CD: Quality of Life (2006)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To assess aspects of the quality of life of adult celiac patients who had been on a gluten-free diet for 10 years.
Inclusion Criteria:
All patients had diagnosis confirmed by jejunal biopsy showing lesions compatible with celiac disease.  All patients had been started on a gluten-free diet with early clinical response as unequivocal, partial or absent.
Exclusion Criteria:
Excluded if not included above.
Description of Study Protocol:

Recruitment

Diagnosed in routine practice at 6 Swedish hospitals between 1984 and 1988.

Design

Cross-Sectional Survey.

Blinding used (if applicable)

Not applicable.

Intervention (if applicable)

Subjects completed SF-36 and GSRS.

Statistical Analysis

Student's t test for independent samples was used for comparing group means.  The chi-square test was used for comparison of proportions.  The degree of relationship between dependent variables was expressed by means of Pearson's coefficient of correlation.  The frequency distribution was examined with the chi-square goodness of fit test.

Data Collection Summary:

Timing of Measurements

Subjects completed SF-36.  A repeat intestinal biopsy was performed in eligible patients and related the findings to the appearance of the intestinal mucosa.  Subjects in histological remission completed the GSRS.

Dependent Variables

  • Subjective health status measured with SF-36
  • Gastrointestinal symptoms measured with GSRS
  • Repeat intestinal biopsies

Independent Variables

  • Gluten-free diet for 10 years.  Compliance was self-reported as complete, partial or none.

Control Variables

 

Description of Actual Data Sample:

Initial N: 108 adult celiac patients.

Attrition (final N):  89 (82%) completed, 61% women.  60 in histologic remission.  14 refused to participate and 5 had moved away.

Age:  Aged 35 - 74 years 

Ethnicity: Not mentioned

Other relevant demographics:

Anthropometrics

Location:  Sweden 

 

Summary of Results:

 

Female Celiacs Female Controls Male Celiacs Male Controls
Physical Functioning 80.0 +/- 21.3 83.3 +/- 21.2 87.1 +/- 16.1 87.3 +/- 19.9
Role Physical 76.4 +/- 36.5 79.4 +/- 35.0 87.1 +/- 28.7 81.7 +/- 33.1
Bodily Pain 65.1 +/- 24.8 70.3 +/- 27.3 81.9 +/- 20.3, p < 0.05 74.7 +/- 26.6
General Health 62.7 +/- 24.5, p < 0.01 72.9 +/- 23.7 77.1 +/- 22.4 73.9 +/- 22.4
Vitality 55.5 +/- 25.6, p < 0.01 67.2 +/- 24.1 74.0 +/- 22.6 70.7 +/- 23.1
Social Functioning 82.6 +/- 23.8 86.7 +/- 21.9 93.6 +/- 10.7, p < 0.05 89.1 +/- 20.9
Role Emotional 72.8 +/- 38.9, p < 0.05

83.5 +/- 31.4

86.7 +/- 23.2

86.5 +/- 28.0

Mental Health 76.1 +/- 19.3

79.6 +/- 20.1

80.3 +/- 17.7

82.3 +/- 18.6

Other Findings

78% stated they were keeping to a strict GFD, 12% to partial, 10% taking normal diet.

Celiac patients scored significantly lower in the SF-36 than the general population, notably within the General Health and Vitality domains.  There were no differences with regard to age, and patients declaring less compliance showed no lower scores than those keeping with a strict diet.

The low scoring was confined to female patients, particularly in areas of General Health, Vitality and Role Emotional, who also reported significantly more GI symptoms in GSRS than males, in Indigestion and Constipation.

Male celiac patients scored higher than controls in most scales, especially Bodily Pain and Social Functioning.

The functional status and perceived health of celiac patients appeared unrelated to their biopsy findings.

Author Conclusion:
After 10 years on a gluten-free diet, adult celiac patients fail to attain the same degree of subjective health as the general population.  This is particularly true for female patients and suggests that factors beyond normalization of the intestinal mucosa are of importance for the perceived health status of celiacs diagnosed in adult life.
Funding Source:
Government: Medical Research Council of Southeast Sweden
Reviewer Comments:
Compliance was self-reported.  Valid and reliable measures of quality-of life and GI symptoms.  High follow-up rate for 10 years.
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? 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? 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? Yes
  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? 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? Yes
  4.4. Were reasons for withdrawals similar across groups? Yes
  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? Yes
  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? Yes
  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? Yes
  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? 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