ONC: Dietary Supplements and Medical Food Supplements Containing Fish Oil (2013)

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

To examine the effect of dietary compliance post-hoc on intake and body composition in patients with unresectable pancreatic cancer

Inclusion Criteria:

1. Weight loss of greater than 5% in the previous 6 months

2. Life expectancy of greater than 2 months

3. Karnofsky performance score of 60 or more

Exclusion Criteria:

1.  Chemotherapy

2.  Radiotherapy

3.  Surgical treatment in the previous month

4.  Consumption of fish oil capsules

5.  Medications such as steroids that could affect metabolism

Description of Study Protocol:

Recruitment   Post-hoc anaylsis of 200 hundred patients with unresectable adenocarcinomas of the pancreas

Design  Patients were asked to consume 2 cans per day of either a protein and energy dense n-3 fatty acid oral nutritional supplement or an isocaloric, isonitrogenous control supplement without n-3 fatty acids for 8 weeks

Each can contains 1.1g EPA, 310 Kcal, 16g Protein

Statistical Analysis

1. Intent to treat analysis

2. Repeated measures regression models were used to consider the effects of compliance with 1.5 cans of either supplement on a series of nutritional outcomes - energy & protein intake, weight, lean body mass and quality of life

3. Generalized estimating equations were used to permit the inclusion of data from patients with incomplete data records

5. P<0.05 level statistical significance (two tailed)

 

 

 

 

 

 

 

 

 

 

Data Collection Summary:

Timing of Measurements

 Baseline, 4 weeks and 8 weeks

•Dietary intake assessed by food diary completed over 3 consecutive days including 2 weekdays plus one weekend day

•Weight

•Lean Body Mass

•Quality of Life

 

Dependent variables

•Total protein intake (g/day) determined by 3 day food diary plus daily record of number of supplement cans consumed

•Total energy intake (kcal/day) determined by 3 day food diary plus daily record of number of supplement cans consumed

•Weight (kg) measured to the nearest 0.1 kg using a spring balance scale

•Lean body mass measured by an Xitron multifrequency bioelectrical impedance analyzer

•Quality of life measured by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire

Independent variables

•Intake of protein and energy dense oral nutrition supplement +/- n-3 fatty acids

Control variables

•Weekly contact with experienced clinician by either face to face interview or telephone contact for 8 weeks

•Dietary assistance

•Patients encouraged to view supplement as essential component of their treatment

 

 

 

 

 

 

 

 

Description of Actual Data Sample:

 Initial N: 200 patients (n = 95 oral supplement with n-3 fatty acids) (n = 105 oral supplement without n-3 fatty acids)

Attrition (final N):

•Baseline n=185

•4 weeks n=148

•8 weeks n=110

Age:

•Compliant  66.8 +/- 1.0 y.o

•Noncompliant 68.3 +/-1.1 y.o

Ethnicity: None indicated although study was an international multi-centered study

Other relevant demographics:

•The a priori definition of dietary compliance was average consumption over a week period of at least 1.5 cans of either oral nutritional supplement per day

 

Anthropometrics

    Over 8 week period

  Compliant Noncompliant
Body Weight 0.5kg increase 0.7kg decrease
Lean Body Mass no change no change
Plasma EPA Levels 2.7% 1.6%

 

Location: International, multi-centered

 

Summary of Results:

                                                   Averages over 8 weeks

Variables

 Compliant Group

Noncompliant Group Statistical Significance
Total energy intake (kcal/day     1845     1344     <0.001
Total protein intake (g/day)     77.0     51.6     <0.001
Weight (kg)     61.8     60.0     <0.001
Lean body mass     44.1     43.6       0.556
Quality of Life     56.8     52.4       0.075

 

Other Findings

•Supplement intake does not inhibit food intake

•Plasma phospholipid EPA

    • Baseline: p=0.939
    • Week 4: p<0.0001
    • Week 8: p=0.002

 

Author Conclusion:
Compliance with the prescription of 1.5 cans of a protein and energy dense, oral nutrition supplement with or without n-3 fatty acids improved the total dietary intake and body weight in untreated pancreatic cancer patients. However, further research is needed to provide more definitive confirmation of these results.
Funding Source:
University/Hospital: Universität Erlangen-Nürnberg (Germany)
Reviewer Comments:

Limitations:

3 day food diary may not have been an accurate representation of patient's habitual dietary intake

•Clinically important differences in baseline quality of life between the compliant and noncompliant groups

•Large drop out rate - no reasons given

•Posthoc analysis should be viewed with considerable skepticism. 

•Severe pain, nausea and vomiting (all symptoms common in unresectable pancreatic cancer patients),which could affect results not reported

 

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
  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? ???
  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? No
  2.4. Were the subjects/patients a representative sample of the relevant population? ???
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) No
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? ???
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  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
  3.6. 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? No
  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%.) No
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? No
  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? Yes
  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.) ???
  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
  5.5. 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? Yes
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  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? No
  6.6. Were extra or unplanned treatments described? No
  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? 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? 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)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? Yes
  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? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes