Gastroesophageal Reflux Disease After Roux-en-Y Gastric Bypass: Pathophysiology and Management

Abstract

Introduction:

Patients with obesity are often affected by gastroesophageal reflux disease (GERD). Roux-en-Y gastric bypass (RYGB) is considered the ideal operation for patients with severe obesity and GERD. Although the majority of patients improve their reflux with the operation, some might persist symptomatic and others can even develop de novo GERD. The aim of this study was to determine pathophysiologic factors involved in the development of GERD after RYGB surgery and define potential treatments for this condition.

Materials and Methods:

Studies including patients with GERD before and after RYGB and/or analyzing possible GERD therapies were analyzed by the authors. Searches were conducted in PubMed, Cochrane Library, and Embase databases.

Results:

GERD can persist, worsen, or develop after RYGB. There are certain technical elements of the operation identified as potential risk factors for GERD. Medical therapy is effective in the majority of patients. Both endoscopic and surgical procedures can also help resolving GERD after RYGB.

Conclusions:

Although the majority of patients with GERD after RYGB can be effectively managed with medical therapy, some may require endoscopic or surgical treatment. Critical technical elements of RYGB should be considered to reduce the risk of postoperative GERD.

Introduction

Obesity represents a major public health problem with increasing prevalence and health care costs over the last decades.¹ It is well known that obesity represents a major risk factor for other clinical conditions such as cardiovascular disease, type 2 diabetes mellitus, osteoarthritis, and cancer among others.² Many studies have also demonstrated the direct relationship between obesity and gastroesophageal reflux disease (GERD).³ Moreover, a linear association between incidence of GERD and body mass index (BMI) score has been described, appearing to be “dose-dependent”: BMI <25 (23%), BMI 25–30 (27%), and BMI >30 (50%).^3,4

Several pathophysiologic mechanisms for the development of GERD in obese patients are proposed⁵:

Mechanical factors: Increased intraabdominal pressure, coexistence of hiatal hernia, and low basal pressure of the lower esophageal sphincter (LES).

Humoral factors: Increased level of adipocytokines such as interleukin 6 and tumor necrosis factor α.

Motility disorders: Delayed esophageal clearing time and delayed gastric emptying are some of the proposed mechanisms by which abdominal obesity causes GERD.

The main cause of GERD, however, appears to be the altered transdiaphragmatic pressure gradient owing to the increased intraabdominal pressure caused by the excessive abdominal fat, which ultimately leads to an increased intragastric pressure.⁶

At present, sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) are the most commonly performed bariatric procedures,⁷ and both have shown equal results in terms of weight loss at 5 years.^8,9 However, in the recently published 10-year results of the SLEEVEPASS trial, the percentage of excess weight loss was greater after RYGB (8.4 higher 95% confidence interval, 3.1–13.6).¹⁰ Although patients undergoing bariatric surgery have higher chances of remission of obesity-related conditions,¹¹ the effect on GERD varies among these two procedures.

The aim of this study was to determine pathophysiologic factors involved in the development of GERD after RYGB surgery and define potential treatments for this condition.

Materials and Methods

We performed a thorough literature review to better understand incidence, pathophysiology, and potential therapies of GERD after RYGB. Searches were conducted in PubMed, Cochrane Library, and Embase databases. Keywords utilized included bariatric surgery, gastroesophageal reflux disease, postoperative GERD, gastric bypass, and RYGB. Studies including patients with GERD after RYGB (improving, worsening, or developing de novo GERD) and/or analyzing possible therapies were all analyzed by the authors.

Results

Bariatric surgery and GERD

The anatomical modifications created in the angle of His by the SG and the increased intragastric pressure generated by a narrower stomach, explains the development of de novo or worsening preexisting GERD after SG. On the contrary, the RYGB appears to be the ideal operation for patients with GERD owing to its anatomic configuration: a small gastric pouch with less parietal cells and a long Roux loop that prevents the reflux from duodenal contents.¹²

A study using the national Bariatric Outcomes Longitudinal Database (BOLD) revealed that 32% of patients undergoing bariatric surgery had evidence of preoperative GERD,¹³ highlighting the prevalence of GERD within this population. However, despite the success of the operation, up to 24% of patients show persistence or new-onset GERD symptoms on the postoperative course.¹⁴

A recent systematic review and meta-analysis demonstrated that the prevalence of de novo GERD was 9.3% (179/1918) following SG, and 2.3% (37/1616) following RYGB.¹⁵ In addition, a greater incidence of GERD was shown in patients with diagnosis of hiatal hernia.^16,17

Summary of evidence and expert commentary

Current evidence confirms that the incidence of GERD is significantly higher after SG, as compared with RYGB. Patients with obesity and GERD should not undergo SG, because it is very likely that GERD will worsen in these patients.

Incidence of GERD after RYGB

A previous study analyzed a cohort of 152 patients with preexisting GERD who underwent RYGB, and showed a significant decrease in GERD-related symptoms, including heartburn (from 87% to 22%, P < .001), wheezing (from 40% to 5%, P < .001), and aspiration (from 14% to 2%, P < .01). Postoperatively, the use of proton pump inhibitors and H2 blockers also decreased significantly (<0.01).¹⁸ Madalosso et al. studied 53 patients with GERD and evaluated them preoperatively and at 6 and 39 months after the RYGB: the prevalence of typical reflux symptoms was significantly reduced from 58% to 15% and 9%, respectively (P < .001). Reflux esophagitis was found in 45%, 32%, and 19%, respectively (P = .002), and DeMeester scores reduced from 28.6 to 9.4 and 1.2, respectively (P < .001).¹⁹

Another study included 57 patients with persistent GERD who underwent RYGB. At a mean follow-up of 18 months, all patients experienced clinical improvement or no symptoms of GERD, concluding that RYGB should be the procedure of choice for morbidly obese patients with GERD.²⁰

Opposite to these findings, a Swedish population-based study of 2454 patients evaluated the risk of remaining or recurring reflux symptoms after RYGB with a median follow-up of 4.6 years. Postoperative reflux was defined as residual or recurring symptoms of GERD with requirement of acid-suppression medications beyond 6 months postoperatively. Of interest, 48.8% of patients persisted or recurred with GERD within 2 years of the operation and remained affected by GERD up to 10 years after surgery. The authors also found that age >50 years, female sex, associated comorbidities, and high-cumulative dose of preoperative anti-reflux medication were significant risk factors for postoperative GERD.²¹ Other studies with large databases have also reported that 40%–50% of patients persisted with symptoms or required acid-suppression medication within 1 year after bariatric surgery.^13,22

The persistence and/or onset of GERD often lead to the use of medication or rarely a surgical intervention.²³ The Swedish study showed that the prevalence of reflux requiring anti-reflux medication was ∼68% during 5 years after the procedure and the strongest risk factor for postoperative GERD was high-dose preoperative acid suppression.²¹

A study from Gorodner et al. analyzed a cohort of patients with objective evidence of GERD (i.e., abnormal pH monitoring) undergoing RYGB. They found that 69% of patients resolved GERD, 23% improved, and 8% remained with the same symptoms (P < .001). The DeMeester score decreased from 35.7 to 11 (P < .001).²⁴

Although there are some cases of persistence or de novo GERD after RYGB, it remains the most effective bariatric procedure to prevent postoperative esophagitis, as compared with one anastomosis gastric bypass and SG.²⁵

Table 1 summarizes current evidence regarding GERD before and after RYGB.

Table 1.

Summary of Current Evidence Regarding Gastroesophageal Reflux Disease Before and After Roux-en-Y Gastric Bypass

Author	Year	N	Pre RYGB	Post RYGB	Comments
Pallati et al.¹³	2014	31,642	(RYGB 61.6%). 32% had preoperative GERD: GERD score 2.80 ± 0.56	Rate of persistence/de novo GERD: 24%. Postoperative GERD score 1.33 ± 1.41 (P < .0001). Mean follow-up 6 months	GERD score improvement was best in RYGB patients (56.5%; 7955 of 14,078)
Santonicola et al.¹⁴	2022	45	51.1% had preoperative GERD	30.4% had persistence and 18.2% developed de novo GERD. Mean follow-up 99.9 ± 22.9 months	RYGB provides satisfactory weight loss and a high percentage of GERD symptoms resolution. However, ∼24.4% of patients complained of GERD symptoms at medium-term follow-up
Frezza et al.¹⁸	2002	435	64% had evidence of preoperative GERD, 87% manifested as heartburn. 44% had daily use of PPIs	Heartburn decreased to 22% and use of PPI to 9%. Mean follow-up 36 months	GERD was present in more than half of patients and >90% achieved significant improvement or resolution of their symptoms after RYGB
Madalosso et al.¹⁹	2016	53	64% had evidence of preoperative GERD, manifested as reflux esophagitis in 45%. Mean DeMeester score was 28.6	Persistence/de novo GERD was 23%, and DeMeester score decreased to 1.2 (P < .001). Mean follow-up was 39 ± 7 months	RYGB reduces GERD symptoms, improves reflux esophagitis, and decreases esophageal acid exposure for longer than 3 years
Perry et al.²⁰	2004	57	100% had evidence of preoperative GERD, 54.4% had daily use of PPIs	Postoperative use of PPI decreased to 5.3%. Mean follow-up 18 months	At a mean follow-up of 18 months (range, 3–30), all patients report improvement or no symptoms of GERD
Holmberg et al.²¹	2019	2454	NA	48.8% had persistence or de novo GERD. Mean follow-up 54 months	Risk factors for postoperative reflux were high preoperative dose of anti-reflux medication (IRR 1.77; 95% CI, 1.60–1.96 compared with low dose), older age (IRR 1.12; 95% CI 1.02–1.24 comparing age >50 with <40 years), female sex (IRR 1.28; 95% CI, 1.16–1.42) and comorbidity (IRR 1.26; 95% CI, 1.14–1.39 comparing Charlson Comorbidity Index ≥2 with 0)
Varban et al.²²	2015	6410	40.6% had daily use of PPI	Use of PPI decreased to 29.2% (P < .0001). Mean follow-up 12 months
Gorodner et al.²⁴	2021	95	100% had evidence of preoperative GERD. Mean DeMeester score was 35.7	31% had evidence of persistence/de novo GERD. Mean postoperative DeMeester score was 11 (P < .001). Mean follow-up was 12 months	LES pressure remained the same and DeMeester score decreased, while 69% of patients resolved their GERD

CI, confidence interval; GERD, gastroesophageal reflux disease; LES, lower esophageal sphincter; PO, postoperative; PPI, proton pump inhibitors; RYGB, Roux-en-Y gastric bypass.

Summary of evidence and expert commentary

Overall, most studies have shown that RYGB is an effective anti-reflux operation. Therefore, this operation continues to be the preferred procedure for patients with obesity and GERD referred for bariatric surgery. However, we should be aware that RYGB is not an infallible procedure for GERD as it was thought.

Pathophysiology of GERD after RYGB

Several mechanisms have been proposed to explain the development of GERD after RYGB. As it is well known that the area below the cardia contains the highest density of parietal acid-secreting cells in the stomach,²⁶ it is rationale to believe that a large pouch could be one of the main causes of GERD symptoms after RYGB. For this reason, to reduce acid production (and promote greater weight loss), the surgeon should try to calibrate the pouch as small as possible.

Bile reflux into the pouch has also been described after RYGB, suggesting that it may play a role in developing reflux symptoms. Swartz et al. reported that patients with endoscopic evidence of bile in the pouch presented a shorter alimentary limb in the revisional surgery 5 years after RYGB.²⁷ The authors concluded that an alimentary limb of at least 100 cm of length should be performed to prevent bile reflux.

Another hypothesis was suggested by Rebecchi et al. who described that an impaired motility of the Roux limb might cause postoperative GERD.²⁸ In their study, 44% of patients presented some degree of esophagitis 5 years after RYGB, and 75% of patients were exposed to weakly acid reflux. Of interest, esophageal peristalsis and LES pressure remained with no changes. The authors concluded that the abnormal exposition to weakly acid reflux might cause an altered motility in the Roux limb, and thereby, reflux symptoms.

Pouch migration into mediastinum configurating a post-RYGB hiatal hernia might also occur, and this could justify the persistence or appearance of GERD symptoms after RYGB.²⁹

Table 2 summarizes potential physiopathological mechanisms for the development of GERD after RYGB.

Table 2.

Pathophysiology of Gastroesophageal Reflux Disease After Roux-en-Y Gastric Bypass

Possible mechanisms of GERD after RYGB
Hiatal hernia
Large gastric pouch
Candy cane syndrome
Gastrogastric fistula
Impaired esophageal clearance
Esophageal motor dysfunction
Hypotensive lower esophageal sphincter or increased transient relaxations
Pouch stasis syndrome
Short alimentary limb
Roux-en-Y stasis syndrome
Mechanical obstruction

GERD, gastroesophageal reflux disease; RYGB, Roux-en-Y gastric bypass.

Summary of evidence and expert commentary

We have identified several technical elements of RYGB related to the development of GERD. For instance, a large pouch containing a high density of acid-secreting cells clearly contributes to symptoms and a short alimentary limb facilitates bile reflux. RYGB should be performed by experienced surgeons who respect critical technical steps of the operation. The gastric pouch should be calibrated as small as possible and the alimentary limb should be at least 100 cm in length.

Management of GERD after RYGB

Most patients with de novo or persistent GERD after RYGB will respond to acid-suppression therapy (i.e., proton pump inhibitors [PPIs]).³⁰ Nonetheless, some patients will remain symptomatic and might require endoscopic or surgical therapy. Before planning a revisional procedure, a thorough diagnostic workup to confirm GERD and to identify possible pathophysiologic factors involved is needed.

In patients with a notorious large pouch or candy cane syndrome, surgical adjustment of these anatomical concerns can be beneficial. Likewise, if a short alimentary limb is suspected, a revisional surgery should be contemplated. Hiatal hernia repair should always be considered when a large hiatal hernia is diagnosed in patients with postoperative GERD after RYGB refractory to PPIs. Augmentation of the hiatoplasty with the ligamentum teres hepatis has been previously proposed. This technique consists in reinforcing the LES with the ligamentum and restoring its competence with a new valve. Runkel et al. analyzed 307 hiatal hernia repairs after SG (n = 79), RYGB (n = 129), and one anastomosis gastric bypass (n = 99) and compared those with and without reinforcement with ligamentum teres. The novel cardiopexy using the ligamentum teres significantly reduced recurrence rates.³¹

Kawahara et al. also described a novel technique using the excluded stomach to configurate a Nissen-like fundoplication in association with hiatal hernia repair in a patient with GERD refractory to medical therapy 5 years after RYGB. There were no complications and the patient was asymptomatic 6 months after the procedure.³² Recently, a small case-series of 6 patients who underwent the mentioned procedure reported complete symptomatic relief after 1 month, and 4 of them stopped PPI treatment.³³ Other groups have published successful results in 2 patients using Toupet fundoplication³⁴ and Hill procedure.³⁵

The lower esophageal magnetic sphincter augmentation (LINX) has also been described as a potential treatment for patients with GERD after RYGB. A case-series of 13 patients undergoing LINX placement after bariatric surgery (SG and RYGB) reported successful outcomes with 9 of the patients stopping acid-suppression medication after the procedure. Two of them required endoscopic dilation after LINX placement.³⁶

Endoscopic treatment has also been used, yet only in small series of patients. Mattar et al. reported good outcomes using radiofrequency ablation (Stretta procedure) at the gastroesophageal junction (complete resolution of symptoms in 5/7 patients).³⁷ Many other endoscopic options with promising results are now available for large pouches in case of weight regain after RYGB, such as argon plasma coagulation, full thickness suturing transoral outlet reduction (S-TORe), and/or full thickness plicating TORe (ROSE technique). Although there is no strong evidence yet for endoscopic treatment of GERD after RYGB, it seems it could be a suitable option for these patients.³⁸ Studies with longer follow-up and larger number of patients are needed to confirm the effectiveness of endoscopic procedures in patients with GERD after RYGB.

Summary of evidence and expert commentary

Patients with GERD after RYGB should start with PPIs. In most cases, GERD symptoms will improve. For patients with refractory GERD, a thorough diagnostic workup is needed to determine potential causes of GERD. If an anatomical cause (e.g., large pouch, hiatal hernia, candy cane syndrome) is identified, a revisional surgery is possibly the best treatment option. Novel endoscopic procedures have shown promising results, but further studies with longer follow-up are needed to strongly recommend them to treat GERD in these patients.

Conclusions

RYGB remains the ideal operation for patients with severe obesity and GERD. However, we should be aware that some patients might not improve their reflux and others can even develop de novo GERD after RYGB. Although the majority of patients can be effectively managed with medical therapy, some may require endoscopic or surgical treatment. Therefore, critical technical elements of the operation should be considered to reduce the risk of postoperative gastroesophageal reflux.

Footnotes

Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.

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