A team led by Dr. J. Barry O’Connor at Duke University Medical Center recently determined that continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) can also ease symptoms of gastroesophageal reflux disease (GERD). While O’Connor and colleagues found that treating obstructive sleep apnea helped alleviate GERD, this is by no means the first indication that the two diseases are closely related. Some physicians believe that OSA results in pressure changes that encourage GERD, while others suggest that GERD’s characteristic acid backup may result in vocal cord spasms, leading to OSA. Although the truth may lie on one side or the other, or even in between, it is becoming increasingly clear that when treating either OSA or GERD, both conditions often improve.
The American Sleep Apnea Association estimates that approximately twelve million Americans experience some symptoms of OSA. The condition is characterized by a relaxation of the soft tissue towards the back of the neck, resulting in closed or partially obstructed air passages. The resulting oxygen deprivation causes the patient to wake up frequently during the night, disrupting normal sleeping patterns.
Notably, two key risk factors for OSA, obesity and high alcohol consumption, have also been identified as contributors of GERD. Gastroesophageal reflux affects as many as 20% of Americans once a week or more, with heartburn as the most reported symptom. If left untreated, the acid back flow that accompanies this condition can also lead to more serious problems such as esophagitis, Barrett’s esophagus, or even cancer.
A potential physiological link between OSA and GER has been further suggested by the work of O’Connor et al., indicating that CPAP devices treat OSA and heartburn simultaneously.
The Duke University Medical Center team began with the knowledge that nocturnal gastroesophageal reflux (nGER) is common in patients with OSA. Of 331 patients with OSA who were asked to grade their nGER symptoms on a scale from 1 (never) to 5 (always), a substantial 62% (204) reported symptoms of nGER. All the patients were started on a treatment program of continuous positive airway pressure to alleviate their OSA.
Significantly, follow-up studies showed that patients who continued with the program of CPAP treatment had an average decrease in score of nGER symptoms from 3.38 to 1.75, or 48%. On the contrary, patients who failed to follow the CPAP regimen showed no improvement in their nGER score. O’Connor and colleagues also found that patients using higher CPAP pressures showed the most improvement in their nGER scores.
The results of the O’Connor study seem to indicate that a CPAP device may treat both obstructive sleep apnea and gastroesophageal reflux disease. The device consists of a facemask connecting to a pump that acts to force air through the nose at pressures high enough to overcome any physical obstructions. According to O’Connor, the CPAP device "works by raising the pressure in the chest. CPAP elevates the pressure in the esophagus and keeps acid from coming up."
Short of surgery, many physicians consider CPAP the best means for treating sleep apnea, and this additional benefit makes it an even more attractive option.
Just as CPAP treatment of OSA seems to help reduce GERD, yet another study authored by Dr. M. Benninger has shown that antacid treatments of GERD can, in turn, alleviate apnea. Benninger and colleagues conducted a trial to determine how much GERD contributes to incidence of OSA. In their study, ten men ages 20 – 64 with confirmed OSA were treated for thirty days with omeprazole, a drug which acts to suppress acid production in the stomach. Significantly, the results showed a 31% decrease in the mean apnea index, as well as a 25% decrease in respiratory disturbances.
It is clear from the work of O’Connor, Benninger, and others that obstructive sleep apnea and gastroesophageal reflux share an underlying connection. Although the exact basis for their relationship is still unclear, treatments such as CPAP and omeprazole continue to show promise as a means for treating both problems concurrently.
