Sleep Apnea Numbers Underestimated in Atrial Fibrillation
A small study showed that patients with atrial fibrillation(AF) should be tested for sleep apnea with polysomnography instead of portable diagnostic methods, because portable methods can greatly underestimate the incidence of apnea in those patients.
Atrial Fibrillation is the most common form of abnormal heart beat (cardiac arrhythmia). Any sort of irregular heart rhythm can cause depression and eventual mortality. Sleep apnea, or the cessation of breathing during sleep, greatly increases the risk of AF, particularly when left untreated.
Researches used both polysomnography (PSG) and portable monitoring devices to record 30 AF patients while t hey slept. Researchers monitored nasal flow, movements of breath and oxygen desaturation. They also had patients hooked up to an ECG, or electrocardiogram, to monitor heart rhythms.
Using the portable polygraphy tests 17 of the 30 subjects were identified as having sleep disordered breathing. 13 were diagnosed with mild sleep apnea, and 4 with moderate sleep disordered breathing.
Researchers did not find more cases of apnea when they switched to the PSG, but they did find that many of those 'mild' cases were in fact moderate, and the moderate cases should have been diagnosed as severe. The issue of a misdiagnosed severity comes with the treatment. For many mild cases doctors simply tell patients to use an apnea pillow or even just ignore the disorder, where moderate and severe cases are treated by issuing breathing devices.
Having the correct diagnosis and the correct treatment can greatly reduce the risk of death in those AF patients who suffer from sleep apnea, as well.
The study included both men and women with both paroxysmal and persistent cases of AF. The median age of participants in the study was 63.