement sleep. While there was no association of apnea with gender or with type of sleep-wake complaint, a significant relationship with age emerged. On the basis of these data, we suggest that routine polysomnographic screening for sleep apnea and nocturnal myoclonus in affective disorders is not indicated. On occasion, however, both an affective disorder and a sleep-apnea syndrome co-exist in the same patient. In such cases, the sleep-wake complaint is usually very prominent and/or long-standing in relation to other psychopathology and requires appropriate polysomnographic evaluation.

Application of automated REM analysis in depression

Application of automated rapid-eye-movement (REM) analysis can characterize individual REM periods in depressed patients. Average REM count for the individual REM periods generally demonstrated considerable decreases in the second half of the REM period and differentiated patients who subsequently did not respond well to tricyclic antidepressants. These findings suggest that, even as late as six hours into a night of sleep, significant differences among depressed patients are present, based on treatment responder groups. Furthermore, a reevaluation of the previous emphasis on REM abnormalities in the first hour or two of the night may be indicated.

Nortriptyline and EEG sleep in depressed patients

The effect of nortriptyline was assessed on the EEG sleep of 20 inpatients with major depressive syndrome. While 25 mg of nortriptyline had an immediate effect on REM sleep variables, relatively little influence on sleep continuity measures was noted. Subsequent administration of 75 and 100 mg of nortriptyline produced continued REM sleep suppression over several weeks. In summary, nortriptyline altered EEG sleep in a pattern similar to that of amitriptyline. REM latency and REM sleep time were consistently reduced by drug administration, while REM activity was only transiently altered as with amitriptyline. The comparison with amitriptyline showed, for the most part, similar influences on REM sleep without the sedative effects of amitriptyline.

Application of the multiple sleep latency test in disorders of excessive sleepiness

Multiple sleep latency tests were performed in 42 drug-free outpatients with excessive sleepiness: 12 narcoleptics, 9 sleep apneics, 7 primary depressives, and 14 patients with miscellaneous disorders. Among-group comparisons were made by one-way ANOVA for each nap (time-of-day effect) and using four-nap means of EEG sleep variables. Four-nap means were significantly different among groups for percent awake, percent time spent asleep, stage 1 latency, and REM latency. Of 22 significant pairwise comparisons (P less than 0.05, LSD test), 77.3% occurred at 12.00 and 14.00. Depressives showed lower sleep percentage (more arousal) and fell asleep later than narcoleptics or apneics. Patients with miscellaneous disorders occupied a middle position. Sleep percentage was gradually reduced during the day in depressives but remained high or rose further in apneics, narcoleptics, and miscellaneous patients. Naps were SOREMP-positive (sleep onset REM) 60.4% of the time in narcoleptics, 25.0% in apneics, 3.5% in depressives, and 5.4% in miscellaneous patients. SOREMP distribution across naps (10.00, 12.00, 14.00 and 16.00) was 19%, 31%, 19% and 31%, respectively. REM latency was significantly shorter in narcolepsy than in apnea. In summary, results show a continuum of excessive daytime sleepiness (EDS), demonstrating MSLT application in the differential diagnosis of EDS and significant diurnal variation in sleep measures.

Electroencephalographic sleep findings in depressed outpatients

We compared the electroencephalographic (EEG) sleep characteristics of 20 outpatients with those of 20 age-matched inpatients with major primary depressive disorders. Both groups showed similar patterns of sleep disturbance: reduced rapid eye movement (REM) sleep latencies, sleep efficiencies, and slow wave sleep. While the inpatients had greater REM activity in the first REM period than did the outpatients, both groups showed evidence of greater REM sleep time and REM activity during the first half of the night than do normals. The outpatients demonstrated a level of adaptation in that more REM sleep time and activity were present on night 2 than on night 1.

EEG sleep and tricyclic blood levels: acute and chronic administration in depression

An understanding of the effects of antidepressants on sleep can be aided by determinations of tricyclic plasma levels in relationship to sleep. Previous studies have been established that steady state plasma levels of amitriptyline relate to certain aspects of rapid eye movement (REM) sleep. The present investigations attempt to replicate the REM sleep/tricyclic plasma level relationships in a larger group of psychiatric hospitalized patients for depression and to study whether such relationships persist in a group of ambulatory patients studied longitudinally for 1 to 2 years. In an acute treatment study of 38 patients, REM sleep percent and average REM activity demonstrated a significant relationship with plasma levels, even when controlled for age and severity. The sleep-plasma level relationships seem more prominent with amitriptyline levels than with nortriptyline plasma levels. In a long term comparison of plasma levels, tricyclic plasma levels showed a significant correlation with REM latency, REM percent and average REM activity. Thus, it appears that changes in REM sleep such as REM suppression correlate significantly with tricyclic plasma levels both on a short (4 weeks) and long term basis (1 to 2 years). The implications of these findings are discussed.

Neuropsychological assessment and EEG sleep in affective disorders

The neuropsychological test performance of 76 hospitalized, depressed patients meeting RDC for the presence of affective disorder was assessed as part of a protocol involving amitryptyline (n = 53) or placebo (n = 23). Tests included the Trail-making Test (TMT), the Benton Visual Retention Test, and the Shipley-Hartford Scale. Clinical ratings and data concerning the characteristics of EEG sleep were also obtained. Analysis of data collected after a drug-free period of 2 weeks and again at the end of the protocol yielded the following conclusions. Base-line performance was inferior to norms for these tests, but for the TMT, scores were not as poor as that expected for brain-damaged patients. Poor performance was often associated with older age, the presence of psychotic features, and prolonged sleep latencies. Baseline Hamilton Rating Scale (HRS) was predicted best by TMT part B. However, this association was not as strong as that between HRS and poor sleep efficiency. Treatment with drug or placebo had little differential effect upon test performance over the course of the protocol. It is suggested that further research should utilize tests which have specificity in localizing cerebral lesions, so that any focal deficits in brain function in depression might be identified.

REM sleep, naps, and depression

Continued interest in rapid eye movement (REM) sleep abnormalities in depression stimulated comparative studies on daytime naps versus nighttime sleep. In a group of 15 depressed patients, REM latencies in morning and afternoon naps were similar to the shortened REM onset at night. Although REM latency did not vary across the three times, the propensity for REM sleep appeared to be greater in the morning nap than in the afternoon nap and the early portion of nocturnal sleep. Finally, the data suggest that responders to tricyclic treatment tend to be poor sleepers during daytime naps.

Diagnostic classification of sleep disorders: implications for psychiatric practice

We have applied a diagnostic classification of sleep and arousal disorders (Association of Sleep Disorders Centers - ASDC) to a group of 174 patients in order to assess its usefulness. In our population, there were over twice as many disorders of initiating and maintaining sleep (DIMS) as there were disorders of excessive sleepiness (DOES). We found that 68.1% of diagnoses in DIMS were psychiatric (particularly affective disorders) and that 37.8% of diagnoses in DOES were either sleep apnea or narcolepsycataplexy. Furthermore, drug/alcohol abuse was much more strongly associated with DIMS, while medical disorders were more often found to be associated with DOES. Since only 58% of our sample could be adequately classified with one diagnosis, we expect that the ASDC nosology will need to evolve further. Nevertheless, the nosology should facilitate comparability and pooling of data across centers.

Distribution of REM latency in depression

While shortened REM latency is now considered the most consistent sleep feature observed among patients suffering from primary depressive episodes, and one which has generated a variety of hypotheses regarding possible mechanisms, few studies have employed long-term longitudinal designs. In the present investigation, REM latency was examined in 22 hospitalized depressed patients who were studied nightly during a 5-week protocol were bimodally distributed medication during that period; REM latencies were bimodally distributed with peaks occurring shortly after sleep onset and again 30-40 min later. Very short REM latencies (less than or equal to 20 min) were neither uncommon nor isolated events and persisted over time in this patient sample. These findings are discussed in relation to findings on shortened REM latency in other study populations.

Sleep and treatment prediction in endogenous depression

The prediction of clinical response in depression has been based primarily on clinical symptoms and history. Recently, psychobiologic measures have been used to increase the accuracy of clinical prediction. In 34 drug-free patients with primary endogenous depression treated with amitriptyline, the application of EEG-monitored sleep criteria alone was more significant than clinical status alone in the prediction of clinical response. Prolonged REM latency and reduced difficulty in sleep onset following the administration of amitriptyline were the main sleep variables contributing to this prediction equation. These data suggest a strong relationship between clinical outcome and psychobiologic profile in patients with endogenous depression after a "pharmacologic probe" with a tricyclic antidepressant.

MHPG excretion and EEG sleep in primary depression

Measures of daily urinary 3-methoxy-4-hydroxyphenylglycol (MHPG) excretion and electroencephalographic (EEG) sleep data were examined in 30 patients hospitalized for depression. This sample (mean age = 35 years) comprised 17 females and 13 males, all of whom were drug-free for 2 weeks and met Research Diagnostic Criteria for primary depressive disorder. Data analyses were conducted on the entire group, as well as the male, female, unipolar, and recurrent subgroups. No significant relationships were observed between total MHPG excretion and rapid eye movement (REM) or non-REM sleep variables. In particular, the absence of an interrelatedness of MHPG and REM sleep fails to confirm earlier findings in a smaller patient sample. These results, therefore, raise new questions about the proposed role of central noradrenergic activity in the mediation of REM sleep in depression.

EEG sleep alterations in olivopontocerebellar degeneration

All-night polygraphic recordings of the electroencephalogram, horizontal electrooculogram, and submental electromyogram were performed in two patients with familial olivopontocerebellar degeneration. Sleep was characterized by subnormal measurements of both rapid eye movement (REM) and delta (slow-wave) sleep. Phasic eye movements were reduced out of proportion to tonic components of REM sleep. These findings lend further support to theories linking the pontine nuclei to the primary regulation of sleep in both experimental animals and humans.

Sleep disturbances in a series of elderly patients: polysomnographic findings

A group of 27 elderly patients with complaints of either chronic insomnia or excessive daytime sleepiness were studied in the Sleep Evaluation Center of Western Psychiatric Institute and Clinic during the period January 1977-June 1979. On the basis of anamnestic data from patients and bedroom partners, together with polysomnographic findings, sleep disturbances were classified according to the nosology of the Association of Sleep Disorders Centers. Of the 27 patients, 19 had disorders of initiating or maintaining sleep (DIMS), 7 had disorders of excessive somnolence (DOES), and 1 had parasomnia (episodic nocturnal wandering). Of the 19 DIMS patients, two-thirds had either a primary affective disorder (depression) or a persistent psychophysiologic disturbance. Of the 7 DOES patients, 6 had a primary sleep disorder such as a sleep apnea syndrome or narcolepsy-cataplexy. Additional electroencephalographic sleep data are presented on elderly patients with primary nonpsychotic depression. The latency of rapid eye movements (REM) in the depressed patients was shorter (p less than 0.05) than in patients with a persistent psychophysiologic disturbance. The percentage of REM sleep was significantly elevated (p less than 0.05) in the depressed group, and intermittent wakefulness was decreased (p less than 0.01). The causes of sleep disturbance in the elderly are both heterogeneous and complex. The need for accurate differential diagnosis and a multiaxial approach is stressed.

EEG sleep and affective psychosis

EEG sleep changes in delusional depression have been reported previously but no attempt has been made to examine sleep profiles among specific delusional subtypes. In 29 psychotically depressed patients, those patients with delusions of guilt or sin demonstrated both increased sleep discontinuity and decreased REM sleep, especially during the first REM period, while patients with somatic delusions showed increased REM activity, especially in the first REM period. The implications of these findings are discussed.

Changes in weight during treatment for depression

Changes in appetite and weight were examined in a group of 47 carefully diagnosed primary depressives who were treated in a random design with either placebo (N = 17) or amitryptyline (N = 30) over a 35-day protocol. While the amitriptyline treated group as a whole showed a greater gain in weight than did the placebo group (4.5 vs. 0.5 lb, p less than 0.05), no differential effects could be demonstrated between drug responders and nonresponders. Likewise, while a consistent relationship between the self-report of decreased appetite and final weight change was noted in the placebo group, no simple relationship between final weight change and self-reported changes in appetite were apparent in the drug-treated patients. There was, however, a relationship between the report of decreased appetite and clinical severity of depression in the drug nonresponder subgroup despite significant weight gain during the protocol. Thus, weight change during this study period did not appear to show a simple relationship to corresponding clinical change. The clinical lore that has supported the notion that increased appetite and weight gain in patients being treated with tricyclic antidepressants are "good" signs cannot be confirmed by our findings.

EEG sleep and affective psychoses: I. Schizoaffective disorders

The sleep electroencephalogram (EEG) was studied in 41 depressed inpatients. EEG sleep records were compared for two diagnostic subgroups; patients with psychotic depression (n = 29) or with schizoaffective disorders (n = 12). As was true in the previous pilot study, no major EEG sleep variables distinguished the patients with psychotic depression from those with schizoaffective disorders. These data are consistent with the theory that all psychotic depressive states may have certain common psychobiologic features such as shortened rapid eye movement (REM) sleep latency.

EEG sleep in primary depression. A longitudinal placebo study

Characteristic EEG sleep changes in depression are highlighted by a sleep continuity disturbance, delta sleep reduction, and a shortened REM latency. Since these findings have been derived primarily from only a few baseline recordings, questions regarding their persistence and/or variability have not been previously addressed. As part of an extensive set of investigations of EEG sleep in depression, we examined nightly the sleep of 12 hospitalized, non-delusional, primary depressives who were involved in a program of active psychosocial treatment intervention and received only placebo during a 5-week study period. EEG sleep findings revealed a relative lack of change across time, particularly in those parameters reported to be associated with a primary or 'biologic' depressive episode. While some degree of clinical improvement was noted, the group failed to achieve a state of remission or even partial remission as determined by the Hamilton Rating Scale. It appears that the major sleep alterations associated with such disorders persist for up to at least 5 weeks in the absence of pharmacologic or other somatic intervention.

Electroencephalographic sleep recordings and depression in the elderly

Eighteen patients over the age of 60 who were experiencing a major depressive episode were studied on a Clinical Research Unit after they had been drug-free for at least two weeks. All-night electroencephalographic (EEG) recordings revealed considerable fragmentation of sleep, a mean sleep efficiency of 58 percent, and very little delta sleep. The findings of reduced sleep time, shortened REM latency, and high REM density were similar to those in depressed patients under the age of 60. These preliminary findings support the application of EEG sleep recordings as a tool for the differential diagnosis of depression in the elderly.