Both apneas and hypopneas have very similar health consequences, and any one OSA sufferer will usually have both types of airway collapse. OSA patients may have over 100 episodes of airway collapse per hour in the most severe cases. Each episode of airway collapse is terminated by a brief 'arousal' which is a very short change in level of alertness during which normal breathing is resumed. Most patients don't wake up enough to remember the arousal and fall right back to sleep, although they may remember occasionally waking up gasping and short of breath during the night. The effect of these frequent arousal's is that sleep is not continuous or refreshing.
Patients frequently complain of inability to stay fully awake during the daytime.
Oxygen drops accompany the breath holding spells, and this may result in morning headaches. In long term apnea patients, we find an increased incidence of cerebrovascular disease. As researchers gather data, it appears that high blood pressure, strokes and heart attacks occur with increased frequency in OSA patients. Fortunately this is uncommon and usually treatment does not need to be initiated as an emergency. The sleep study will document the number of apneas and hypopneas that occur during the night as well as how often they cause arousal's and drops in oxygen levels.