The prevalence of obesity and outcomes of bariatric surgery are well established.
However, analyses of the surgery impact have not been updated and comprehensively
investigated since 2003.
To examine the effectiveness and risks of bariatric surgery using up-to-date, comprehensive
data and appropriate meta-analytic techniques.
Literature searches of Medline, Embase, Scopus, Current Contents, Cochrane Library,
and Clinicaltrials.gov between 2003 and 2012 were performed.
Exclusion criteria included publication of abstracts only, case reports, letters,
comments, or reviews; animal studies; languages other than English; duplicate studies;
no surgical intervention; and no population of interest. Inclusion criteria were a
report of surgical procedure performed and at least 1 outcome of interest resulting
from the studied surgery was reported: comorbidities, mortality, complications, reoperations,
or weight loss. Of the 25,060 initially identified articles, 24,023 studies met the
exclusion criteria, and 259 met the inclusion criteria.
A review protocol was followed throughout. Three reviewers independently reviewed
studies, abstracted data, and resolved disagreements by consensus. Studies were evaluated
for quality.
Mortality, complications, reoperations, weight loss, and remission of obesity-related
diseases.
A total of 164 studies were included (37 randomized clinical trials and 127 observational
studies). Analyses included 161,756 patients with a mean age of 44.56 years and body
mass index of 45.62. We conducted random-effects and fixed-effect meta-analyses and
meta-regression. In randomized clinical trials, the mortality rate within 30 days
was 0.08% (95% CI, 0.01%-0.24%); the mortality rate after 30 days was 0.31% (95% CI,
0.01%-0.75%). Body mass index loss at 5 years postsurgery was 12 to 17. The complication
rate was 17% (95% CI, 11%-23%), and the reoperation rate was 7% (95% CI, 3%-12%).
Gastric bypass was more effective in weight loss but associated with more complications.
Adjustable gastric banding had lower mortality and complication rates; yet, the reoperation
rate was higher and weight loss was less substantial than gastric bypass. Sleeve gastrectomy
appeared to be more effective in weight loss than adjustable gastric banding and comparable
with gastric bypass.
Bariatric surgery provides substantial and sustained effects on weight loss and ameliorates
obesity-attributable comorbidities in the majority of bariatric patients, although
risks of complication, reoperation, and death exist. Death rates were lower than those
reported in previous meta-analyses.