CD: Oats and Gluten Intolerance (2005)

Citation:

Srinivasan U, Leonard N, Jones E, Kasarda DD, Weir DG, O'Farrelly C, Feighery C. Absence of oats toxicity in adult celiac disease. BMJ 1996; 313: 1300-1301.

PubMed ID: 8942690
 
Study Design:
Non-Randomized Controlled Trial
Class:
C - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
To examine the clinical, histological, and immunological responses of adult patients with CD to challenge with oats.
Inclusion Criteria:
CD in clinical and histological remission.
Exclusion Criteria:
None defined.
Description of Study Protocol:

Recruitment

  • 10 adult patients recruited from the celiac outpatient clinic in Dublin.

Design

  • Nonrandomized clinical trial.

Blinding used (if applicable)

  • No blinding used.

Intervention (if applicable)

  • Adult subjects consumed 50 g of oats daily for 12 weeks while maintaining a GFD.

Statistical Analysis

  • Results presented as mean (SE).
Data Collection Summary:

Timing of Measurements

Patients assessed clinically at zero, one, four and 12 weeks, with full hematological profiles, biochemical profiles and serological tests for antibodies to gliadin and endomysium. Duodenal biopsies obtained before start of oats challenge and after 12 weeks. Subjects recorded diet compliance daily.

Dependent Variables

  • Duodenal biopsies obtained endoscopically. Specimens underwent standard evaluation for evidence of morphological damage. Two independent observers performed intraepithelial lymphocyte (IEL) counts and enterocyte height measured by computerized image analysis.
  • Hematological and biochemical profiles
  • Serological tests for antibodies to gliadin and endomysium 

Independent Variables

  • Oats cereal included in porridge was tested for evidence of gluten contamination using reverse phase HPLC, ELISA and polymerase chain reaction techniques and was shown to be entirely gluten free. Daily intake targeted at 50 g. Patient compliance was recorded daily using diaries.
Description of Actual Data Sample:

  • Initial N: 10 adults
  • Attrition (final N): 10 adults
  • Age: Not mentioned 
  • Ethnicity: Not mentioned 
  • Other relevant demographics: Not mentioned 
  • Anthropometrics: Not mentioned
  • Location: Dublin, Ireland.
Summary of Results:

AGA Before

AGA After EMA Before EMA After Histology Before Histology After IEL Count Before IEL Count After

Enterocyte Height Before (um)

Enterocyte Height After (um)

1

<1

<1

Neg

Neg

Normal

Normal

16

14

36.3

35.3

2

<1

<1

Neg

Neg

Normal

Normal

26

15

36.0

38.3

3

<1

<1

Neg

Neg

Normal

Normal

19

13

40.8

37.9

4

<1

<1

Neg

Neg

Normal

Normal

6

13

44.9

37.6

5

<1

<1

Neg

Neg

Normal

Normal

22

32

32.8

28.8

6

<1

<1

Neg

Neg

Normal

Normal

17

18

28.8

27.1

7

7

8

Neg

Neg

Normal

Normal

36

20

38.4

42.6

8

<1

<1

Neg

Neg

Normal

Normal

15

13

31.1

34.7

9

<1

<1

Neg

Neg

Normal

Normal

23

13

29.8

30.6

10

<1

<1

Neg

Neg

Normal

Normal

13

13

30.2

36.8

Mean (SE)

 

 

 

 

 

 

19 (2.5)

16 (1.9)

35 (1.7)

35 (1.5)

Other Findings

  • All patients complied fully with the protocol for daily intake of 50 g oats.
  • Throughout the oats challenge, all patients remained asymptomatic with normal hematological and biochemical indices.
  • Two patients were subsequently given a gluten "micro-challenge" of 500 mg gluten daily for six weeks. Both developed histological evidence of relapse and, in one patient, the antibody tests became positive.
Author Conclusion:
This study shows the safety of adding oats to the GFD of 10 patients with CD. Seven of the patients have continued to take the same quantity of oats for more than 12 months without adverse effect. Our results suggest that oats cereal is neither toxic nor immunogenic in CD. This has important implications for the celiac population, since the inclusion of oats would substantially improve the fiber and nutrient content of their GFD. The knowledge that oats are not toxic may help to define the toxic moiety in other cereals.
Funding Source:
Other: reported: NO funding
Reviewer Comments:
Small sample size and trial length of only 12 weeks. Author notes that they chose not to exclude patients with "severe" disease. Two of the patients were subsequently shown to be extremely sensitive when given a gluten micro-challenge.
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? ???
  2.2. Were criteria applied equally to all study groups? N/A
  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) 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? 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? Yes
  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%.) Yes
  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? 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.) 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? 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? N/A
  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? 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? 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? ???
  7.6. Were other factors accounted for (measured) that could affect outcomes? N/A
  7.7. Were the measurements conducted consistently across groups? N/A
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? ???
  8.1. Were statistical analyses adequately described and the results reported appropriately? No
  8.2. Were correct statistical tests used and assumptions of test not violated? ???
  8.3. Were statistics reported with levels of significance and/or confidence intervals? No
  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? No
  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