Our blood pressure varies during the day. Good and deep sleep brings relaxation with it. As a result, our blood pressure drops (the so called “dipping”), when we go sleeping. In people with obstructive sleep apnea blood pressure remains high even during their sleep. In fact, it can even elevate slightly in nighttime, though the causes of this state are not known yet.

Some scientists connect blood pressure elevation at night to breathing problems, insufficient oxygen supply and low quality of sleep. Continuous positive airway pressure therapy (CPAP) is used to treat this problem. A special machine is meant to facilitate people with obstructive sleep apnea with breathing while they sleep. The matter is its effect is too modest.