dsfacts logo

Get the Facts on Duodenal Switch.

Required Preop Weight Loss

Studies demonstrating that required preop weight loss or wait time for surgery is not a predictor of postop bariatric surgery weight loss success.

Preoperative weight gain does not predict failure of weight loss or co-morbidity resolution of laparoscopic Roux-en-Y gastric bypass for morbid obesity.
Harnisch et al. May 2008
PubMed Abstract

BACKGROUND: Success with preoperative weight loss (PWL) is often mandated by the bariatric team to assess patient compliance and has been suggested to correlate with improved postoperative weight loss outcomes.

METHODS: We performed a retrospective analysis of 1629 consecutive patients undergoing laparoscopic Roux-en-Y gastric bypass at Duke University Medical Center. Patients with a preoperative weight gain (PWG) or loss of > or =10 lb were compared. Patients with <12 months of follow-up were excluded.

RESULTS: We found no difference between the 2 groups (PWG, n = 115, PWL, n = 88) with regard to age, gender, race, preoperative body mass index, presence of co-morbidities, or interval between the initial program-entry weight and surgery (149 versus 141 d). No difference was found in the percentage of excess weight loss (EWL) at 12 months, when calculated using the patient's immediate preoperative weight (PWG group, 63.5% EWL versus PWL group, 63.9% EWL, P = NS). If the %EWL was calculated using the initial program-entry weight, the PWL did confer a transient postoperative weight loss advantage; however, this did not persist past 24 months postoperatively. At both 12 and 24 months, the resolution rates of diabetes (82% versus 83% at 2 yr; P = NS), hypertension (48% versus 42% at 2 yr, P = NS), and continuous positive airway pressure discontinuation (87% versus 87% at 1 yr, P = NS) were equivalent. No differences in perioperative complications or conversion rates were detected. The operative time was slightly longer for the PWG group (119.7 versus 104.9 min, P = .02).

CONCLUSION: The results of our study have shown that weight loss before laparoscopic Roux-en-Y gastric bypass is not mandatory and might deter patients from considering weight loss surgery. Laparoscopic Roux-en-Y gastric bypass can be performed safely with equivalent co-morbidity resolution and %EWL regardless of PWG or PWL.

Does preoperative weight loss predict success following surgery for morbid obesity?
Mrad et al. May 2008
PubMed Abstract

BACKGROUND: We analyzed preoperative weight loss as a predictor of postoperative success in patients after bariatric surgery.

METHODS: Data were obtained from a retrospective chart review of 562 patients in a multidisciplinary obesity clinic.

RESULTS: One hundred forty-six patients met the inclusion criteria (23 men and 123 women). The mean age was 39.5 years, and the mean body mass index (BMI) was 52.6 kg/m(2). Comorbid disease includes diabetes (15.7%), hypertension (30.8%), mental illness (38.4%), and musculoskeletal disease (56.8%). Procedures performed were 16 vertical band gastroplasties, 43 open gastric bypasses, 52 laparoscopic gastric bypasses, and 35 laparoscopic adjustable gastric bands. Preoperative weight change was as follows: 31 patients gained weight (21.2%), 56 patients lost weight (38.3%), and 59 patients maintained their weight (40.4%). Postoperative weight loss was not influenced by preoperative weight change among women. However, men who gained weight preoperatively had significantly worse outcomes.

CONCLUSIONS: Patients may achieve satisfactory early postoperative outcomes despite inconsistent or marginal preoperative weight change.

Evaluating preoperative weight loss, binge eating disorder, and sexual abuse history on Roux-en-Y gastric bypass outcome.
Fujioka et al. Mar 2008
PubMed Abstract

BACKGROUND: Roux-en-Y gastric bypass patients often undergo preoperative dieting and psychological assessment before surgery. We examined preoperative weight loss, binge eating disorder (BED), and sexual abuse history and the interactions of these predictors to determine whether a cautionary approach to Roux-en-Y gastric bypass is warranted.

METHODS: Consecutive subjects undergoing Roux-en-Y gastric bypass at our institution from January 1997 to December 2002 were reviewed. The postoperative excess weight loss (EWL) at 1, 3, 6, 12, 18, and 24 months and the perioperative complications were measured. EWL was compared at 12 and 24 months postoperatively in the categories of the presence/absence of preoperative weight loss, BED, and sexual abuse history. The perioperative complications were examined in the preoperative weight change groups.

RESULTS: Of 154 patients, 121 were included. No significant difference in EWL or perioperative complications was observed between those who lost or gained weight preoperatively. Of the 121 patients, 32% and 17% reported a history of BED and sexual abuse, respectively. No statistically significant difference was observed in the EWL between those with and without BED at 12 and 24 months postoperatively. The EWL in those with and without a sexual abuse history at 12 and 24 months was 57.67% and 66.32% (P <.05) and 64.40% and 70.97% (P = NS). No statistically significant interaction between EWL and sexual abuse*BED/sexual abuse*preoperative weight loss was observed.

CONCLUSION: Only sexual abuse history at postoperative month 12 had a negative effect on EWL. Otherwise, physicians can expect to see successful EWL in these subjects up to 24 months postoperatively. We recommend that additional investigation be done of those with BED and a sexual abuse history.

Patients who are delayed from undergoing bariatric surgery do not have improved weight loss.
Madan et al. Mar 2008
PubMed Abstract

BACKGROUND: Many patients have a prolonged wait time between initial surgeon visit and actual surgery day. Whereas there are various reasons for this, few have examined if patient wait time for bariatric surgery has any affect on weight loss. This investigation studies the hypothesis that patients who wait longer for bariatric surgery do not have improved weight loss over those with shorter wait times.

METHODS: All patients in a private academic practice who underwent laparoscopic gastric bypass over a 6-month period were included in this study. The time from initial office visit to actual surgery date was calculated to be wait time (WT). Reasons for short or long WT were not investigated. The relationship between WT and percentage excess body weight loss (%EBWL) was examined. In addition, patients whose WT was greater than 6 months (WT > 6) were compared to those less than 6 months (WT < 6). Pearson's correlation coefficients and two-tailed Mann-Whitney tests were used as appropriate.

RESULTS: There were 104 patients with 99 patients who had a >1 year follow-up. WT did not correlate with %EBWL (r = 0.09, p = 0.37). There was no difference in %EBWL in the WT > 6 group versus the WT < 6 group (73 vs. 70%; p = NS). Patients who had <50% EBWL waited an average of 281 versus 254 days for those who have >50% EBWL (p = NS).

CONCLUSIONS: Patients who wait longer before having bariatric surgery do not show improved weight loss. Weight loss success was not related to wait time. These results suggest that prolonged mandatory weight times are not an effective method for improving bariatric surgery weight loss outcomes. Mandatory delays for bariatric surgery should not be required, as they have no scientific merit.

Now that you know about Required Preop Weight Loss
NEXT: More Articles