H/A: Body Composition Measurement (2009)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
  • To examine the association of nutritional status with active opportunistic infections among HIV-infected adults in Khon Kaen, Thailand
  • To determine if there was an association between bioelectrical impedance analysis and anthropometric assessment of body composition among HIV-infected adults in this region.
Inclusion Criteria:
  • Participants were more than 18 years of age with a life expectancy greater than 14 days
  • HIV status was determined using available laboratory methods.
Exclusion Criteria:

None specifically mentioned.

Description of Study Protocol:

Recruitment

Convenience sample of HIV-infected adult patients was recruited from Srinagarind Hospital, Khon Kaen University Medical Center during the period March 1999 to May 1999. Subjects were recruited from subsequent patients coming to the outpatient general medicine clinic, the outpatient infection clinic and the inpatient infectious disease service.

Design

Cross-sectional study. 

Statistical Analysis

  • Data were analyzed separately for patients with and without active opportunistic infections
  • Males and females were stratified because of variations in demographics, health status and body composition standards
  • Means, proportions and their standard deviations, as well as associations and unconditional odds ratios were generated by SPSS
  • P-values for differences between active opportunistic infections and no active opportunistic infections were calculated using the non-parametric Mann-Whitney test because the data were not normally distributed
  • Associations and P-values for differences between body fat assessment techniques were calculated using Pearson's chi-square test.
Data Collection Summary:

Timing of Measurements

Measurements made during clinic visit.

Dependent Variables

  • Height, weight, BMI
  • Mid-arm circumference
  • Mid-arm muscle circumference
  • Skinfold measurements of triceps and subscapular taken in triplicate and averaged
  • Bioelectrical impedance analysis conducted using quantum hand-held analyzers.

Independent Variables

HIV infection.

Control Variables

  • Pertinent HIV history
  • Medications
  • Laboratory data.
Description of Actual Data Sample:
  • Initial N: 77 patients
  • Attrition (final N): 77 patients; 50 men, 27 women
  • Age: Mean age, 33.5±7.9 years
  • Other relevant demographics: Mean HIV duration, 39.0±37.0 months
  • Anthropometrics: 19.5% were receiving anti-retroviral therapy, including zidovudine (N=11), didanosine (N=6), lamivudine (N=4), stavudine (N=4), zalcitabine (N=4) and indinavir (N=3). Duration ranged from two weeks to two years.
  • Location: Khon Kaen, Thailand. 
Summary of Results:

Associations Comparing Anthropometric Measurements, Bioelectrical Impedance Analysis (BIA) and Body Mass Index (BMI) to Assess Body Fat Composition

 

R P

BIA fat % and subscapular fat %

0.86 <0.001

BIA fat % and sum of triceps and subscapular fat %

0.79

<0.001

Subscapular fat % and triceps fat % 0.72 <0.001
BIA and sum of triceps and subscapular fat % 0.66 <0.001
BIA fat % and BMI 0.66 <0.001
BMI and triceps fat % 0.61 <0.001
BMI and subscapular fat % 0.60 <0.001
BIA fat % and triceps fat % 0.54 <0.001

Other Findings

Many patients (41.3%) were malnourished using World Health Organization criteria for underweight, and malnutrition was associated with active opportunistic infection status.

Unconditional odds ratios (P<0.05) for active opportunistic infections as opposed to no active opportunistic infections were 4.57 for underweight, 9.87 for severe underweight, 2.55 for triceps less than 10th percentile and 5.22 for mid-arm circumference less than 10th percentile.

Body fat composition from bioelectrical impedance analysis, anthropometry and body mass index were moderate to highly correlated (P<0.001), with the highest correlation between bioelectrical impedance analysis and subscapular skinfold (R=0.86) and the lowest between bioelectrical impedance analysis and triceps skinfold (R=0.54). 

Author Conclusion:

In conclusion, the nutritional compromise in HIV has long been known to be associated with morbidity and mortality. Nearly half (41.3%) of the HIV-infected adults in this study were malnourished using the WHO BMI cut-off for underweight. Such malnutrition was seen in individuals with and without active opportunistic infections, and those who were and were not treated with anti-retroviral therapy. Further study is needed to more fully evaluate the nutritional status of this population, including investigating causes of malnutrition, and exploring the longitudinal relationship between nutrition and HIV disease progression. Ultimately, whether cost-effective nutritional intervention can improve the nutritional status and impact the course of HIV disease in similar settings with limited resources should be assessed. 

Funding Source:
Not-for-profit
0
Foundation associated with industry:
Reviewer Comments:

Authors note the following limitations:

  • There was no HIV-negative control group
  • Cross-sectional study and thus no information was generated about the temporal relationship between nutritional status and development of active opportunistic infections
  • BIA measurements can be affected by disease status.
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? Yes
  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? Yes
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? 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.) 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? 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)? 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