Background/Aims:The aim of this study is to investigate the degree of delayed gastric emptying (DGE) and evaluate how the severity of DGE affects gastroesophageal reflux disease (GERD) in neurologically impaired (NI) patients utilizing 24-hour multichannel intraluminal impedance pH measurements (pH/MII) and 13C-acetate breath test (13C-ABT) analyses. Methods:13C-ABT and pH/MII were conducted in 26 NI patients who were referred to our institution due to suspected GERD. At first, correlation analyses were performed to investigate the correlation between the 13C-ABT parameters and the clinical or pH/MII parameters. Thereafter, all patients were divided into 2 groups (DGE and severe DGE [SDGE] group) according to each cut off half emptying time (t1/2, 90-170 minutes). Each pH/MII parameter was compared between the 2 groups in each set-up cutoff t1/2. Results:The mean t1/2 of all patients was 215.5 ± 237.2 minutes and the t1/2 of 24 (92.3%) patients were > 100 minutes. Significant moderate positive correlations were observed between both t1/2 and lag phase time and the non-acid reflux related parameters. Furthermore, the patients in the SDGE group demonstrated higher non-acid reflux related parameters than those of the DGE groups when the cutoff was t1/2 ≥ 140 minutes. Conclusion:The present study demonstrated that GE with t1/2 ≥ 140 minutes was related to an increase of non-acid exposure reaching up to the proximal esophagus in NI patients, and indicating that NI patients with SDGE might have a high risk of non-acid GERD.