SLEEP

Crawford, B.

doi: 10.1093/sleep/20.10.829pmid: N/A

Summary:Sleep disorders have been shown to have substantial psychosocial sequelae with large economic impact. Numerous studies have examined the psychosocial aspects of sleep disorders; however, there has been little published on the associated economic implications. With increasing pressure to contain health care expenditures and provide value for the dollar, clinical economics is playing an important role in the decision-making process about alternative strategies within health care organizations. There are several strategies one may pursue to examine the economics of medical interventions. The predominant strategies include: cost identification, cost effectiveness, cost utility, and cost benefit. This review provides a basis for performing clinical economic evaluations in sleep disorders.

Weaver, Terri E.; Laizner, Andréa M.; Evans, Lois K.; Maislin, Greg; Chugh, Deepak K.; Lyon, Kerry; Smith, Philip L.; Schwartz, Alan R.; Redline, Susan; Pack, Allan I.; Dinges, David E

doi: 10.1093/sleep/20.10.835pmid: N/A

Summary:This article reports the development of the functional outcomes of sleep questionnaire (FOSQ). This is the first self-report measure designed to assess the impact of disorders of excessive sleepiness (DOES) on multiple activities of everyday living. Three samples were used in the development and psychometric analyses of the FOSQ: Sample 1 (n = 153) consisted of individuals seeking medical attention for a sleep problem and persons of similar age and gender having no sleep disorder; samples 2 (n = 24) and 3 (n = 51) were composed of patients from two medical centers diagnosed with obstructive sleep apnea (OSA). Factor analysis of the FOSQ yielded five factors: activity level, vigilance, intimacy and sexual relationships, general productivity, and social outcome. Internal reliability was excellent for both the subscales (α = 0.86 to α = 0.91) and the total scale (α = 0.95). Test-retest reliability of the FOSQ yielded coefficients ranging from r = 0.81 to r = 0.90 for the five subscales and r = 0.90 for the total measure. The FOSQ successfully discriminated between normal subjects and those seeking medical attention for a sleep problem (T157 = −5.88, p = 0.0001). This psychometric evaluation of the FOSQ demonstrated parameters acceptable for its application in research and in clinical practice to measure functional status outcomes for persons with DOES. Thus, the FOSQ can be used to determine how disorders of excessive sleepiness affect patients’ abilities to conduct normal activities and the extent to which these abilities are improved by effective treatment of DOES.

Johns, Murray; Hocking, Bruce

doi: 10.1093/sleep/20.10.844pmid: 9415943

Summary:Excessive daytime sleepiness in the general community is a newly recognized problem about which there is little standardized information. Our aim was to measure the levels of daytime sleepiness and the prevalence of excessive daytime sleepiness in a sample of Australian workers and to relate that to their self-reported sleep habits at night and to their age, sex, and obesity. Sixty-five percent of all 507 employees working during the day for a branch of an Australian corporation answered a sleep questionnaire and the Epworth sleepiness scale (ESS) anonymously. Normal sleepers, without any evidence of a sleep disorder, had ESS scores between 0 and 10, with a mean of 4.6 ± 2.8 (standard deviation). They were clearly separated from the “sleepy” patients suffering from narcolepsy or idiopathic hypersomnia whose ESS scores were in the range 12–24, as described previously. ESS scores >10 were taken to represent excessive daytime sleepiness, the prevalence of which was 10.9%. This was not related significantly to age (22–59 years), sex, obesity, or the use of hypnotic drugs but was related significantly but weakly to sleep-disordered breathing (frequency of snoring and apneas), the presence of insomnia, and reduced time spent in bed (insufficient sleep).

Hayduk, Roza; Flodman, Pamela; Spence, M. Anne; Erman, Milton K.; Mitler, Merrill M.

doi: 10.1093/sleep/20.10.850pmid: 9415944

Summary:An ongoing study of the genetics of narcolepsy ascertains families through a case series of narcoleptic probands using diagnostic criteria consisting of 1) clinical history of excessive somnolence, 2) a mean sleep latency on the multiple sleep latency test (MSLT) of less than 7.9 minutes, 3) the rapid eye movement (REM) sleep-related symptom of cataplexy, 4) nocturnal polysomnography ruling out sleep apnea syndrome, and 5) two or more transitions to REM sleep on the MSLT. All probands and first-degree relatives received clinical and laboratory evaluations as well as human leukocyte antigen (HLA) typing. Demographic characteristics of the 32 probands are as follows: 17 males and 15 females; mean age was 42.1 years (range 13–70 years). The polysomnographic data confirmed daytime sleepiness and increased tendency for REM sleep for the 32 probands. Nocturnal polysomnographic results are as follows: sleep latency, 3.2 minutes; total sleep time, 442 minutes. MSLT results are as follows: sleep latency, 3.1 minutes; REM latency, 6.9 minutes; number of REM periods, 3.2. HLA typing revealed the presence of the HLA haplotypes, DRB1*15 and DQB1*0602, in 21 narcoleptic probands, with two African-Americans having the DQB1*0602 but not the DRB1*15 allele. Among the 57 relatives of the 32 probands, 1/31 females and 7/26 males were found to be affected with narcolepsy (p < 0.02), which suggests a higher diagnostic rate in male relatives. The 21 probands who were positive for the DRB1*15 and DQB 1*0602 haplotypes did not differ from the 10 probands who were negative for these alleles in terms of their nocturnal sleep parameters, MSLT findings, or clinical presentation. Three families with multiple individuals affected with narcolepsy are presented. Two families have more than one affected individual who does not have the high-risk HLA haplotype. In one of these families, the disease is segregating independently of any HLA haplotype. In the third family, there is cosegregation with HLA DRB1*15 and DQB 1*0602. One family contains a pair of DNA-confirmed, monozygotic twins with narcolepsy who are discordant for cataplexy and have the HLA DR14(Dw9)/DQB1*0503 and DR4(Dw4)/DQB1 *0302 haplotypes.

Monk, Timothy H.; Buysse, Daniel J.; Billy, Bart D.; Kennedy, Kathy S.; Kupfer, David J.

doi: 10.1093/sleep/20.10.858pmid: 9415945

Summary:As part of a larger bedrest study involving various life science experiments, a study was conducted on the effects of 17 days of continuous bedrest and elimination of daylight on circadian rectal temperature rhythms, mood, alertness, and sleep (objective and diary) in eight healthy middle-aged men. Sleep was timed from 2300 to 0700 hours throughout. Three 72-hour measurement blocks were compared: ambulatory prebedrest, early bedrest (days 5–7), and late bedrest (days 15–17). Temperature rhythms showed reduced amplitude and later phases resulting from the bedrest conditions. This was associated with longer nocturnal sleep onset latencies and poorer subjectively rated sleep but with no reliable changes in any of the other sleep parameters. Daily changes in posture and/or exposure to daylight appear to be important determinants of a properly entrained circadian system.

Leproult, Rachel; Copinschi, Georges; Buxton, Orfeu; Van Cauter, Eve

doi: 10.1093/sleep/20.10.865pmid: N/A

SummarySleep curtailment constitutes an increasingly common condition in industrialized societies and is thought to affect mood and performance rather than physiological functions. There is no evidence for prolonged or delayed effects of sleep loss on the hypothalamo-pituitary-adrenal (HPA) axis. We evaluated the effects of acute partial or total sleep deprivation on the nighttime and daytime profile of Cortisol levels. Plasma Cortisol profiles were determined during a 32-hour period (from 1800 hours on day 1 until 0200 hours on day 3) in normal young men submitted to three different protocols: normal sleep schedule (2300–0700 hours), partial sleep deprivation (0400–0800 hours), and total sleep deprivation. Alterations in Cortisol levels could only be demonstrated in the evening following the night of sleep deprivation. After normal sleep, plasma Cortisol levels over the 1800–2300-hour period were similar on days 1 and 2. After partial and total sleep deprivation, plasma Cortisol levels over the 1800–2300-hour period were higher on day 2 than on day 1 (37 and 45% increases, p = 0.03 and 0.003, respectively), and the onset of the quiescent period of Cortisol secretion was delayed by at least 1 hour. We conclude that even partial acute sleep loss delays the recovery of the HPA from early morning circadian stimulation and is thus likely to involve an alteration in negative glucocorticoid feedback regulation. Sleep loss could thus affect the resiliency of the stress response and may accelerate the development of metabolic and cognitive consequences of glucocorticoid excess.

Harrison, Yvonne; Horne, James A.

doi: 10.1093/sleep/20.10.871pmid: 9415947

Summary:Historical accounts of sleep loss studies have described changes in the content and patterns of speech, although to date these claims have not been systematically studied. We examined the effects of sleep loss on the spontaneous generation of words during a verbal word fluency task and the articulation of speech during a vocalized reading task. Nine subjects underwent two counterbalanced 36-hour trials involving sleep deprivation (SD) and no sleep deprivation (NSD). After SD, there was a significant deterioration in word generation and a tendency for subjects to become fixated within a semantic category. There was a significant reduction in the subjects’ use of appropriate intonation in the voice after SD, with subjects displaying more monotonic or flattened voices. These findings are discussed in light of neuropsychological evidence concerning the functions of sleep in relation to the frontal cortex and in light of the implications for interpersonal communication in the event of sleep loss.

Silber, Michael H.; Shepard, John W.; Wisbey, Joyce A.

doi: 10.1093/sleep/20.10.878pmid: 9415948

Summary:Twenty patients with problematic restless legs syndrome (RLS) were treated with pergolide. Efficacy, dosage, side effects, and tolerance were analyzed. Fifteen patients continued treatment for a median study time of 2 years. Five patients discontinued treatment after a mean of 4.2 months. Pergolide resulted in complete or near complete control of symptoms in 45% and moderate control in 50% of patients studied. Levodopa-induced daytime augmentation resolved in all patients in whom it had been present. The mean total daily maintenance dose of pergolide was 0.23 mg. Forty percent required an additional afternoon dose. Side effects developed in 12 patients (60%) and necessitated discontinuation of treatment in five. Common side effects were nausea, dizziness, and insomnia. Daytime augmentation occurred in 27% of patients, but this was mild and usually easily controlled with a supplementary afternoon dose of pergolide. Tolerance did not develop. We conclude that pergolide is an effective second-line agent for RLS, especially following levodopa-induced daytime augmentation.

Taha, Basel H.; Morrell, Mary J.; Wekheiser, Mark; Badr, M. Safwan

doi: 10.1093/sleep/20.10.883pmid: N/A

Summary:We developed an inexpensive and efficient method for simultaneously digitizing respiratory signals and fiber-optic images of the upper airway. The main components of the system are a fiber-optic scope, a charge coupled device video camera, and a personal computer equipped with a frame grabber and an A/D board. The frame grabber digitizes images at five frames per second while the A/D board samples six respiratory signals at 25 samples per second. Digitized images are saved only in the event that the user instructs the computer to do so in order to limit disk space requirements. A circular buffering technique provides continuous storage of the most recent 50 frames in frame grabber memory. This feature gives the user up to 10 seconds, following the beginning of a respiratory event, to initiate the saving of images to computer hard disk. A postacquisition program displays the data acquired during the sleep study and allows the user to interactively select images for subsequent upper airway area measurement. This system enables us to observe and quantify the dynamics of the upper airway during different breathing conditions with minimal time and cost. It is also a potential clinical tool to use to determine the site of obstruction during sleep in patients with obstructive sleep apnea.

Kimura, Kaku; Tachibana, Naoko; Aso, Toshihiko; Kimura, Jun; Shibasaki, Hiroshi

doi: 10.1093/sleep/20.10.891pmid: 9415950

Summary:Various neurodegenerative diseases have been reported to be associated with rapid eye movement (REM) sleep behavior disorder (RBD). This is the first report of a patient with corticobasal degeneration (CBD) associated with subclinical RBD. A 72-year-old woman was admitted complaining of fine tremor of the right hand and weakness of the right lower extremity. She was diagnosed as having CBD on the basis of clinical features and neuroimaging studies. Her family noticed snoring and increase in sleep talk, but they did not regard them as pathological. All-night polysomnography (PSG) revealed REM sleep without atonia (RWA) during which 14 episodes of talking and singing were observed. They ranged from the utterance of one word to that of comprehensible words of a song for about 3 minutes accompanied by various nonpurposeful movements of the mouth, hands, and limbs. These episodes were not associated with any sleep-disturbed breathing. Future PSG studies on CBD patients together with postmortem analysis of brain stem structures that are crucial for generating REM sleep-related atonia are warranted for further understanding of the pathophysiological mechanism of RBD.