Previous studies have shown that people with GER have problems sleeping, but researchers have not been able to show that reflux can lead to complete obstruction of the airway, a condition known as obstructive sleep apnea syndrome (OSAS). During sleep, a person with OSAS stops breathing, which causes them to wake up. In sleep centers, researchers record these sleep events (the number of times a person stops breathing and wakes up).
"Patients with OSAS have substantial nocturnal GER," said the study's lead researcher Brian P. Mulhall, M.D., M.P.H., of Walter Reed Army Medical Center's Gastroenterology Service (Washington, D.C.). "Our preliminary findings suggest that there may be a causal relationship between GER events and sleep events in patients with OSAS."
For the sleep study, patients were monitored either with the traditional pH probe (to measure acid reflux) or with the MII catheter, which can detect and measure reflux of any type, not just acid reflux. The MII catheter seemed better able to capture the non-acid reflux that might play a role in sleep apnea and arousals.