The objective of the study is to analyze procedural and safety outcomes associated with bariatric surgery and describe the characteristics of patients undertaking bariatric procedures in England between April 2006 and March 2012.

This is a retrospective cohort study of all adult patients in England diagnosed with obesity and undergoing bariatric surgery as a primary procedure in NHS-funded sites between April 2006 and March 2012 using data sourced from the Hospital Episode Statistics dataset. Length of stay (LOS), 30-day readmission, and post-surgery complication were analyzed as primary outcomes. Socio-demographic background, provider type, procedure volume, and comorbidities were all analyzed as potential explanatory variables.

Gastric bypass (GBP, 12,628) was the most utilized procedure, followed by gastric banding (GB, 6872) and sleeve gastrectomy (SG, 3251). The most prevalent comorbidity was type 2 diabetes (23%). Inpatient mortality was low (≤ 0.15%) for all procedure types. LOS and the risks of both post-operative complication and 30-day readmission were significantly lower for GB, relative to those for GBP and SG. Ethnicity, geographical area, surgery type, and volume were all associated with LOS, risk of readmission, and complication. Provider type and deprivation were further associated with LOS while age correlated with readmission only. An increasing comorbidity burden was associated with an increased risk of both readmission and complication.

Gastric bypass was the most frequently reported procedure in England across the observation period. While utilization across all procedure types increased between 2007 and 2010, overall uptake of bariatric surgery in England represents only a small proportion of the eligible population. Readmission and complication rates were lower for gastric banding relative to those for either gastric bypass or sleeve gastrectomy. The observed inpatient mortality rate was low across all procedure types.