ONC: Dietary Supplements and Medical Food Supplements Containing Fish Oil (2013)
Does dietary polyunsaturated fatty acids have an effect on T-lymphocyte subpopulations and natural killer cells of patients with solid tumors?
- Solid tumors
- Malnourished, though no specifics
- Not currently receiving treatment with chemotherapy or immunomodulating agents
Not indicated
Recruitment
Recruitment procedures not indicated.
Design
- Approved by Hospital Ethics Committee
- Both malnourished and controls received 18 grams of Fish oil per day for 40 days
- Peripheral blood leukocytes and lymphocytes, Tcells, T-helper cells, T-suppressor cells, helper:suppressor cell ratio(H/S) and NK cells were measured before fish oil supplementation and for 40 days during fish oil supplementation.
- Monoclonal antibodies and immunofluorescence microscopy was used to study the lymphocyte subsets.
Intervention
- 18 grams of Fish oil per day for 40 days.
Statistical Analysis
- Mean value +/- standard deviation
- Student's t test for statistical analysis
Timing of Measurements
- Measurements were provided before and after 40 consecutive days of supplementation of 18 grams of fish oil
Dependent Variables
- Peripheral blood leukocytes and lymphocytes
- T-cells (total)
- T-Helper (CD-4) cells
- T-Suppressor (CD-8) cells
- Helper:suppressor cell ratio (H/S)
- NK cells
Other dependent variables include: Karnofski value, total or partial response, survival, body weight, serum albumin or serum transferrin (although details of testing and actual values not provided in the study).
Independent Variables
- 18 grams of fish oil
Control Variables
Initial N: 20 malnourished patients, 12 males and 8 females
10 controls (sex not indicated)
Attrition (final N): N=20
Age: mean age of 58.5 years (42-65)
Controls: 61.5 years (range 44-76 years)
Ethnicity: Not indicated
Other relevant demographics: N=12 metastatic gastrointestinal cancer patients, N=6 lung cancer patients, N=2 breast cancer patients
Anthropometrics Not indicated
Location: Does not indicate where patients received treatment other than fish oil came from Athens Greece and researchers are from Patras University, Patras, Greece
Table 1
Percentage Numbers (% of Blood Lymphocytes) of T-Lymphocytes Subpopulations including Total T Cells, Helper(CD4) and Suppressor (CD8) T Cells, Helper: Suppressor(H/S) Cell Ratio, and NK Cells of Controls and Cancer Patients, Before and 40 Days into Dietary Supplementation with Omega-3 Fatty Acids
T-Cell Subsets |
Controls (%) |
Cancer Patients (%) Before |
Cancer Patients(%) After |
Total
|
65.3 +/-14.6
|
58.7 +/-13.3 | 52.0 +/-13.8 |
CD4
|
44.7 +/-10.8 | 36.5 +/-11.2 | 35.4 +/-12.7 |
CD8 |
20.1 +/-8.7
|
29.7 +/-9.4
|
18.9 +/-7.5a |
H/S
|
2.17 +/-0.51 |
1.20 +/-0.26 |
1.74 +/-0.4 a |
NK
|
13.2 +/-3.9 |
11.4 +/-3.3 |
13.3 +/-4.5 |
a denotes p<0.05
Values are expressed as mean +/- SD.
Table 2
Absolute Numbers (per mm3) of Blood Leukocytes, Lymphocytes Total T Cells, Helper (CD4) and Suppressor (CD8) T Cells, and NK Cells of Controls and Cancer Patients, Before and 40 Days into Dietary Supplementation with Omega-3 Fatty Acids
Cell Numbers |
Controls |
Cancer Patients Before |
Cancer Patients After |
Leukocytes
|
6890 +/-1340 | 7190 +/-1645 | 5690 +/-1352 |
Lymphocytes
|
2411 +/-592 | 2158 +-543 | 1991 +/-388 |
Total T cells |
1575 +/-352
|
1267 +/-287 | 1037 +/-275 |
CD4 |
1078 +/-260
|
787 +/-241
|
705 +/-253 |
CD8 |
484 +/-209
|
641 +/-202 |
376 +/-149a |
NK |
318 +/-94
|
246 +/-71 |
265 +/-90 |
a denotes p < 0.01
Values are expressed as mean +/- SD.
Other Findings
- Absolute and percentage numbers of total T cells, helper T cells and NK cells before and after omega-3 supplementation were not significantly different
- No differences found in Karnofski value, total or partial response, and survival in patients receiving supplementation vs those were who not receiving supplementation
- Body weight, serum albumin, and serum transferrin were similar in all patients before and 40 days after dietary supplementation with Omega-3 fatty acids.
- Omega-3 Fatty Acid supplementation may provide some beneficial effects on the immune system of malnourished cancer patients.
- Most significant effects were noted as an increase in helper:suppressor T-cell ratio in patients with gastrointestinal and lung cancer as a result of a significant decrease in suppressor T-cells.
- Omega-3 fatty acids may have an inhibitory effect on on immunosuppressive substances such as PGE2 which may indirectly have an impact on suppressor T cells.
- Small sample size
- Short term study
- Mixed cancer sites
- No mention of dietary intake prior to and during study
- No mention of how patients were characterized as malnourished
- Compliance to intervention was not measured
- No mention of drop out rate
- Clinical data representing nutritional status was not presented
- No mention of timing of fish oil provided on daily basis
- No blinding
- No control product
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? | No | |
2. | Was the selection of study subjects/patients free from bias? | No | |
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? | No | |
2.2. | Were criteria applied equally to all study groups? | No | |
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? | No | |
3. | Were study groups comparable? | No | |
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? | No | |
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? | No | |
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? | ??? | |
4.4. | Were reasons for withdrawals similar across groups? | 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 | |
5.1. | 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? | 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? | No | |
6.1. | In RCT or other intervention trial, were protocols described for all regimens studied? | ??? | |
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? | No | |
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? | 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? | ??? | |
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? | ??? | |
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? | No | |
7.6. | Were other factors accounted for (measured) that could affect outcomes? | No | |
7.7. | Were the measurements conducted consistently across groups? | No | |
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)? | ??? | |
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? | No | |
8.7. | If negative findings, was a power calculation reported to address type 2 error? | ??? | |
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? | ??? | |
10.1. | Were sources of funding and investigators' affiliations described? | ??? | |
10.2. | Was the study free from apparent conflict of interest? | ??? | |