It is estimated that 22 million Americans suffer from sleep apnea, a disorder in which breathing during sleep repeatedly stops and starts. Sleep apnea is very common in neurological diseases like familial dysautonomia, as well as in multiple system atrophy, Parkinson disease, and related disorders. Sleep apnea can be life-threatening because the amount of oxygen in the blood can decrease during the breathing pauses. This can eventually result in arrhythmias and other ominous events. In fact, sudden death during sleep is one of the most frequent cause of death in patients with familial dysautonomia and multiple system atrophy. And this could be related to the presence of sleep apnea.
The most widely used and successful treatment for sleep apnea are positive airway pressure machines. These machines work by either continuously keeping the airway open (CPAP) or moving air in and out of the airways (BiPAP). The Continuous Positive Airway Pressure (CPAP) device is a small machine that supplies a constant and steady air pressure though a mask or nosepiece. This avoids the respiratory pauses during the apneas and improves the quality of ventilation during sleep.
As a recent study by Dr. Palma shows, using CPAP not only helps with ventilation and oxygenation but also normalizes the activity of the autonomic nervous system during sleep. The study, which was done in collaboration with the School of Medicine of Navarra (Spain), tested 30 patients with sleep apnea. It involved an initial sleep study in which not only the typical parameters were measured (oxygen saturation, sleep stages, etc.) but also some additional parameters obtained from the EKG that measured autonomic control of the heart. When compared to healthy controls, patients with sleep apnea had increased sympathetic and decreased parasympathetic autonomic control of the heart, a finding that could be contributing to the higher incidence of arrhythmias and cardiac problems in these patients.
When the patients were studied again, while using CPAP, their autonomic function was improved, even after using CPAP just for one night. After using CPAP for 2-years, the autonomic balance in the heart was completely restored – and similar to healthy subjects.
The findings show that using CPAP may not only support breathing at night, it may also have long-lasting beneficial effects on the autonomic control of the heart. This could potentially prevent arrhythmias during sleep and other cardiovascular problems. This is one more good reason to use CPAP!
Read the paper: Palma JA, Iriarte J, Fernandez S, Alegre M, Valencia M, Artieda J, Urrestarazu E. Long-term continuous positive airway pressure therapy improves cardiac autonomic tone during sleep in patients with obstructive sleep apnea. Clin Auton Res. 2015 Aug;25(4):225-32. doi: 10.1007/s10286-015-0297-7. PMID: 26001693