MNT: RDN in Medical Team (2015)

- Underwent laparoscopic adjustable gastric banding (LABG) between January 2011 and July 2007
- Qualified for surgery according to standards defined by the 1991 NIH Consensus Conference Statement of Gastrointestinal Surgery for Severe Obesity.
Recruitment
Recruited from physicians' offices.
Design
- Data was collected prospectively for 838 consecutive morbidly obese patients who underweight LAGB between January 2001 and July 2007
- Patients were followed by a multi-disciplinary team consisting of a surgeon, physician, dietitian and exercise consultant, all of whom were involved in the process of data collection and evaluation of outcomes
- Follow-up included monthly visits with a member of the multi-disciplinary team for the first six months, at approximately nine months and 12 months and then biannually or as required
- Comorbidity and and QoL data after weight loss with gastric banding was collected and evaluated.
Blinding Used
None.
Intervention
Swedish adjustable gastric band placement.
Statistical Analysis
- Two-sided student's T-test was used to test significant differences between two samples of quantitative variables
- Analysis of variance (ANOVA) was used to test for differences in more than two groups
- Leven's test to determine homogeneity of variance between groups
- P<0.05 was considered statistically significant.
Timing of Measurements
- Fasting blood sugar levels, HbA1c and lipid concentrations were collected pre-operatively and follow-up values were obtained from the patient's treating endocrinologist or primary care physician or as part of the routine laboratory measurements performed at the clinic
- Number, dose and frequency of all hypoglycemic and insulin requirements, anti-hypertensive, lipid-lowering, asthma, analgesics, anti-reflux and anti-depressant medications pre-operatively and post-operatively assessed at each follow-up visit in all patients with greater than six months of follow-up
- Improvement and resolution of comorbid illness identified by dose reduction in medication with improvement in specific laboratory values and evaluated throughout the study
- Weight evaluated at each follow-up time-point using the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) and Beck Depression Inventory II (BDI-II)
- Quality of life perception and depressive mood were identified at baseline and during follow-up visits.
Dependent Variables
- Improvement in comorbid conditions
- Resolution of comorbid conditions
- Weight change
- BMI
- Percentage of excess weight loss (EWL)
- Quality of life
- Depressive mood.
Independent Variables
Gastric banding using the Swedish Adjustable Gastric Band (SABG).Control Variables
- Age
- Gender
- Height.
Initial N
838 patients (159 males, 679 females).
Attrition (Final N)
175 patients matured to 36-month follow-up.
Age
44±8 years.
Ethnicity
- White: 97.1%
- Indian/Chinese: 1.4%
- Aboriginal: 0.2%
- Hispanic: 1.0%
- Pacific Island/Maori: 0.2%.
Other Relevant Demographics
None.
Anthropometrics
Baseline
- Height: 168±9cm
- Absolute weight: 122±25kg
- Ideal body weight: 63±7kg
- Excess body weight: 60±39kg
- BMI: 44±8 kg/m2.
Location
Australia.
Key Findings
- In the total consecutive group of patients, BMI decreased from 44±8kg/m2 to 32±7kg/m2 at 24 months and 32.7±7kg/m2 at 36 months (P<0.001). Percentage EWL in the same intervals was 52±16% (P<0.001) and 54±23% (P<0.001).
- For the entire cohort of 545 patients with comorbid illnesses, after a median follow-up of 13 months, precentage EWL was 26±17%, with a change in BMI of 5.0kg/m2 and an absolute weight loss of 15±8kg
- Of the 545 patients with comorbid illnesses under current review, weight loss was associated with comorbid illness improvement or resolution relative to baseline in all illnesses studied
- Pre-operatively, QoL scores in the eight domains were significantly lower in comparison with community norms, but after a median follow-up of 13 months, all eight domain scores increased significantly to within the range of QoL of individuals in the normal community
- Pre-operatively, 342 patients completed the BDI-II with a mean score of 17.3±10, indicating mild to moderate levels of depressive mood. After surgery, these patients experienced a significant fall in their BDI-II depression scores to a score within the normal range of 7.2±6 (P<0.001).
Variables |
Six Months |
12 Months |
24 Months |
36 Months N=175 |
Absolute Weight, kg |
103±20 |
94±19 |
90±16 |
90±19 |
BMI, kg/m2 |
37±7 |
33±6 |
32±5 |
32±7 |
Percentage EWL |
32±4* |
47±15* |
52±16* |
54±23* |
* P<0.001.
Resolution or improvement of Comorbidities at a Median Follow-Up of 13 Months
Range, six months to 36 months
Comorbidity |
Percentage Resolution or Improvement |
T2DM |
79% |
IGT/insulin Resistance |
69% |
Metabolic Syndrome |
78% |
Hypertension | 67% |
Dyslipidemia | 66% |
GERD | 69% |
Asthma | 57% |
Arthritis/Joint Pain | 70% |
PCOS | 48% |
Depression | 57% |
- LAGB using the SAGB is an effective method for achieving and maintaining substantial weight loss in the majority of morbidly obese patients undergoing bariatric surgery
- After gastric banding, morbidly obese patients experienced marked weight loss in addition to a reduction of the major comorbid conditions that not only threaten their lives but significantly impair their daily QoL.
Industry: |
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Quality Criteria Checklist: Primary Research
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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 | |
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 | |
4. | Is the intervention or procedure feasible? (NA for some epidemiological studies) | Yes | |
Validity Questions | |||
1. | Was the research question clearly stated? | Yes | |
1.1. | Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? | Yes | |
1.2. | Was (were) the outcome(s) [dependent variable(s)] clearly indicated? | Yes | |
1.3. | Were the target population and setting specified? | 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 | |
2.2. | Were criteria applied equally to all study groups? | 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 | |
3. | Were study groups comparable? | Yes | |
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 | |
3.3. | Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) | 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? | Yes | |
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 | |
4. | Was method of handling withdrawals described? | 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%.) | Yes | |
4.3. | Were all enrolled subjects/patients (in the original sample) accounted for? | Yes | |
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 | |
5. | Was blinding used to prevent introduction of bias? | Yes | |
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.) | N/A | |
5.3. | In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? | Yes | |
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 | |
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 | |
6.2. | 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 | |
6.4. | 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 | |
6.6. | 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 | |
6.8. | 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 | |
7.1. | 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 | |
7.3. | 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 | |
7.5. | Was the measurement of effect at an appropriate level of precision? | Yes | |
7.6. | Were other factors accounted for (measured) that could affect outcomes? | No | |
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? | No | |
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? | Yes | |
8.3. | Were statistics reported with levels of significance and/or confidence intervals? | Yes | |
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)? | No | |
8.5. | Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? | No | |
8.6. | Was clinical significance as well as statistical significance reported? | Yes | |
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? | Yes | |
9.1. | Is there a discussion of findings? | Yes | |
9.2. | Are biases and study limitations identified and discussed? | No | |
10. | Is bias due to study's funding or sponsorship unlikely? | No | |
10.1. | Were sources of funding and investigators' affiliations described? | Yes | |
10.2. | Was the study free from apparent conflict of interest? | Yes | |