In a cohort study of 166 patients followed for 11 years, Smith et al found preoperative response to acid-reducing medication, typical symptoms, and BMI < 35 Kg/m2 to predict successful outcome. However, HH size, normal 24-hour pH score, age > 50 years, female gender, and prior abdominal surgery that previous studies found to be associated with poor outcomes were not corroborated by this study. Other risk factors for failure are short esophagus, HH greater than 3 cm, and diaphragmatic stressors such as retching, sports of weight lifting, and high-speed motor vehicle accident among others.