EAL

H/A: Body Composition Measurement (2009)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To determine whether alterations in body composition, resting energy expenditure (REE) and dietary energy intake are associated with growth retardation in HIV-positive children.

Inclusion Criteria:

Children with perinatally acquired HIV infection who were observed in the Intensive Primary Care clinic at the Johns Hopkins Children's Center and their HIV-uninfected siblings
Afebrile
Free from acute infection.

Exclusion Criteria:

Febrile
Presenting with an acute infection.

Description of Study Protocol:

Recruitment

The study population consisted of children with perinatally acquired HIV infection who were observed in the Intensive Primary Care Clinic at the Johns Hopkins Children's Center and their HIV-uninfected siblings, during a two-year period between 1994 and 1996
Children were divided into three groups as follows:
- HIV infected with growth retardation (HIV+Gr)
- HIV infected with normal growth (HIV+)
- HIV uninfected (HIV-).

Design

Cross-sectional study.

Statistical Analysis

One-way analysis of variance was used to determine whether statistically significant differences in REE or body composition existed between groups according to growth parameters and symptomatology
Pearson's R was used to analyze the correlations between CD4 cell number, REE, growth and body composition.

Data Collection Summary:

Timing of Measurements

Children were admitted to the Pediatric Clinical Research Unit of the Johns Hopkins Hospital during a two-year period between 1994 and 1996.

Dependent Variables

Height, weight
Upper arm circumference
Skinfold thicknesses (triceps, subscapular and suprailiac)
REE determined by indirect calorimetry
Body composition determined by deuterium oxide dilution in 34 children
Energy intake determined through 24-hour weighed food intake.

Independent Variables

HIV status
Children were divided into three groups as follows:
- HIV infected with growth retardation (HIV+Gr)
- HIV infected with normal growth (HIV+)
- HIV uninfected (HIV-).

Control Variables

Age
Gender.

Description of Actual Data Sample:

Initial N: 42 children were admitted for study
Attrition (final N): 34 children (insufficient sampling of urine or saliva precluded analysis in seven children)
Age: Between two to 11 years of age
Other relevant demographics: Groups were similar in terms of age and gender.

Anthropometrics

Mean CD4 cell number was significantly lower in the HIV+Gr group
All HIV+ children were receiving antiretroviral therapy.

Location

Baltimore, MD.

Summary of Results:

Findings

All mean anthropometric measurements were lower in HIV-seropositive compared with HIV-seronegative children, reflective of their smaller body size for chronologic age
Lean body mass was significantly reduced in HIV+Gr compared with HIV- (P<0.05) and fat mass was significantly reduced in HIV+Gr and HIV+ compared with HIV- (P<0.05)
Only differences between upper arm circumference and arm muscle area were statistically significant between the groups
Total body water was significantly lower in HIV+Gr compared with HIV- children by both assessment methods
Fat mass estimated from deuterium oxide dilution was significantly reduced in both groups of HIV-seropositive children compared with HIV-seronegative children
Mean fat mass estimated from skinfold thickness measurements was not significantly different between groups
No significant difference was found in the percentage of lean or fat mass among the groups using either method of assessment, suggesting that differences in lean and fat mass were proportional to differences in body size
No significant correlations obtained between growth or body composition measurements and symptomatology according to CD4 cell number
REE was highly correlated with lean body mass in the study subjects (R=0.72; P<0.001)
There was a statistically significant (P<0.05) increase in REE per kg of body weight between HIV+Gr and HIV-
No significant differences were determined in mean energy intake among the groups
The groups were similar in terms of their energy intake as a percentage of REE
No statistically significant correlation was found between energy intake and height or weight-for-age Z-scores.

Author Conclusion:

This study suggests that lean and fat mass are proportionately reduced in HIV-positive children with growth retardation.

Funding Source:

Government:

National Institutes of Health Grants RR-00052 and U01AI2756506

Not-for-profit

Foundation associated with industry:

Reviewer Comments:

Further studies are necessary to delineate the relationship between energy balance and growth in children with HIV infection
This research suggests that lean and fat body mass are proportionally reduced in HIV-positive children with growth retardation
Small sample size and wide variability in age and body size may limit interpretation of the data.

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)	N/A
	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)	N/A

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?	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?	???
3.	Were study groups comparable?		???
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	Yes
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	No
	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?	???
	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.)	???
	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?		Yes
	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.)	Yes
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	Yes
	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?	N/A
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	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?	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)?	Yes
	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