SLEEP

Nowak, Magdalena; Kornhuber, Johannes; Meyrer, Robert

doi: 10.1093/sleep/29.12.1521pmid: 17252882

AbstractStudy Objective:Controversy surrounds the pathogenesis of neurocog-nitive daytime dysfunction exhibited by patients with o bstructive sleep apnea syndrome (OSAS). Underlying brain dysfunctions and damage have long been suspected as a cause of some of this impairment. Neuroimaging has enabled scientists to test these long-held theories. This paper is based on a comprehensive review of recent publications on neuroimaging studies in this area. It seeks to highlight results of recent research, which suggest connections between persistent neurocognitive daytime impairment of executive functions, underlying signs of cerebral metabolic impairment and neurodegeneration, considering possible cerebrovascular impairment in OSAS patients. We propose the existence of a neurodegenerative process.

Choi, Jong-Bae; Nelesen, Richard; Loredo, José S.; Mills, Paul J.; Ancoli-Israel, Sonia; Ziegler, Michael G.; Dimsdale, Joel E.

doi: 10.1093/sleep/29.12.1531pmid: 17252883

AbstractStudy Objectives:Daytime sleepiness is a common clinical presentation in both obstructive sleep apnea (OSA) and cardiovascular diseases. The purpose of this study was to assess the relationship between degree of subjective daytime sleepiness and cardiac performance in patients with obstructive sleep apnea.Design:Observational studySetting:General Clinical Research CenterPatients:The study sample was comprised of 86 patients (68 men and 18 women) with an average age of 47 years. All were suspected of having obstructive sleep apnea and underwent confirmatory diagnostic polysomnography (respiratory disturbance index ≥ 15).Measurements and Results:Stroke volume and cardiac output were measured using impedance cardiography and corrected for body surface area to yield stroke index and cardiac index. Daytime sleepiness was quantified using the Epworth Sleepiness Scale. A higher Epworth Sleepiness Scale score, suggesting more daytime sleepiness, was significantly related to lower stroke index and cardiac index. In multiple regression analyses, the relationships of Epworth Sleepiness Scale score with both stroke index and cardiac index were significant (p < .05), even after controlling for age, sex, ethnicity, respiratory disturbance index, and mean sleep oxygen saturation.Conclusions:These results suggest that daytime sleepiness is independently associated with decreases in cardiac function as assessed by impedance cardiography in patients with obstructive sleep apnea.

Li, Hsueh-Yu; Wang, Pa-Chun; Lee, Li-Ang; Chen, Ning-Hung; Fang, Tuan-Jen

doi: 10.1093/sleep/29.12.1537pmid: 17252884

AbstractStudy Objective:To evaluate and compare outcomes of uvulopalato-pharyngoplasty (UPPP) for obstructive sleep apnea/hypopnea syndrome (OSAHS) using anatomy- and severity-based staging systems.Design:Prospective design with a retrospective review.Setting:A tertiary-care, sleep disorder referral center.Patients:In total, 110 patients with OSAHS (105 men, 5 women; mean age, 43 years; apnea-hypopnea index, 44.4 ± 28.8 events per hour; body mass index, 27.1 ± 3.3 kg/m2).Measurements:An anatomy-based staging system (stages I–IV) was used to classify patients with OSAHS by examining tongue-palate position, tonsil size, body mass index, and craniofacial deformities. Patients were also classified as having mild, moderate, moderate-severe, or severe OSAHS based on preoperative apnea-hypopnea index from polysomnography (a severity-based staging system). Surgical success was defined as a 50% or greater reduction in the apnea-hypopnea index and a postoperative apnea-hypopnea index of less than 20 events per hour.Intervention:UPPP was performed in all patients.Results:The overall success rate of UPPP was 78%. Success rates for mild (90%), moderate (73%), moderate-severe (81%), and severe (74%) diseases were similar (p = .10). Conversely, success rates for patients with anatomy-based stages I, II, III, and IV were 100%, 96%, 65%, and 20%, respectively; these rates were significantly different (p < .001). Changes in apnea-hypopnea index were significantly correlated with Friedman tongue position (FTP)(r = −0.33, p = .0004) and tonsil size (r = −0.37, p < .0001). The FTP (odds ratio = 0.43, SE = 0.13, p = .005, 95% confidence interval = 0.24–0.78) and tonsil size (odds ratio = 3.13, SE = 1.53, p = .02, 95% confidence interval = 1.20–8.17), but not the severity-based staging (odds ratio = 0.77, SE=0.18, p = .283, 95% confidence interval = 0.49–1.23), were predictive of surgical success.Conclusion:The anatomy-based staging system predicted UPPP outcomes more effectively than did the severity-based staging. The anatomy-based staging system facilitates good case-selection information for counseling patients before UPPP surgery.

Kaneita, Yoshitaka; Ohida, Takashi; Osaki, Yoneatsu; Tanihata, Takeo; Minowa, Masumi; Suzuki, Kenji; Wada, Kiyoshi; Kanda, Hideyuki; Hayashi, Kenji

doi: 10.1093/sleep/29.12.1543pmid: 17252885

AbstractStudy Objectives:Although a number of previous studies have examined the prevalence of insomnia among adolescents, there have been very few nationwide studies. The objectives of this nationwide study were to clarify the prevalence of insomnia, its symptoms, and associated factors among Japanese adolescents.Design and Setting:This study was designed as a cross-sectional sampling survey. The targets were junior and senior high schools throughout Japan. Sample schools were selected by cluster sampling. Self-reported anonymous questionnaires were sent to schools for all students to fill out.Participants:A total of 103,650 adolescents responded, and 102,451 questionnaires were subjected to analysis.Intervention:N/AMeasurements and Results:The prevalence of difficulty initiating sleep, difficulty maintaining sleep, and early morning awakening was 14.8%, 11.3%, and 5.5%, respectively. Insomnia was defined as the presence of one or more of these three symptoms. The prevalence of insomnia was 23.5%. Multivariate analyses revealed that, among junior high school students, male sex, poor mental health, skipping breakfast, drinking alcohol, smoking, not participating in extracurricular activities, and late bedtime had significantly higher odds ratios for insomnia. Among senior high school students, the same characteristics were associated with a significantly higher odds ratio for insomnia, as was the additional factor of having no intent to study at university.Conclusion:Insomnia in Japanese adolescents is common and associated with multiple factors. The results of this study suggest the need for comprehensive program to prevent insomnia in Japanese adolescents.

McCrae, Christina S.; Rowe, Meredeth A.; Dautovich, Natalie D.; Lichstein, Kenneth L.; Durrence, Heith H.; Riedel, Brant W.; Taylor, Daniel J.; Bush, Andrew J.

doi: 10.1093/sleep/29.12.1551pmid: 17252886

AbstractStudy Objectives:Common sleep hygiene practices were examined in 2 community-based samples of older adults to determine which practices differentiated 4 sleep subgroups: noncomplainers without insomnia symptoms, complainers without insomnia symptoms, noncomplainers with insomnia symptoms, and complainers with insomnia symptoms.Design:Two weeks of sleep diaries provided napping and bed/out-of-bed time variability data. A retrospective questionnaire provided data on caffeine, cigarette, and alcohol usage. Recruitment involved random digit dialing (Sample 1) and advertisements (Sample 2).Setting:Memphis, TN area (Sample 1); Gainesville, FL area (Sample 2).Participants:310 individuals 60-96 years (Sample 1); 103 individuals 60–89 years (Sample 2).Inventions:N/A.Measurements and Results:Older individuals with sleep complaints did not report engaging in poorer sleep hygiene practices than those without complaints with the exception of frequency of napping. For Sample 1 only, complainers reported napping on 1.5-2.0 more days per week than non-complainers. Sleep subgroups in both samples did not differ for the other sleep hygiene practices studied.Conclusions:Overall, sleep hygiene behaviors did not differentiate the 4 sleep subgroups. The efficacy of sleep hygiene as a therapy for late life insomnia appears questionable in this context. Both complaining sleep subgroups napped more frequently than both noncomplaining subgroups in Sample 1. Additional research is needed to clarify the clinical implications of nap frequency as these results did not replicate in Sample 2, and the impact of napping on nighttime sleep remains unclear. Inconsistencies with previous research in younger samples support the need for more research specifically targeting older individuals' sleep patterns and behaviors.

Malow, Beth A.; Marzec, Mary L.; McGrew, Susan G.; Wang, Lily; Henderson, Lynnette M.; Stone, Wendy L.

doi: 10.1093/sleep/29.12.1563pmid: 17252887

AbstractStudy Objectives:To relate parentally reported sleep concerns in autism spectrum disorders (ASD) to polysomnographic (PSG) findings and measures of daytime behavior and autism symptomatology.Design:Cross-sectional study involving validated questionnaires, sleep histories and diaries, 2 nights of PSG, and the Autism Diagnostic Observation Schedule (ADOS).Setting:Vanderbilt University General Clinical Research Center Sleep CoreParticipants:21 children with ASD and 10 typically developing (TD) children, aged 4–10 years. Children were free of psychotropic medications, with no history of mental retardation or epileptic seizures.Interventions:N/AMeasurements and Results:Children with ASD were defined as “good sleepers” (10 children) and “poor sleepers” (11 children) on the basis of parental report; the age-comparable TD children were all reported by their parents to be good sleepers. Poor sleepers with ASD showed prolonged sleep latency and decreased sleep efficiency on night 1 of PSG and differed on insomnia-related subscales of the Children's Sleep Habits Questionnaire (CSHQ; increased sleep onset delay and decreased sleep duration). The good sleepers with ASD did not differ from the TD children in sleep architecture or on CSHQ domains. As compared with ASD good sleepers, the ASD poor sleepers also had higher scores related to affective problems on the Child Behavior Checklist and more problems with reciprocal social interaction on the ADOS.Conclusions:Parentally reported sleep concerns of insomnia in children with ASD are substantiated by validated sleep questionnaires and by PSG. Furthermore, good sleepers with ASD showed fewer affective problems and better social interactions than ASD poor sleepers.

Sangal, R. Bart; Owens, Judith; Allen, Albert J.; Sutton, Virginia; Schuh, Kory; Kelsey, Douglas

doi: 10.1093/sleep/29.12.1573pmid: 17252888

AbstractStudy Objectives:This study compared the effects of atomoxetine and methylphenidate on the sleep of children with attention-deficit/hyperactivity disorder (ADHD). This study also compared the efficacy of these medications for treating ADHD in these children.Design:Randomized, double-blind, crossover trial.Setting:Two sleep disorders centers in the United States; 1 in a private-practice setting and 1 in a hospital setting.Patients:85 children diagnosed with ADHD.Interventions:Twice-daily atomoxetine and thrice-daily methylphenidate, each for approximately 7 weeks.Measurements and Results:Relative to baseline, the actigraphy data indicated that methylphenidate increased sleep-onset latency significantly more than did atomoxetine (39.2 vs 12.1 minutes, p < .001). These results were consistent with the polysomnography data. Child diaries indicated that it was easier to get up in the morning, it took less time to fall asleep, and the children slept better with atomoxetine, compared with methylphe-nidate. Parents reported that it was less difficult getting their children up and getting them ready in the morning and that the children were less irritable, had less difficulty getting ready for bed, and had less difficulty falling asleep with atomoxetine, compared with methylphenidate. There were no significant differences between medications using the main measures of efficacy for ADHD treatment. Atomoxetine was superior on some secondary ADHD treatment-efficacy measures, based on parent reports. The only significant differences in treatment-emergent adverse events were greater incidence of decreased appetite and greater incidence of insomnia with methylphenidate.Conclusions:Patients receiving twice-daily atomoxetine had shorter sleep-onset latencies, relative to thrice-daily methylphenidate, based on objective actigraphy and polysomnography data. Although both medications decreased nighttime awakenings, the decrease was greater for methylphenidate.

Ferri, Raffaele; Zucconi, Marco; Manconi, Mauro; Bruni, Oliviero; Ferini-Strambi, Luigi; Vandi, Stefano; Montagna, Pasquale; Mignot, Emmanuel; Plazzi, Giuseppe

doi: 10.1093/sleep/29.12.1587pmid: 17252889

AbstractStudy Objectives:To analyze periodic leg movements (PLM) during sleep in patients with narcolepsy and compare the results with those obtained in normal controls and subjects with restless legs syndrome (RLS).Methods:We recruited 40 HLA DQB1*0602-positive patients with narcolepsy/cataplexy, 22 with RLS, and 22 controls. The time structure of their polysomnographically recorded LMs was analyzed by means of an approach particularly able to consider their periodicity.Measurements and Results:Nineteen patients with narcolepsy had a PLM index greater than 15. The distribution of inter-LM intervals was clearly bimodal in RLS and narcoleptics, with 1 peak at 2 to 4 seconds and another at around 22 to 26 seconds; in the range 22 to 40 seconds, patients with RLS had values significantly higher than patients with narcolepsy. All periodicity parameters were significantly lower in the narcolepsy group. Finally, the distribution of the number of PLM per hour of sleep was bell shaped in normal controls and patients with narcolepsy, whereas patients with RLS showed a progressive decrease throughout the night.Conclusion:Most narcoleptic patients show a high number of LMs that are significantly less periodic than those of patients with RLS. PLM are in functional interrelationship with the cyclic alternating pattern, which is reduced in patients with narcolepsy; decreased arousal fluctuations during sleep may be one of the factors influencing the reduction in periodicity of LMs during sleep in narcolepsy.

Scalise, Anna; Desiato, Maria Teresa; Gigli, Gian Luigi; Romigi, Andrea; Tombini, Mario; Marciani, Maria Grazia; Izzi, Francesca; Placidi, Fabio

doi: 10.1093/sleep/29.12.1595pmid: 17252890

AbstractStudy Objective:Sleep deprivation (SD) is known to facilitate both seizures and interictal epileptiform abnormalities. For this reason, it is often used in the routine diagnostic workup of epileptic patients as an activating procedure for eliciting epileptiform and/or seizure patterns in their EEGs. In order to evaluate the effects of SD on cortical excitability, we studied the effects of sleep loss on healthy subjects by transcranial magnetic stimulation (TMS).Design and Participants:Seven normal subjects underwent TMS examination in baseline condition and after total sleep deprivation. The TMS investigation included two protocols: a) the evaluation of motor evoked potential and silent period parameters recorded in response to single-pulse magnetic stimulation; and b) the evaluation of the time course of intracortical motor activity tested with paired-pulse TMS applied at inter-stimulus intervals of 1–6 ms.Setting:Clinical neurophysiology laboratory in a general hospital.Interventions:NoneResults:After SD, the principal finding observed using single-pulse TMS was a decrease of the silent period duration, whereas a reduction of the intracortical inhibition, in particular at inter-stimulus intervals 1 and 2 ms, was found, using the paired-pulse TMS.Conclusion:Our findings suggest that SD may modify cortical excitability, seen as the balance between inhibitory and excitatory cortical phenomena, which could reduce the epileptic threshold.

Kirk, Valerie G.; Batuyong, Eldridge D.; Bohn, Shelly G.

doi: 10.1093/sleep/29.12.1601pmid: 17252891

AbstractIntroduction:Transcutaneous monitoring and capnography are 2 surrogate methods of measuring arterial carbon dioxide levels employed by pediatric sleep laboratories. Both techniques are noninvasive, validated, and quantitative indirect predictors of arterial carbon dioxide level, and both have been widely adopted for use during pediatric and adult polysomnography (PSG). We hypothesized that there would be close agreement between the two techniques when compared in a pediatric population.Methods:Children referred for diagnostic polysomnography to the Pediatric Sleep Laboratory at the Alberta Children's Hospital from June 2000 to October 2003 were included. All subjects underwent an overnight computerized PSG as per American Thoracic Society standards, including both transcutaneous and end-tidal monitoring. A registered PSG technician manually scored studies and eliminated all CO2 data that was not interpretable. Total “uninterpretable data” time was calculated for both channels. Statistical analysis of the level of agreement between transcutaneous and end-tidal signals was performed using a Bland-Altman analysis.Results:The PSG studies of 609 children (363 males), mean age 7.9 ± 4.6 years (range 0.1–18.4), were reviewed. On average, interpretable data was available for 61.8% ± 35.1% and 71.5% ±25.2 % of total recording time from the end-tidal and transcutaneous channels respectively. The maximum and mean CO2 measurements obtained by both devices showed close agreement with a mean difference of 0.1+/−5.4 mm Hg and 0.6+/−3.9 mm Hg respectively.Conclusion:Transcutaneous and end-tidal carbon dioxide monitoring during polysomnography are well tolerated and provide interpretable and comparable results in the majority of children.