Habitual sleep patterns and risk for stroke and coronary heart disease: a 10-year follow-up from NHANES I

BACKGROUND

Habitual sleep patterns may independently affect morbidity and mortality. However, the effect of habitual sleep patterns on the risk for stroke and coronary heart disease is unclear.

METHODS

We evaluated the association between sleep duration and daytime somnolence (often or almost always taking daytime naps) with the incidence of stroke and coronary heart disease in a national cohort of 7,844 adults who participated in the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. Cox proportional hazards analyses were used to examine these relationships during the 10-year follow-up.

RESULTS

After adjusting for differences in age, race, gender, education, cigarette smoking, body mass index, serum cholesterol, systolic blood pressure, and diabetes mellitus, the risk for stroke was increased in persons who reported sleeping greater than 8 hours at night compared with persons who slept between 6 and 8 hours (relative risk [RR] = 1.5, 95% confidence interval [CI] = 1.1 to 2.0). Daytime somnolence was also associated with stroke incidence (RR = 1.4, 95% CI = 1.1 to 1.8). Persons who reported both greater than 8 hours of sleep and daytime somnolence were at the greatest risk for stroke (RR = 1.9, 95% CI = 1.2 to 3.1). Similar results were also found for coronary heart disease, although the results did not reach statistical significance in the multivariate adjusted model.

CONCLUSIONS

Habitual sleep patterns have significant effects on the risk for stroke.

Sleep problems as a risk factor for falls in a sample of community-dwelling adults aged 64-99 years

OBJECTIVES

The purpose of this study was to determine if reported nighttime sleep problems and daytime sleepiness were associated with reported falling during the previous 12 months in a representatively sampled older adult population.

DESIGN

Random-digit dial telephone survey.

SETTING

Representatively sampled older adult population living in northern California.

PARTICIPANTS

Participants were 971 women and 555 men, aged 64 to 99 years.

MEASUREMENTS

Twenty-minute telephone interview adapted from the National Health Interview Survey.

RESULTS

Two hundred and eighty-four participants reported falling during the previous 12 months (19% of the sample). Significantly more women fell than men (20% and 14%, respectively, P < .001). The following variables were significant risk factors for falling in univariate analyses: female gender, being unmarried, living alone, income less than $15,000 per year, difficulty walking, having more than one chronic medical condition, history of cardiovascular disease, hypertension, arthritis, sensory impairment, psychological difficulties, and nighttime sleep problems. All of the nighttime sleep problem variables remained significant risk factors for falling after controlling for other risk factors for falling.

CONCLUSIONS

The results provide support for an independent association between reported sleep problems and falls in an older population. One of the implications of these data is that behavioral research focusing on the effectiveness of insomnia treatment in old age should not only examine typical sleep-related outcomes (e.g., total time asleep, number of awakenings) but also the occurrence of falls as well.

FAST TRACK: daytime sleepiness in Parkinson's disease

We describe multiple sleep latency test (MSLT) results in 27 adult patients with idiopathic Parkinson's disease (PD). Pathological sleepiness (i.e. mean sleep latency </=5 min) was common (40 of 134 nap opportunities), and sleep-onset REM periods were also observed (13 of 134 nap opportunities). These findings bore little relationship to disease specific variables (e.g. level of disability, medication use), or sleep architecture measures (e.g. total sleep time, sleep stage percentage's). Our findings speak against a simple association of excessive sleepiness and the quality and quantity of prior night's sleep, but rather, argue for primary impairments of waking arousal and REM-sleep expression in a sizeable subpopulation of PD patients.

Predictors of early deterioration and mortality in black Americans with spontaneous intracerebral hemorrhage

BACKGROUND AND PURPOSE

Black Americans with spontaneous intracerebral hemorrhage (SICH) may have unique clinical characteristics that affect outcome. The aim of this study was to determine the prognostic value of clinical characteristics and initial CT scan for outcome in black Americans with SICH.

METHODS

Clinical and demographic data were extracted from the charts of 182 consecutive black Americans admitted for SICH diagnosed by clinical criteria and initial CT scan. Hemorrhage volumes were calculated from admission CT scans by a computerized method. Univariate and multiple logistic regression analyses were performed to determine independent predictors of early deterioration (defined as a decrease from an initial Glasgow Coma Scale score > 12 by > or = 4 points within 24 hours from presentation) and mortality.

RESULTS

Both hemorrhage volume and ventricular extension were significant, independent predictors of early deterioration (odds ratio [OR], 6.78; 95% confidence interval [CI], 1.89 to 24.35 and OR, 4.67; 95% CI, 1.30 to 16.72, respectively) and mortality (OR, 6.66; 95% CI, 2.85 to 15.58 and OR, 4.23; 95% CI, 1.82 to 9.82, respectively). A Glasgow Coma Scale score < or = 12 also predicted mortality (OR, 3.23; 95% CI, 1.46 to 7.14). Initial mean arterial pressure was not an independent predictor of early deterioration or mortality.

CONCLUSIONS

Hemorrhage volume and ventricular extension are the best predictors of early deterioration and mortality in black Americans with SICH.

Sleep apnea and mortality in an aged cohort

In the aged, sleep may be a vulnerable period for death from cardiovascular causes. Because of its high prevalence in the elderly, sleep apnea has been suggested to be one mechanism contributing to such sleep-related mortality. In this study, a cohort of 198 non-institutionalized elderly individuals (mean age at entry = 66) were followed for periods up to 12 years after initial polysomnography. The mortality ratio for sleep apnea (defined as a Respiratory Disturbance Index of over 10 events per sleep hour) was estimated to be 2.7 (95% CI = .95, 7.47). Multiple regression with the Cox proportional hazards model suggested that cardiovascular death was most clearly associated with age in this cohort. These results raise the possibility that "natural" death during sleep in the elderly may be associated with specific pathophysiological events during sleep.

Rate of 24-hour blood pressure decline and mortality after spontaneous intracerebral hemorrhage: a retrospective analysis with a random effects regression model

OBJECTIVE

To study the effect of decline in blood pressure on mortality in patients with spontaneous intracerebral hemorrhage (ICH).

DESIGN

Retrospective chart review.

SETTING

University-affiliated teaching hospital.

PATIENTS

Consecutive patients admitted with spontaneous ICH over a 3-year period.

MEASURES

Blood pressure recordings were obtained from the first 24 hrs. Patients (n = 105) with more than five blood pressure recordings and on average greater than one measurement per 2 hrs were included (mean measurements per patient = 20.3). Mean arterial pressure (MAP) recordings over the first 24 hrs after presentation were regressed on time for each patient. Each patient's MAP was calculated as a slope (change mm Hg/hr). We performed logistic regression analyses to determine the effect of MAP slope on mortality and functional outcome, adjusting for other predictive factors including Glasgow Coma Scale (GCS) score and hematoma volume. The effect of MAP slope on mortality was also evaluated in subsets of patients based on age, gender, initial GCS score, initial MAP, treatment status, hematoma volume, and presence of ventricular blood.

MAIN RESULTS

Mean slope of change in MAP was -2.0 mm Hg/hr (+/- 1.9, range -8.5 to +0.6). The slope of MAP (faster rate of decline) within the first 24 hrs was significantly associated with higher mortality (p =.04), independent of initial GCS score and hematoma volume. In subgroup analyses, MAP slope was significantly associated with mortality in men (p = .08), patients with hematoma volume <50 mm3 (p =.08), initial MAP < or = 146 mm Hg (p = .006), and those with initial GCS score > or = 10 (p= .07). MAP slope did not predict functional outcome among survivors.

CONCLUSIONS

A rapid decline in MAP within 24 hrs after presentation is independently associated with increased mortality in patients with ICH. A large, prospective, randomized trial is required to confirm these findings.

Relative validity of self-reported snoring as a symptom of sleep apnea in a sleep clinic population

The purpose of this study was to evaluate the relative validity of responses to three different questions about snoring as indicators for sleep apnea in a population referred to a sleep clinic. Secondary goals were to evaluate the meaning of a "don't know" response to these questions and to examine how the associations between snoring and sleep apnea are influenced by demographics. Results from 1,409 patients in a sleep clinic indicated that nearly all levels of estimated snoring frequency were associated with a greater likelihood of sleep apnea. In addition, a "don't know" response indicated a likelihood of sleep apnea. In the sample from this clinic, sensitivities approximating 90 percent were obtained in men, and specificities approximating 90 percent were obtained in women, but high diagnostic accuracy (high specificity in men; high sensitivity in women) could not be achieved with the three snoring questions used here. Generally, associations between snoring and sleep apnea were independent of age and sex. Single persons, persons living alone, and persons customarily sleeping alone of both sexes all showed associations between self-reported snoring and the presence of sleep apnea.

Prevalence of self-reported poor sleep in a healthy population aged 50-65

Many population-based surveys have reported that the prevalence of poor sleep increases with age. Despite the uniformity of findings, it remains unclear to what extent age-related declines in overall physical health are related to those results. One approach to this problem has been to adjust for such confounding variables multivariately. Some prior studies using this approach have not shown the expected age-related increases in the prevalence of poor sleep. Another approach has been the study of sleep in carefully screened, healthy populations. The current study reports the prevalence of disturbed sleep in a population, ages 50-65, carefully screened for physical health as part of an ongoing study of exercise and cardiovascular function. The prevalence of self-reported trouble falling asleep every night or almost every night (1.1% M, 2.6% F), trouble awakening and returning back to sleep (4.4% M, 3.3% F), and use of hypnotic medication at least twice a week (1.6% M, 2.6% F) were consistently lower than in nearly all previous population-based studies of individuals of comparable age. This implies that when overall physical health factors are taken into account a decline in sleep quality is not necessarily an inevitable component of aging per se. As has been shown in other studies, there were small but statistically significant relationships between self-reported depression and poor sleep. Despite the low prevalence of poor sleep, about a third of the population reported feeling not well-rested and/or not getting the sleep they required. The individuals in this study also reported obtaining significantly less sleep relative to normative data from 30 years ago.(ABSTRACT TRUNCATED AT 250 WORDS)

Laboratory sleep correlates of nightmare complaint in PTSD inpatients

BACKGROUND

Nightmares are rare in the sleep laboratory, even in patients with posttraumatic stress disorder for whom nightmare complaints are diagnostic. Nevertheless, it is possible that laboratory conditions do not preclude the observation of telltales-nightmare-related modifications of tonic sleep-given sufficiently large samples.

METHODS

Sixty-three unmedicated, nonapneic Vietnam combat veterans undergoing inpatient treatment for posttraumatic stress disorder underwent polysomnographic testing and assessment of nightmare complaint.

RESULTS

Trauma-related nightmare complaint, but not non-trauma-related complaint, was associated with increased wake-after-sleep-onset in the sleep laboratory. No relationships between nightmare complaint and rapid eye movement sleep architecture were observed.

CONCLUSIONS

Increased wake-after-sleep-onset was specifically associated with trauma-related nightmare complaint, confirming data from other quarters suggesting they are both phenomenologically and functionally distinct from normal dreaming.

An actigraphic comparison of sleep restriction and sleep hygiene treatments for insomnia in older adults

We compared the efficacy of sleep restriction therapy combined with sleep hygiene, nap modification of sleep restriction therapy combined with sleep hygiene, and sleep hygiene alone as treatments for insomnia in 39 community-dwelling men and women 55 years and older. We used the wrist actigraph as an objective outcome measure for all subjects at baseline, end of treatment, and 3-month follow-up; polysomnography (PSG) was conducted in a subgroup of subjects. Although subjects appeared to follow restriction instructions through follow-up, we found few between-group differences in treatment efficacy. Lack of treatment effect might be explained by the efficacy of HYG as a treatment in itself and the relatively low symptom level in these healthy older poor sleepers. At baseline, actigraphic results were found to correlate more highly than sleep log data with PSG in our sample. Actigraphic total sleep time, in particular, was highly correlated with PSG.

The relations among caregiver stress, "sundowning" symptoms, and cognitive decline in Alzheimer's disease

OBJECTIVE

To investigate the relations among the initial perceived stress of Alzheimer patients' caregivers, the rate of change of perceived stress, patients' sundowning behaviors, and patients' rate of cognitive decline.

DESIGN

A longitudinal cohort study in which Alzheimer patients and their caregivers were assessed at 6-month intervals.

SETTING

Hospital out-patient clinic. Patients and caregivers lived at home.

SUBJECTS

Subjects were 35 patients (50-79 years) with Alzheimer's disease and their primary caregivers (24 males and 11 females); all caregivers were spouses.

METHODS

At time of entry into the study, caregivers indicated which of seven behaviors indicative of sundowning were exhibited by the patient. Patients were evaluated successively using the Mini-Mental State Examination, whereas caregivers completed the Perceived Stress Scale, provided an index of social support utilization, and completed the Beck Depression Inventory.

MAIN OUTCOME MEASURES

Caregivers' initial perceived stress and the rate of change of perceived stress, patients' sundowning behavior, and rate of cognitive decline.

RESULTS

The pattern of correlations indicated that both rate of cognitive decline and initial sundowning behavior were significantly correlated with initial perceived caregiver stress. The average rate of increase of caregivers' perceived stress was positively correlated with the initial incidence of sundowning behaviors, even when controlling for the effects of caregiver depression and social support utilization.

CONCLUSION

Sundowning behavior of Alzheimer patients is associated with an increased rate of change of caregivers' perceived stress. This association may be specific to sundowning behavior because there was no relation between the rate of change of perceived stress and morning agitation. The findings suggest that future caregiver intervention programs could profitably focus on sundowning behavior rather than general agitation.

Prevalence of sleep apnea and electrocardiographic disturbances in morbidly obese patients

OBJECTIVE

To determine the prevalence of sleep apnea in morbidly obese patients and its relationship with cardiac arrhythmias.

RESEARCH METHODS AND PROCEDURES

Fifty-two consecutive morbidly obese (body mass index > or = 40 kg/m2) outpatients from the Obesity Clinic of the National Institute of Nutrition Salvador Zubirán underwent two nights of polysomnography with standard laboratory techniques. Electrocardiographic polysomnography signals (Lead II) were evaluated by two experienced cardiologists, and sleep complaints were measured with a standard sleep questionnaire (Sleep Disorders Questionnaire). In order to make comparisons between groups with different severities of sleep-disordered breathing, we classified the patients in four groups using the apnea-hypopnea index (AHI): Group 1, AHI 5 < 15 (n = 10); Group 2, AHI 15 < 30 (n = 10); Group 3, AHI 30 < 65 (n = 14); Group 4, AHI > or = 65 (n = 17).

RESULTS

A wide range of sleep-disordered breathing, ranging from AHI of 2.5 to 128.9 was found. Ninety-eight percent of the sample (n = 51) had an AHI > or = 5 (mean = 51 +/- 37), and 33% had severe sleep apnea with AHI > or = 65 with a mean nocturnal desaturation time of <65% over 135 minutes. Electrocardiographic abnormalities were present in 31% of the patients. Cardiac rhythm alterations showed an association with the level of sleep-disordered breathing and oxygen desaturation.

DISCUSSION

We conclude that there is a high prevalence of sleep apnea in morbidly obese patients and that the risk for cardiac arrhythmias increases in this population in the presence of a severe sleep apnea (AHI > or = 65) with severe oxygen desaturation (SaO2 < or = 65%).

Use of the wrist actigraph to study insomnia in older adults

Measures derived from the wrist actigraph have been found to correlate highly with EEG measures of normal sleep. Although the actigraph has been used to study normal sleep, few studies have used the actigraph as a measure of sleep of elderly insomniacs. The present study, which used elderly insomniacs, sought to investigate the sensitivity of the actigraph to detect the effects of an insomnia treatment. The actigraph was sufficiently sensitive to detect the effect of the sleep restriction therapy used on several sleep measures. Subsidiary analyses suggested that the sleep log, although not an accurate measure of sleep, may be useful as a measure of elderly insomniacs' subjective perception of sleep. Because the actigraph can be used more easily and less expensively than the polysomnogram, the actigraph appears to be a promising measure for assessing the efficacy of treatment interventions in elderly insomniacs.

PTSD-related hyperarousal assessed during sleep

Posttraumatic stress disorder is widely understood to include "persistent symptoms of increased arousal." This presumption has rarely been tested under conditions in which effects of anticipatory anxiety could be ruled out. In this study, heart rate and electroencephalogram spectral power were assessed during sleep, a state free of most sources of artifact contaminating indices of tonic arousal. Fifty-six unmedicated nonapneic Vietnam combat-related inpatients with posttraumatic stress disorder (PTSD) and 14 controls spent 3 or more nights in the sleep laboratory during which their electrocardiograms and electroencephalograms were continuously recorded. Heart rate and electroencephalogram spectral power were quantified continuously off-line and averaged by sleep stage over all postadaptational nights. Sleep heart rate exhibited no group differences and no covariation with the severity of subjective hyperarousal reported by PTSD patients. PTSD patients exhibited a trend toward reduced low-frequency electroencephalogram spectral power during nonrapid-eye-movement (NREM) sleep. This reduction was significant during slow-wave sleep in those subjects producing scoreable slow-wave sleep. The relationship of rapid-eye-movement (REM) beta-band power to NREM beta-band power was different in PTSD patients and controls, with the patients exhibiting more beta in REM versus NREM sleep than controls. In patients, NREM sleep sigma-band electroencephalogram spectral power exhibited a positive correlation with subjective hyperarousal. Finally, a novel and surprisingly strong inverse correlation between REM-NREM sleep heart rate difference and REM percent of sleep was observed in PTSD patients only. In summary, peripheral and central measures of tonic arousal during sleep demonstrated contrastive relations to PTSD diagnostic and symptom status. The data suggest that more consideration should be directed to mechanisms of central arousal in PTSD.

Sleep and "sundowning" in nursing home patients with dementia

"Sundowning," a term that is sometimes equated with sleep disturbance or nocturnal delirium in dementia, is a poorly understood psychiatric phenomenon. In this study, we performed systematic, temporally specific, behavioral observations of nine profoundly demented nursing home patients 4 times an hour over a 12-hour period (1300 to 0100h) to determine whether their agitation was more likely to occur at a particular time of day. Results indicated only equivocal evidence that agitation was any worse nocturnally or during the time near sunset, thus raising the possibility that at least some components of sundowning may reflect disruptive behaviors occurring with identical frequency throughout the day but with differential impact upon nursing staff. Additional data indicated that awakening from sleep during darkness was also associated with agitation. A final result was a trend indicating the apparent worsening of agitation seasonally (greater agitation during winter), which may suggest involvement of the circadian timing system.

A preliminary study comparing sleep restriction and relaxation treatments for insomnia in older adults

This study compared Sleep Restriction Therapy (SRT) and Relaxation Therapy (RLT) as treatments for insomnia in a sample of community-residing elderly (mean age, 69.7 years). SRT subjects (n = 10) and RLT subjects (n = 12) reported information about their sleep twice daily to a telephone recording machine for 2 weeks of baseline, 4 weeks of treatment, and 2 weeks at 3-month follow-up. Results showed sleep latency and waking after sleep onset were significantly reduced for both treatment groups under active treatment. Predictable reductions in time in bed and improved sleep efficiency reported during active treatment by SRT subjects were still apparent at 3-month follow-up; no corresponding changes were found for RLT. In both groups, increased total sleep time was reported at follow-up; the improvement for SRT subjects was approximately twice that seen in RLT. These findings, at this early stage in the development of behavioral treatments for insomnia in older adults, encourage further study.

Factors associated with nightly variability in sleep-disordered breathing in the elderly

The purpose of this study was to evaluate factors associated with nightly variability in sleep-disordered breathing. In this study, variability in sleep-disordered breathing over two consecutive laboratory nights was evaluated in 71 aged volunteers with varying levels of sleep apnea. High variability (n = 13) and low variability (n = 58) groups were formed on the basis of an absolute two-night apnea/hypopnea index difference of a minimum ten events per hour. Results indicate high variability was related to longer soft palate measurements and the presence of nasal obstruction on physical examination. Within the high variability group, variation in sleep-disordered breathing occurred within identical gross body position over the two nights. The results suggest that local, anatomic factors affecting airway patency may not be constant from night to night.

Cognitive function in patients with sleep apnea after acute nocturnal nasal continuous positive airway pressure (CPAP) treatment: sleepiness and hypoxemia effects

Patients with sleep apnea are typically hypersomnolent during the daytime and may demonstrate higher order cognitive dysfunction. A persistent problem in interpreting impaired neuropsychological test performance in such patients is whether the observed deficits can be explained wholly by impaired vigilance. We examined 37 sleep apnea patients prior to and immediately subsequent to successful sleep apnea treatment with nasal continuous positive airway pressure (CPAP). Patients were evaluated immediately after morning awakening in the sleep lab. A brief neuropsychological evaluation, was administered at that time. Following this, alertness was measured with a 30-min polysomnographically determined sleep latency test. Both test (approximately 50 min in duration) were performed once following a baseline (diagnostic) night in the sleep lab and once in the morning following a CPAP (therapeutic) night in the lab. Subgroup analyses indicted that while vigilance impairment can account for some of the decreased test performance seen in sleep apnea (auditory verbal learning) the effects of severe nocturnal hypoxemia appear to affect other function (sustained attention in repetitive arithmetic calculations) that were not easily modified by treatment. Thus, performance on the recall trial of the Rey Auditory Verbal Learning Test increased from pre-CPAP to post-CPAP for the increased alertness group but decreased significantly for the decreased alertness group. On the Wilkinson Addition Test, non-hypoxemic patients showed statistically significant improvement in problems correctly solved from pre-CPAP to post-CPAP, but the hypoxemic patients showed only a marginal increase. These results are compatible with other studies suggesting that patients having sleep apnea may incur deficits as a result of both decreased vigilance and hypoxemia, and that at least some of these deficits are immediately reversible.

Objective and subjective sleep disturbances in patients with systemic lupus erythematosus

OBJECTIVE

To assess objective and subjective evidence of sleep disorders in patients with systemic lupus erythematosus (SLE) and to examine correlations between parameters of lupus activity, depression, and sleep disturbances.

METHODS

Fourteen SLE patients and 11 normal control subjects of similar age underwent all-night polysomnography on 3 consecutive nights. The patients and controls were also evaluated for daytime sleepiness by the Multiple Sleep Latency Test and completed a sleep disorders questionnaire and the Beck Depression Inventory.

RESULTS

The polysomnographic data showed that sleep in SLE patients was characterized by respiratory and movement disorders. These intrinsic primary sleep disorders are related to the symptom of restless, poor sleep at night. Lupus patients were more sleepy during the day, and their sleepiness was related to sleep fragmentation, with more arousals and stage transitions than the control group. Disease activity was associated with decreases in sleep efficiency and delta sleep and with increases in sleep fragmentation. Depression was not correlated with the activity of the disease.

CONCLUSION

There is an enhanced presence of sleep disorders in patients with SLE. The most frequent primary sleep disorders are respiratory and movement disorders.

Observed sleep/wakefulness and severity of dementia in an Alzheimer's disease special care unit

BACKGROUND

This study tested the hypothesis that behaviorally defined sleep disturbance among residents in a Special Care Unit (SCU) for Alzheimer's disease (AD) was related to the severity of their dementia. Previously, sleep laboratory studies have reported such relationships when sleep has been recorded polysomnographically over several nights. Observational studies of sleep have not shown such relationships, presumably because of the impression involved in determining sleep/wake state behaviorally.

METHODS

Nightly sleep data based on observations made every two hours by nursing staff for a period of 13 to 18 months were examined for 47 AD residents with a mean age of 80.7 +/- 6.5 years. Level of dementia and functional capacity were assessed with the Mattis Dementia Rating Scale (DRS) and the Katz Activities of Daily Living Scale (ADL).

RESULTS

Data indicated that these SCU residents experienced a moderately disturbed night of sleep an average of 24% +/- 10% of their nights in the facility and a severely disturbed night of sleep on 7% +/- 6% of those nights. More profound dementia was associated with more sleep disturbance; however, incapacity in ADLs, age, gender, and psychoactive medications were unrelated to such disturbances.

CONCLUSIONS

The results indicate that patterns of relationships noted between laboratory-based measures of sleep and variables such as severity of dementia can be detected using behavioral observations of sleep, provided that the number of nights of observation are sufficiently large to offset the measurement error involved in their use.

Historical change in the report of daytime fatigue

Population-based data suggesting that contemporary society does not value sleep are difficult to obtain. In this report, historical change in item endorsements relevant for disturbed sleep and daytime fatigue from the Minnesota Multiphasic Personality Inventory (MMPI) generated from normative, upper Midwestern adult populations was analyzed. Response rates from the 1930s and 1980 were compared. The data indicated that, relative to individuals in the post-Great Depression/pre-World War II era, contemporary men were more likely to report fatigue and tiredness, although they were no more likely to report disturbed nocturnal sleep. The results are compatible with the voluntary curtailment of sleep typical in modern society described in the report of the National Commission on Sleep Disorders Research.

Preliminary communication: intellectual deficit and sleep-related respiratory disturbance in the elderly

Polysomnography and neuropsychological tests administered to 41 nondemented male subjects (mean age, 69.5) indicated that impaired performance was associated with sleep-related respiratory disturbance. Such deficits could reflect deficits in vigilance or cortical insult resulting from nightly hypoxemia. Whether the degree of impairment observed here predicts more severe dementia will await longitudinal studies.

REM latency in Alzheimer's disease

Latency to the first episode of rapid eye movement sleep (REML) has been proposed as a potential biomarker for Alzheimer's disease (AD). In this study, we compared REML values from 28 AD patients and 28 age- and sex-matched controls. We employed multiple definitions of REML and multiple cutoffs to classify patients and controls. Results indicated that the best REML definition and optimal cutoff criterion resulted in only 65% correct classifications. We discuss the longer REML in AD patients relative to controls in terms of both overall sleep disturbance and selective deterioration of the REM-cholinergic system. As REML may be relatively short in other forms of psychopathology (e.g., affective disorders), REML may still hold promise in the differential diagnosis of dementia and pseudodementia.

Randomized, double-blind, placebo-controlled, short-term trial of ropinirole in restless legs syndrome

BACKGROUND AND PURPOSE

Restless legs syndrome (RLS) is a condition characterized by an urge to move the legs, usually accompanied by lower limb paresthesias. These symptoms worsen at rest, are relieved by activity, and are worse at night. Previous studies have suggested that dopaminergic drugs such as L-dopa and dopamine agonists, as well as benzodiazepines and opioids, can treat RLS successfully. The purpose of this study was to test the clinical efficacy of ropinirole, a D2/D3 agonist, in the treatment of RLS in a double-blind, short-term, placebo-controlled clinical trial.

PATIENTS AND METHODS

After undergoing successful open-label titration and dose adjustments with ropinirole for RLS symptoms over a period of 4 weeks, 22 RLS patients (mean age=50.8; mean duration of symptoms=26.1 years) were randomized to receive either placebo (n=13) or ropinirole (n=9) for 2 additional weeks. Outcome measures included assessment of periodic leg movements in sleep (PLMS) recorded with nocturnal polysomnography and RLS symptoms as assessed with the International Restless Legs Syndrome Study Group (IRLSSG) Rating Scale. Secondary outcomes included sleep macroarchitecture.

RESULTS

Results indicated that relative to placebo, ropinirole, at a mean dose of 1.4mg HS significantly decreased PLMS and RLS symptoms. Sleep macroarchitecture did not change. Side effects were typical of all dopamine agonists and were dose related. The majority of patients elected to continue treatment with ropinirole upon study completion.

CONCLUSIONS

Ropinirole successfully treated long-standing RLS and can be considered a viable short-term treatment for this condition.