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1.  Dimensionality of the Pittsburgh Sleep Quality Index in the young collegiate adults 
SpringerPlus  2016;5(1):1550.
To explore and validate the factor structure of the Pittsburgh Sleep Quality Index (PSQI) in young collegiate adults.
Six hundred university students were initially contacted and invited to participate in a survey of their sleep experience and history. Of this preliminary sample 418 of the students (age = 20.92 ± 1.81 years, BMI = 23.30 ± 2.57 kg/m2) fulfilled the screening criteria and ultimately completed the Pittsburgh Sleep Quality Index (PSQI), a self-report survey of respondents’ sleep habits and sleep quality. The students were enrolled in various undergraduate and postgraduate programs at Jamia Millia Islamia, New Delhi, India. Exploratory factor analysis (EFA) investigated the latent factor structure of the scale. Confirmatory factor analysis evaluated both of the models found by EFA.
The Kaiser’s criteria, the Scree test, and the cumulative variance rule revealed that a 2-factor model accounted for most of the variability in the data. However, a follow up Parallel Analysis found a 1-factor model. The high correlation coefficient (r = 0.91) between the two factors of the 2-factor model and almost similar values of the fit indices supports the inference that the PSQI is a unidimensional scale.
The findings validate the 1-factor model of the PSQI in young collegiate adults.
PMCID: PMC5021660  PMID: 27652123
Confirmatory factor analysis; Exploratory factor analysis; Collegiate, young adults; Model fit; Students
2.  Polysomnographic correlates of inflammatory complement components in young healthy males 
Sleep Science  2016;9(2):123-127.
A growing body of evidence has delineated the predominant role of humoral mediators of inflammation in linking sleep with immunity. Nonetheless, characterization of the relationship between complement components with inflammatory functions and objective sleep measures has not been performed. In this study we investigated the relationships between objective measures of sleep and complement components with inflammatory functions. Thirty-six healthy male university students (age, 23.94±4.23 years; BMI, 23.44±2.67 kg/m2) completed the study. An RMS Quest 32 polysomnograph (PSG) was used for sleep recording. Non-fasting blood was collected before subjects went to bed on the second night in the sleep laboratory to estimate complement component 3 (C-3), complement component 4 (C-4), complement factor-H (Factor-H), C1-inhibitor (C1INH), complement factor I (CFI) and other inflammatory mediators, such as IL-6 and sICAM-1. Multiple linear regression analysis was used to assess the association between PSG sleep measures and inflammatory mediators. Higher values of C-3 and lower values of sICAM-1, C1INH, and CFI (adjusted model, R2=0.211, p<0.041) predicted longer sleep duration. Lower C-3 (adjusted model, R2=0.078, p<0.055) predicted higher N1 (%). Higher levels of C1INH and CFI and lower values of C-4 (model adjusted R2=0.269, p<0.008) predicted higher N3 (%). Higher C-3, higher C-4, lower IL-6, lower C1INH and lower CFI (model adjusted R2=0.296, p<0.007) predicted higher REM (%). Poor sleep measures were associated with increased levels of pro-inflammatory complement components and decreased anti-inflammatory complement components.
PMCID: PMC5021955  PMID: 27656278
Sleep; Inflammation; Complement component; Inflammatory mediators; Cytokine; Polysomnography
3.  Spontaneous K-Complex Density in Slow-Wave Sleep 
PLoS ONE  2016;11(3):e0150929.
To study spontaneous K-complex (KC) densities during slow-wave sleep. The secondary objective was to estimate intra-non-rapid eye movement (NREM) sleep differences in KC density.
Materials and Methods
It is a retrospective study using EEG data included in polysomnographic records from the archive at the sleep research laboratory of the Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia, India. The EEG records of 4459 minutes were used. The study presents a manual identification investigation of KCs in 17 healthy young adult male volunteers (age = 23.82±3.40 years and BMI = 23.42±4.18 kg/m2).
N3 had a higher KC density than N2 (Z = -2.485, p = 0.013) for all of the probes taken together. Four EEG probes had a higher probe-specific KC density during N3. The inter-probe KC density differed significantly during N2 (χ2 = 67.91, p < .001), N3 (χ2 = 70.62, p < .001) and NREM (χ2 = 68.50, p < .001). The percent distribution of KC decreased uniformly with sleep cycles.
The inter-probe differences during N3 establish the fronto-central dominance of the KC density regardless of sleep stage. This finding supports one local theory of KC generation. The significantly higher KC density during N3 may imply that the neuro-anatomical origin of slow-wave activity and KC is the same. This temporal alignment with slow-wave activity supports the sleep-promoting function of the KC.
PMCID: PMC4786157  PMID: 26963714
4.  The effect of Ramadan intermittent fasting on lipid peroxidation in healthy young men while controlling for diet and sleep: A pilot study 
Annals of Thoracic Medicine  2016;11(1):43-48.
We hypothesized that if we control for lifestyle changes during Ramadan, Ramadan Islamic intermittent fasting (IF) reduces oxidative stress. This study was conducted to examine the effect of Islamic IF during and outside of Ramadan on the circadian changes in lipid peroxidation marker malondialdehyde (MDA) during and outside while controlling for potential confounders.
Serum MDA concentration was measured in eight healthy male volunteers at baseline (BL), after fasting for 1 week before Ramadan (BL fasting), and during Ramadan. Blood samples were drawn at 22:00, 02:00, 04:00, 06:00, and 11:00. The participants were admitted to the sleep laboratory and monitored for 24 h on the day of the measurements. In the laboratory, each participant received meals of fixed compositions and caloric contents based on their ideal body weights. Light exposure, physical activity, and total sleep duration were uniformly maintained during the three study periods.
The participants had a mean age of 26.6 ± 4.9 years and a mean body mass index of 23.7 ± 3.5 kg/m2. No significant changes were observed in MDA levels and blood glucose during BL, BL fasting, or Ramadan.
In this pilot study, under conditions of fixed sleep-wake schedules and caloric intake, Ramadan IF does not alter serum MDA levels in healthy subjects. Larger studies are needed to confirm these findings.
PMCID: PMC4748614  PMID: 26933456
Caloric restriction; circadian; intermittent fasting; malondialdehyde; oxidative stress; Ramadan; sleep
5.  The success rate of split-night polysomnography and its impact on continuous positive airway pressure compliance 
Annals of Thoracic Medicine  2015;10(4):274-278.
With the increased volume of referrals of patients with obstructive sleep apnea (OSA) for sleep studies, there is a great need for alternatives of the standard two-night polysomnography (PSG) like split-night PSG. Therefore, we conducted this study to determine the success rate of continuous positive airway pressure (CPAP) titration during split-night PSG, and to determine the predictors of titration success and the impact on subsequent CPAP compliance in Saudi patients with OSA.
This is a prospective cohort study that included consecutive patients who were diagnosed with OSA and underwent a split-night PSG (n = 454). A subgroup of patients who used CPAP therapy, agreed to come for follow-up after 4 and 10 months (n = 130). This subgroup was compared with a matched group of OSA patients who underwent a two-night sleep study protocol (n = 80).
The study group had a mean age of 48.7 ± 13.3 years, body mass index (BMI) of 37.5 ± 10.1 kg/m2 and apnea hypopnea index of 58.4 ± 35.0 events/h. Successful CPAP titration was achieved in 350 (77%) patients. In a full adjusted model, “BMI >35 kg/m2” and “known cardiac disease” remained significant predictors of a lower success rate of CPAP titration. After 10 months, 88% of the patients in the split-night protocol met the set criteria for good compliance versus 85% in the two-night protocol.
Split-night protocol is an effective protocol for diagnosing OSA and titrating CPAP. CPAP compliance rate showed no difference between the split-night and the two-night protocols.
PMCID: PMC4652294  PMID: 26664566
Continuous positive airway pressure; obstructive sleep apnea; polysomnography; split-night sleep study
6.  Long-term compliance with continuous positive airway pressure in Saudi patients with obstructive sleep apnea 
Saudi Medical Journal  2015;36(8):911-919.
To evaluate continuous positive airway pressure (CPAP) compliance and define predictors of CPAP compliance among Saudi patients with obstructive sleep apnea (OSA) after applying an educational program.
This prospective cohort study included consecutive patients diagnosed to have OSA based on polysomnography between January 2012 and January 2014 in King Saud University, Riyadh, Kingdom of Saudi Arabia. All patients had educational sessions on OSA and CPAP therapy before sleep study, and formal hands-on training on CPAP machines on day one, day 7, and day 14 after diagnosis. The follow-up in the clinic was carried out at one, 4, and 10 months after initiating CPAP therapy. Continuous positive airway pressure compliance was assessed objectively. Logistic regression model was used to assess the predictors of CPAP adherence.
The study comprised 156 patients with a mean age of 51.9±12.1 years, body mass index of 38.4±10.6 kg/m2, and apnea hypopnea index of 63.7±39.3 events/hour. All patients were using CPAP at month one, 89.7% at month 4, and 83% at month 10. The persistence of CPAP-related side effects and comorbid bronchial asthma remained as independent predictors of CPAP compliance at the end of the study.
With intensive education, support, and close monitoring, more than 80% of Saudi patients with OSA continued to use CPAP after 10 months of initiating CPAP therapy.
PMCID: PMC4549586  PMID: 26219440
7.  The Validity and Reliability of an Arabic Version of the STOP-Bang Questionnaire for Identifying Obstructive Sleep Apnea 
Obstructive sleep apnea (OSA) is a common, serious, under-recognized and under-diagnosed medical disorder. Polysomnography (PSG) is the gold standard diagnostic test for OSA; however, the cost of testing and the shortage of sleep disorders laboratories limit access to this tool. Therefore, there is a need for a simple and reliable diagnostic tool to screen patients at risk of OSA.
This study was conducted to evaluate the validity and reliability of an Arabic version of the STOP-Bang questionnaire (SBQ) as a screening tool for OSA.
This study was conducted in three steps, as follows: Step 1: the SBQ was translated from English to Arabic (examining both forward and backward translations); Step 2: the test-retest reliability of the questionnaire was investigated; and Step 3: the questionnaire was validated against PSG data prospectively on 100 patients attending a sleep disorders clinic who were subjected to a full-night PSG study after completing the translated version of the SBQ. The validity of the test was tested against the apnea-hypopnea index (AHI).
The study group had a mean age of 46.6 ± 14.0 years and a mean AHI of 50.0 ± 37.0/hour. The study demonstrated a high degree of internal consistency and stability over time for the translated SBQ. The Cronbach’s alpha coefficient for the 8-item tool was 0.7. Validation of the SBQ against the AHI at a cut-off of 5 revealed a sensitivity of 98% and positive and negative predictive values of 86% and 67%, respectively.
The Arabic version of the SBQ is an easy-to-administer, simple, reliable and valid tool for the identification of OSA in the sleep disorders clinic setting.
PMCID: PMC4378065  PMID: 25834656
Apnea-hypopnea index; STOP-Bang questionnaire; obstructive sleep apnea; validity; reliability; screening; sleepiness
8.  Prevalence, clinical characteristics, and predictors of obesity hypoventilation syndrome in a large sample of Saudi patients with obstructive sleep apnea 
Saudi Medical Journal  2015;36(2):181-189.
To assess the prevalence, clinical characteristics, and predictors of obesity hypoventilation syndrome (OHS) in a large sample of Saudi patients with obstructive sleep apnea (OSA).
This prospective observational study consisted of 1693 patients who were diagnosed to have sleep-disordered breathing using type I attended polysomnography (PSG) between January 2002 and December 2012 in the University Sleep Disorders Center (USDC) at King Saud University Hospital, Riyadh, Kingdom of Saudi Arabia.
Out of 1693 OSA patients, OHS was identified in 144 (8.5%) (women 66.7%). Compared with the pure OSA patients, the OHS patients were significantly older (57.4±13.4 years versus 46.8±13.7 years), had a higher body mass index (44.6±10.8 versus 35.7±9.2 kg/m2), a higher daytime partial pressure of carbon dioxide (PaCO2) (56.5±12.7 versus 41.6±6.7 mmHg), a longer duration of nocturnal oxygen saturation (nSaO2) <90% (71.0±34.3 versus 10.5±20.5 minutes), and a higher apnea hypopnea index (68.2±47.1 versus 46.5±34.1 events/hour). A multivariate logistic regression analysis showed that serum bicarbonate (odds ratio [OR]=1.17, p=0.0001, confidence interval [CI]=1.10-1.25), and duration of nSaO2 <90% (OR=1.05, p=0.0001, CI=1.04-1.06) were predictors of OHS.
Obesity hypoventilation syndrome is common among Saudi OSA patients referred to the Sleep Disorders Center. Serum bicarbonate and duration of nSaO2 <90% are independent predictors of OHS among patients with OSA.
PMCID: PMC4375695  PMID: 25719582
9.  IL-17 Enhances Chemotaxis of Primary Human B Cells during Asthma 
PLoS ONE  2014;9(12):e114604.
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.
PMCID: PMC4262428  PMID: 25494178
10.  Association of Per3 length polymorphism with bipolar I disorder and schizophrenia 
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.
PMCID: PMC4267513  PMID: 25525361
circadian rhythms; clock genes; Per3 polymorphism; bipolar disorder; schizophrenia
11.  Diurnal Intermittent Fasting during Ramadan: The Effects on Leptin and Ghrelin Levels 
PLoS ONE  2014;9(3):e92214.
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.
PMCID: PMC3956913  PMID: 24637892
12.  Sleep medicine services in Saudi Arabia: The 2013 national survey 
Annals of Thoracic Medicine  2014;9(1):45-47.
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.
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.
PMCID: PMC3912688  PMID: 24551019
Polysomnography; quantitative assessment; sleep disorders center; sleep medicine service; sleep technologists
13.  Sleep medicine education and knowledge among medical students in selected Saudi Medical Schools 
BMC Medical Education  2013;13:133.
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.
PMCID: PMC3849688  PMID: 24070217
Sleep medicine; Education; ASKME survey; Medical schools; Medical students; Knowledge
14.  Objective assessment of drowsiness and reaction time during intermittent Ramadan fasting in young men: a case-crossover study 
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.
PMCID: PMC3751553  PMID: 23937904
Ramadan; Fasting; REM sleep; Vigilance; Mean reaction time; Blink duration; Optalert; Johns Drowsiness Scale
15.  Th17 cytokines induce pro-fibrotic cytokines release from human eosinophils 
Respiratory Research  2013;14(1):34.
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.
PMCID: PMC3602055  PMID: 23496774
Asthma; Eosinophils; Th17 cytokines; Pro-fibrotic cytokines; TGF-β; IL-11
16.  Sleep Disorders as a Cause of Motor Vehicle Collisions 
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.
PMCID: PMC3634162  PMID: 23626880
Alertness; fatigue; rest; sleep; traffic accident
17.  Clinical review: Humidifiers during non-invasive ventilation - key topics and practical implications 
Critical Care  2012;16(1):203.
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.
PMCID: PMC3396215  PMID: 22316078
18.  The effects of Ramadan fasting on sleep patterns and daytime sleepiness: An objective assessment 
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.
PMCID: PMC3724373  PMID: 23914215
Ramadan; fasting; sleep; sleepiness; vigilance
19.  Saudi regulations for the accreditation of sleep medicine physicians and technologists 
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.
PMCID: PMC3573555  PMID: 23440260
Accreditation; licensing; sleep medicine; sleep technology; technicians; technologists
20.  Sleep estimation using BodyMedia's SenseWear™ armband in patients with obstructive sleep apnea 
Annals of Thoracic Medicine  2013;8(1):53-57.
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.
PMCID: PMC3573559  PMID: 23440703
Actigraphy; armband; polysomnography; portable monitoring; sleep apnea; sleep duration; sleep-disordered breathing; type 4 sleep study
21.  The relationship between sleep and wake habits and academic performance in medical students: a cross-sectional study 
BMC Medical Education  2012;12:61.
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.
PMCID: PMC3419622  PMID: 22853649
Sleep; Sleep duration; Medical students; Academic performance; School
22.  Qur’anic insights into sleep 
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.
PMCID: PMC3630974  PMID: 23620681
sleep; Islam; Qur’an; fasting; Hadith; Ramadan
23.  Sleep medicine: Present and future 
Annals of Thoracic Medicine  2012;7(3):113-114.
PMCID: PMC3425040  PMID: 22924066
24.  127 Eosinophils Enhance Airway Smooth Muscle Cell Proliferation Via the Release of Cysteinyl Leukotrines 
The World Allergy Organization Journal  2012;5(Suppl 2):S59-S60.
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.
PMCID: PMC3513122
25.  Sleep architecture of consolidated and split sleep due to the dawn (Fajr) prayer among Muslims and its impact on daytime sleepiness 
Annals of Thoracic Medicine  2012;7(1):36-41.
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.
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.
PMCID: PMC3277040  PMID: 22347349
Consolidated sleep; daytime sleepiness; Fajr prayer; sleep architecture; split sleep

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