Obstructive sleep Apnea is very serious. It can cause 19 different medical problems, but the biggest thing is fatigue, not feeling restored from your night's sleep. So people are at risk for not living the healthiest lives they can and falling asleep at inappropriate times, like behind the wheel of a car. What we know is that more car accidents occur in Friday night, independent of alcohol than any other time of the week. Because people are sleep deprived.