Luciana Palombini

Sleep and wakefulness in somnambulism A spectral analysis study

OBJECTIVE The sleep structure and the dynamics of EEG slow-wave activity (SWA) were investigated in 12 young adults and age- and gender-matched controls. METHODS Polysomnography was performed in subjects with well-documented chronic sleepwalking and in matched controls. Blinded visual scoring was performed using the international criteria from the Rechtschaffen and Kales atlas [A manual of standardized technology, techniques and scoring systems for sleep stages of human subjects. Los Angeles: UCLA Brain Information Service, Brain Research Institute, 1968.] and by determining the presence of microarousals as defined in the American Sleep Disorders Association (ASDA) atlas [Sleep 15 (1992) 173.]. An evaluation of SWA overnight was performed on total nocturnal sleep to determine if a difference existed between groups of subjects, since sleepwalking usually originates with slow-wave sleep. Investigation of the delta power in successive nonoverlapping 4-second windows in the 32 seconds just prior to EMG activity associated with a confusional arousal was also conducted. One central EEG lead was used for all analyses. RESULTS Somnambulistic individuals experienced more disturbed sleep than controls during the first NREM-REM sleep cycle. They had a higher number of ASDA arousals and presented lower peak of SWA during the first cycle that led to a lower SWA decline overnight. When the investigation focused on the short segment immediately preceding a confusional arousal, they presented an important increase in the relative power of low delta (0.75-2 Hz) just prior to the confusional arousal. CONCLUSION Sleepwalkers undergo disturbed nocturnal sleep at the beginning of the night. The increased power of low delta just prior to the confusional arousal experienced may not be related to Stages 3-4 NREM sleep. We hypothesize that it may be translated as a cortical reaction to brain activation.

Chronic insomnia, postmenopausal women, and sleep disordered breathing: Part 1. Frequency of sleep disordered breathing in a cohort

OBJECTIVES A cohort of postmenopausal women complaining of chronic insomnia for over 6 months and free of hypnotic intake was recruited mostly from the community. Three hundred and ninety-four women were included. The following questions were addressed: How many presents sleep disordered breathing (SDB)? Which type of SDB (upper airway resistance syndrome [UARS] or obstructive sleep apnea syndrome [OSAS]) is the most frequent? Is there a specific upper airway anatomical abnormality in SDB patients predisposing to the syndrome? POPULATION Subjects were recruited in the community or referred by the Sleep Clinic and all had complaint of chronic poor sleep. METHODOLOGY First step. Questionnaires, visual analog scales, clinical interview, clinical evaluation with work-up, actigraphy, and ambulatory monitoring were used. Second step. Otolaryngologic evaluation, ambulatory sleep monitoring, and reading of results were used. Subjects negative for SDB at ambulatory monitoring had polysomnography (PSG) with pressure transducer/nasal cannula system and esophageal manometry measurements. RESULTS Population. Three hundred and ninety-four individuals responded to all entry criteria. Ambulatory monitoring identified 194 subjects with OSAS. Two hundred individuals were not recognized with SDB and were submitted to PSG. This further testing showed that 68 subjects had normal breathing, 62 had UARS, and 100 mild OSAS. Based on otolaryngological evaluation, subjects were classified based on the presence or absence of narrow upper airway, and the location of narrowing was assessed. CONCLUSION A total of 326 postmenopausal women complaining of chronic insomnia had a SDB, usually with low apnea-hypopnea index (AHI). This total represents about 83% of the studied women. Questions of the role of SDB in the complaint of chronic insomnia are raised.

Stroke and treatment with nasal CPAP

Stroke patients present a high prevalence of obstructive sleep apnea (OSA) and those with OSA have a higher mortality after 1 year and poorer functional outcome compared with others. The aim of this study was to prospectively evaluate the acceptance of nasal continuous positive airway pressure (CPAP) by recent stroke patients with OSA. Recruitment of non‐comatose stroke patients with sufficient consciousness for diagnostic evaluation of OSA was performed and they were treated at home with nasal CPAP after hospital calibration and training on the usage of CPAP. Initial evaluation and regular follow‐up of the home trial of auto‐CPAP was carried out for a duration of 8 weeks. Of 50 initially recruited patients, 32 (100%) responded to the minimum cognitive criteria but seven patients (22%) only used nasal CPAP for 8 weeks. Subject dropout was related to difficulties with CPAP usage as perceived by patient and family members, facial weakness, motor impairment and increase difficulties and discomfort with usage of full‐face mask. The majority of OSA stroke patients rejected CPAP treatment. Better education and support of patients and families, and special training sessions in rehabilitation services, will be needed to improve compliance.

Preliminary observations on the effects of sleep time in a sleep restriction paradigm

OBJECTIVE To evaluate of the effect of 7 days of sleep restriction--with sleep placed at the beginning of night or early morning hours - on sleep variables, maintenance of wakefulness test, and serum leptin. METHODS After screening young adults with questionnaires and actigraphy for 1 week, eight young adult males were recruited to participate in a sleep restriction study. The subjects were studied for baseline data for 2.5 days, with 8.5 h per night in bed, and then over 7 days of sleep restriction to 4 h per night with a 22:30 h bedtime for half the group and a 02:15 h bedtime for the other half. At the end of study, after one night of ad libitum sleep, subjects again had 2 days of 8.5 h in bed. Wakefulness was continuously verified and tests, including Maintenance of Wakefulness (MWT), were performed during the scheduled wake time. Blood was drawn six times throughout the 24 h of the 7th day of sleep restriction and after 2 days of the post-restriction schedule. RESULTS There was individual variability in response to sleep restriction, but independent of group distribution, MWT was significantly affected by sleep restriction, with the early morning sleep group having less decrease in MWT score. Sleep efficiency was also better in this group, which also had shorter sleep latency. Independent of group distribution there was a greater increase in the percentage of slow wave sleep than rapid eye movement sleep, despite a clear internal variability and variability between subjects. Peak serum leptin was significantly decreased with 7 days of sleep restriction for all subjects. CONCLUSION Sleep restriction to 4 h affected all subjects, but there were individual and group differences in MWT and sleep data. In this group of young adult males (mean age 19 years), there was a better overall adaptation to the early morning sleep, perhaps related to the general tendency in most adolescents to present some phase-delay during late teen-aged years.

A clinical investigation of obstructive sleep apnea syndrome (OSAS) and upper airway resistance syndrome (UARS) patients.

Objective: (i) Evaluation of the clinical differences and similarities presented by patients diagnosed as OSAS and UARS subjects. (ii) Evaluation of the ability of a sleep disorders specialist to dissociate the two syndromes based upon clinical evaluation.Population: 314 subjects were included. They were referred to a sleep disorders clinic with complaints of loud snoring during a 3 month period.Method: The evaluation consisted of: (i) Clinical interview and evaluation. (ii) Administration of validated questionnaires (Sleep Disorders Questionnaire and Epworth Sleepiness Scale). (iii) Establishment of clinical diagnostic and results of polygraphic recording.Results: After clinical evaluation and polygraphic recordings (performed within 3 weeks of initial evaluation) patients were subdivided into two groups: 176 OSAS and 128 UARS. The misclassification of patients by specialists correlated with body mass index (BMI) measurement, with an over classification of patient as OSAS when a high BMI was noted and vice-versa for UARS. The only significant difference between OSAS and UARS patients was an older age and a wider neck circumference in the OSAS group than in UARS patients.Conclusion: Clinical presentation including daytime sleepiness complaint and ESS score is similar for patients with and without drop of oxygen saturation below 90% during sleep. There was always a male predominance within both syndromes, but more women were diagnosed with UARS than with OSAS.

Effect of smoking habits on sleep

To evaluate the effect of smoking habits on sleep, data from 1492 adults referred to the Sleep Institute were accessed and divided into 3 categories of smoking status: current, former and non-smokers. Categories of pack-years (<15 and > or =15) defined smoking severity. The association of smoking status and smoking severity with sleep was analyzed for sleep parameters, especially apnea and hypopnea index (AHI) > or =5, more than 5% of total sleep time (TST) spent with oxyhemoglobin saturation (SaO2) <90%, and arousal index. The arousal index was higher among current (21 +/- 17) and former smokers (20 +/- 17) than non-smokers (17 +/- 15; P < 0.04). Former smokers had a higher percent of TST at SaO2 <90% than non-smokers (9 +/- 18 vs 6 +/- 13; P < 0.04). Former smokers with pack-years > or =15 compared to <15 exhibited higher AHI (22 +/- 24 vs 16 +/- 21; P < 0.05) and arousal index (22 +/- 19 vs 18 +/- 15; P < 0.05). Current smokers with pack-years > or =15 compared to <15 exhibited higher arousal index (23 +/- 18 vs 18 +/- 16; P < 0.05) and percent of TST at SaO2 <90% (11 +/- 17 vs 6 +/- 13; P < 0.05). Smoking status and pack-years were not associated with AHI > or =5 on logistic regression analysis, but current smokers with pack-years > or =15 were 1.9 times more likely to spend more than 5% of TST at SaO2 <90% than non-smokers (95%CI = 1.21-2.97; P = 0.005). The variability of arousal index was influenced by gender, AHI and current smokers with pack-years > or =15 (all P < 0.01). Smoking habits seem to be associated with arousal and oxyhemoglobin desaturation during sleep, but not with AHI. The effect was more pronounced in current than former smokers.

Cervical positioning for reduction of sleep-disordered breathing in mild-to-moderate OSAS.

The objective of this study was to assess whether cervical positioning could improve mild to moderate cases of the obstructive sleep apnea syndrome (OSAS). Eighteen subjects recruited from a tertiary sleep disorders clinic population with mild to moderate cases of OSAS were evaluated using a custom-fitted cervical pillow designed to increase upper airway caliber by promoting head extension. The subjects used their usual pillows during two consecutive recorded baseline nights in our laboratory. They then used the cervical pillow for 5 days at home and returned for 2 consecutive recorded nights at our laboratory to use the cervical pillow. During the nights in our laboratory, the subjects completed questionnaires, were videotaped to record head and body position, and had full polysomnography. The subjects had a significant trend toward improvement in their respiratory disturbance indices with use of the cervical pillow, despite spending more time in the supine position and having similar amounts of REM sleep in the baseline and experimental conditions. They also had nonsignificant trends toward improvements in their sleep efficiency and subjective depth of their sleep as well as significantly fewer arousals and awakenings in the experimental compared with the baseline condition. We propose that cervical positioning (i.e., head extension) with a custom-fitted cervical pillow provides a simple, noninvasive, and comfortable means of reducing sleep-disordered breathing in patients with mild to moderate OSAS.

Musculoskeletal Pain as a Marker of Health Quality. Findings from the Epidemiological Sleep Study among the Adult Population of São Paulo City

Background We are witnessing the growth of urban populations, particularly in the developing world. São Paulo, the largest city in South America, continues to grow, and this growth is dramatically effecting the environment and human health. The aim of this study was to estimate the point prevalence of chronic pain in São Paulo city dwellers and to explore the influence of aspects related to urbanicity. Methods A two-stage cluster randomized sample included 1100 individuals of the city of Sao Paulo, representing the population proportionally in terms of gender, age and social classes in 2007. For this observational cross-sectional study, the household sample was interviewed using validated questionnaires for sociodemographic aspects, the Beck inventories for anxiety and depression, the WHOQoL-REF for quality of life, the Chalder Fatigue Scale. Musculoskeletal pain was defined as diffuse pain or pain located in the back, joints or limbs. Data regarding sleep complaints and polysomnography were obtained from the Epidemiologic Sleep Study conducted in São Paulo city in 2007. Results The prevalence estimate of chronic musculoskeletal pain was approximately 27%, with a female/male ratio of approximately 2.6/1. The predictors were being in the age-range of 30–39 years, low socioeconomic and schooling levels, obesity, sedentarism, fatigue, non-restorative sleep, daytime sleepiness, poor sleep quality, poor life quality, anxiety and depression symptoms. Psychological wellbeing was the main discriminator between responders with chronic musculoskeletal pain and the controls, followed by depression for the participants with poor psychological wellbeing, and fatigue, for the remaining ones. Insomnia syndrome was the third-level discriminator for those with fatigue, whereas sleep quality for those without fatigue. Conclusions Musculoskeletal pain was frequently reported by São Paulo city dwellers and its correlates with psychological and sleep aspects are suggestive of a response to urbanicity. Trial Registration ClinicalTrials.gov NCT00596713

Treatment of obstructive sleep apnea syndrome associated with stroke

The association between sleep-disordered breathing and stroke has been a subject of increased interest and research. Obstructive sleep apnea (OSA) is an important risk factor for stroke incidence and mortality. Moreover, OSA is a common clinical outcome after stroke, directly influencing the patients recovery. The treatment of choice for OSA is positive airway pressure (PAP) support and the PAP appliance is considered the most recommended clinical management for the treatment of patients with cardiovascular complications. However, the implementation of PAP in stroke patients remains a challenge, considering the increased frequency of motor and language impairments associated with the cerebrovascular event. In the present study, we reviewed the main findings describing the association between stroke and OSA treatment with continuous positive airway pressure. We also discussed the types of OSA treatment, the different options and indications of PAP treatment, PAP adherence and the clinical outcomes after treatment.

The STOP-BANG questionnaire was a useful tool to identify OSA during epidemiological study in São Paulo (Brazil) ☆

Universidade Federal de Sao Paulo UNIFESP, Dept Psicobiol, Disciplina Biol & Med Sono, Sao Paulo, Brazil