Good day everyone, We know that you are enjoying your side sleeping experience on your KCE Bed! We wanted to share some scientific studies published on the National Institute of Health site. These studies show us how the Lateral (side) sleep position is beneficial to our health:
Influence of the right- versus left-sided sleeping position on the apnea-hypopnea index in patients with sleep apnea
- PMID: 21678115
- DOI: 10.1007/s11325-011-0547-4
Purpose: Sleep and sleep position have a significant impact on physical, cardiac and mental health, and have been evaluated in numerous studies particularly in terms of lateral sleeping positions and their association with diseases. We retrospectively examined the relationship between the sleeping position and position-specific apnea-hypopnea index (AHI) in obstructive sleep apnea-hypopnea (OSA) patients.
Methods: We assessed the sleeping body position and the body position-specific AHI score in patients who were referred for suspected OSA and underwent diagnostic nocturnal polysomnography. In order to eliminate inter-individual differences, only those who had a similar percentage of time spent in the LSSP and RSSP for each patient were enrolled. To provide this validity, only subjects that had a similar percentage of left and right lateral sleep time (±10%) were included in the analysis.
Results: A total of 864 patients had nocturnal diagnostic PSG. Of them, 131 patients met the inclusion criteria. The percent rate spent in the supine sleeping position (SSP) was 31.3 ± 18.7%, in the LSSP was 31.8 ± 10% and in the RSSP was 32.6 ± 10.8%. Whereas the SSP-specific AHI score was the highest with 60.4 ± 36.2/h among all the sleeping position-specific AHI scores (p < 0.001), the LSSP-specific AHI score was statistically higher than that for RSSP (30.2 ± 32.6/h vs. 23.6 ± 30.1/h; p < 0.001). When comparing individuals sub-grouped based on OSA severity, there was a statistically significant
difference between the LSSP-specific AHI score and RSSP-specific AHI score in patients with severe (p = 0.002) and moderate (p = 0.026), but not mild (p = 0.130) OSA.
Conclusion: We found that the sleeping position had a significant influence on apneic events and RSSP decreased the frequency of obstructive respiratory events in patients with moderate and severe disease.
Randomized Controlled Trial
A Novel Sleep Positioning Device Reduces Gastroesophageal Reflux:
- PMID: 26053170
- DOI: 10.1097/MCG.0000000000000359
Goal: We hypothesized that sleeping left-side down with the head/torso elevated reduces recumbent gastroesophageal reflux (GER).
Background: Previous studies show that sleeping with head of bed elevated or on wedge reduces GER and lying left-side down reduces GER versus right-side down and supine. No prior studies have evaluated the potential compounding effects of lying in an inclined position combined with lateral positioning on GER.
Study: We evaluated a sleep-positioning device (SPD) consisting of an inclined base and body pillow that maintains lateral position while elevating the head/torso. This was a single institution, randomized controlled trial involving 20 healthy volunteers receiving 4 six-hour impedance-pH tests. After placement of reflux probe, subjects returned home, ate standardized meal, and lay down in randomly assigned positions: SPD right-side down (SPD-R), SPD left-side down (SPD-L), standard wedge any position (W), or flat any position (F). A wireless accelerometer documented position during each study. Number of reflux episodes (RE) and esophageal acid exposure (EAE) were calculated over 6 hours.
Results: Significantly less EAE occurred during sleeping SPD-L versus sleeping W, SPD-R, and F. The most EAE occurred during sleeping SPD-R despite use of the positioning device. RE were significantly less SPD-L than SPD-R. Patients sleeping SPD-L and SPD-R spent the majority of first 2 hours and greater than half of 6 hours in assigned position. Patients sleeping W and F averaged more time supine than right or left.
Conclusions: The sleep positioning device maintains recumbent position effectively. Lying left-side down, it reduces recumbent esophageal acid exposure.
Collapsibility of the internal jugular veins in the lateral decubitus body position: A potential protective role of the cerebral venous outflow against neurodegeneration
- PMID: 31526984\
- OI: 10.1016/j.mehy.2019.109397
Recent research has revealed that patients with neurodegenerative disease sleep longer in the supine position, while healthy controls prefer sleeping in the lateral decubitus position. Thus, sleeping in the lateral position seems to be protective against neurodegeneration. It has also been suggested that a protective role of this body position could be associated with better cerebral venous drainage in this body position, which results in more active glymphatic system of the brain (the system responsible for clearance of the cerebral tissue from waste products, e.g., amyloid-β). Since no published evidence exists regarding venous outflow from the cranial cavity in the lateral decubitus position, we performed a pilot sonographic study of the internal jugular veins in 3 young healthy volunteers and 2 patients presenting with abnormal jugular valves. In all healthy volunteers both internal jugular veins were opened in the supine position and collapsed in the sitting one. In the right lateral decubitus position the right internal jugular vein was opened, while the left one was partially collapsed; and-vice versa-in the left lateral decubitus position the right internal jugular vein was partially collapsed and the left one opened. In patients with abnormal jugular valves both internal jugular veins were opened in both lateral decubitus body positions. We hypothesize that in the lateral decubitus body position, because of decreased flow resistance in the extracranial veins, cerebral venous outflow is optimal, which in turn optimizes the activity of the glymphatic system. Therefore, people intuitively prefer this body position during sleep, while other positions are associated with a higher risk of neurodegenerative disorders. Yet, it should be emphasized that our results need to be interpreted with caution, since only a few individuals have been assessed and this discovery should be confirmed in more patients and healthy controls, and by precise quantitative measurements.
Keywords: Alzheimer’s disease; Glymphatic system; Internal jugular vein; Lateral decubitus position; Neurodegeneration; Sleep.
The role of body position and gravity in the symptoms and treatment of various medical diseases
- PMID: 15551157
Postural medicine studies the effects of gravity on human body functions and the ability to influence various diseases by changing the body’s position. Orthostasis requires numerous cardiovascular and neurohumoral adaptations to prevent hypotension and a resulting decrease in cerebral perfusion. Sitting upright or in a semi-sitting position reduces venous return in patients with heart failure, intracranial pressure in patients with intracranial hypertension, intraocular pressure in glaucoma patients and may decrease gastro-oesophageal reflux. A left recumbent posture also decreases reflux. A right lateral position results in a lower sympathetic tone than lying on the left side and is beneficial in patients with heart failure or after an infarction without bradycardia. A 40 to 70% decreased prevalence of the sudden infant death syndrome has been observed since the recommendation to avoid laying infants to sleep in a prone position. Sleeping in a supine posture increases the severity of sleep apnea compared to a lateral position. In patients with acute respiratory distress syndrome, a prone position can rapidly improve blood oxygenation. Idiopathic oedema, orthostatic proteinuria, intradiscal pressure and venous circulation in legs are improved in the decubitus position, whereas arterial flow is reduced. Health risks due to microgravity and prolonged bed rest, such as osteoporosis, venous thrombosis or pressure sores, are discussed.