OSA is often combined with hypertension and is an important cause of secondary hypertension. Except for age, obesity, and smoking, OSA is a risk factor for hypertension. 50% to 92% of patients with OSA have hypertension, and 30% to 50% of patients with hypertension have OSA.
Is OSA a risk factor for hypertension?
Yes. OSA can cause recurrent episodes of hypoxemia, hypercapnia, sleep disruption, and sympathetic nervous system activation, all of which are thought to be associated with hypertension.
In addition, OSA has long been known to cause oxidative stress, endothelial dysfunction, metabolic disorders, sympathetic activation, and systemic inflammation in patients with intermittent hypoxia. All of these factors or some of them may also contribute to the development of atherosclerosis, and hypertension in patients who already have certain risk factors, usually like obesity. Treating obstructive sleep apnea (OSA) can also help treat hypertension.
Identifications of individuals at risk for obstructive sleep apnea-related hypertension:
Patients with high blood pressure should be alerted to the presence of sleep apnea if they have the following conditions: (1) Obesity. (2) Craniofacial abnormalities. (3) Snoring during sleep, excessive daytime sleepiness, headache and dry mouth in the morning. (4) Resistant hypertension or masked hypertension, morning hypertension, or non-dipping hypertension or anti-dipper blood pressure rhythm. (Individuals who experience a less than 10% reduction in nighttime BP are described as having a non-dipping BP pattern.) (5) Recurrent nocturnal episodes of uncontrollable angina pectoris. (6) Cardiac arrhythmias that are difficult to restore at night. (7) Intractable congestive heart failure. (8) Refractory diabetes and insulin resistance. (9) Unexplained pulmonary hypertension. (10) Unexplained nocturnal awakening or nocturnal seizures. |