Connection Between Body Position During Sleep and Findings from Full- Night Polysomnography in Patients with Obstructive Sleep Apnea

Sa？etak Aim: The aim of our study was to determine the association between body position during sleep and OSA severity in patients with newly diagnosed OSA after full-length polysomnography. Subjects and Methods: We conducted a cross-sectional and clinical study involving 414 subjects (281 men and 133 women) older than 18 whose median age was 55 years. In 2017, subjects came to the Center for Sleep Medicine at UHC Split and the Split School of Medicine and their dana was taken from the archives of the same center. All patients did a full-night polysomnography after which the severity of OSA was estimated with the help of AHI in accordance with the OSA diagnosis guidelines prescribed by the American Academy of Sleep Medicine (AASM) and European Sleep Research Society (ESRS). Excessive daily sleepiness has been estimated by the Epworth Sleepiness Scale (ESS). Results: Statistical analysis showed that patients had spent more time on the back (189.9±118.4min) than on the left (113.3±90.9min) or right side (80.6±90.6min) during sleep and had the most sleep apneas on their back (AHI = 31.1±31.9). Patients with diagnosed OSA (AHI≥5) also had higher AHI values on the back (39.1±31.9) than on the left (23.8±25.2) or right side (18.5±25.6) during sleep. Patients with diagnosed OSA in comparison to patients without OSA diagnosis had statistically significantly higher BMI (29.5±4.6kg/m2 vs. 25.3±4.1kg/m2, P<0.001) and neck circumference (42.0±4.4cm vs 37.4±3.9cm, P<0.001). Overall, considering the whole sample, men were taller (180.8±7.4cm than 165.9±6.7cm, P<0.001), had higher BMI (29.4±4.5kg/m2 compared to 26.8±4.9kg/m2, P<0.001 ) and bigger neck circumference (43.2±3.5cm vs. 36.2±3.4cm, P=0.002), as well as a larger ESS sum (7.6±4.7 compared to 6.3±4.8, P=0.021). Using the Pearson Correlation Coefficient, we showed a negative correlation of AHI with sleep time on the right side (r=-0.178, P=0.005) in OSA patients, while positive correlation was found in sleep on the left side (r=0.003, P=0.959) and back (r=0.183, P=0.002). Conclusion: Our research showed that patients sleep the most time n their back and that AHI ist the highest in that sleep position in comparison to other sleep position which worsens sleep quality in the long term