CD: Oats and Gluten Intolerance (2005)

Citation:

Peraaho M, Collin P, Kaukinen L, Miettinen S, Maki M.  Oats can diversify a gluten-free diet in celiac disease and dermatitis herpetiformis. J Am Diet Assoc 2004; 104: 1148-1150.

 
Study Design:
Cross-sectional study
Class:
D - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
To evaluate the adoption of oats and the effect of oats on symptoms and quality of life.
Inclusion Criteria:
Members of the Finnish Celiac Society.
Exclusion Criteria:
None defined.
Description of Study Protocol:

Recruitment

  • Questionnaire mailed to 1,000 randomly selected members of the 14,000 members of the Finnish Celiac Society.

Design

  • Cross-sectional study, survey.

Intervention (if applicable)

Questionnaire comprised seven items asking:

  • Whether patients had tried oats
  • Are currently using oats
  • Whether those with newly diagnosed CD are more willing to eat oats than those who had adhered to the diet for a long time
  • How long and how regularly patients had consumed oats
  • Whether they had developed any symptoms
  • Whether they feel that oats diversify the diet
  • If not using oats, the reasons.

Statistical Analysis

  • Cross-tabulations were carried out using chi-square test.
Data Collection Summary:

 

Description of Actual Data Sample:

  • Initial N: 1,000 mailed questionnaires 
  • Attrition (Final N): 710 respondents (71%), 521 female, 189 male 
  • Age: Median age 52 years; range 5-84 years
  • Ethnicity: Finnish
  • Location: Finland.

 

Summary of Results:

 

Number of Patients

Number Eating Oats

Percent Eating Oats

P-value, Chi-Square Test

Female

521

365

70%

0.71

Male

189

129

69%

 

Celiac Disease

581

423

73%

<0.001

Dermatitis Herpetiformis

127

70

55%

 

Adults >18 years

647

449

69%

0.45

Children < 18 years

56

45

80%

 

Diagnosed before 1997

397

246

62%

0.001

Diagnosed in 1997 or later

295

236

80%

 

Other Findings

  • Altogether, 70% were currently consuming oats: 423 (73%) with CD and 70 (55%) with dermatitis herpetiformis. 15% had never tried to eat oats.
  • Patients with CD consumed oats more often than those with dermatitis herpetiformis. The use of oats was also more frequent in children than adults and in those whose diagnosis was made after the nationwide recommendation.
  • Of all patients, 71 (10.1%) with CD and 27 (18.9%) with dermatitis herpetiformis had stopped using oats due to bloating and diarrhea.
  • The majority (94%) of the 494 patients consuming oats felt that oats diversified the GFD and considered oats to constitute an important part of the diet, 80% appreciated the taste, 91% the ease of using the oat products and 82% the low costs. 
Author Conclusion:
We conclude that, provided safe oat products are available, the majority of CD and dermatitis herpetiformis patients prefer to consume oats. It is well tolerated and patients believe that this increment diversifies the diet. There would appear to be a market demand for uncontaminated oat products and celiac societies and dietitians should make efforts to promote the development of oat products free of wheat contamination.
Funding Source:
University/Hospital: Tampere University Hospital (Finland), Central Hospital of Jyvaskyla (Finland)
Not-for-profit
0
Foundation associated with industry:
Reviewer Comments:
Very high response rate. Not much information provided regarding demographics of the respondents.
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? 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? 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? Yes
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? 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%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? N/A
  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? N/A
  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? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? N/A
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? N/A
  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? N/A
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? 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