Sleep Position and Sleep Apnoea: Is There a Relationship?

sleep positionIs there a relationship between body posture and sleep apnoea? Indeed there is. There are some experts who say that if you avoid the supine position, you will experience a decrease in the number and severity of obstructive episodes. This is because when the body is in a supine position, the upper airway calibre and resistance are greater and the upper airway has the tendency to collapse further. This is why some experts recommend the lateral position instead of the supine position during sleep. If you avoid the supine position during sleep, there would be greater symptomatic improvement.

Some studies have actually classified patients with obstructive sleep apnoea into two groups: positional and non-positional. Positional patients are those in whom the respiratory disturbance index was more than twice as high in the supine position as it was in the lateral position. Nonpositional patients are those in whom supine RDI was less than two times higher than the lateral RDI. It is said that 9 to 60% of patients with obstructive sleep apnoea are of the positional type. These patients are also observed to be thinner and younger and have less severe breathing abnormality indices compared to nonpositional patients. They also have smaller neck circumference and spend more time in the supine posture as a percentage of total sleep time. The optimal CPAP pressures required for positional patients was significantly lower than that for nonpositional patients.

So what is the mechanism behind positional sleep apnoea? It is said that during sleep, when in a prone position, the neck is rotated and the head is positioned laterally. When a person sleeps on his/her side, both the body and head are positioned laterally. Turning from the prone posture to the side or supine position decreases the upper airway size in nonpositional patients by decreasing the lateral distance, while the opposite effect was found in the positional patients.

It is also said that there may be a decrease on pharyngeal area diameter observed when patients with obstructive sleep apnoea changed their posture to supine.

A recent review by Menon et. al determined the relationship between sleeping body posture and severity of obstructive sleep apnoea. A systematic review of the published English literature during a 25-year period from 1983 to 2008 was performed. The results showed that published data concerning the sleep apnoea severity and posture in adults are limited. Supine sleep posture is consistently associated with more severe obstructive sleep apnoea indices in adults. However, the relationship between sleep apnoea severity indices and prone posture is inconsistent.

The authors claimed that supine sleep posture is consistently associated with more severe obstructive sleep apnoea indices in adults, but this appears to be less consistent in paediatric patients. Published data concerning adults in prone position are limited and not consistent. Further study of prone position in adults is needed.

Reference:

Menon A, Kumar M. Influence of Body Position on Severity of Obstructive Sleep Apnoea: A Systematic Review. ISRN Otolaryngol. 2013 Oct 8;2013:670381.

Image courtesy of artur84 / www.freedigitalphotos.net

Somnowell Inventor - Visiting Professor Simon Ash FDS MSc MOrth BDS

Prof. Ash is the inventor of the highly successful SOMNOWELL Chrome device for snoring and sleep apnoea.

The Somnowell Chrome is made to exacting standards in the Somnowell laboratory under the supervision of Visiting Professor Simon Ash. Prof. Ash and his master technicians create each Somnowell Chrome device using their wealth of experience and expertise.

Prof. Ash works at the forefront of his profession. He is a Consultant and Specialist Orthodontist with over 30 years clinical experience, with a special interest in sleep related breathing disorders, TMJD, and bruxism. He currently works in Harley Street London and two private hospitals in London as part of a multi-disciplinary team managing snoring and sleep apnoea, and is Visiting Professor of Orthodontics at the BPP University.