Background Diagnosing gastroesophageal reflux disease is challenging in the older population, as comorbid conditions can obscure the disease. Methods This prospective study included 97 participants: 25 healthy controls (group 1), 46 reflux patients aged 26-64 (group 2), and 26 patients over 65 (group 3). Esophageal motility was assessed using conventional esophageal manometry, and 24-h pH-metry and non-acid reflux episodes were assessed using multichannel intraluminal impedance. Results Among the older patients (group 3), 34% had reflux disease. The rate of lower esophageal sphincter insufficiency in group 3 was comparable with that in group 2 and significantly different from group 1. Gastric 24-h pH-metry showed no significant differences between the groups. Esophageal pH-metry results for groups 1 and 3 differed significantly from those in group 2. Impedance assessment showed that older patients have non-acid reflux episodes in the recumbent position significantly more often in comparison with controls and reflux patients. Reflux patients and older patients had proximal reflux episodes significantly more often than healthy Volunteers. Conclusions Patients aged over 65 have non-acid reflux, particularly in the recumbent position, significantly more often than normal individuals and patients with reflux disease. Non-acid reflux may mimic a negative DeMeester score in older patients with severe reflux disease.