Context About 5% of the US population is morbidly obese. This disease remains
largely refractory to diet and drug therapy, but generally responds well to
Objective To determine the impact of bariatric surgery on weight loss, operative
mortality outcome, and 4 obesity comorbidities (diabetes, hyperlipidemia,
hypertension, and obstructive sleep apnea).
Data Sources and Study Selection Electronic literature search of MEDLINE, Current Contents, and the Cochrane
Library databases plus manual reference checks of all articles on bariatric
surgery published in the English language between 1990 and 2003. Two levels
of screening were used on 2738 citations.
Data Extraction A total of 136 fully extracted studies, which included 91 overlapping
patient populations (kin studies), were included for a total of 22 094
patients. Nineteen percent of the patients were men and 72.6% were women,
with a mean age of 39 years (range, 16-64 years). Sex was not reported for
1537 patients (8%). The baseline mean body mass index for 16 944 patients
was 46.9 (range, 32.3-68.8).
Data Synthesis A random effects model was used in the meta-analysis. The mean (95%
confidence interval) percentage of excess weight loss was 61.2% (58.1%-64.4%)
for all patients; 47.5% (40.7%-54.2%) for patients who underwent gastric banding;
61.6% (56.7%-66.5%), gastric bypass; 68.2% (61.5%-74.8%), gastroplasty; and
70.1% (66.3%-73.9%), biliopancreatic diversion or duodenal switch. Operative
mortality (≤30 days) in the extracted studies was 0.1% for the purely restrictive
procedures, 0.5% for gastric bypass, and 1.1% for biliopancreatic diversion
or duodenal switch. Diabetes was completely resolved in 76.8% of patients
and resolved or improved in 86.0%. Hyperlipidemia improved in 70% or more
of patients. Hypertension was resolved in 61.7% of patients and resolved or
improved in 78.5%. Obstructive sleep apnea was resolved in 85.7% of patients
and was resolved or improved in 83.6% of patients.
Conclusions Effective weight loss was achieved in morbidly obese patients after
undergoing bariatric surgery. A substantial majority of patients with diabetes,
hyperlipidemia, hypertension, and obstructive sleep apnea experienced complete
resolution or improvement.