EAL

H/A: Dietary Intake (2007)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To examine the relationship between depression and changes in dietary macronutrient intake.

Inclusion Criteria:

Patients age 18 years or older at all stages of HIV disease, regardless of their use of antiretrovirals
Special efforts were made to enroll women and minorities.

Exclusion Criteria:

Pregnancy
Severe diarrhea
Thyroid disease
Malignancies other than Kaposi sarcoma
Poor English language fluency at the time of recruitment.

Description of Study Protocol:

Recruitment

Participants in the Nutrition for Healthy Living Study, an observational cohort study of nutritional problems in adults with HIV who were followed up from 1995 to May 2005. Participants were recruited through advertisements in local newspapers, radio, health clinics and physician networks.

Design

Case-control study.

Statistical Analysis

Baseline sociodemographic, clinical and nutritional characteristics were compared between groups using the chi-squared statistic for categorical variables, the T test for normally distributed continuous variables and the Mann-Whitney U test for non-normally distributed continuous variables
Changes in viral load, CD4 count, body mass intake (BMI) and symptom score for depressed and non-depressed participants were compared using the Wilcoxon signed rank test for related samples
The association between depression and change in each macronutrient intake was tested, adjusting for confounding using multiple regression analysis
To determine which variables to include as confounders in each model, the association between each potential confounder with the change in each macronutrient intake was evaluated using Spearman's correlation test for continuous variables, the Mann-Whitney U test for dichotomous variables and the Kruskal-Wallis test for variables with more than two levels.

Data Collection Summary:

Timing of Measurements

Data were collected at baseline and at semi-annual follow-up visits from 1995 to May 2005. Participants who had at least four study visits were considered for this analysis.

Dependent Variables

Changes in macronutrient intake
Dietary intake was assessed by three-day food records or 24-hour recall and calculated.

Independent Variables

People with HIV infection who developed depression vs. those who did not
Depression measured by an interviewer-administered eight-item screening questionnaire developed by Burnam et al.

Control Variables

Age
Sex
Education
Race
Personal income
BMI
Aggregate symptom score
Log₁₀ viral load
CD4 count.

Description of Actual Data Sample:

Initial N

881 participants were enrolled during a 10-year period.

Attrition (final N)

Depression developed in 90 patients (37.9% female), 152 non-depressed control subjects (20.1% female).

Age

Mean age=42 years.

Ethnicity

Developed depression: 31.1% African-American, 7.8% Hispanic/Latino, 57.8% white, 3.3% others
Did not develop depression: 24.3% African-American, 4.6% Hispanic/Latino, 65.1% white, 5.9% others.

Other relevant demographics

The two groups had similar age and BMI at baseline, but those in whom depression developed were more likely to be female, less educated and have lower incomes.

Anthropometrics

Developed depression: median CD4 count=470cells per mm³
Did not develop depression: median CD4 count=340cells per mm³.

Location

United States: Boston, MA, and Providence, RI.

Summary of Results:

Key Findings

At baseline, there were no differences between depressed and non-depressed participants in total daily energy intake or in any component of intake
There was a significant increase in the symptom score (15 vs. 18, P=0.008) among those who became depressed, but no change (nine vs. 10, P=0.1) in non-depressed participants
After adjustment, compared with non-depressed participants, those in whom depression developed had significantly greater decreases in the following daily intakes: total energy (–341kcal, P=0.006), protein (–12.3g, P=0.02), total fat (–18.5g, P=0.008), carbohydrate (–36.8g, P=0.02), total fiber (–4.3g, P=0.001) and saturated fat (–6.7g, P=0.01)
There were no significant differences in the daily intakes of simple sugars and long-chain n-3 fatty acids or BMI.

Author Conclusion:

In conclusion, we found that patients in whom depression developed also reported reduced total energy intake and reductions in intake of six of eight dietary components. To our knowledge, this is the first time that changes in dietary intake have been associated with depression in people with HIV. Depression has been associated with increased mortality in several studies, but the mechanisms that might explain the association are not known. Our findings suggest that poor nutrition should be explored as a potential contributing factor.

Funding Source:

Government:

NIDDK

University/Hospital:

GCRC of Tufts-New England Medical Center

Not-for-profit

Lifespan/Tufts/Brown Center for AIDS Research

Other non-profit:

Reviewer Comments:

Only 242 participants were included out of original 881 in the cohort. Authors note the following limitations:

Determining a clear cause-and-effect relationship between depression and dietary intake for patients with a complex disease such as HIV is difficult
Validity of self-reported dietary data has been controversial
Short screening instrument to detect depression
Findings may not be generalizable to other populations with HIV with different characteristics

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?	???
	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.)	???
	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?		???
	4.1.	Were follow-up methods described and the same for all groups?	???
	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%.)	???
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	???
	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?		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?	Yes
	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?	Yes
	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)?	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