Bariatric surgery for morbid obesity

Background: Bariatric surgery is a treatment for severely obese patients. We examined the efficacy of bariatric surgery, addressing three questions: 1) "What is the overall weight reduction following bariatric surgery?" 2) "What complications are associated with bariatric surgery?" 3) "What impact does weight loss have on obesity-related comorbidity?" Methods: Fixed and random effects meta-analyses were used to determine the amount of weight reduction following bariatric surgery. The influence of a variety of co-variates that could affect study results was examined. Information from evidence-based sources was used to explore the impact of weight loss on comorbidities. Results: Meta-analyses results were affected by loss to follow-up, and within-study heterogeneity of variance. Therefore, results were pooled from studies with complete patient follow-up. Meta-analysis of six studies reporting weight loss at 1 year and four studies with mean follow-up of 9 months to 7 years demonstrated BMI reductions of 16.4 kg/m(2) and 13.3 kg/m(2), respectively. Weight reduction following bariatric surgery may be associated with improvements in risk factors for cardiac disease including hypertension, type 2 diabetes and lipid abnormalities, and may decrease the severity of obstructive sleep apnea. Conclusion: Bariatric surgery is appropriate for obese patients (BMI >40 kg/m(2) or greater than or equal to 35 kg/m(2) with obesity-related comorbidity) in whom non-surgical treatment options were unsuccessful. Additional research is needed to examine the long-term benefits of weight loss following bariatric surgery, particularly with respect to obesity-related comorbidities.