[Obstructive sleep apnea: factors important for severe daytime sleepiness]

Abstract

The aim of the study - to investigate which of the following clinical (age, gender and weight) and polysomnographic data (respiratory disturbance index, duration of slow sleep, mean and maximum desaturation percent, arousal index) the most important for the daytime sleepiness in patients with obstructive sleep apnea syndrome. Obstructive sleep apnea was confirmed by polisomnography (ALICE 4 system). Daytime sleepiness was investigated using Epworth sleepiness scale (ESS). One hundred eight consecutive patients with obstructive sleep apnea were included in the study: 77 men (age 52.4+/-12.84 years) and 31 women (age 59.5+/-9.58 years). Correlation of ESS value and patients' weight was 0.32, p=0.001, ESS and respiratory disturbance index was 0.493, p<0.001, ESS and slow sleep time was -0.39, p<0.001, ESS and arousal index was 0.509, p<0.001, ESS and mean desaturation value was -0.352, p=0.001, and ESS and maximal desaturation value was -0.398, p<0.001. Logistic regression model was used to determine the role of gender, age, obesity degree (according to the body-mass index) and polysomnographic data for severe daytime sleepiness (ESS more than 10). In the univariate analysis male had odds ratio 3.52 (95% CI 1.35-9.16, p=0.01). In case of respiratory disturbance index is more than 34 - odds ratio was 4.25 (95% CI 1.85-9.76, p=0.001), slow sleep less than 38 minutes - odds ratio 3.08 (95% CI 1.38-6.9, p=0.006), mean desaturation less than 90% - odds ratio 4.09 (95% CI 1.68-9.96, p=0.002), maximal desaturation less than 80% 3.06 (95% CI 1.29-7.22, p=0.011), arousal index more than 30 - odds ratio 6.12 (95% CI 2.57-14.78, p<0.001). Only arousal index was statistically significant for the high daytime sleepiness in the multivariate analysis: odds ratio - 6.16 (95% CI 2.6-14.8, p<0.001).