Table 4.

Prospective studies on brain–gut behavior therapies for symptomatic GERD

Author	Study design	Subject	Intervention	Follow-up duration	Outcome
Glasinovic etal. (2018) [81]	Non-RCT	51 patients with pathological supragastric belching	Cognitive behavioral therapy	8 weeks	The number of supragastric belching episodes***, the number of acid reflux episodes***, and acid exposure time** decreased
Eherer etal. (2012) [84]	RCT	19 GERD patients	DB + PPI (n = 10) vs PPI (n = 9)	4 weeks	There was a significant decrease in acid exposure time and improvement in quality of life on DB + PPI but not PPI alone
Sun etal. (2016) [82]	RCT	40 GERD patients	DB + rabeprazole (n = 20) vs rabeprazole (n = 20)	8 weeks	DB + rabeprazole significantly enhanced anti-reflux barrier (crural diaphragm tension and gastroesophageal junction pressure) compared with rabeprazole alone
Halland etal. (2021) [83]	RCT	23 patients and 10 healthy volunteers	DB (n = 11 patients + 5 healthy volunteers) vs sham DB (remaining subjects)	2 days	DB significantly decreased lower esophageal sphincter pressure***, the number of reflux episodes***,and postprandial acid exposure*
Chandran etal. (2019) [88]	Non-RCT	120 GERD patients	Mindfulness-based stress reduction + PPI + lifestyle modification vs PPI + lifestyle modification	8 weeks	Intervention with mindfulness-based stress reduction led to overall improvement of symptoms (GERD-Health-Related Quality of Life and symptom scores)

DB, diaphragmatic breathing therapy; GERD, gastroesophageal reflux disease; PPI, proton-pump inhibitor; RCT, randomized–controlled trial; +, plus.

^* P < 0.05;

^** P ≤ 0.01;

^*** P ≤ 0.001.