EAL

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 this study was to examine the experiences of 63 patients who received laparoscopic adjustable gastric banding (LAGB) between March, 1999 and June, 2001.

Inclusion Criteria:

Inclusion criteria followed the standard ASBS/SAGES guidelines. Participants were required to meet the following criteria:

Body mass index (BMI) 40 or greater, or BMI greater than 35 in association with a co-morbidity
Age 18 to 60 years
Received no prior bariatric surgery
Were not using weight loss medications
Had no history of autoimmune or severe connective tissue disease
Did not regularly use aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs)
Were not participating in another medical or surgical clinical trial.

Exclusion Criteria:

Described under inclusion criteria.

Description of Study Protocol:

Design: Participants were patients who underwent LAGB between March, 1999 and June, 2001. Patients were followed for complications and weight loss measurements for up to three years.
Statistical analysis: All results were given as means ± standard deviation (SD). Statistical analysis methods were not described.

Data Collection Summary:

Timing of Measurements

Measurements were taken pre-operatively and at months six, 12, 24 and 36.

Dependent Variables

Operation time
Length of hospital stay
Weight lost (expressed as excess weight loss or % EWL)
Co-morbidities: diabetes, hypertension and obstructive sleep apnea
Post-surgery complications

No statistical analysis methods were described for dependent variables.

Independent Variables

All patients underwent LAGB.

Control Variables

All patients were placed on a liquid diet for three to seven days prior to surgery
Following surgery, patients followed a three-week full liquid diet, followed by pureed foods and then soft foods. Patients then transitioned to a well-chewed regular diet.

Description of Actual Data Sample:

Initial N: 63 patients (7 males, 56 females)
Attrition (final N): 62
Age: Mean age 40.8 years (range 18 to 60 years)
Ethnicity: Not described
Other relevant demographics: Not described
Anthropometrics: Mean BMI was 48.8kg per m² (range 36.8 - 67.0kg per m²)
Location: State University of New York at Stony Brook, New York, USA.

Summary of Results:

All patients lost weight. Weight loss expressed as excess weight lost (% EWL) increasing with time.

Month	% EWL ± SD	N (Number of patients)
6	27.2±14.2	62
12	38.3±15.6	59
24	46.6±19.5	19
36	53.6±23.8	13

Other Findings

Mean length of surgery decreased from 197.3±72.1 SD minutes for first 10 patients to 120.0±32.7 minutes for last 13 patients
Co-morbidities improved greatly or resolved following LAGB surgery
- 5 of 6 patients greatly improved or resolved diabetes
- 13 of 28 patients improved or resolved hypertension
- 12 of 12 patients resolved obstructive sleep apnea.

Author Conclusion:

The author cites that after additional cases were examined, no gastric slippage, band revisions or explantation occurred in patients six months post-surgery
Additionally, the author has begun to use the pars flaccida dissection approach, as it has shown to reduce the potential for gastric band slippage and band erosion.

Funding Source:

University/Hospital:

State University of New York at Stony Brook

Reviewer Comments:

This study did not describe any statistical analysis methods.

Quality Criteria Checklist: Primary Research
Relevance Questions
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	Yes
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	Yes
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes

Validity Questions
	1.	Was the research question clearly stated?	Yes
1.	Was the research question clearly stated?		Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.3.	Were the target population and setting specified?	Yes
	1.3.	Were the target population and setting specified?	Yes
	2.	Was the selection of study subjects/patients free from bias?	Yes
2.	Was the selection of study subjects/patients free from bias?		Yes
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	Yes
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	Yes
	2.2.	Were criteria applied equally to all study groups?	Yes
	2.2.	Were criteria applied equally to all study groups?	Yes
	2.3.	Were health, demographics, and other characteristics of subjects described?	Yes
	2.3.	Were health, demographics, and other characteristics of subjects described?	Yes
	2.4.	Were the subjects/patients a representative sample of the relevant population?	Yes
	2.4.	Were the subjects/patients a representative sample of the relevant population?	Yes
	3.	Were study groups comparable?	N/A
3.	Were study groups comparable?		N/A
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	N/A
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	N/A
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	No
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	No
	3.4.	If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?	N/A
	3.4.	If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?	N/A
	3.5.	If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)	N/A
	3.5.	If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)	N/A
	3.6.	If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?	N/A
	3.6.	If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?	N/A
	4.	Was method of handling withdrawals described?	???
4.	Was method of handling withdrawals described?		???
	4.1.	Were follow-up methods described and the same for all groups?	Yes
	4.1.	Were follow-up methods described and the same for all groups?	Yes
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	???
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	???
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	???
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	???
	4.4.	Were reasons for withdrawals similar across groups?	???
	4.4.	Were reasons for withdrawals similar across groups?	???
	4.5.	If diagnostic test, was decision to perform reference test not dependent on results of test under study?	N/A
	4.5.	If diagnostic test, was decision to perform reference test not dependent on results of test under study?	N/A
	5.	Was blinding used to prevent introduction of bias?	No
5.	Was blinding used to prevent introduction of bias?		No
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	N/A
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	N/A
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	No
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	No
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	N/A
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	N/A
	5.4.	In case control study, was case definition explicit and case ascertainment not influenced by exposure status?	N/A
	5.4.	In case control study, was case definition explicit and case ascertainment not influenced by exposure status?	N/A
	5.5.	In diagnostic study, were test results blinded to patient history and other test results?	N/A
	5.5.	In diagnostic study, were test results blinded to patient history and other test results?	N/A
	6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?	Yes
6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?		Yes
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	N/A
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	N/A
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	Yes
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	Yes
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	Yes
	6.6.	Were extra or unplanned treatments described?	Yes
	6.6.	Were extra or unplanned treatments described?	Yes
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	Yes
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	Yes
	6.8.	In diagnostic study, were details of test administration and replication sufficient?	N/A
	6.8.	In diagnostic study, were details of test administration and replication sufficient?	N/A
	7.	Were outcomes clearly defined and the measurements valid and reliable?	Yes
7.	Were outcomes clearly defined and the measurements valid and reliable?		Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	Yes
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	Yes
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	Yes
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	Yes
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	Yes
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	Yes
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	Yes
	7.7.	Were the measurements conducted consistently across groups?	Yes
	7.7.	Were the measurements conducted consistently across groups?	Yes
	8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?	Yes
8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?		Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.2.	Were correct statistical tests used and assumptions of test not violated?	N/A
	8.2.	Were correct statistical tests used and assumptions of test not violated?	N/A
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	N/A
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	N/A
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	N/A
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	N/A
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	N/A
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	N/A
	8.6.	Was clinical significance as well as statistical significance reported?	N/A
	8.6.	Was clinical significance as well as statistical significance reported?	N/A
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	N/A
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	N/A
	9.	Are conclusions supported by results with biases and limitations taken into consideration?	???
9.	Are conclusions supported by results with biases and limitations taken into consideration?		???
	9.1.	Is there a discussion of findings?	Yes
	9.1.	Is there a discussion of findings?	Yes
	9.2.	Are biases and study limitations identified and discussed?	No
	9.2.	Are biases and study limitations identified and discussed?	No
	10.	Is bias due to study's funding or sponsorship unlikely?	Yes
10.	Is bias due to study's funding or sponsorship unlikely?		Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes