IL-17 is a pro-inflammatory mediator that is believed to play a critical role in regulating tissue inflammation during asthma, COPD, as well as other inflammatory disorders. The level of expression of IL-17 has been shown to be upregulated in lung bronchial tissue of asthmatic patients. Several reports have provided further evidence that this cytokine could play a key role in enhancing the migration of inflammatory as well as structural cells of the bronchial lung tissue during asthma and COPD. B cell infiltration to sites of inflammation during inflammatory disorders such as bowel disease, asthma and COPD has been reported. Accordingly, in this study we hypothesized that IL-17 may exert a chemotactic effect on primary B cells during asthma. We observed that B cells from asthmatic patients expressed significantly higher levels of IL-17RA and IL-17RC, compared to those of healthy subjects. Using an in-vitro migration assay, B cells were shown to migrate towards both IL-17A and IL-17F. Interestingly, blocking IL-17A and IL-17F signaling using either anti-IL-17R antibodies or MAP kinase inhibitors prevented in vitro migration of B cell towards IL-17. These observations indicate a direct chemotactic effect of IL-17 cytokines on primary peripheral blood B cells with higher effect being on asthmatic B cells. These findings revealed a key role for IL-17 in enhancing the migration of B cells to the lung tissue during asthma or COPD.
Sleep–wake disturbances have frequently been reported in bipolar disorder and schizophrenia, and are considered to be caused by an underlying circadian rhythm disorder. The study presented here was designed to investigate the existence of Per3 polymorphism in bipolar disorder type I (BD-I) and schizophrenic patients in South India.
Blood samples were collected from 311 BD-I patients, 293 schizophrenia patients, and 346 age- and sex-matched normal controls. Per3 genotyping was performed on DNA by polymerase chain reaction using specific primers.
An increased prevalence of five repeat homozygotes was seen in BD-I patients as compared with healthy controls (odds ratio =1.72 [95% confidence interval: 1.08–2.76, P=0.02]). In BD-I patients, the frequency of the five repeat allele was higher (allele frequency =0.41), and that of the four repeat allele lower (allele frequency =0.36) (χ2=4.634; P<0.03) than in the control group. No significant association was observed in the allele frequencies of four and five repeat alleles in schizophrenia patients when compared with controls.
The occurrence of the five repeat allele of Per3 may be a risk factor for BD-I onset in this ethnic group.
circadian rhythms; clock genes; Per3 polymorphism; bipolar disorder; schizophrenia
We aimed to assess the effect of Islamic intermittent fasting, during and outside of Ramadan, on plasma levels of leptin and ghrelin while controlling for several potential confounding variables. Eight healthy male volunteers with a mean age of 26.6±4.9 years reported to the sleep disorders center (SDC) at King Saud University on four occasions: 1) adaptation; 2) 4 weeks before Ramadan while performing Islamic fasting for 1 week (baseline fasting) (BLF); 3) 1 week before Ramadan (non-fasting baseline) (BL); and 4) during the second week of Ramadan while fasting. Plasma leptin and ghrelin levels were measured using enzyme-linked immunoassays at 22:00, 02:00, 04:00, 06:00, and 11:00. During BLF, there were significant reductions in plasma leptin concentrations at 22:00 and 02:00 compared with the baseline concentrations (at 22:00: 194.2±177.2 vs. 146.7±174.5; at 02:00: 203.8±189.5 vs. 168.1±178.1; p<0.05). During Ramadan, there was a significant reduction in plasma leptin levels at 22:00 (194.2±177.2 vs. 132.6±130.4, p<0.05). No significant difference in plasma ghrelin concentrations was detected during the BL, BLF, or Ramadan periods. Cosinor analyses of leptin and ghrelin plasma levels revealed no significant changes in the acrophases of the hormones during the three periods. The nocturnal reduction in plasma leptin levels during fasting may be the result of the changes in meal times during fasting.
We conducted this national survey to quantitatively assess sleep medicine services in the Kingdom of Saudi Arabia (KSA) and to identify obstacles that specialists and hospitals face, precluding the establishment of this service.
MATERIALS AND METHODS:
A self-administered questionnaire was designed to collect the following: General information regarding each hospital, information regarding sleep medicine facilities (SFs), the number of beds, the number of sleep studies performed and obstacles to the establishment of SFs. The questionnaire and a cover letter explaining the study objectives were mailed and distributed by respiratory care practitioners to 32 governmental hospitals and 18 private hospitals and medical centers in the KSA.
The survey identified 18 SFs in the KSA. The estimated per capita number of beds/year/100,000 people was 0.11 and the per capita polysomnography (PSG) rate was 18.0 PSG/year/100,000 people. The most important obstacles to the progress of sleep medicine in the KSA were a lack of trained sleep technologists and a lack of sleep medicine specialists.
The sleep medicine services provided in the KSA have improved since the 2005 survey; however, these services are still below the level of service provided in developed countries. Organized efforts are needed to overcome the identified obstacles and challenges to the progress of sleep medicine in the KSA.
Polysomnography; quantitative assessment; sleep disorders center; sleep medicine service; sleep technologists
Limited information is available regarding sleep medicine education worldwide. Nevertheless, medical education has been blamed for the under-recognition of sleep disorders among physicians. This study was designed to assess the knowledge of Saudi undergraduate medical students about sleep and sleep disorders and the prevalence of education on sleep medicine in medical schools as well as to identify the obstacles to providing such education.
We surveyed medical schools that were established more than 10 years ago, asking fourth- and fifth-year medical students (men and women) to participate. Seven medical schools were selected. To assess knowledge on sleep and sleep disorders, we used the Assessment of Sleep Knowledge in Medical Education (ASKME) Survey, which is a validated 30-item questionnaire. The participants were separated into two groups: those who scored ≥60% and those who scored <60%. To assess the number of teaching hours dedicated to sleep medicine in the undergraduate curricula, the organizers of the major courses on sleep disorders were contacted to obtain the curricula for those courses and to determine the obstacles to education.
A total of 348 students completed the survey (54.9% male). Among the participants, 27.7% had a specific interest in sleep medicine. More than 80% of the study sample had rated their knowledge in sleep medicine as below average. Only 4.6% of the respondents correctly answered ≥60% of the questions. There was no difference in the scores of the respondents with regard to university, gender, grade-point average (GPA) or student academic levels. Only five universities provided data on sleep medicine education. The time spent teaching sleep medicine in the surveyed medical schools ranged from 0-8 hours with a mean of 2.6 ±2.6 hours. Identified obstacles included the following: (1) sleep medicine has a lower priority in the curriculum (53%) and (2) time constraints do not allow the incorporation of sleep medicine topics in the curriculum (47%).
Medical students in the surveyed institutions possess poor knowledge regarding sleep medicine, which reflects the weak level of education in this field of medicine. To improve the recognition of sleep disorders among practicing physicians, medical schools must provide adequate sleep medicine education.
Sleep medicine; Education; ASKME survey; Medical schools; Medical students; Knowledge
Ramadan fasting and its attendant lifestyle changes induce changes in the circadian rhythm and in associated physiological and metabolic functions. Previous studies that have assessed psychomotor performance during Ramadan fasting have reported conflicting results. Therefore, we designed this study to objectively assess the effects of intermittent fasting during and outside Ramadan (to control for lifestyle changes) on drowsiness, blink total duration and mean reaction time (MRT) test while controlling for potential confounders.
Eight healthy volunteers with a mean age of 25.3 ± 2.9 years and a mean body mass index (BMI) of 23.4 ± 3.2 kg/m2 reported to the sleep laboratory on four occasions for polysomnography (PSG) and drowsiness and psychomotor assessments as follows: 1) adaptation; 2) 4 weeks before Ramadan while performing the Islamic fasting for 1 week (baseline fasting) (BLF); 3) 1 week before Ramadan (non-fasting baseline) (BL); and 4) during the second week of Ramadan while fasting (Ramadan). OPTALERT™ was used to objectively assess daytime drowsiness using the Johns Drowsiness Scale (JDS), and blink total duration and a visual reaction time test were used to assess MRT.
Rapid eye movement (REM) sleep percentage was significantly lower at BLF (17.7 ± 8.1%) and at Ramadan (18.6 ± 10.7%) compared with BL (25.6 ± 4.8%) (p < 0.05). There were no significant differences between JDS scores and blink total duration during the two test periods in BL, BLF and Ramadan. There were no significant changes in MRT during BL, BLF and Ramadan.
Under controlled conditions of fixed light/dark exposure, caloric intake, sleep/wake schedule and sleep quality, the Islamic intermittent fasting has no impact on drowsiness and vigilance as measured by the JDS, total blink duration and MRT.
Ramadan; Fasting; REM sleep; Vigilance; Mean reaction time; Blink duration; Optalert; Johns Drowsiness Scale
Subepithelial fibrosis is one of the most critical structural changes affecting bronchial airway function during asthma. Eosinophils have been shown to contribute to the production of pro-fibrotic cytokines, TGF-β and IL-11, however, the mechanism regulating this process is not fully understood.
In this report, we investigated whether cytokines associated with inflammation during asthma may induce eosinophils to produce pro-fibrotic cytokines.
Eosinophils were isolated from peripheral blood of 10 asthmatics and 10 normal control subjects. Eosinophils were stimulated with Th1, Th2 and Th17 cytokines and the production of TGF-β and IL-11 was determined using real time PCR and ELISA assays.
The basal expression levels of eosinophil derived TGF-β and IL-11 cytokines were comparable between asthmatic and healthy individuals. Stimulating eosinophils with Th1 and Th2 cytokines did not induce expression of pro-fibrotic cytokines. However, stimulating eosinophils with Th17 cytokines resulted in the enhancement of TGF-β and IL-11 expression in asthmatic but not healthy individuals. This effect of IL-17 on eosinophils was dependent on p38 MAPK activation as inhibiting the phosphorylation of p38 MAPK, but not other kinases, inhibited IL-17 induced pro-fibrotic cytokine release.
Th17 cytokines might contribute to airway fibrosis during asthma by enhancing production of eosinophil derived pro-fibrotic cytokines. Preventing the release of pro-fibrotic cytokines by blocking the effect of Th17 cytokines on eosinophils may prove to be beneficial in controlling fibrosis for disorders with IL-17 driven inflammation such as allergic and autoimmune diseases.
Asthma; Eosinophils; Th17 cytokines; Pro-fibrotic cytokines; TGF-β; IL-11
Studies have shown that a large proportion of traffic accidents around the world are related to inadequate or disordered sleep. Recent surveys have linked driver fatigue to 16% to 20% of serious highway accidents in the UK, Australia, and Brazil. Fatigue as a result of sleep disorders (especially obstructive sleep apnea), excessive workload and lack of physical and mental rest, have been shown to be major contributing factors in motor vehicle accidents. A number of behavioral, physiological, and psychometric tests are being used increasingly to evaluate the impact of fatigue on driver performance. These include the oculography, polysomnography, actigraphy, the maintenance of wakefulness test, and others. Various strategies have been proposed for preventing or reducing the impact of fatigue on motor vehicle accidents. These have included: Educational programs emphasizing the importance of restorative sleep and the need for drivers to recognize the presence of fatigue symptoms, and to determine when to stop to sleep; The use of exercise to increase alertness and to promote restorative sleep; The use of substances or drugs to promote sleep or alertness (i.e. caffeine, modafinil, melatonin and others), as well as specific sleep disorders treatment; The use of CPAP therapy for reducing excessive sleepiness among drivers who have been diagnosed with obstructive sleep apnea. The evidence cited in this review justifies the call for all efforts to be undertaken that may increase awareness of inadequate sleep as a cause of traffic accidents. It is strongly recommended that, for the purpose of promoting highway safety and saving lives, all disorders that cause excessive sleepiness should be investigated and monitored.
Alertness; fatigue; rest; sleep; traffic accident
Inadequate gas conditioning during non-invasive ventilation (NIV) can impair the anatomy and function of nasal mucosa. The resulting symptoms may have a negative effect on patients' adherence to ventilatory treatment, especially for chronic use. Several parameters, mostly technical aspects of NIV, contribute to inefficient gas conditioning. Factors affecting airway humidity during NIV include inspiratory flow, inspiratory oxygen fraction, leaks, type of ventilator, interface used to deliver NIV, temperature and pressure of inhaled gas, and type of humidifier. The correct application of a humidification system may avoid the effects of NIV-induced drying of the airway. This brief review analyses the consequences of airway dryness in patients receiving NIV and the technical tools necessary to guarantee adequate gas conditioning during ventilatory treatment. Open questions remain about the timing of gas conditioning for acute or chronic settings, the choice and type of humidification device, the interaction between the humidifier and the underlying disease, and the effects of individual humidification systems on delivered humidity.
Ramadan fasting and its associated lifestyle changes have been linked to changes in sleep and daytime sleepiness. This study was designed to assess the effects of Ramadan fasting on patterns of sleep and daytime sleepiness.
The SenseWear Pro Armband™ was used to assess the duration and distribution of sleep in eight Muslim and eight non-Muslim volunteers during the last week of Shaaban [baseline (BL) and the first (R1) and second (R2) weeks of Ramadan (1430 H)]. OPTALERT™ was used to assess daytime drowsiness objectively using the John Drowsiness Scale (JDS) to assess sleepiness, and a visual reaction time test was used to assess mean reaction time (MRT).
The mean ages of Muslims and non-Muslims were 36.25 ± 4.46 and 34.75 ± 3.33 years, respectively. Although the start of work was delayed for Muslims from 0730 to 1000 hours, there was no change in working hours for non-Muslims. During Ramadan, bedtime and wake-up time were delayed, and there was a significant reduction in total sleep time for Muslims (5.91 ± 1.36 hours, 4.95 ± 1.46 hours, and 4.78 ± 1.36 hours during BL, R1, and R2, respectively, P < 0.001), but not for non-Muslims. JDS values in both Muslims and non-Muslims were normal at BL (1.70 ± 1.16 and 1.68 ± 1.07, respectively), and no changes occurred during Ramadan (R1 or R2), indicating no increase in daytime sleepiness. There were no significant changes in MRT during R1 and R2 from BL in either group.
Although the sleep cycle of the studied sample shifted during Ramadan among fast observers, there was no objective evidence for increased sleepiness during fasting.
Ramadan; fasting; sleep; sleepiness; vigilance
The professional content of sleep medicine has grown significantly over the past few decades, warranting the recognition of sleep medicine as an independent specialty. Because the practice of sleep medicine has expanded in Saudi Arabia over the past few years, a national regulation system to license and ascertain the competence of sleep medicine physicians and technologists has become essential. Recently, the Saudi Commission for Health Specialties formed the National Committee for the Accreditation of Sleep Medicine Practice and developed national accreditation criteria. This paper presents the newly approved Saudi accreditation criteria for sleep medicine physicians and technologists.
Accreditation; licensing; sleep medicine; sleep technology; technicians; technologists
We aimed to evaluate the validity of the BodyMedia's SenseWear™ Armband (BSA) device in estimating total sleep time (TST) in patients with obstructive sleep apnea (OSA).
Simultaneous overnight recordings of in-laboratory polysomnography (PSG) and BSA were performed on (1) 107 OSA patients (mean age of 45.2 ± 14.3 years, mean apnea hypopnea index of 43 ± 35.7/hr and (2) 30 controls matched with OSA patients for age and body mass index. An agreement analysis between the PSG and BSA scoring results was performed using the Bland and Altman method.
There was no significant difference in OSA patients between BSA and PSG with regard to TST, total wake time, and sleep efficiency. There was also no significant difference in the controls between BSA and PSG with regard to TST, total wake time, and sleep efficiency. Bland Altman plots showed strong agreement between TST, wake time, and sleep efficiency for both OSA and the controls. The intraclass correlation coefficients revealed perfect agreement between BSA and PSG in different levels of OSA severity and both genders.
The current data suggest that BSA is a reliable method for determining sleep in patients with OSA when compared against the gold standard test (PSG). BSA can be a useful tool in determining sleep in patients with OSA and can be combined with portable sleep studies to determine TST.
Actigraphy; armband; polysomnography; portable monitoring; sleep apnea; sleep duration; sleep-disordered breathing; type 4 sleep study
The relationship between the sleep/wake habits and the academic performance of medical students is insufficiently addressed in the literature. This study aimed to assess the relationship between sleep habits and sleep duration with academic performance in medical students.
This study was conducted between December 2009 and January 2010 at the College of Medicine, King Saud University, and included a systematic random sample of healthy medical students in the first (L1), second (L2) and third (L3) academic levels. A self-administered questionnaire was distributed to assess demographics, sleep/wake schedule, sleep habits, and sleep duration. Daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS). School performance was stratified as “excellent” (GPA ≥3.75/5) or “average” (GPA <3.75/5).
The final analysis included 410 students (males: 67%). One hundred fifteen students (28%) had “excellent” performance, and 295 students (72%) had “average” performance. The “average” group had a higher ESS score and a higher percentage of students who felt sleepy during class. In contrast, the “excellent” group had an earlier bedtime and increased TST during weekdays. Subjective feeling of obtaining sufficient sleep and non-smoking were the only independent predictors of “excellent” performance.
Decreased nocturnal sleep time, late bedtimes during weekdays and weekends and increased daytime sleepiness are negatively associated with academic performance in medical students.
Sleep; Sleep duration; Medical students; Academic performance; School
Sleep has preoccupied and fascinated many civilizations since the dawn of mankind. Here, we critically review the various elements pertaining to sleep in the context of early Islamic religion and culture. The many principles of sleep hygiene, wellbeing and health associated with adequate sleep, and the understanding of sleep as a dynamic state are all apparent from such explorative process of Islamic tradition.
sleep; Islam; Qur’an; fasting; Hadith; Ramadan
Asthma is a chronic inflammatory disorder of the lung airways that is associated with airway remodeling and hyperresponsiveness. Its is well documented that the smooth muscle mass in asthmatic airways is increased due to hypertrophy and hyperplasia of the ASM cells. Moreover, eosinophils have been proposed in different studies to play a major role in airway remodeling. Here, we hypothesized that eosinophils modulate the airways through enhancing ASM cell proliferation. The aim of this study is to examine the effect of eosinophils on ASM cell proliferation using eosinophils isolated from asthmatic and normal control subjects.
Eosinophils were isolated from peripheral blood of 6 mild asthmatics and 6 normal control subjects. ASM cells were incubated with eosinophils or eosinophil membranes and ASM proliferation was estimated using thymidine incorporation. The mRNA expression of extracellular matrix (ECM) in ASM cells was measured using quantitative real-time PCR. The effect of eosinophil-derived proliferative cytokines on ASM cells was determined using neutralizing antibodies. The role of eosinophil derived Cysteinyl Leukotrienes in enhancing ASM was also investigated.
Co-culture with eosinophils significantly increased ASM cell proliferation. However, there was no significant difference in ASM proliferation following incubation with eosinophils from asthmatic versus normal control subjects. Co-culture with eosinophil membranes had no effect on ASM proliferation. Moreover, there was no significant change in the mRNA expression of ECM proteins in ASM cells following co-culture with eosinophils when compared with medium alone. Interestingly, blocking the activity of cysteinyl Leukotries using antagonists inhibited eosinophil-derived ASM proliferation.
Eosinophils enhances the proliferation of ASM cells. This role of eosinophil does not seem to depend on ASM derived ECM proteins nor on Eosinophil derived TGF-β or TNF-α. Eosinophil seems to induce ASM proliferation via the secretion of Cysteinyl Leukotrienes.
Muslims are required to wake up early to pray (Fajr) at dawn (approximately one and one-half hours before sunrise). Some Muslims wake up to pray Fajr and then sleep until it is time to work (split sleep), whereas others sleep continuously (consolidated sleep) until work time and pray Fajr upon awakening.
To objectively assess sleep architecture and daytime sleepiness in consolidated and split sleep due to the Fajr prayer.
SETTING AND DESIGN:
A cross-sectional, single-center observational study in eight healthy male subjects with a mean age of 32.0 ± 2.4 years.
The participants spent three nights in the Sleep Disorders Center (SDC) at King Khalid University Hospital, where they participated in the study, which included (1) a medical checkup and an adaptation night, (2) a consolidated sleep night, and (3) a split-sleep night. Polysomnography (PSG) was conducted in the SDC following the standard protocol. Participants went to bed at 11:30 PM and woke up at 7:00 AM in the consolidated sleep protocol. In the split-sleep protocol, participants went to bed at 11:30 PM, woke up at 3:30 AM for 45 minutes, went back to bed at 4:15 AM, and finally woke up at 7:45 AM. PSG was followed by a multiple sleep latency test to assess the daytime sleepiness of the participants.
There were no differences in sleep efficiency, the distribution of sleep stages, or daytime sleepiness between the two protocols.
No differences were detected in sleep architecture or daytime sleepiness in the consolidated and split-sleep schedules when the total sleep duration was maintained.
Consolidated sleep; daytime sleepiness; Fajr prayer; sleep architecture; split sleep
Sleep medicine is a relatively new scientific specialty. Sleep is an important topic in Islamic literature, and the Quran and Hadith discuss types of sleep, the importance of sleep, and good sleep practices. Islam considers sleep as one of the signs of the greatness of Allνh (God) and encourages followers to explore this important sign. The Quran describes different types of sleep, and these correspond with sleep stages identified by modern science. The Quran discusses the beneficial effects of sleep and emphasizes the importance of maintaining a pattern of light and darkness. A mid-day nap is an important practice for Muslims, and the Prophet Muhammad peace be upon him (pbuh) promoted naps as beneficial. In accordance with the practice and instructions of Muhammad (pbuh), Muslims have certain sleep habits and these sleep habits correspond to some of the sleep hygiene rules identified by modern science. Details during sleep include sleep position, like encouraging sleep on the right side and discouraging sleep in the prone position. Dream interpretation is an established science in the Islamic literature and Islamic scholars have made significant contributions to theories of dream interpretation. We suggest that sleep scientists examine religious literature in general and Islamic literature in particular, to understand the views, behaviors, and practices of ancient people about the sleep and sleep disorders. Such studies may help to answer some unresolved questions in sleep science or lead to new areas of inquiry.
Circadian rhythm; dreams; Islam; Quran; sleep
There is no simple and practical way to monitor sleep patterns in patients in acute care units. We designed this study to assess sleep patterns, energy expenditure and circadian rhythms of patients’ skin temperature in the coronary care unit (CCU) utilizing a new portable device.
The SenseWear Armband (SWA) was used to record sleep duration, distribution over 24 hr, energy expenditure and the circadian rhythms of skin temperature in 46 patients with acute coronary syndrome (ACS) for the first 24 hr in the CCU and upon transfer to the ward. An advanced analysis was used to extract and compare data associated with the above variables in the two settings.
Patients in the CCU had a reduced night’s sleep duration (5.6±2.2 hr) with more frequent and significantly shorter night sessions (p=0.015) than patients in the ward. Energy expenditure and METs (metabolic equivalents of a task) were significantly lower in the CCU than in the ward. However, the midline-estimating statistic of rhythm (MESOR) and acrophase for skin temperature did not exhibit any significant difference between the two settings.
Patients with ACS have sleep fragmentation and shorter nocturnal sleep duration in the CCU compared to the ward. On the other hand, there was no difference in the circadian rhythms of skin temperature between patients in the CCU and the general wards.
acute coronary syndrome; acute myocardial infarction; circadian rhythm; sleep; energy expenditure; temperature
BACKGROUND AND OBJECTIVES:
There are no published data on the chronotypes of young Saudi adults. This study assessed the distribution of chronotypes in college-aged Saudis.
DESIGN AND SETTING:
Cross-sectional survey of college students
PATIENTS AND METHODS:
A validated abridged version of the original Horne and Ostberg morningness-eveningness questionnaire (MEQr) was used to assess the chronotype of 759 subjects.
Of 540 (71.1%) males and 219 (28.9%) females participated in this study ( age range, 18-32 years), 138 (18.2%) were “morning-types” 417 (54.9%) were “neither-types” and 204 (26.9%) were “evening-types”. There was no significant gender difference in MEQr typology. In Saudis, particularly males, the frequency of morning typology was somewhat higher than that reported for individuals in similar age groups in some Western countries.
Most Saudi college students had no preference for morningness or eveningness and were classified as “intermediate-type”. Morningness appears to be slightly more common in Saudis, especially males, than in individuals of some Western societies.
ApneaLink™ (AL) is a single-channel type-4 device that measures airflow. A limited number of studies have assessed AL’s usefulness in diagnosing obstructive sleep apnea (OSA) using automated scoring alone. This study was conducted to assess the sensitivity and specificity of AL in a selected group of people with clinical suspicion of OSA, using both automatic and manual scoring and comparing the results with those obtained for polysomnography (PSG).
Simultaneous overnight recordings of in-laboratory PSG and AL were performed for 95 patients (mean age 46.3±12.6 yr) with a high clinical suspicion of OSA. PSG was scored manually according to the American Academy of Sleep Medicine (AASM) guidelines. AL data were analyzed automatically using a manufacturer-provided computerized algorithm. Manual scoring of the AL flow signal followed the AASM guidelines for reduction in flow.
The mean apnea hypopneas index (AHI) for PSG was 34.1±32.4/hr. The AL Auto-AHI was 20.1±25.2/h, and the AL Manual-AHI was 39.5±30.4/h. The Pearson correlation coefficients were r=0.883 between PSG-AHI and AL Auto-AHI, and r=0.966 between PSG-AHI and AL Manual-AHI. At AHIs of 5, 10, 15, and 30, the AL Auto sensitivity/specificity was 0.79/0.68, 0.70/0.89, 0.64/0.94 and 0.63/0.98, and the AL Manual sensitivity/specificity was 1.00/0.43, 1.00/0.56, 0.98/0.58 and 1.00/0.80.
Combining auto and manual scoring of data (automatic scoring followed by manual scoring) recorded by single-channel ApneaLink™ provides good diagnostic agreement with conventional PSG recordings.
sleep-disordered breathing; sleep apnea; ApneaLink; polysomnography; type 4 sleep study; portable monitoring
Sleep medicine is a relatively new specialty in the medical community. The practice of sleep medicine in Saudi Arabia (KSA) began in the mid to late nineties. Since its inception, the specialty has grown, and the number of specialists has increased. Nevertheless, sleep medicine is still underdeveloped in the KSA, particularly in the areas of clinical service, education, training and research. Based on available data, it appears that sleep disorders are prevalent among Saudis, and the demand for sleep medicine service is expected to rise significantly in the near future. A number of obstacles have been defined that hinder the progress of the specialty, including a lack of trained technicians, specialists and funding. Awareness about sleep disorders and their serious consequences is low among health care workers, health care authorities, insurance companies and the general public. A major challenge for the future is penetrating the educational system at all levels to demonstrate the high prevalence and serious consequences of sleep disorders. To attain adequate numbers of staff and facilities, the education and training of health care professionals at the level of sleep medicine specialists and sleep technologists is another important challenge that faces the specialty. This review discusses the current position of sleep medicine as a specialty in the KSA and the expected challenges of the future. In addition, it will guide clinicians interested in setting up new sleep medicine services in the KSA or other developing countries through the potential obstacles that may face them in this endeavor.
Developing countries; Saudi Arabia; sleep; sleep centers; sleep disordered breathing; sleep laboratories; sleep medicine
Over the last three to four decades, it has been observed that the average total hours of sleep have decreased to less than seven hours per person per night. Concomitantly, global figures relating to obesity and diabetes mellitus have increased in an alarming fashion in adults and children, and it has been hypothesized that neuro-hormonal changes accompanying this behavioral sleep deprivation may lead to insulin resistance and, subsequently, to diabetes mellitus. Sleep deprivation has been associated with multiple physiological changes, including increased cortisol and ghrelin levels, decreased leptin levels and impaired glucose metabolism. Experimental studies have also shown an increase in inflammatory and pro-inflammatory markers, which are indicators of body stress, under sleep deprivation. This review elaborates further on this hypothesis, exploring the molecular basis for the link between both entities and the underlying pathophysiology that results in insulin resistance and diabetes mellitus. We review the results of experimental and epidemiological studies, specifically examining the relationship between sleep duration and the immune and endocrine systems.
Sleep deprivation; obesity; glucose intolerance; insulin resistance; diabetes mellitus; ghrelin; leptin.
Obesity is becoming a major medical concern in several parts of the world, with huge economic impacts on health- care systems, resulting mainly from increased cardiovascular risks. At the same time, obesity leads to a number of sleep-disordered breathing patterns like obstructive sleep apnea and obesity hypoventilation syndrome (OHS), leading to increased morbidity and mortality with reduced quality of life. OHS is distinct from other sleep- related breathing disorders although overlap may exist. OHS patients may have obstructive sleep apnea/hypopnea with hypercapnia and sleep hypoventilation, or an isolated sleep hypoventilation. Despite its major impact on health, this disorder is under-recognized and under-diagnosed. Available management options include aggressive weight reduction, oxygen therapy and using positive airway pressure techniques. In this review, we will go over the epidemiology, pathophysiology, presentation and diagnosis and management of OHS.
Obesity hypoventilation syndrome; positive pressure ventilation; sleep-disordered breathing