A few studies have specifically looked into the reflux of nonacidic duodenogastroesophageal reflux (DGER).
National Library of Medicine's PubMed database was searched using keywords relating to DGER and the anatomic subsites of the upper aerodigestive tract.
Compared to the body of literature available on GER, there are few studies on the effects of DGER on the upper aerodigestive tract.
In their evaluation of 65 patients with symptomatic heartburn who were on proton pump inhibitor therapy, 38% had pathologic DGER alone, and 26% had both HCl reflux and DGER.
This study emphasized that the other elements of DGER were the cause of continued symptomology, explained why acid suppression was not helpful in these cases, and validated the use of impedance in cases where nonacidic reflux is suspected.