on bypass surgery versus control groups, showed a reduction of mortality of 40% and 28%.
Those of the 28% had for a control group traditional treatment of diet (which affected weight only 2%)
Effects of Bariatric Surgery on Mortality in Swedish Obese Subjects
Lars Sjöström, M.D., Ph.D., Kristina Narbro, Ph.D., C. David Sjöström, M.D., Ph.D.,
Kristjan Karason, M.D., Ph.D., Bo Larsson, M.D., Ph.D., Hans Wedel, Ph.D., Ted Lystig, Ph.D., Marianne Sullivan, Ph.D., Claude
Bouchard, Ph.D., Björn Carlsson, M.D., Ph.D., Calle Bengtsson, M.D., Ph.D., Sven Dahlgren, M.D., Ph.D., Anders Gummesson,
M.D., Peter Jacobson, M.D., Ph.D., Jan Karlsson, Ph.D., Anna-Karin Lindroos, Ph.D., Hans Lönroth, M.D., Ph.D., Ingmar Näslund,
M.D., Ph.D., Torsten Olbers, M.D., Ph.D., Kaj Stenlöf, M.D., Ph.D., Jarl Torgerson, M.D., Ph.D., Göran Ågren, M.D., Lena M.S.
Carlsson, M.D., Ph.D., for the Swedish Obese Subjects Study
Background Obesity is associated
with increased mortality. Weight loss improves cardiovascular risk factors, but no prospective interventional
studies have reported whether weight loss decreases overall mortality. In fact, many observational studies suggest
that weight reduction is associated with increased mortality.
Methods The prospective, controlled
Swedish Obese Subjects study involved 4047 obese subjects. Of these subjects, 2010 underwent bariatric
surgery (surgery group) and 2037 received conventional treatment (matched control group). We report on overall
mortality during an average of 10.9 years of follow-up. At the time of the analysis (November 1, 2005), vital status was known for all but three subjects (follow-up rate, 99.9%).
Results The average weight change in control subjects was less than ±2% during the period of up
to 15 years during which weights were recorded. Maximum weight losses in
the surgical subgroups were observed after 1 to 2 years: gastric bypass, 32%; vertical-banded gastroplasty,
25%; and banding, 20%. After 10 years, the weight losses from
baseline were stabilized at 25%, 16%, and 14%, respectively. There were
129 deaths in the control group and 101 deaths in the surgery group. The unadjusted overall hazard ratio
was 0.76 in the surgery group (P=0.04), as compared with the control group, and the hazard ratio adjusted
for sex, age, and risk factors was 0.71 (P=0.01). The most common
causes of death were myocardial infarction (control group, 25 subjects; surgery group, 13 subjects) and cancer
(control group, 47; surgery group, 29).
Conclusions Bariatric surgery
for severe obesity is associated with long-term weight loss and decreased overall mortality.
From the Institutes of Medicine (L.S., K.N., K.K., T.L., M.S.,
B.C., A.G., P.J., J.K., K.S., L.M.S.C.), Anesthesiology (C.D.S., B.L.), Surgery (H.L., T.O.), and Primary Health Care (C.
Bengtsson), Sahlgrenska Academy, Gothenburg University, Gothenburg; Nordic School of Public Health, Gothenburg (H.W.); Börjegatan
10B, Uppsala (S.D.); Department of Surgery, University Hospital, Örebro (I.N., G.A.); and Department of Medicine, Northern
Älvsborg Hospital, Trollhättan (J.T.) — all in Sweden; Pennington Biomedical Research Center, Louisiana State University
System, Baton Rouge (L.S., C. Bouchard); and Medical Research Council Human Nutrition Research, Elsie Widdowson Laboratory,
Cambridge University, Cambridge, United Kingdom (A.-K.L.).
Address reprint requests to Dr. L. Sjöström at the Swedish Obese
Subjects Secretariat, Vita stråket 15, Sahlgrenska University Hospital, S-413 45 Gothenburg, Sweden,
The New England Journal of Medicine, Volume 357:753-761 August
23, 2007, Number 8
Long-Term Mortality after Gastric Bypass Surgery
Ted D. Adams, Ph.D., M.P.H., Richard E. Gress, M.A., Sherman C. Smith, M.D.,
R. Chad Halverson, M.D., Steven C. Simper, M.D., Wayne D. Rosamond, Ph.D., Michael J. LaMonte, Ph.D., M.P.H., Antoinette M.
Stroup, Ph.D., and Steven C. Hunt, Ph.D.
Background Although gastric
bypass surgery accounts for 80% of bariatric surgery in the United States, only limited long-term
data are available on mortality among patients who have undergone this procedure as compared with severely
obese persons from a general population.
Methods In this retrospective
cohort study, we determined the long-term mortality (from 1984 to 2002) among 9949 patients who had
undergone gastric bypass surgery and 9628 severely obese persons who applied for driver's licenses. From these
subjects, 7925 surgical patients and 7925 severely obese control subjects were matched for age, sex,
and body-mass index. We determined the rates of death from any cause and from specific causes with the
use of the National Death Index.
Results During a mean follow-up
of 7.1 years, adjusted long-term
mortality from any cause in the surgery group decreased by 40%, as compared with that in the control group (37.6 vs. 57.1 deaths per 10,000 person-years, P<0.001); cause-specific mortality in the
surgery group decreased by 56% for coronary artery disease (2.6 vs. 5.9 per 10,000 person-years, P=0.006),
by 92% for diabetes (0.4 vs. 3.4 per 10,000 person-years, P=0.005), and by 60% for cancer (5.5 vs. 13.3 per 10,000 person-years, P<0.001).
However, rates of death not caused by disease, such as accidents and suicide, were 58% higher in the
surgery group than in the control group (11.1 vs. 6.4 per 10,000 person-years, P=0.04).
Conclusions Long-term total
mortality after gastric bypass surgery was significantly reduced, particularly deaths from diabetes, heart
disease, and cancer. However, the rate of death from causes other than disease was higher in the surgery group
than in the control group.
From the Cardiovascular Genetics Division, University of Utah
School of Medicine (T.D.A., R.E.G., S.C.H.); Intermountain Health and Fitness Institute, LDS Hospital (T.D.A.); Rocky Mountain
Associated Physicians (S.C. Smith, R.C.H., S.C. Simper); and Utah Cancer Registry, University of Utah (A.M.S.) — all
in Salt Lake City; School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill (W.D.R.); and the Department
of Social and Preventive Medicine, University at Buffalo, Buffalo, NY (M.J.L.).
Address reprint requests to Dr. Adams at Cardiovascular Genetics,
University of Utah School of Medicine, 420 Chipeta Way, Rm. 1160, Salt Lake City, UT