NCBS: Weight Loss and Weight Regain Expected After Procedure (2009)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

The purpose of the research is to assess the efficacy and the safety of laparoscopic adjustable gastric banding (LAGB) as a therapeutic strategy and to compare the Swedish adjustable gastric band (SAGB) and the Lap-Band (LB) in terms of weight loss, co-morbidity improvement and complications.

Inclusion Criteria:
  • Studies of any design with more than 10 patients who had undergone SAGB or LB
  • Studies with more than 30-day efficacy or safety outcomes
  • Bands must be placed laparoscopically in more than 85% of patients
  • Follow-up data reported in 50% of the population at the latest point.

 

Exclusion Criteria:
  • Studies reporting less than 10 patients
  • Studies with no outcome data reported.
Description of Study Protocol:

Recruitment

All studies of any design on more than 10 patients who had undergone SAGB or LB implantation and reporting extractable outcome data.

Design

Systematic review of published medical studies and meta-analyses that compare the SAGB and LB outcomes.

Statistical Analysis

Meta-analytic pooling of the SAGB and LB results. The random effects model was used on the efficacy outcome. Bayesian meta-analyses were conducted for selected outcomes. Cochrane's Q statistics assessed the heterogeneity.

 

Data Collection Summary:

Timing of Measurements

  • Less than two years
  • Two to three years
  • More than three years.

Dependent Variables

  • Weight (measured as weighted mean and mean change)
  • BMI (measured as weighted mean and mean change)
  • Percentage excess weight loss (EWL) ( measured as weighted mean and mean change).

Independent Variables

  • Co-morbid disease: Type 2 diabetes and hypertension
  • Complications: Slippage or migration, pouch dilation.

 

 

Description of Actual Data Sample:

Initial N

129 studies (N=28,980).

Attrition (final N)

  • Not applicable to systematic review
  • Studies reporting follow-up: 44 studies, less than two years; 36 studies, two to three years; 36 studies, more than years; 13 studies, did not report follow-up. 

Age

Swedish adjustable gastric banding (SAGB) and laparoscopic banding (LB) groups: 39.1 to 40.2 years.

Other Relevant Demographics

  • Percentage of women: 79.2% and 82.5% (SAGB and LB, respectively)
  • Co-morbidities: 24% and 37% hypertensive (SAGB and LB, respectively).

Anthropometrics

BMI: 43.8kg/m2 and 45.3kg/m2.

Location

Europe, North America, Australia, Egypt, Israel, Saudi Arabia and Singapore.

 

Summary of Results:

 

Weight Loss

Variables

SAGB

(N)

 SAGB

Mean Change, 95% CI (kg)

(N) Lap-Band

LB

Mean Change, 95% CI (kg)

Statistical Significance of Group Difference

Weight (kg)

Follow-up with more than 50% pts

Two years

Three years

 

 

 

 1,235

387

323

 

 

-40.35 (-48.91, -31.79)

-44.98 (-57.18, -32.79)

 -49.89 (-64.18, -35.61)

 

 2,436

803

501

 

-30.14 (-34.54, -25.74)

-34.17 (-39.71, -28.64)

-37.25 (-50.20,  -24.31)

 

 P<0.001

P<0.001

P<0.001

BMI Reduction

Follow-up with more than 50% pts

Two years

Three years

 

 

2,459

2,164

1,560

 

-12.30 (-14.48, -10.13)

-13.69 (-16.94, -10.44)

-11.99 (-15.20, -8.77)

 

 8,217

4,275

4,495

 

-10.22(-11.08, -9.37)

-11.32 (-12.10, -10.54)

-11.81 (-13.16, -10.47)

 

P<0.001

P<0.001

P<0.001

%EWL

Follow-up with more than 50% pts

Two  years

Three years

 

 

2,221

1,657

1,560

 

55.62 (50.04,61.21)

49.98 (45.86, 54.10)

56.36 (48.14, 64.58)

 

 6,251

3,540

1,659

 

43.7 (39.98, 47.15)

48.14(43.26, 53.01)

50.20 (43.36, 57.04)

 

P<0.001

 P<0.001

P<0.001

  

Resolution of Coborbid Conditions after Gastric Banding
Co-morbid Condition

SAGB

(N)

SAGB

Mean (95% CI)

LB

(N)

LB

Mean (95% CI)

Significance
Diabetes Resolved  101  61.45 (52.11, 70.78)  249  60.29 (44.75, 75.83) P<0.001
Hypertension Resolved  228  62.95 (41.18, 84.72)  488  43.58 (30.21, 56.95) P<0.001

  

Author Conclusion:

Both bands consistently evidenced statistically significant and durable, safe weight loss at three years. The resolution of diabetes and hypertension was significant for both devices and appeared to parallel weight loss at two years.

 

Funding Source:
Industry:
Ethicon Endo-Surgery
Other:
Reviewer Comments:

 

 

 

Quality Criteria Checklist: Review Articles
Relevance Questions
  1. Will the answer if true, have a direct bearing on the health of patients? Yes
  2. Is the outcome or topic something that patients/clients/population groups would care about? Yes
  3. Is the problem addressed in the review one that is relevant to dietetics practice? Yes
  4. Will the information, if true, require a change in practice? Yes
 
Validity Questions
  1. Was the question for the review clearly focused and appropriate? Yes
  2. Was the search strategy used to locate relevant studies comprehensive? Were the databases searched and the search termsused described? Yes
  3. Were explicit methods used to select studies to include in the review? Were inclusion/exclusion criteria specified andappropriate? Wereselectionmethods unbiased? Yes
  4. Was there an appraisal of the quality and validity of studies included in the review? Were appraisal methodsspecified,appropriate, andreproducible? Yes
  5. Were specific treatments/interventions/exposures described? Were treatments similar enough to be combined? Yes
  6. Was the outcome of interest clearly indicated? Were other potential harms and benefits considered? Yes
  7. Were processes for data abstraction, synthesis, and analysis described? Were they applied consistently acrossstudies and groups? Was thereappropriate use of qualitative and/or quantitative synthesis? Was variation in findings among studies analyzed? Were heterogeneity issued considered? If data from studies were aggregated for meta-analysis, was the procedure described? Yes
  8. Are the results clearly presented in narrative and/or quantitative terms? If summary statistics are used, are levels ofsignificance and/or confidence intervals included? Yes
  9. Are conclusions supported by results with biases and limitations taken into consideration? Are limitations ofthe review identified anddiscussed? Yes
  10. Was bias due to the review's funding or sponsorship unlikely? Yes