Helicobacter pylori (H pylori) infection carries an overall relative risk of 3.3 (95%CI, 2.6-4.4) for developing PUD. A synergistic relationship exists between H pylori infection and NSAID´s consumption for developing PUD with an overall risk of 3.5 (95%CI, 1.26-9.96) compared to either H pylori or NSAID´s negative individuals. Furthermore, a 61.1 (95%CI, 9.98-373) overall risk exist when compared to H pylori negative individuals not taking NSAID´s. For marginal ulcers after RYGB, three cohort studies have showed that H. pylori infection is not associated with the development of marginal ulcers. In Papasavas et al study, preoperative H. pylori testing with prophylactic eradication did not decrease the incidence of MU or erosive pouch gastritis.