CD: Oats and Gluten Intolerance (2005)


Reunala T, Collin P, Holm K, Pikkarainen P, Miettinen A, Vuolteenaho N, Maki M. Tolerance to oats in dermatitis herpetiformis. Gut 1998; 43: 490-493.

PubMed ID: 9824575
Study Design:
Non-Randomized Controlled Trial
C - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
To use rash development as an indicator for oat intolerance in patients with dermatitis herpetiformis in remission.
Inclusion Criteria:

None specifically mentioned.

Exclusion Criteria:
None specifically mentioned.
Description of Study Protocol:


  • 12 patients with dermatitis herpetiformis on a conventional GFD recruited. 11 patients with dermatitis herpetiformis volunteered to act as controls.


  • Nonrandomized clinical trial.

Blinding used (if applicable)

  • No blinding used.

Intervention (if applicable)

  • Patients with dermatitis herpetiformis in remission were challenged with 50 g oats/day for six months.

Statistical Analysis

  • Paired t-test was used to compare villous heigh:crypt depth ratios and IEL densities. Two-tailed t-test was used to compare the lymphocyte densities between the patients with dermatitis herpetiformis and controls.
Data Collection Summary:

Timing of Measurements

Clinical symptoms were recorded, serum samples taken, and skin and small bowel biopsies performed before and after oat challenge. Patients were assessed clinically and dietetically 1-2 months before, at beginning, and 1, 3 and 6 months after oat challenge.

Dependent Variables

  • Presence or absence of rash recorded from diaries, checked on visits
  • Skin biopsies taken from forearm and checked for IgA fluorescence
  • Serum samples screened for IgA class endomysial antibodies and IgA class gliadin antibodies
  • Small bowel biopsies taken from distal part of duodenum through upper GI endoscopy and processed for measurement of villous height:crypt depth ratio and immunohistochemical examination.

Independent Variables

  • Patients asked to consume 50 g oats daily as porridge or bread. Oat cereal was given to patients and was determined to be free of gluten contamination by ELISA and polymerase chain reaction methods.
Description of Actual Data Sample:

  • Initial N: 12 patients, 11 controls
  • Attrition (final N): 11 patients (five men, six women), 11 controls (five men, six women). One patient developed scalp rash after six weeks and withdrew.
  • Age: Controls mean age 51 (30-67 years)
  • Ethnicity: Not mentioned.

Anthropometrics (e.g., were groups same or different on important measures)

  • Oat Group: Upon inclusion, patients had been on GFD for a mean of 5.5 years (0.5-19 years), free of rash for mean 14 months (2-48 months) and none of them used dapsone.
  • Controls: Upon inclusion, controls had been on GFD for a mean of 2.5 years (one to four years), rash free for 12 months (four to 24 months) and none had used dapsone.
  • Location: Helsinki University Hospital, Finland.
Summary of Results:

On Oats: Before

On Oats: After


Villous Height:Crypt Depth Ratio

3.0 (1.0)

2.8 (0.8)

3.8 (1.3)


37.6 (16.4)

34.8 (17.5)

25.6 (16.5)

alpha/beta TCR +

14.8 (5.0)

15.1 (7.7)

15.7 (11.8)

gamma/delta TCR +

9.1 (4.8)

6.0 (5.1)

1.5 (1.6)

DR expression in crypts




Other Findings

  • During the oat challenge, patients consumed a mean of 53.2 g oats/day (30-66 g). Mean gluten intake from wheat-starch flours was 40 mg/day (0-150 mg).
  • Eight patients challenged with oats remained asymptomatic, two developed a transient rash lasting three or four weeks. A patient who withdrew at the three-month visit showed a slight decrease in the villous height:crypt depth ratio. Three of the 11 controls also developed a transient rash and had IgA deposits in the skin, but no IgA endomysial or gliadin antibodies. IgA endomysial antibodies remained negative in all patients. The small bowel villous architecture, the densities of intraepithelial CD3 and alpha/beta and gamma/delta T cell receptor positive lymphocytes and crypt epithelial cell DR expression remained unaltered during the oat challenge.
Author Conclusion:
The present six-month challenge study with moderate amounts of oats in patients with dermatitis herpetiformis did not disclose any tendency for reappearance of the rash or signs of immune activation known to occur in the skin, serum or gut mucosa after exposure to wheat gluten. We conclude, therefore, that oats are a new cereal alternative for patients with dermatitis herpetiformis on a strict GFD and whose rash is in remission. The inclusion of oats in a GFD increases the variety of cereals that can be consumed, which may improve compliance and also reduce the otherwise high cost of such treatment.
Funding Source:
University/Hospital: Tampere University (Finland), Medical Academy of Finland
Foundation associated with industry:
Reviewer Comments:
  • Small sample size.
  • None of the subjects had used dapsone.
  • Subjects also consumed gluten from wheat-starch flours.
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? No
  2.2. Were criteria applied equally to all study groups? N/A
  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? ???
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? ???
  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%.) No
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? No
  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? 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? 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? 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? 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? 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