EAL

ONC: Low Residue (2005)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

The purpose of the study was to identify foods that commonly affect gastrointestinal symptoms after radiation treatments for gynecologic cancers and to provide nutrition management guidelines.

Inclusion Criteria:

The study was limited to patients who met 3 criteria:

Had received external beam radiation therapy ranging from 4,500 to 5,500 cGy for gynecological malignancies
Had concluded treatment at least 6 months prior to the study
Were clinically free of disease at the time the study questionnaire was administered

Exclusion Criteria:

Patients were excluded from the study if they had undergone GI surgery or had a history of GI disease.

Description of Study Protocol:

Recruitment:

Patients were identified through outpatient clinics
Recruiting method is not described

Design:

Patients were divided into 2 groups:
- Those with documented symptoms of chronic radiation enteritis as identified by physician's notes
- Those with no documented symptoms of chronic radiation enteritis

Blinding used (if applicable)

Intervention (if applicable):

A self-assessment questionnaire was administered. The questionnaire was divided into three main parts:
- Part one: General section which was verified and completed, if necessary, using information from the patient's clinic record
- Part two: Asked if particular foods made the patient's symptoms:
  - Worse, and, if so, the quantity of food involved
    - Quantity was categorized as either small (< 1/2 cup) or normal (> 1/2 cup) portions
  - Better
  - No change
  - Item not consumed
- Part three: Provided open-ended questions to allow inclusion of other foods and/or situations relevant to GI symptoms
The questionnaire was administered during clinic visits in the presence of a registered dietitian

Statistical Analysis:

Contingency tables were used to determine frequencies of foods that affect GI symptoms
X² test was applied to determine differences between the group with documented chronic radiation enteritis and the control group without chronic radiation enteritis
If responses were fewer than 5 in any group, the Fisher exact test was applied
NCSS statistical program was used

Data Collection Summary:

Timing of Measurements:

Questionnaires were completed by patients during clinic visits.
One-time gathering of data (one questionnaire per patient)

Data provided by questionnaire:

Difference in GI symptom exacerbation reported by documented chronic radiation enteritis group and control group without documented chronic radiation enteritis
Foods causing the highest percentage of GI symptoms
Portion sizes tolerated
Tolerance of high-fat foods
Tolerance of lactose-containing dairy products
How tolerated foods were identified by patients
Dietary habits of patients

Foods listed on questionnaire:

Breads and cereals: Bran cereal, bran muffin, brown rice, rye bread, whole-wheat bread
Fruits and vegetables: Berries, brocolli, brussels sprouts, cabbage, caesar salad, corn, dried fruit, eggplant, kiwi, parsnips, peas, rhubarb, spinach, tossed salad
Dairy products: Cream soup, ice cream, milk (partly skim), milk pudding, yogurt
Meats and fats: Fried chicken, fried fish, gravy, sausage (2 links), salad dressing (1 Tbsp)
Other foods: Baked beans, dried beans and lentils, lima beans, nuts, popcorn

Dependent Variables: NA

Independent Variables: NA

Control Variables: NA

Description of Actual Data Sample:

Initial N: 48 patients, divided into 2 groups

Group with documented chronic radiation enteritis: n = 26
- Mean age: 60.1 years; SD =14.2
- Mean height: 159.6 cm; SD = 6.1
- Mean weight: 66.0 kg; SD = 14.7
- Median time since radiation treatment: 25 months (range: 9-176 months)
Group without documented chronic radiation enteritis (control group): n = 22
- Mean age: 63.1 years; SD = 12.3
- Mean height: 160.7; SD = 7.1
- Mean weight: 66.6 kg; SD = 9.4
- Median time since radiation treatment: 35 months (range: 16-344 months)

Attrition (final N): 48 patients

Ethnicity: Not mentioned

Other relevant demographics:

All GI symptoms, with the exception of urgency with defecation, were significantly higher in the documented chronic radiation enteritis group
- Symptoms included bloating, gas, abdominal cramps, diarrhea, and urgency with defecation
Location of cancers:
- Cervical: 46% group with documented chronic radiation enteritis; 36% group without radiation enteritis
- Endometrium: 39% group with documented chronic radiation enteritis; 55% group without radiation enteritis
- Ovary, uterus: 15% group with documented chronic radiation enteritis; 9% group without radiation enteritis

Anthropometrics: Groups were similar in age, height, weight, and distribution of cancer site

Location: Outpatient clinics; study author is a consultant for the British Columbia Cancer Agency, Vancouver, British Columbia

Summary of Results:

Data	Treatment Group	Control group	Statistical Significance of Group Difference
GI symptom exacerbation associated with listed foods	Reported to varying degrees for all 34 foods listed on the questionnaire	Reported for 12/34 listed foods	NA
GI symptom exacerbation associated with small portions (< 1/4 cup) of listed foods	% reporting symptoms for small portions ranged from 4-65% for various listed foods	% reporting symptoms for small portions was no greater than 5% for any listed food	P<.05
GI symptom exacerbation associated with normal portions (> 1/2 cup) of listed foods	% reporting symptoms for normal portions ranged from 8-69% for various listed foods	% reporting symptoms for normal portions ranged from 5-18% for various listed foods	P<.05

Other Findings

The difference between the two groups was highly significant (P<.0005) for brocolli, Brussels sprouts, cabbage, spinach, tossed salad, baked beans, dried beans and lentils, nuts.
35% of patients with documented chronic radiation enteritis made the comment that raw fruits and vegetables exacerbated their symptoms. No member of the control group made this comment
A significant difference (P<.05) was observed in the portion sizes tolerated by the two groups.
Less than 20% of the group with documented chronic radiation enteritis had difficulty tolerating high-fat foods, possibly because 1/3 of the group was deliberately trying to reduce fat intake.
<15% of the group with documented chronic radiation enteritis had difficulty tolerating lactose-containing foods, with the exception of milk (23%) and ice cream (27%), suggesting that dietitians can encourage patients to include these foods in small portions or with other foods to minimize discomfort.

Author Conclusion:

Normal portions of all foods with moderate/high fiber content appear to exacerbate GI symptoms in patients with chronic radiation enteritis.
For some patients, even small portions of moderate/high fiber foods aggravate symptoms.
Eating small portions (<1/4 cup) more often may help to alleviate symptoms.
In the comments section, 27% of patients with documented chronic radiation enteritis said that they identified tolerated foods through trial and error, and that fear of exacerbating symptoms prevented them from retrying foods.
- 23% of patients with documented chronic radiation enteritis resorted to a basic diet with decreased variety
- 38% of patients with documented chronic radiation enteritis were trying to follow healthy eating guidelines and mentioned that they were frustrated with their lack of ability to tolerate foods promoted for cancer prevention.
Further research should explore:
- Quality of life issues for patients with chronic radiation enteritis
- Coping with chronic illness
- Anxiety surrounding meals

Funding Source:

Government:

British Columbia Cancer Agency

Reviewer Comments:

The author mentions that the actual content of a low-residue diet is not defined, and that confusion exists among dietitians as to the exact composition of a low-residue diet.

This study was well-designed to achieve its purpose of identifying foods that commonly exacerbate GI symptoms following radiation treatment for gynecological cancer, and to provide nutrition management guidelines for radiation enteritis.

The long periods of time between radiation treatment and administration of the questionnaire may decrease the reliability of subjects' recalled information.

The study was not well-designed to define the low-residue diet, or to assess its effects. A better approach to this problem would have been a before-and-after study, or a food diary used in conjunction with a standardized GI toxicity scale.

The study did not exclude subjects for lactose intolerance.

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?	N/A
	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?	Yes
	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?	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.)	Yes
	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?		N/A
	4.1.	Were follow-up methods described and the same for all groups?	N/A
	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%.)	N/A
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	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?		???
	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?	Yes
	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?	N/A
	6.6.	Were extra or unplanned treatments described?	N/A
	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?		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?	N/A
	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?	N/A
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	N/A
	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)?	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
9.	Are conclusions supported by results with biases and limitations taken into consideration?		???
	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?		???
	10.1.	Were sources of funding and investigators' affiliations described?	???
	10.2.	Was the study free from apparent conflict of interest?	???