EAL

CD: Bone Density (2006)

Citation:

Carbone MC, Pitzalis G, Ferri M, Nenna R, Thanasi E, Andreoli A, De Lorenzo A, Bonamico M. Body composition in coeliac disease adolescents on a gluten-free diet: a longitudinal study. Acta Diabetol 2003; 40: S171-173.

PubMed ID: 14618464

Study Design:

Non-Randomized Controlled Trial

Class:

C - Click here for explanation of classification scheme.

Quality Rating:

NEUTRAL: See Quality Criteria Checklist below.

Research Purpose:

To evaluate whether gluten-free dietary treatment during adolescence could prevent permanent modifications in body composition using dual-energy X-ray absorptiometry.

Inclusion Criteria:

Celiac disease adolescents diagnosed according to ESPGHAN Committee on Nutrition criteria on a gluten-free diet from 10 months to 13 years.

Exclusion Criteria:

None specifically mentioned.

Description of Study Protocol:

Recruitment

Not described.

Design

Nonrandomized Clinical Trial, Longitudinal.

Blinding used (if applicable)

No blinding used.

Intervention (if applicable)

Gluten-free diet for 10 months to 13 years. Subjects did not receive vitamin or mineral supplements.

Statistical Analysis

Statistical analysis performed with Student's t test.

Data Collection Summary:

Timing of Measurements

Weight, height, bone mineral content, fat mass, fat-free mass and bone mineral density evaluated at beginning of study and after 4 years. Gluten-free dietary compliance monitored through anti-endomysium antibodies.

Dependent Variables

Fat mass, fat-free mass, bone mineral content and bone mineral density determined through DEXA with a total-body scanner, values obtained using age-specific software

Independent Variables

Gluten-free diet not defined but compliance monitored through anti-endomysium antibodies, which were determined through indirect immunofluorescence

Description of Actual Data Sample:

Initial N: 48 celiac disease adolescents (Group 1A) and 30 healthy children as controls (Group 2A).

Attrition (final N): 11 of 48 celiac disease adolescents recalled 4 years later (Group 1B) and compared with age-and sex-matched healthy controls (Group 2B). 22 of 48 Group 1A and 5 of 11 Group 1B did not comply with the diet completely.

Age: Group 1A: 14.5 +/- 2.8 years; Group 2A: 14.9 +/- 1.9 years, Group 1B: 18.1 +/- 1.6 years, Group 2B: 18.1 +/- 0.9 years

Ethnicity: Not mentioned

Anthropometrics: Groups were not significantly different with respect to age.

Location: Italy

Summary of Results:

	Group 1A	Group 2A	Group 1B	Group 2B
Number (m/f)	48 (15/33)	30 (23/7)	11 (2/9)	11 (2/9)
Age (years)	14.5 +/- 2.8	14.9 +/- 1.9 (NS)	18.1 +/- 1.6	18.1 +/- 0.9 (NS)
Weight (kg)	50.5 +/- 11.8	62.2 +/- 12 (p < 0.001)	55.3 +/- 10.4	69.6 +/- 13.6 (p < 0.005)
Height (cm)	156.4 +/- 10	168.8 +/- 11.3 (p < 0.001)	159.4 +/- 7.5	162.4 +/- 6.5 (NS)
Fat Mass (g)	15643 +/- 6969	12896 +/- 8799 (NS)	17828 +/- 6360	25919 +/- 13229 (NS)
Fat-free Mass (g)	32542 +/- 8461	46250 +/- 12469 (p < 0.001)	34830 +/- 6856	41468 +/- 6931 (p < 0.001)
Bone Mineral Content (g)	2119 +/- 529	2807 +/- 667 (p < 0.001)	2917 +/- 1479	2548 +/- 252 (NS)
Bone Mineral Density (g/cm2)	1.06 +/- 0.106	1.176 +/- 0.125 (p < 0.001)	1.131 +/- 0.087	1.129 +/- 0.08 (NS)

Other Findings

Weight, fat-free mass, bone mineral content and bone mineral density were lower in Group 1A than Group 2A subjects (p < 0.001).

After 4 years, the body compartments of group 1B coeliac disease patients normalized, except for weight and fat-free mass which remained lower than in Group 2B subjects (p < 0.005).

In particular, the 5 patients who did not comply with the diet did not show any significant differences in comparison with the other adolescents who followed a strict gluten-free diet.

Author Conclusion:

Our results agree with other studies performed in pediatric series where a complete restoration of body composition has been reported, whereas in adults some parameters, particularly those of bone, did not normalize after the gluten-free diet. Therefore, adolescence represents a period in which some parameters of body composition can still be recovered after a long-term gluten-free diet as opposed to a short-term gluten-free diet. Occasional alimentary infractions do not seem to be so important for bone compartments, although they have a serious influence on the induction of endocrine auto-antibodies and organ dysfunction.

Funding Source:

Reviewer Comments:

Poor compliance with diet noted. Small number of subjects returning for follow-up after 4 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?		???
	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?	Yes
	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?		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.)	Yes
	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?		No
	4.1.	Were follow-up methods described and the same for all groups?	No
	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?	???
	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?	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