H/A: Caloric Needs (2007)
Citation:
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To determine the relationship between energy metabolism and growth abnormalities in HIV-infected children and to assess clinical or laboratory characteristics that may be contributing factors to their growth impairment.
Inclusion Criteria:
None specifically mentioned.
Exclusion Criteria:
None specifically mentioned.
Description of Study Protocol:
Recruitment
Pre-pubertal children attending the New York Hospital Program for Children with AIDS were recruited.
Design
Cohort study.
Statistical Analysis
- Differences in Z-scores between the group of HIV-infected children with growth impairment and the group with normal growth parameters were assessed by Wilcoxon's rank sum analysis
- Differences between means of continuous data were analyzed by Student's T-test
- Comparison of measured values in HIV-infected subjects to expected age and gender matched normal values utilized the paired Student's T-test
- Distribution of non-continuous data was compared by Fisher's exact test of probability.
Data Collection Summary:
Timing of Measurements
Measurements made at a time point of wellness.
Dependent Variables
- Energy intake measured by inpatient calorie count and outpatient 24-hour food recalls
- Resting energy expenditure measured by indirect calorimetry
- Total energy expenditure measured by doubly-labeled water technique
- Blood samples analyzed for markers of iron, protein and lipid metabolism markers as well as CD4 count, viral load, insulin-like growth factor-1, serum interleukin-6 and whole blood stimulated IL-6 levels.
Independent Variables
Normal or impaired growth pattern.
Description of Actual Data Sample:
- Initial N: 23 HIV-infected children, 15 girls and eight boys
- Attrition (final N): 23
- Age: 1.3 to 13.2 years
- Ethnicity: Not mentioned
- Other relevant demographics: 12 were considered to have normal growth development
- Location: New York.
Summary of Results:
Expected Normal Values for Age and Gender |
All HIV+ Subjects (N=23) |
HIV+ and Normal Growth (N=12) |
HIV+ and Growth-Impaired (N=11) | |
Total EE (kcal/Day) | 1,710.87±70.5 | 1,566.6±119 | 1,521±173 | 1,622±166 |
REE (kcal/Day) |
923.4±53.5 |
937.4±50.4 |
990±59 |
880±83 |
Energy Intake (kcal/kg/Day) |
84.7±3.1 |
75.7±4.7 (P<0.04) |
72±5.8 |
80±7.8 |
Other Findings
- Differences in energy expenditure were not found between normal and growth-impaired HIV-infected children
- Energy intake but not energy expenditure was significantly reduced when HIV-infected children were compared to expected normal values for age and gender (P<0.04)
- Advanced HIV clinical disease, severe immune suppression, increased viral burden, increased IL-6 activity, decreased total serum protein and decreased IGF-1 levels were more likely to be found in HIV-infected children with growth impairment compared to HIV-infected children with normal growth.
Author Conclusion:
- In summary, we have identified several clinical and laboratory determinants which were associated with growth impairment in HIV-infected children
- Advanced HIV clinical disease, severe immune suppression, increased viral burden, increased IL-6 activity, decreased total serum protein and decreased IGF-1 levels were more likely to be found in HIV-infected children with growth impairment than in HIV-infected children with normal growth
- Energy consumed by our cohort of HIV-infected children was found to be substandard when compared to expected normal energy intake.
Funding Source:
Reviewer Comments:
- Inclusion and exclusion criteria were not described
- Authors note that the study is limited by the size of the cohort and the fact that the children were studied at one time-point of wellness.
Quality Criteria Checklist: Primary Research
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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? | No | |
2.2. | Were criteria applied equally to all study groups? | ??? | |
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? | Yes | |
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? | Yes | |
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? | 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.) | 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? | Yes | |
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? | 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? | 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? | 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? | No | |
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 | |