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Sleep patterns and quality in Omani adults
Abstracts/Sleep Medicine 16 (2015) S2–S199
Materials and methods: Here, we investigate the role of GABA neurons from the lateral hypothalamus (LH) on sleep–wake states. We targeted the expression of channelrhodopsin-2 opsin (ChETA) to the LH-GABA cells of VGAT::Cre mice. To study the anatomical connectivity between the LH and the TRN, we used both anterograde and retrograde labeling. In vitro patch clamp recordings confirmed the functionality of this connectivity by optically stimulation (5 ms pulses of 473 nm blue light) to elicit postsynaptic responses in TRN cells. Pharmacology to block GABAA receptor was used to confirm the GABAergic nature of the elicited photocurrents. EEG/EMG recordings were use to characterize sleep/wake changes in response to optogenetic stimulation. Optic fibers were implanted either in the LH or TRN of ChETA and control (YFP) mice. We used semichronic (semi-chronic (1–20 Hz during 10 s, every minute over 1 h) and stage-dependent optical stimulations to screen for effective frequencies that modulate architecture of the sleep– wake cycle. For the anesthesia experiment, level of anesthesia was determined by the lost of righting reflex and in the EEG recordings and the onset of bust suppression mode. Animals were stimulated for 5 s of continuous blue light bilaterally three times with 5 min intervals in between stimulations. Results: We identified anatomical connections between LH GABA neurons in other brain areas including locus coeruleus, septum, and reticular thalamic nucleus (TRN). Using a bilateral optical activation (1–20 Hz, 10 s every minute over 1 h), we showed that LHGABA cells at 20 Hz, but not 1 Hz, resulted in a twofold increase in wake duration. In addition, we activated LH-GABA cells at different sleep states on their transition to wake. We found that a single stimulation at 1–20 Hz, over 10 s induced a rapid switch from sleep to wakefulness (<2 s) during NREM and significantly increases wakefulness duration in ChETA compared with control animals. Interestingly, this is not observed when LH-GABA cells are activated during REM sleep. Further, we showed a functional connectivity in LH-RTN. Here, local optical activation in vitro of LH-GABA terminals in the TRN induced GABAA-mediated IPSCs in reticular neurons, as well as a desynchronization of cortico-thalamic loops and short latency NREM sleep-to-wake transitions in vivo. Further we observed that during stable anesthesized states, optical activation of LH-GABA terminals in the TRN, inhibiting the activity of TRN cells, causes cortical reactivation in animals expressing ChETA but not in controls. Conclusion: Collectively, these data suggest that GABA projections from the LH->TRN represents a direct arousal circuit to thalamic and cortical structures. Furthermore, our results suggest that activation of a subpopulation of LH-GABA neurons induces rapid wake from sleep, through inhibition of TRN cells and subsequent reactivation of thalamo-cortical loops. http://dx.doi.org/10.1016/j.sleep.2015.02.080
Sleep patterns and quality in Omani adults I. Juma College of Medicin In Squ, Oman
Introduction: Since the start of the industrial revolution, sleep pattern and quality have been continuously changing worldwide. This is associated with an emergence of sleep disorders and increased prevalence of cardiometabolic abnormalities. This part of the study aims to investigate the sleep patterns of Omani adults in relation to sleep quality. Materials and methods: This cross sectional study was ethically approved by the College of Medicine in Sultan Qaboos University in April 2014. Informed consent forms were obtained from subjects
S33
before study enrollment. Two thousand questionnaires were randomly distributed among Omani adults aged 18–65 years in Muscat region. Five hundred subjects (66.8% female and 33.2% male) who fulfilled the inclusion criteria were categorized into five age groups in years, 18–24, 25–34, 35–45, 46–54, and 55–65, based on Ministry of Health criteria. In addition to demographic data and sleep habits, sleep quality (SQ) and daytime sleepiness (DTS) were assessed using the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleep Scale (ESS) respectively. PSQI scores of 5 or less represented good sleep quality while scores more than 5 were considered as poor sleep quality. In relation to daytime sleepiness, subjects were divided into four categories as per ESS scores; zero score for normal subjects, 1–6 mild DTS, 7–9 moderate DTS, and ≥10 were defined as severe DTS. Subjects who slept less than 7 h were considered as short sleepers. Finally, data were collected, entered, tested for normality and analyzed using descriptive, univariate (χ2 test) and multivariate (Kruskal–Waills test) packages of SPSS version (21). Results: The predominant sleep patterns among Omanis were either polyphasic having more than two sleep periods per day (49.60%) or biphasic having two sleep periods (42.4%). The sleep patterns were not associated with gender (p = 0.888) or age (p = 0.06). However, there was an obvious trend between sleep patterns and age; younger and elderly groups expressed higher prevalence toward polyphasic pattern (54.81% and 68.00 % respectively). Night sleep duration was insignificant (p = 0.063) among all sleep patterns with an average of 6.18 h. This was confirmed with elevated prevalence of short night sleepers (67.60%), which was dominant among biphasic and polyphasic sleepers. This was in contrast regarding the average sleep duration within 24 h. (p = 0.000). Polyphasic sleepers had longer sleep duration with an average of 7.96 h that was significantly attributed to long siesta (73.27%). Daytime sleepiness was significantly different across sleep patterns (p = 0.000) with an average of 8.97. Monophasic and biphasic patterns were associated with moderate DTS (6.74 and 8.60) (20.60%), whereas polyphasic pattern was linked to severe DTS (9.66) (52.80%). Furthermore, 47% were poor sleepers with an average score of 5.50. This was insignificantly different across all sleep patterns (p = 0.107) although the PSQI average score for polyphasic pattern (5.65) indicated poor sleep quality. Conclusion: Sleep pattern among Omanis is directed toward polyphasic, which is associated with short night duration, long siesta, and severe DTS, hence poor sleep hygiene and quality. Further studies will be conducted soon to associate between this sleep pattern of Omanis and cardio-metabolic risk using metabolic biomarkers. Acknowledgements: This work was supported by the College of Medicine in Sultan Qaboos University. Deep gratitude is extended to the committee members; Professor Mohammed Osman Hassan, Dr Mohammed Al-Abri, Dr Fahad Al-Zidjali, Dr Deepali, and Dr Gangoli, all volunteers, clinical technicians and my family members for their input, support and guidance. http://dx.doi.org/10.1016/j.sleep.2015.02.081
Impaired postural stability in sleep disordered breathing patients F. Degache 1, Y. Goy 2, S. Vat 3, J. Haba Rubio 3, O. Contal 1, R. Heinzer 3 1 University of Health Sciences, Health Research Unit, University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland 2 Institute of Sports Sciences, Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland 3 Center for Investigation and Research in Sleep (CIRS), University Hospital of Lausanne (CHUV), Switzerland
Materials and methods: Here, we investigate the role of GABA neurons from the lateral hypothalamus (LH) on sleep–wake states. We targeted the expression of channelrhodopsin-2 opsin (ChETA) to the LH-GABA cells of VGAT::Cre mice. To study the anatomical connectivity between the LH and the TRN, we used both anterograde and retrograde labeling. In vitro patch clamp recordings confirmed the functionality of this connectivity by optically stimulation (5 ms pulses of 473 nm blue light) to elicit postsynaptic responses in TRN cells. Pharmacology to block GABAA receptor was used to confirm the GABAergic nature of the elicited photocurrents. EEG/EMG recordings were use to characterize sleep/wake changes in response to optogenetic stimulation. Optic fibers were implanted either in the LH or TRN of ChETA and control (YFP) mice. We used semichronic (semi-chronic (1–20 Hz during 10 s, every minute over 1 h) and stage-dependent optical stimulations to screen for effective frequencies that modulate architecture of the sleep– wake cycle. For the anesthesia experiment, level of anesthesia was determined by the lost of righting reflex and in the EEG recordings and the onset of bust suppression mode. Animals were stimulated for 5 s of continuous blue light bilaterally three times with 5 min intervals in between stimulations. Results: We identified anatomical connections between LH GABA neurons in other brain areas including locus coeruleus, septum, and reticular thalamic nucleus (TRN). Using a bilateral optical activation (1–20 Hz, 10 s every minute over 1 h), we showed that LHGABA cells at 20 Hz, but not 1 Hz, resulted in a twofold increase in wake duration. In addition, we activated LH-GABA cells at different sleep states on their transition to wake. We found that a single stimulation at 1–20 Hz, over 10 s induced a rapid switch from sleep to wakefulness (<2 s) during NREM and significantly increases wakefulness duration in ChETA compared with control animals. Interestingly, this is not observed when LH-GABA cells are activated during REM sleep. Further, we showed a functional connectivity in LH-RTN. Here, local optical activation in vitro of LH-GABA terminals in the TRN induced GABAA-mediated IPSCs in reticular neurons, as well as a desynchronization of cortico-thalamic loops and short latency NREM sleep-to-wake transitions in vivo. Further we observed that during stable anesthesized states, optical activation of LH-GABA terminals in the TRN, inhibiting the activity of TRN cells, causes cortical reactivation in animals expressing ChETA but not in controls. Conclusion: Collectively, these data suggest that GABA projections from the LH->TRN represents a direct arousal circuit to thalamic and cortical structures. Furthermore, our results suggest that activation of a subpopulation of LH-GABA neurons induces rapid wake from sleep, through inhibition of TRN cells and subsequent reactivation of thalamo-cortical loops. http://dx.doi.org/10.1016/j.sleep.2015.02.080
Sleep patterns and quality in Omani adults I. Juma College of Medicin In Squ, Oman
Introduction: Since the start of the industrial revolution, sleep pattern and quality have been continuously changing worldwide. This is associated with an emergence of sleep disorders and increased prevalence of cardiometabolic abnormalities. This part of the study aims to investigate the sleep patterns of Omani adults in relation to sleep quality. Materials and methods: This cross sectional study was ethically approved by the College of Medicine in Sultan Qaboos University in April 2014. Informed consent forms were obtained from subjects
S33
before study enrollment. Two thousand questionnaires were randomly distributed among Omani adults aged 18–65 years in Muscat region. Five hundred subjects (66.8% female and 33.2% male) who fulfilled the inclusion criteria were categorized into five age groups in years, 18–24, 25–34, 35–45, 46–54, and 55–65, based on Ministry of Health criteria. In addition to demographic data and sleep habits, sleep quality (SQ) and daytime sleepiness (DTS) were assessed using the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleep Scale (ESS) respectively. PSQI scores of 5 or less represented good sleep quality while scores more than 5 were considered as poor sleep quality. In relation to daytime sleepiness, subjects were divided into four categories as per ESS scores; zero score for normal subjects, 1–6 mild DTS, 7–9 moderate DTS, and ≥10 were defined as severe DTS. Subjects who slept less than 7 h were considered as short sleepers. Finally, data were collected, entered, tested for normality and analyzed using descriptive, univariate (χ2 test) and multivariate (Kruskal–Waills test) packages of SPSS version (21). Results: The predominant sleep patterns among Omanis were either polyphasic having more than two sleep periods per day (49.60%) or biphasic having two sleep periods (42.4%). The sleep patterns were not associated with gender (p = 0.888) or age (p = 0.06). However, there was an obvious trend between sleep patterns and age; younger and elderly groups expressed higher prevalence toward polyphasic pattern (54.81% and 68.00 % respectively). Night sleep duration was insignificant (p = 0.063) among all sleep patterns with an average of 6.18 h. This was confirmed with elevated prevalence of short night sleepers (67.60%), which was dominant among biphasic and polyphasic sleepers. This was in contrast regarding the average sleep duration within 24 h. (p = 0.000). Polyphasic sleepers had longer sleep duration with an average of 7.96 h that was significantly attributed to long siesta (73.27%). Daytime sleepiness was significantly different across sleep patterns (p = 0.000) with an average of 8.97. Monophasic and biphasic patterns were associated with moderate DTS (6.74 and 8.60) (20.60%), whereas polyphasic pattern was linked to severe DTS (9.66) (52.80%). Furthermore, 47% were poor sleepers with an average score of 5.50. This was insignificantly different across all sleep patterns (p = 0.107) although the PSQI average score for polyphasic pattern (5.65) indicated poor sleep quality. Conclusion: Sleep pattern among Omanis is directed toward polyphasic, which is associated with short night duration, long siesta, and severe DTS, hence poor sleep hygiene and quality. Further studies will be conducted soon to associate between this sleep pattern of Omanis and cardio-metabolic risk using metabolic biomarkers. Acknowledgements: This work was supported by the College of Medicine in Sultan Qaboos University. Deep gratitude is extended to the committee members; Professor Mohammed Osman Hassan, Dr Mohammed Al-Abri, Dr Fahad Al-Zidjali, Dr Deepali, and Dr Gangoli, all volunteers, clinical technicians and my family members for their input, support and guidance. http://dx.doi.org/10.1016/j.sleep.2015.02.081
Impaired postural stability in sleep disordered breathing patients F. Degache 1, Y. Goy 2, S. Vat 3, J. Haba Rubio 3, O. Contal 1, R. Heinzer 3 1 University of Health Sciences, Health Research Unit, University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland 2 Institute of Sports Sciences, Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland 3 Center for Investigation and Research in Sleep (CIRS), University Hospital of Lausanne (CHUV), Switzerland