Protecting sleep quality in later life: a pilot study of bed restriction and sleep hygiene.

We tested two interventions for improving sleep consolidation and depth in normal elderly participants: a modification of sleep-restriction therapy and sleep-hygiene education. Twenty-one elderly participants without sleep disorders were randomized to sleep hygiene plus bed restriction (i.e., restricting time in bed by 30 minutes nightly for one year) or to sleep hygiene alone. Participants in the bed-restriction group showed a median increase in sleep efficiency of 6.1% versus 1.8% in participants receiving sleep hygiene instruction, and an increase in allnight delta EEG power. Self-reported mood on awakening in the morning showed greater improvement over the first eight weeks in the sleep-hygiene condition. The use of sleep hygiene was associated with initial improvement in daytime well-being, whereas bed restriction led to sustained improvements in sleep continuity and sleep depth.

Maintenance nortriptyline effects on electroencephalographic sleep in elderly patients with recurrent major depression: double-blind, placebo- and plasma-level-controlled evaluation.

Our aim was to contrast the effects of maintenance nortriptyline and placebo on electroencephalographic sleep measures in elderly recurrent depressives who survived 1-year without recurrence of depression. Patients on nortriptyline took longer to fall asleep and did not maintain sleep better than patients on placebo; however, maintenance nortriptyline was associated with more delta-wave production and higher delta-wave density in the first non-REM (NREM) period relative to the second. Nortriptyline levels were positively but weakly related to all-night delta-wave production during maintenance (accounting for 6.6% of the variance in delta-wave counts). Total phasic REM activity increased 100% under chronic nortriptyline relative to placebo, with a robust increase in the rate of REM activity generation across the night. Effective long-term pharmacotherapy of recurrent major depression is associated with enhancement in the rate of delta-wave production in the first NREM period (i.e., delta sleep ratio) and of REM activity throughout the night.

Differences over the life span in daily life-style regularity.

A diary-based instrument-the Social Rhythm Metric (SRM)-was used to assess the level of stability of daily social and behavioral rhythms in a group of 239 healthy subjects (112 male, 127 female) ranging in age from 20 to 89 years. Each subject completed the instrument for two consecutive weeks, which were averaged to yield one measure (SRM score) of life-style regularity [range 0 (least regular) to 7 (most regular)] and another of activity level index (ALI), corresponding to the number of (diary listed) activities done per week (max. = 119). SRM score increased reliably with age group at an average rate of 0.018 units per year. ALI showed an "inverted U"-shaped function with a maximum at about 50 years. SRM changes appeared not to be related to demographic differences between the age groups, although ALI differences may have been so related. No main effects or interactions were found with gender. Life-style regularity appears to increase over the life span in response to both biological and psychosocial changes and may represent an adaptation to age-related changes in the circadian system's sensitivity to entraining agents. Regular behavioral rhythms may be conducive to continued good health and well-being.

Sleep in the wake of complicated grief symptoms: an exploratory study.

Our aim was to explore the concept that the symptoms of complicated grief may be a form of posttraumatic distress, rather than depression, and thus may have different effects on sleep. Sixty-five recently bereaved elders with varying levels of symptoms of complicated grief and depression were stratified by high versus low levels of symptoms; a two-way analysis of variance examined main effects of level of complicated grief symptoms and depressive symptoms on selected sleep measures, as well as interactions. Complicated grief symptoms were independently associated with mild subjective sleep impairment but showed no main effects on electroencephalographic (EEG) sleep measures. In a multiple regression analysis, complicated grief symptoms interacted with depressive symptoms to increase REM sleep percent. Thus, it appears that complicated grief symptoms do not entail the changes of EEG sleep physiology seen in depression, with the possible exception of an interaction with coexisting depression to enhance REM sleep percent.

Longitudinal changes in diary- and laboratory-based sleep measures in healthy "old old" and "young old" subjects: a three-year follow-up.

We report a longitudinal study of diary- and laboratory-based sleep measures in 50 healthy elderly subjects followed prospectively over a 3-year interval. Our hypothesis was that "old old" subjects (aged 75 to 87; n = 27) would show decline over time in measures of sleep quality, continuity, and depth, whereas "young old" subjects (aged 61 to 74; n = 23) were expected to show stability of outcome measures. Using analysis of variance-based planned contrast procedures, we found that this hypothesis was strongly supported for subjective sleep quality and laboratory measures of sleep latency, sleep efficiency, wakefulness after sleep onset, and slow-wave sleep percent. These changes were accompanied by increased napping in the old old. However, there was no change of habitual time in bed (total time or temporal placement of nighttime sleep), daily social rhythms, or sleep apnea. Change in medical burden scores did not correlate significantly with change in sleep efficiency or other outcome variables in the old old. Intervention designed to slow age-dependent decreases in sleep quality, continuity, and depth is discussed. The current results are representative of healthy elderly; sleep would probably deteriorate earlier and more quickly in elderly with more serious health problems and heavier medication use.

Social rhythm stability following late-life spousal bereavement: associations with depression and sleep impairment.

The aim of this study was to investigate changes in social rhythm stability and sleep in spousally bereaved subjects (n = 94) and in nonbereaved elderly control subjects (n = 45). Social rhythm stability and activity level were measured with a diary-like instrument, the Social Rhythm Metric (SRM). We observed that spousal bereavement, per se, was not associated with a lower social rhythm stability or activity level except in the presence of a major depressive episode. We also observed an inverse correlation between severity of depression and social rhythm stability, and a positive correlation between depression and both subjective and objective measures of sleep impairment. Higher social rhythm stability was correlated with better sleep in subjects with high activity levels, but not in subjects with low activity levels. Longitudinal data, including pre-bereavement assessment of social rhythm stability, are necessary to ascertain directional effects, i.e., whether loss of spouse occasions disruption of social rhythms or whether such disruption precedes sleep impairment and depression.

Longitudinal effects of nortriptyline on EEG sleep and the likelihood of recurrence in elderly depressed patients.

Our objectives were to determine the effects of nortriptyline and placebo on subjective and EEG sleep measures over 1 year of maintenance therapy in elderly depressed patients and to determine the relationship of such effects to recurrence in nortriptyline or placebo-treated patients during maintenance therapy. EEG and subjective sleep assessments were conducted before and during a maintenance therapy study of patients suffering from major depression. During acute treatment all patients received nortriptyline plus interpersonal psychotherapy (IPT). During maintenance treatment patients were randomly assigned to double-blind treatment in one of four cells: nortriptyline with IPT; nortriptyline with medication clinic (no IPT); placebo with IPT; or placebo with medication clinic. Sleep evaluations were conducted at one point before treatment, one point following remission during continuation nortriptyline/IPT treatment, and at three time points after random assignment to maintenance treatment. The setting was the sleep laboratory of the outpatient depression treatment clinic, and subjects were a convenience sample of media-recruited and clinically referred elderly outpatient depressed patients (n = 72). Complete sleep analyses were conducted for 21 nortriptyline- and 10 placebo-treated patients throughout 1 year of maintenance treatment. The main outcome measures were subjective and EEG sleep measures and the recurrence of major depression. Our results show that nortriptyline acutely and persistently decreased REM sleep, increased phasic REM activity, decreased sleep apnea, and had no effect on periodic limb movements during sleep. Recurrence on maintenance nortriptyline was associated with lower phasic REM activity during early continuation therapy, but EEG sleep measures did not predict recurrence during placebo maintenance therapy. Patients treated with nortriptyline had a lower recurrence rate than those treated with placebo. Better subjective sleep quality and maintenance IPT were associated with a lower rate of recurrence regardless of nortriptyline treatment. It seems that nortriptyline has persistent effects on REM sleep and sleep apnea in elderly depressed patients. Maintenance nortriptyline, maintenance IPT, good subjective sleep quality, and high-phasic REM activity are associated with a reduced likelihood of the recurrence of depression during maintenance therapy.

Electroencephalographic sleep profiles during depression. Effects of episode duration and other clinical and psychosocial factors in older adults.

BACKGROUND: Limited evidence suggests that polysomnographic alterations may be more prominent early in a depressive episode. Whether the effects of episode duration extend beyond middle age and appear in late-life depression as well has important implications for treatment decisions and for understanding depressive illness across the life span. Furthermore, the impact of episode duration on sleep has not been examined in the context of other factors related to clinical history and psychosocial status. METHODS: Eighty-three persons aged 60 years or older with recurrent depression were studied: 34 had been depressed for 2 to 16 weeks and 49 for longer periods. An age- and gender-matched group of 48 persons with no history of major depression served as controls. Initial univariate analyses examined duration effects on electroencephalographic (EEG) sleep measurements. Multivariate analyses considered the combined effects of episode duration, clinical variables, and psychosocial variables on EEG sleep profile. RESULTS: Episode duration was strongly associated with sleep continuity, architecture, and rapid eye movement: subjects who were earlier in their depressive episodes had their sleep impaired more than those later in their episodes, who, in turn, were more impaired than controls. Moreover, clinical characteristics of subjects' depressive illness, demographic variables, and psychosocial stressors and supports had unique effects on the EEG sleep profile. CONCLUSION: Episode duration appears to be a potent factor to consider when evaluating sleep during depression. The additional contribution of clinical and psychosocial characteristics to the prediction of the EEG sleep profile demonstrates the importance of incorporating these variables into models of the psychobiologic characteristics of depression. The results are relevant to the timing and focus of therapeutic interventions.

A longitudinal study of laboratory- and diary-based sleep measures in healthy "old old" and "young old" volunteers.

The major aim of this study was to examine laboratory- and diary-based measures of sleep in a group of healthy ("successfully aging") "old old" subjects (> or = 75 years of age), as contrasted with a group of "young old" subjects (60-74 years of age), who were followed longitudinally for 2 years. We hypothesized that sleep would deteriorate to a greater extent over time among the old old subjects than among the young old. The study group consisted of 50 elders (21 male, 29 female; 23 old old, 27 young old), each studied at baseline and then again at 1- and 2-year follow-up. Analysis of variance was used to determine main effects of age group, gender and time on key sleep measures. Most measures were found to be remarkably stable over time. However, some decay was detected in sleep efficiency among the old old, but not among the young old. In a multiple regression model for the cohort as a whole, age, cognitive status and medical burden at baseline predicted subsequent declines in sleep efficiency over the 2-year period. To our knowledge, this is the first longitudinal data set on sleep in the healthy old old.

Sleep in bereavement-related depression during and after pharmacotherapy with nortriptyline.

Our objective was to assess the effects of nortriptyline on electroencephalographic sleep and subjective sleep quality in spousally bereaved, depressed elders. Ten elderly volunteers with bereavement-related major depression had electroencephalographic sleep studies while depressed, after remission of depressive symptoms while still taking nortriptyline, and after nortriptyline discontinuation. Changes in sleep measures over time were compared both within bereaved subjects and with age- and sex-matched healthy controls. Remission of depressive symptoms while still on nortriptyline was associated with improvements in sleep quality (P < .002), rapid eye movement (REM) percent (P < .02), REM latency (P < .05), REM density (P < .05), and delta sleep ratio (P < .05). After discontinuation of nortriptyline, REM percent, REM latency, and delta ratio reverted to pretreatment levels, while sleep efficiency and sleep quality continued to show improvement coincident with sustained clinical remission. These data suggest that nortriptyline may be clinically useful in treating the sleep disturbance of elders with bereavement-related depression and that a double-blind, placebo-controlled, randomized clinical trial is warranted.

Psychosocial correlates and sequelae of electroencephalographic sleep in healthy elders.

This research examines longitudinal data on psychosocial status and polysomnographic sleep collected annually from 57 healthy, community-residing elders aged 61-89. Cluster analysis of variables reflecting sleep continuity and architecture at the baseline assessment was used to identify three groups of elders: those whose sleep was either (a) superior to all remaining respondents across a variety of measures, (b) marred only by significantly reduced sleep efficiency relative to other respondents, or (c) poorer than all other respondents in multiple areas. Cross-validation procedures suggested that the three-group cluster solution was stable and replicable over persons and over time. Subsequent multivariate analyses indicated that recent life events, as well as psychosocial stability and support variables at baseline, distinguished between the sleep pattern groups. Moreover, sleep pattern group membership itself predicted subjects' subsequent sleep characteristics and psychosocial status at follow-up. Implications of these results for conceptualizing psychosocial factors that affect, and are ultimately affected by, sleep disturbances in late life are discussed.

Sleep after spousal bereavement: a study of recovery from stress.

AIM: In this study, we compared repeated measures of electroencephalographic (EEG) sleep and subjective sleep quality in nondepressed, spousally bereaved elders and a healthy control group, in order to search for possible psychobiological correlates of bereavement not confounded by concurrent major depression. METHOD: Laboratory-based EEG sleep studies and measures of subjective sleep quality (Pittsburgh Sleep Quality Index [PSQI]) were repeated at 3, 6, 11, 18, and 23 months after spousal bereavement in a study group of 27 elderly volunteers. Data were compared with similar measures from a control group of 27 nonbereaved subjects recorded on three occasions 1 year apart. Repeated-measures analysis of variance (ANOVA), using age as a covariate, examined effects due to time on selected variables in the bereaved group, as well as effects due to group, time, and group-by-time interactions in the experimental and control subjects. RESULTS: Bereaved and control groups showed consistent differences over time in the phasic measures of rapid eye movement (REM) sleep (higher in bereaved subjects during the first and third REM sleep periods), but were similar on all other EEG sleep measures over the 2 years of observation. The bereaved showed a small decline in the percentage of slow-wave sleep over 2 years, but measures of sleep efficiency, REM latency, and delta sleep ratio were stable and did not differ from values seen in control subjects. Bereaved and control subjects were also similar on subjective sleep quality. CONCLUSION: During successful adaptation to the loss of a spouse, and in the absence of major depression, spousal bereavement is associated with elevation in the phasic measures of REM sleep but does not appear to be associated with other physiologic sleep changes typical of major depression when studied at 3 to 23 months after the event. Although this observation does not preclude the possibility of significant sleep disturbance nearer the time of the event, it suggests that preservation of normal sleep following a major negative life event may be an important correlate of the resilience seen in successful aging. The elevation in REM density may provide a psychobiological correlate of bereavement not confounded by concurrent major depression.

Peripheral thermal responsivity to facial cooling during sleep.

A recently developed technique for examining thermal sensitivity during sleep was used to assess whether skin and core temperature responses to thermal stimulation were altered by sleep state. The technique was designed to probe thermal responsivity without altering core body temperature or inducing awakening. Twenty-seven young men and women were studied during a sleep deprivation night and a sleep night three nights later. Cold water stimulation of the face alternated with an equal period of rewarming across a 40-min cycle throughout the night. Skin temperature from the finger and rectal temperature were continuously assessed. Sleep continuity and architecture were largely uninfluenced by the thermal stimulation. Finger skin temperature decreased during cold facial stimulation in both sleep and waking states. Skin temperature changes during sleep were approximately one-fifth the magnitude of those during waking. Core temperature was minimally influenced. REM sleep was associated with a greater amplitude decrease in finger temperature than was non-REM (NREM) sleep. The results support the utility of the technique as a probe of thermal responsivity during sleep and suggest a reduction of thermal responsivity during sleep and, more tentatively, an altered responsivity during REM versus NREM sleep.

Age and sleep modify finger temperature responses to facial cooling.

BACKGROUND: The increased incidence of hypothermia with age suggests that healthy 80-year-olds might show impaired responsivity to transient, localized thermal stimulation. Such a deficit might be particularly clear during sleep, when behavioral thermoregulation is less likely. METHODS: We examined finger temperature cooling in response to local cooling of the face--a response presumed to be centrally mediated. Nineteen healthy 80-year-olds (12 female) and twenty-seven 20-year-olds (10 female) were exposed to repetitive 20-minute cooling and rewarming cycles across a night of sleep deprivation and a night of sleep occurring three nights later. We sought to determine whether thermal responsivity was altered by age and sleep, but by design avoided inducing core temperature hypothermia. RESULTS: In response to facial cooling during sleep deprivation, finger temperature decreased significantly more in the young than in old. This suggested relatively greater heat retention in the young. During non-REM sleep the thermal responsivity of both groups decreased and age-related differences were no longer present. Changes in core temperature induced by the stimulation were minimal. CONCLUSIONS: The results suggest that the capability of retaining heat via peripheral vasoconstriction while awake decreases with age. Despite this vulnerability, responsivity during non-REM sleep as well as average core temperature were comparable between age groups.

Electroencephalographic sleep in recently remitted, elderly depressed patients in double-blind placebo-maintenance therapy.

The aim of this double-blind placebo-controlled study was to assess the effects of clinical state on electroencephalographic (EEG) sleep measures in elderly patients with recurrent major depression. We hypothesized that rapid-eye movement (REM) latency and delta sleep ratio would remain stable between actively depressed and remitted states (i.e., show state independence), and measures of sleep continuity would improve with remission (i.e., show state dependence). Fifteen elderly outpatients (mean age 65.3 years) had sleep evaluations while ill and after remission, an average of 38 weeks later. All patients were in a double-blind placebo-maintenance condition at the time of follow-up studies. The major findings were: 1) no significant change in either REM latency or delta sleep ratio; 2) reduction in early morning awakening; and 3) improvement in subjective sleep quality despite the stability of most polysomnographic measures. We conclude that REM latency and delta sleep ratio are state-independent in patients with late-life depression, and that early morning awakening and sleep quality improve with remission of symptoms. These findings suggest that EEG sleep changes may have significance for understanding the longitudinal course of depression in late life.

Sleep-disordered breathing in healthy and spousally bereaved elderly: a one-year follow-up study.

This study examined the progression of sleep-disordered breathing (SDB) over 1 year in two samples of elderly subjects: 45 healthy controls (20 men; 25 women mean age 74.8 years) and 27 recently spousally bereaved elders (9 men; 18 women, mean age 69.7 years). Although controls and bereaved subjects did not differ in the proportions with SDB, both groups showed a rise in the proportion of subjects with apnea hypopnea index > or = 5 and > or = 10 at 1-year follow-up and a small but statistically significant worsening in average maximum desaturation. The severity of SDB did not correlate with medical burden or with other clinical variables, such as severity of depressive symptoms. In summary, SDB increased longitudinally in both samples. This finding may have health implications for the aging population although at this time the implications are unclear.

Sleep in spousally bereaved elders with subsyndromal depressive symptoms.

Spousal bereavement in late life frequently leads to major depression. However, many people suffer from "minor" depressive symptoms that entail considerable suffering even in the absence of syndromal major depression. We describe longitudinal electroencephalographic (EEG) sleep and clinical evaluations in 14 elderly, recently spousally bereaved subjects who were experiencing subsyndromal depressive symptoms. While subjects did not meet diagnostic criteria for syndromal major depression, they did have mildly elevated scores on the Hamilton Rating Scale for Depression (mean = 10.6, range = 8-16) at the time of initial sleep studies (T1), which were carried out, on average, 5.5 months after loss of the spouse. Entry into the study was limited to volunteers who did not have a personal history of major depression or psychiatric disorder. Twelve subjects underwent followup clinical and EEG sleep evaluations (T2), 9.9 months after spousal loss. Fifty percent continued to show depressive symptoms at 6-month followup. Test-retest comparisons of sleep and clinical measures were made with a group of sex- and age-matched control subjects who were neither bereaved nor depressed. EEG sleep measures did not significantly correlate with time from loss of spouse, severity of depressive symptoms, or subjective sleep quality. Analysis of variance with repeated measures detected a significant group X time interaction effect for delta sleep ratio (decreasing in controls but increasing in the bereaved).

Daytime sleepiness and performance among healthy 80 and 20 year olds.

This study investigated the relationship of daytime sleepiness and performance on a vigilance test in a sample of 10 healthy men and 13 women in their 80s (mean age 83.0 +/- 3.1 years) and 18 men and 12 women in their 20s (25.0 +/- 3.1). We hypothesized that "successfully" aged healthy individuals would have more daytime sleepiness with differentially greater decrements in performance than a younger comparison group. Daytime sleepiness was measured physiologically by the Multiple Sleep Latency Test (MSLT) and through self-report by the Stanford Sleepiness Scale (SSS). Morning and evening performance was measured with the Mackworth Clock Test of vigilance. The major findings were the absence of correlation between either MSLT or SSS daytime sleepiness with performance measures, no difference in daytime sleepiness between the old and young groups and performance decrements among the healthy elderly on all parameters. Results suggest that the modest decrements in performance among the elderly cannot be attributed to daytime sleepiness.

Rapid eye movement sleep deprivation in elderly patients with concurrent symptoms of depression and dementia.

Rapid eye movement (REM) sleep measures distinguish elderly patients with depression from those with dementia. The authors used a 2-night REM sleep deprivation (RSD) protocol to characterize patients with mixed symptoms of depression and dementia in comparison with patients with "pure" depression or dementia and healthy controls. Mixed-symptom patients resembled dementia patients in baseline sleep measures, but their large change in phasic REM activity following RSD suggests neurobiological similarities to depression. Mixed-symptom patients with stable cognitive impairment had greater REM sleep rebound than those with a more progressive dementing course. These results are consistent with previous neuropathological and neurochemical data.

Electroencephalographic sleep in spousal bereavement and bereavement-related depression of late life.

Although spousal bereavement in late life is common and frequently leads to major depression, the boundary between bereavement without a depressive syndrome and bereavement-related depression has been insufficiently studied from a physiological perspective. Because other forms of depression are associated with physiological changes, including sleep, we have attempted to clarify the relationship of bereavement and bereavement-related depression by investigating electroencephalographic (EEG) sleep in 31 elderly volunteers with recent spousal bereavement, stratified by the presence (n = 15) or the absence (n = 16) of major depression (Research Diagnostic Criteria). Entry into the study was limited to volunteers without a personal history of psychiatric disorder. As hypothesized, bereaved subjects with major depression had significantly lower sleep efficiency, more early morning awakening, shorter rapid eye movement (REM) latency, greater REM sleep percent, and lower rates of delta wave generation in the first nonREM (NREM) period, compared with bereaved subjects without depression. Furthermore, the sleep of bereaved subjects with single-episode major depression resembled that of elderly patients with recurrent unipolar major depression (n = 15) on measures noted above. Sleep in bereavement without depression was similar to that of 15 healthy control subjects (neither bereaved nor depressed). These findings suggest that the current DSM-III-R concept of uncomplicated bereavement is not confirmed, as the sleep patterns of subjects who develop a depressive syndrome in the context of bereavement, many of whom might be considered to have "uncomplicated bereavement" by DSM-III-R standards, are identical to sleep patterns found in major depressive episodes. To our knowledge, this is the first study of EEG sleep in spousal bereavement with and without major depression.