Obstructive sleep apnea (OSA) is one of the most under appreciated causes of high blood blood pressure. In the 1700's when they first discovered the blood pressure cuff, very little to nothing is known about sleep. Having excluded the then known causes of sleep apnea, they called the most common form of high blood pressure as essential hypertension.
In the last 50 years, as we started testing for sleep disorders such as sleep apnea, what has been shown is that sleep apnea is a common contributor to many people with high blood pressure, especially if they also snore. What is sleep apnea?
Sleep apnea literally means pauses in breathing at night or during sleep.
This happens because the upper airway muscles are relaxed at night leading to partial or at times complete obstruction of the airway leading to increased sympathetic hyperactivity and elevated blood pressure.How does sleep apnea cause high blood pressure?
These episodes of apnea produce surges in systolic and diastolic pressure that keep mean blood pressure levels elevated at night. In many patients, blood pressure remains elevated during the daytime, when breathing is normal.
Contributors to this diurnal pattern of hypertension include sympathetic nervous system overactivity and alterations in vascular function and structure caused by oxidant stress and inflammation. How can sleep apnea be treated?
Treatment of OSA with nasal continuous positive airway pressure (CPAP) abolishes apneas, thereby preventing intermittent arterial pressure surges and restoring the nocturnal "dipping" pattern. Does treatment of sleep apnea help improve the blood pressure?
CPAP treatment also has modest beneficial effects on daytime blood pressure. Because even small decreases in arterial pressure can contribute to reducing cardiovascular risk, screening for OSA is an essential element of evaluating patients with hypertension. In research studies, treating sleep apnea is equal to one medication for blood pressure.About the Author
Dr. Prab R. Tumpati, MD is a board certified sleep, obesity and internal medicine physician and practices sleep in greater Philadelphia and New York City locations of W8MD Medical Weight Loss Centers - Lose Weight, Sleep Better and Live Longer!