Is Obstructive Sleep Apnea the New Kid on the Block?
Dai Yumino, M.D. Sleep Research Laboratory of the Toronto Rehabilitation Institute, Toronto, Canada T. Douglas Bradley, M.D. Sleep Research Laboratory of the Toronto Rehabilitation Institute and Toronto General Hospital of the University Health Network, Toronto, Canada Growing evidence from epidemiological studies suggests that obstructive sleep apnea (OSA) may be a treatable risk factor for hypertension as well as for atherosclerotic diseases (1–3). OSA elicits a cascade of noxious cardiovascular stimuli during sleep characterized by repetitive apnea-induced hypoxia, generation of exaggerated negative intrathoracic pressure, arousals from sleep, surges in blood pressure, sympathetic nervous system activation and parasympathetic withdrawal, as well as production of reactive oxygen species, vascular endothelial growth factors, and inflammatory mediators (4). Downstream, these factors promote trophic stimulation of the myocardium, vascular endothelial dysfunction, increased platelet aggr
