Sleep apnea is a common disorder associated with day time sleepiness and fatigue, and significant morbidity and mortality due to accidents and cardiovascular events (Vgontzas, Papanicolaou, Bixler, Hopper, Lotsikas, Lin, Kales & Chorousos, 2000). Male gender, advancing age, obesity, anatomical abnormalities (including small pharyngeal size due to fatty tissue of the neck), heredity and instability of respiratory control during sleep have been reported as risk factors for the development of sleep apnea (Vgontzas, Papanicolaou, Bixler, Hopper, Lotsikas, Lin, Kales & Chorousos, 2000). In a 1993 study, researchers from the University of Wisconsin's School of Medicine, examined the occurrence of sleep disordered breathing among middle aged adults (Young, Palta, Dempsey, Skatrud, Weber & Badr, 1993). In this randomised study of 602 men and women, aged 30 to 60 years, the estimated prevalence of sleep disordered breathing, defined as an apnoea-hypopnea score of 5 or higher, was 9 percent for women and 24 percent for men. Male sex and obesity were strongly associated with the presence of sleep disordered breathing.
Vgontzas, A.N., Papanicolaou, D.A., Bixler, E.O., Hopper, K., Lotsikas, A., Lin, H., Kales, A. & Chorousos, G.P. 2000. Sleep Apnea and daytime sleepiness and fatigue: relation to visceral obesity, insulin resistance, and hypercytokinemia. The Journal of Clinical Endocrinology & Metabolism, 85, 3,1151-1158.
Young, T., Palta, M., Dempsey, J., Skatrud, J., Weber, S. & Badr, S. 1993. The occurrence of sleep-disordered breathing among middle aged adults. New England Journal of Medicine, 328, 17, 1230-1235.