%0 Journal Article
%T Influence of Body Position on Severity of Obstructive Sleep Apnea: A Systematic Review
%A Akshay Menon
%A Manoj Kumar
%J ISRN Otolaryngology
%D 2013
%R 10.1155/2013/670381
%X Aim. The aim of this review is to determine the relationship between sleeping body posture and severity of obstructive sleep apnea. This relationship has been investigated in the past. However, the conclusions derived from some of these studies are conflicting with each other. This paper intends to summarize the reported relationships between sleep posture and various sleep indices in patients diagnosed with sleep apnea. Methods and Materials. A systematic review of the published English literature during a 25-year period from 1983 to 2008 was performed. Results. Published data concerning the sleep apnea severity and posture in adults are limited. Supine sleep posture is consistently associated with more severe obstructive sleep apnea indices in adults. However, relationship between sleep apnea severity indices and prone posture is inconsistent. 1. Background A few prior studies have addressed the relationship between body posture and sleep apnea. It has been observed that the avoidance of supine position leads to a decrease in the number and severity of obstructive episodes [1, 2]. In supine posture, the upper airway caliber and resistance are greater [3, 4]. Also, the tendency for the upper airway to collapse further is greater in supine position compared to lateral position [5, 6]. In patients with mild obstructive sleep apnea, symptomatic improvement may be achieved, simply by avoiding supine posture during sleep. In some patients, avoiding supine position while sleeping may be the only treatment required [7]. Some previously published studies have classified OSA patients into two groups: positional and nonpositional [8]. 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. The prevalence of positional patients among those with OSA varies from 9% to 60% [9¨C12]. In general, positional patients are thinner and younger and have less severe breathing abnormality indices compared to nonpositional patients. Also, patients with positional sleep apnea have smaller neck circumference and spend more time in the supine posture as a percentage of total sleep time [13]. Positional sleep apnea was reported as significantly more common when sleep apnea was mild than when it was moderate or severe [12, 13]. The optimal CPAP pressures required for positional patients were significantly lower than that for nonpositional patients [14]. The effect of prone sleep
%U http://www.hindawi.com/journals/isrn.otolaryngology/2013/670381/