EAL

H/A: Dietary Intake (2007)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To assess the plasma fatty acid status of a group of well-nourished children with the human immunodeficiency virus type 1 and how this relates to the blood total CD4+ lymphocyte count.

Inclusion Criteria:

Weight-for-age and height-for-age values above the third percentile
No decrease in the percentile values of growth parameters during the last 12 months.

Exclusion Criteria:

None specifically mentioned.

Description of Study Protocol:

Recruitment: Recruitment methods not described
Design: Case-control study.

Statistical Analysis

Comparisons between the study population and the control group were analyzed by Student's T-test and fatty acid levels in the HIV-1 seropositive subgroups were compared by the Mann-Whitney U-test.
Correlation tests (Spearman's R) were performed to investigate the relationships between PUFAs, with the product-precursor ratios and total CD4+ count.

Data Collection Summary:

Timing of Measurements

First recall administered the day the blood sample was taken and by home interview on two other days within the next two weeks.

Dependent Variables

Fatty acid composition of plasma total lipids measured by high-resolution capillary gas-chromatography
Blood total CD4+ count in HIV-1 seropositive subjects determined by flow cytometry.

Independent Variables

Dietary habits measured by three 24-hour dietary recalls administered to mothers in consecutive weeks.

Description of Actual Data Sample:

Initial N: 14 HIV-1 seropositive children (seven males, seven females); control group of 30 healthy children
Attrition (final N): 14 cases, 30 controls
Age: One to 13 years
Ethnicity: Not mentioned
Anthropometrics: Controls were in same age bracket as subjects with HIV-1 infection
Location: Italy.

Summary of Results:

	HIV-1 (N=14)	Controls (N=30)	95% CI for Difference	P-Value
Linoleic acid	22.5±3.2	30.0±2.2	-9.17, -5.83	<0.001
Alpha-Linolenic acid	0.22±0.04	0.31±0.11	-0.15, -0.03	0.005
Di-homo-gamma-linolenic acid	2.2±1.6	1.6±0.2	0.01, 1.19	<0.05
Arachidonic acid	8.5±1.8	6.5±0.9	1.18, 2.82	<0.001
Eicosapentaenoic acid	0.42±0.09	0.33±0.11	0.02, 0.16	0.01
Docosahexaenoic acid	1.9±0.7	1.3±0.2	0.32, 0.88	<0.001
Eicosatrienoic acid	0.24±0.19	0.15±0.10	0.00, 0.18	0.05
Saturated fatty acids	36.3±2.6	34.3±1.6	0.72, 3.28	0.003
Monounsaturated fatty acids	26.2±3.1	24.2±2.2	0.36, 3.64	0.01
Polyunsaturated fatty acids	37.3±4.0	42.5±2.5	-7.19, -3.28	<0.001

Other Findings

Concentrations of plasma total fatty acids were not different between the two groups
HIV-1 seropositive children presented lower levels of 18-C essential polyunsaturated fatty acids and higher levels of their 20-C long-chain derivatives and docosahexaenoic acid in their plasma total lipids
The lowest plasma linoleic acid levels were observed in the subgroup of patients with more advanced stages of disease
The plasma linoleic acid levels related positively (Spearman R=0.50, P=0.06), while the linoleic acid-to-arachidonic acid ratio related negatively (Spearman R=-0.51, P=0.06), to the total CD4+ count.

Author Conclusion:

Childhood HIV-1 infection is associated with changes in plasma fatty acid profile suggestive of an increased PUFA turnover. Decreased levels of linoleic acid (together with higher plasma arachidonic acid levels) appear to be associated with more advanced clinical and biochemical stages of disease.

Funding Source:

University/Hospital:

University of Milan Medical School, San Paolo University

Reviewer Comments:

Two control subjects per case
Recruitment methods, inclusion criteria and exclusion criteria not well described
Small number of subjects.

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?	???
	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?	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.)	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?	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?	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?	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?	Yes
	6.6.	Were extra or unplanned treatments described?	Yes
	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?		???
	9.1.	Is there a discussion of findings?	Yes
	9.2.	Are biases and study limitations identified and discussed?	No
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