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The outcomes information and comments on this page are based on unselected, consecutive patients from Dr. Callery's bariatric surgery practice.

  • Each Green Diamond represents one patient at time of last follow-up.
  • The blue triangles show the average at that time.
  • Each patient starts at 100% overweight. The "0%" mark indicates ideal weight based on life insurance tables. The "0%" value is thus an approximation.

This graph shows the weight loss results for the patients from Dr. Callery's practice. Each patient starts out at 100% overweight. If everyone were to lose all of her/his excess weight, the green diamonds would all drop to 0% on the Y-axis. If patients had not had surgery they probably would have gained weight and might be at 110% or 120% over time.

This graph shows two important results. First, as a group, patients lose a great deal of weight over time, and tend to keep much of it off. For these patients, average excess weight loss at 2 years is 80%, at 4 years is 64%, and 5 years 65%. We do not have enough data to calculate a meaningful average beyond 5 years. Second, there is a great deal of variation among patients. Some drop to a normal weight while a few will keep off little of their excess weight. A few patients are underweight, but this is usually not a major problem.

While some of this variation of weight loss may be due to the surgery, interviews with patients suggest that much of the variation is due to variations in dietary and exercise patterns. People who do well tend to avoid snacks, eat healthy types of food, and be active. Those patients who tend to regain weight tend to be those who don't change their eating and exercise patterns, or those that return to snacking behaviors. There may be a genetic basis for various patient's response to surgery, but this hasn't been worked out. There is no reliable psychological or medical test that can accurately predict who will do well and who will only lose a small amount of weight.

Most studies in the medical literature suggest that patients lose about 2/3 to 3/4 of their excess weight over the first two years. Longer term studies have shown that on average patients keep off at least 50 to 65% of the excess weight over 5 to 15 years. There is no data available beyond 15 years. Thus there is some weight regain that occurs over time after the first two years, but patients are as a group much better off from a weight and health standpoint even long after surgery.

Related Questions and Answers from Thinner Times Forum

Related Medical Journals:

Effects of bariatric surgery on mortality in Swedish obese subjects.

N Engl J Med. 2007 Aug 23;357(8):741-52.

Sjöström L, et. al

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. Copyright 2007 Massachusetts Medical Society.

Laparoscopic adjustable gastric banding versus Roux-en-Y gastric bypass: 5-year results of a prospective randomized trial.

Surg Obes Relat Dis. 2007 Mar-Apr;3(2):127-32; discussion 132-3. Epub 2007 Feb 27. Links

Angrisani L, Lorenzo M, Borrelli V.

S. Giovanni Bosco Hospital, Naples, Italy. This e-mail address is being protected from spambots. You need JavaScript enabled to view it

BACKGROUND: To perform a prospective, randomized comparison of laparoscopic adjustable gastric banding (LAGB) and laparoscopic Roux-en-Y gastric bypass (LRYGB). METHODS: LAGB, using the pars flaccida technique, and standard LRYGB were performed. From January 2000 to November 2000, 51 patients (mean age 34.0 +/- 8.9 years, range 20-49) were randomly allocated to undergo either LAGB (n = 27, 5 men and 22 women, mean age 33.3 years, mean weight 120 kg, mean body mass index [BMI] 43.4 kg/m(2); percentage of excess weight loss 83.8%) or LRYGB (n = 24, 4 men and 20 women, mean age 34.7, mean weight 120 kg, mean BMI 43.8 kg/m(2), percentage of excess weight loss 83.3). Data on the operative time, complications, reoperations with hospital stay, weight, BMI, percentage of excess weight loss, and co-morbidities were collected yearly. Failure was considered a BMI of >35 at 5 years postoperatively. The data were analyzed using Student's t test and Fisher's exact test, with P <.05 considered significant. RESULTS: The mean operative time was 60 +/- 20 minutes for the LAGB group and 220 +/- 100 minutes for the LRYGB group (P <.001). One patient in the LAGB group was lost to follow-up. No patient died. Conversion to laparotomy was performed in 1 (4.2%) of 24 LRYGB patients because of a posterior leak of the gastrojejunal anastomosis. Reoperations were required in 4 (15.2%) of 26 LAGB patients, 2 because of gastric pouch dilation and 2 because of unsatisfactory weight loss. One of these patients required conversion to biliopancreatic diversion; the remaining 3 patients were on the waiting list for LRYGB. Reoperations were required in 3 (12.5%) of the 24 LRYGB patients, and each was because of a potentially lethal complication. No LAGB patient required reoperation because of an early complication. Of the 27 LAGB patients, 3 had hypertension and 1 had sleep apnea. Of the 24 LRYGB patients, 2 had hyperlipemia, 1 had hypertension, and 1 had type 2 diabetes. Five years after surgery, the diabetes, sleep apnea, and hyperlipemia had resolved. At the 5-year (range 60-66 months) follow-up visit, the LRYGB patients had significantly lower weight and BMI and a greater percentage of excess weight loss than did the LAGB patients. Weight loss failure (BMI >35 kg/m(2) at 5 yr) was observed in 9 (34.6%) of 26 LAGB patients and in 1 (4.2%) of 24 LRYGB patients (P <.001). Of the 26 patients in the LAGB group and 24 in the LRYGB group, 3 (11.5%) and 15 (62.5%) had a BMI of <30 kg/m(2), respectively (P <.001). CONCLUSION: The results of our study have shown that LRYGB results in better weight loss and a reduced number of failures compared with LAGB, despite the significantly longer operative time and life-threatening complications.

Surgery decreases long-term mortality, morbidity, and health care use in morbidly obese patients.

Christou NV, Sampalis JS, Liberman M, Look D, Auger S, McLean AP, MacLean LD

.Ann Surg. 2004 Sep;240(3):416-23; discussion 423-4.

Section of Bariatric Surgery, Division of General Surgery, Department of Surgery, McGill University, Montreal, Quebec, Canada. This e-mail address is being protected from spambots. You need JavaScript enabled to view it

OBJECTIVE: This study tested the hypothesis that weight-reduction (bariatric) surgery reduces long-term mortality in morbidly obese patients. BACKGROUND: Obesity is a significant cause of morbidity and mortality. The impact of surgically induced, long-term weight loss on this mortality is unknown. METHODS: We used an observational 2-cohort study. The treatment cohort (n = 1035) included patients having undergone bariatric surgery at the McGill University Health Centre between 1986 and 2002. The control group (n = 5746) included age- and gender-matched severely obese patients who had not undergone weight-reduction surgery identified from the Quebec provincial health insurance database. Subjects with medical conditions (other then morbid obesity) at cohort-inception into the study were excluded. The cohorts were followed for a maximum of 5 years from inception. RESULTS: The cohorts were well matched for age, gender, and duration of follow-up. Bariatric surgery resulted in significant reduction in mean percent excess weight loss (67.1%, P < 0.001). Bariatric surgery patients had significant risk reductions for developing cardiovascular, cancer, endocrine, infectious, psychiatric, and mental disorders compared with controls, with the exception of hematologic (no difference) and digestive diseases (increased rates in the bariatric cohort). The mortality rate in the bariatric surgery cohort was 0.68% compared with 6.17% in controls (relative risk 0.11, 95% confidence interval 0.04-0.27), which translates to a reduction in the relative risk of death by 89%. CONCLUSIONS: This study shows that weight-loss surgery significantly decreases overall mortality as well as the development of new health-related conditions in morbidly obese patients.

Impact of gastric bypass operation on survival: a population-based analysis.

J Am Coll Surg. 2004 Oct;199(4):543-51.

Flum DR, Dellinger EP.

Department of Surgery, University of Washington, Seattle, WA 98195-7183, USA.

BACKGROUND: Bariatric procedures are increasingly performed but their impact on survival is unknown. STUDY DESIGN: We evaluated short- and longterm mortality rates of patients undergoing gastric bypass on a population level compared with a nonoperated cohort of patients with morbid obesity in a retrospective study, using the Washington State Comprehensive Hospital Abstract Reporting System database and the Vital Statistics database. The study included all patients (age 18 to 65 years) from 1987 to 2001 who underwent gastric bypass with ICD-9 diagnostic codes for obesity. The comparator group included patients of similar age with a diagnosis of obesity or morbid obesity who did not have a bariatric procedure. Survival analysis was used to determine the association of surgeon experience on 30-day mortality and of the procedure on survival while controlling for age, gender, and comorbidity index. RESULTS: Of the 66,109 obese patients we evaluated, 3,328 had a bariatric procedure. Incidence of the procedure increased from 0.7 to 10.6 per 100,000 from 1987 to 2001, with a 2.5-fold increase in incidence rate of the procedure in the years after 1996 (incidence rate ratio, 2.5; 95% CI, 2.4 to 2.7). Thirty-day mortality was 1.9% and was associated with surgical inexperience. Within the surgeon's first 19 procedures the odds of death within 30 days were 4.7 times higher (95% CI, 1.2 to 18.2) than at later points in a surgeon's case order. At 15 years followup, 16.3% of nonoperated patients had died as compared with 11.8% of patients who had the bariatric procedure. When survival was compared beginning 1 year after the procedure, the adjusted hazard for death was 33% lower than that of nonoperated patients (hazard ratio 0.67; 95% CI, 0.54 to 0.85). CONCLUSIONS: Thirty-day mortality after gastric bypass is higher than previously reported and closely linked to surgeon inexperience. A modest overall survival benefit was associated with the procedure but a marked survival advantage was noted for patients who survive to the first postoperative year.

Bariatric surgery: a systematic review and meta-analysis

.JAMA. 2004 Oct 13;292(14):1724-37.

Buchwald H, Avidor Y, Braunwald E, Jensen MD, Pories W, Fahrbach K, Schoelles K.

Department of Surgery, University of Minnesota, Minneapolis 55455, USA. This e-mail address is being protected from spambots. You need JavaScript enabled to view it

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 bariatric surgery. 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 (< or =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.

Obesity, Pharmacological and Surgical Treatment

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