Endocrine Abstracts

The relentless rise in the prevalence of obesity predicts an exponential increase in the incidence of obesity-related complications. Whereas preventative lifestyle measures must remain the cornerstone of management for the population at large, there remains a growing cohort of patients who remain in the severe obese (BMI>40 kg/m²) category and who suffer from the associated co-morbidities. Medical treatments may be sufficient for lesser degrees of obesity, for the amelioration of adverse cardiovascular risk profiles and to a degree in managing abnormal glucose metabolism. However, for patients with severe obesity, for those with significant medical complications and with either physical or psychosocial disability, surgical treatment remains the treatment of choice.

Surgical procedures for obesity aim to restrict the amount of foods that can be ingested (‘restrictive’ e.g. laparoscopic banding), to reduce the effective surface area of the gut available for absorption (‘malabsorptive’ e.g. bilio-pancreatic diversion) or combine elements of both (‘hybrid’ e.g. gastric bypass). Worldwide, gastric bypass and banding have emerged as the most popular procedures.

In the most comprehensive meta-analysis (22 094 patients) it was shown that the mean percentage of excess weight loss (EWL) was 47.5% for gastric banding, 68.2% for gastric bypass, where EWL is the % of weight lost over and above an ideal BMI of 22 kg/m². The difficulty of conducting prospective randomised surgical trials has hindered the uptake of surgical treatment of obesity, but recent cohort data show that the procedures are not only effective in terms of weight loss, but are at least safe in relation to mortality, and results favour improved long term survival compared to medical/behavioural intervention. Although mortality is low, short-term complications and hospitalization are not uncommon after bariatric surgery. However, in the medium- and long-term, the improvement in co-morbidities is impressive. Over 75% of surgically treated patients with diabetes experience resolution of diabetes after gastric bypass surgery; similarly obstructive sleep apnoea and idiopathic intracranial hypertension improve. Finally, quality of life indices improve after surgical intervention.

NICE recommend surgical treatment for those with a BMI>40 kg/m², and for those with a BMI>35 with co-morbidity, after other interventions have been unsuccessful. In summary, bariatric surgery should be considered early in patients where significant weight loss is required to ameliorate obesity-related medical or psychosocial co-morbidity.