Abstract
Objective
The aim of this study was to characterize excessive daytime sleepiness (EDS) in a large cohort of Chinese patients with various severity of obstructive sleep apnea–hypopnea syndrome (OSAHS), and investigate its correlations with clinical/polysomnographic variables.
Materials and methods
A total of 1,035 consecutive Chinese patients with snoring (mean age ± SD 45 ± 15 years, BMI 26.6 ± 4.3 kg/m2) were examined by overnight polysomnography, and subjective EDS was assessed using the Epworth Sleepiness Scale (ESS).
Results
The 1,035 patients were compared according to severity of sleep-disordered breathing: AHI <5 (primary snoring group or normal overall AHI) (24.1%), AHI 5–20 (mild OSAHS, 21.7%), AHI >20–40 (moderate OSAHS 16.5%), and AHI >40 (severe OSAHS 37.7%). ESS score progressively increased as the severity of OSAHS aggravated among these patients. More severe OSAHS patients were characterized by EDS, nocturnal hypoxemia, and disruption of sleep structure. Progressive worsening of nocturnal hypoxemia was observed from mild to severe OSAHS patients with a strong correlation with ESS score. The stepwise multiple regression analysis performed to evaluate the correlations of individual clinical and polysomnographic variables with the ESS score revealed that the ESS score significantly correlated with the oxygen desaturation index (ODI), apnea–hypopnea index (AHI), and body mass index (BMI), and ODI was the strongest determinant of ESS score.
Conclusion
EDS is correlated with the severity of OSAHS. More severe patients are characterized by higher ESS score, higher BMI, and progressive worsening of nocturnal hypoxemia. Nocturnal hypoxemia is a major determinant of EDS in Chinese OSAHS patients.
Similar content being viewed by others
References
Douglas NJ, Polo O (1994) Pathogenesis of obstructive sleep apnoea/hypopnoea syndrome. Lancet 344:653–655. doi:10.1016/S0140-6736(94)92088-5
Jurkovicova I, Celec P (2004) Sleep apnea syndrome and its complications. Acta Med Austriaca 31:45–50
Banno K, Kryger MH (2007) Sleep apnea: clinical investigations in humans. Sleep Med 3:400–426. doi:10.1016/j.sleep.2007.03.003
Verstraeten E, Cluydts R, Pevernagie D, Hoffmann G (2004) Executive function in sleep apnea: controlling for attentional capacity in assessing executive attention. Sleep 27:685–693
Barbé F, Pericás J, Muñoz A, Findley L, Antó JM, Agustí AG (1998) Automobile accidents in patients with sleep apnea syndrome. An epidemiological and mechanistic study. Am J Respir Crit Care Med 158:18–22
Gami AS, Howard DE, Olson EJ, Somers VK (2005) Day–night pattern of sudden death in obstructive sleep apnea. N Engl J Med 352:1206–1214
Colt HG, Haas H, Rich GB (1991) Hypoxemia vs sleep fragmentation as cause of excessive daytime sleepiness in obstructive sleep apnea. Chest 100:1542–1548. doi:10.1378/chest.100.6.1542
Dixon JB, Dixon ME, Anderson ML, Schachter L, O'brien PE (2007) Daytime sleepiness in the obese: not as simple as obstructive sleep apnea. Obesity 15:2504–2511. doi:10.1038/oby.2007.297
Goncalves MA, Paiva T, Ramos E, Guilleminault C (2004) Obstructive sleep apnea syndrome, sleepiness, and quality of life. Chest 125:2091–2096. doi:10.1378/chest.125.6.2091
Roure N, Gomez S, Mediano O, Duran J, Peña M, Capote F, Teran J, Masa JF, Alonso ML, Corral J, Sanchez-Armengod A, Martinez C, Barcelo A, Gozal D, Marin JM, Barbe F (2008) Daytime sleepiness and polysomnography in obstructive sleep apnea patients. Sleep Med 9:727–731. doi:10.1016/j.sleep.2008.02.006
Mediano O, Barceló A, de la Peña M, Gozal D, Agustí A, Barbé F (2007) Daytime sleepiness and polysomnographic variables in sleep apnoea patients. Eur Respir J 30:110–113. doi:10.1183/09031936.00009506
Johns MW (1991) A new method for measuring daytime sleepiness: the Epworth Sleepiness Scale. Sleep 14:540–545
Chan EY, Ng DK, Chan CH, Kwok KL, Chow PY, Cheung JM, Leung SY (2009) Modified Epworth Sleepiness Scale in Chinese children with obstructive sleep apnea: a retrospective study. Sleep Breath 13:59–63. doi:10.1007/s11325-008-0205-7
Chen NH, Johns MW, Li HY, Chu CC, Liang SC, Shu YH, Chuang ML, Wang PC (2002) Validation of a Chinese version of the Epworth Sleepiness Scale. Qual Life Res 11:817–821. doi:10.1023/A:1020818417949
Rechtschaffen A, Kales A (1968) Manual of standardized terminology, techniques and scoring system for the sleep stages of human subjects, vol. 204. US Government Printing Office, Washington, DC
Iber C, Ancoli-Israel S, Chesson AL, Quan SF (2007) The AASM manual for the scoring of sleep and associated events: rules, terminology and technical specifications. American Academy of Sleep Medicine, Westchester, Illinois (US)
Chinese Medical Association, Sleep Breathing Disorders Group (2002) Diagnostic and therapic manual for obstructive sleep apnea–hypopnea syndrome. Chin J Tuberc Respir Dis 25:195–198
America Academy of Sleep Medicine (2005) International classification of sleep disorders, 2nd ed.: diagnostic and coding manual. American Academy of Sleep Medicine, Westchester, Illinois
Young T, Peppard PE, Gottlieb DJ (2002) Epidemiology of obstructive sleep apnea: a population health perspective. Am J Respir Crit Care Med 165:1217–1239. doi:10.1164/rccm.2109080
Lavie P, Lavie L, Herer P (2005) All-cause mortality in males with sleep apnoea syndrome: declining mortality rates with age. Eur Respir J 25:514–520. doi:10.1183/09031936.05.00051504
Ferini-Strambi L, Baietto C, Di Gioia MR, Castaldi P, Castronovo C, Zucconi M, Cappa SF (2003) Cognitive dysfunction in patients with obstructive sleep apnea (OSA): partial reversibility after continuous positive airway pressure (CPAP). Brain Res Bull 61:87–92. doi:10.1016/S0361-9230(03)00068-6
Kyzer S, Charuzi I (1998) Obstructive sleep apnea in the obese. World J Surg 22:998–1001
Li KK, Powell NB, Kushida C, Riley RW, Adornato B, Guilleminault C (1999) A comparison of Asian and white patients with obstructive sleep apnea syndrome. Laryngoscope 109:1937–1940. doi:10.1007/s002689900506
WHO Expert Consultation (2004) Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies. Lancet 363:157–163. doi:10.1016/S0140-6736(03)15268-3
Ong KC, Clerk AA (1998) Comparison of the severity of sleep-disordered breathing in Asian and Caucasian patients seen at a sleep disorders center. Respir Med 92:843–848. doi:10.1016/S0954-6111(98)90386-9
Lim LL, Tham KW, Fook-Chong SM (2008) Obstructive sleep apnoea in Singapore: polysomnography data from a tertiary sleep disorders unit. Ann Acad Med Singapore 37:629–636
Knorst MM, Souza FJ, Martinez D (2008) Obstructive sleep apnea–hypopnea syndrome: association with gender, obesity and sleepiness-related factors. J Bras Pneumol 34:490–496
Bedard MA, Montplaisir J, Richer F, Malo J (1991) Nocturnal hypoxemia as a determinant of vigilance impairment in sleep apnea syndrome. Chest 100:367–370. doi:10.1378/chest.100.2.367
Gozal D, Kheirandish L (2005) Sleepiness and neurodegeneration in sleep-disordered breathing: convergence of signalling cascades. Am J Respir Crit Care Med 171:1325–1327. doi:10.1164/rccm.2503004
Zhan G, Fenik P, Pratico D, Veasey SC (2005) Inducible nitric oxide synthase in long-term intermittent hypoxia: hypersomnolence and brain injury. Am J Respir Crit Care Med 171:1414–1420. doi:10.1164/rccm.200411-1564OC
Zhan G, Serrano F, Fenik P, Hsu R, Kong L, Pratico D, Klann E, Veasey SC (2005) NADPH oxidase mediates hypersomnolence and brain oxidative injury in a murine model of sleep apnea. Am J Respir Crit Care Med 172:921–929. doi:10.1164/rccm.200504-581OC
Row BW, Liu R, Xu W, Kheirandish L, Gozal D (2003) Intermittent hypoxia is associated with oxidant stress and spatial learning deficits in the rat. Am J Respir Crit Care Med 167:1548–1553. doi:10.1164/rccm.200209-1050OC
Xu W, Chi L, Row BW, Xu R, Ke Y, Xu B, Luo C, Kheirandish L, Gozal D, Liu R (2004) Increased oxidative stress is associated with chronic intermittent hypoxia-mediated brain cortical neuronal cell apoptosis in a mouse model of sleep apnea. Neuroscience 126:313–323. doi:10.1016/j.neuroscience.2004.03.055
Acknowledgements
This study was supported by the Technology-Development Foundation of Suzhou (No. SS08036).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Chen, R., Xiong, Kp., Lian, Yx. et al. Daytime sleepiness and its determining factors in Chinese obstructive sleep apnea patients. Sleep Breath 15, 129–135 (2011). https://doi.org/10.1007/s11325-010-0337-4
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11325-010-0337-4