On hold due to poor enrollment and high drop-out rate.

Obesity has become a significant health problem in Canada. It is known to be a risk factor for many diseases, including Gastro-Esophageal Reflux Disease (GERD). When medical efforts to lose weight fail, patients often consider bariatric surgical procedures as the next step. The two most common bariatric procedures performed are Roux-en-Y Gastric Bypass (LRYGB) and Laparoscopic Sleeve Gastrectomy (LSG). The gold standard for diagnosing GERD is Esophageal pH monitoring, as it is the most objective method to document the reflux, assess the severity and monitor the response to treatment of the disease. In the last few years LSG has gained in popularity due to its simplicity and short operative time. Currently the comparison between bariatric surgery and GERD symptoms is very one sided. There are significant numbers of studies with conclusive results that state that LRYGB has a positive effect on GERD symptoms, however there is little evidence that states the same about LSG. This means that the relationship between LSG and GERD is inconclusive. An objective evaluation of GERD using 24 hour pH monitoring and validated CRFs at different follow up time points will contribute greatly to our understanding of what this relationship might be.

Inclusion Criteria:

• Fulfilled criteria for bariatric surgery as coined by National Institutes of Health conference.
• Their age is ≥18 years and ≤70 years
• The group with symptoms of GERD needs to have diagnosis of GERD in their medical record and taking proton pump inhibitors on a daily basis.
• Able and willing to give written consent
• The patient is willing to perform the pre-operative tests required for this study.
• The patient fits for both surgeries - LSG or LRYGB

Exclusion Criteria:

• Previous bariatric surgery
• Previous anti reflux procedure
• Contra-indication to general anesthesia
• Any medical condition, which in the judgment of the Investigator and/or designee makes the subject a poor candidate for the investigational procedure
• Pregnant or lactating female (Women of child bearing potential must take a pregnancy test prior to surgery)
• Hiatal hernia above 4cm (measured in the pre-operative gastroscopy).
• Multiple surgeries in abdominal cavity or previous small bowel disease/resection
• Patient on CPAP treatment for his OSA disease