Unintended Weight Loss in Older Adults

Healthy Non-Obese Adults (2010-2012)

Citation:

Nhung BT, Khan NC, Hop LT, Lam NT, Khanh NLB, Lien DTK, Nakamori M, Hien VTT, Kassu A, Yamamoto S.  Resting metabolic rate of elderly Vietnamese.  Ann Nutr Metab 2007; 51:7-13.

PubMed ID: 17356260
 
Study Design:
Cross-Sectional Study
Class:
D - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To evaluate the FAO/WHO/UNU equations for predicting RMR in elderly Vietnamese.

Inclusion Criteria:
  • Healthy elderly subjects aged 60 - 70 years
  • Normal BMI
Exclusion Criteria:
  • No disabilities, hypertension, goiter, or chronic diseases of the heart or lungs
Description of Study Protocol:

Recruitment

120 males and females randomly selected from an urban commune for a screening study.  Listing of people aged 60 - 70 years was constructed and subjects were randomly selected from the list.

Design:  Cross-Sectional Study 

Blinding used (if applicable):  Not applicable

Intervention (if applicable):  Not applicable

Statistical Analysis

Paired t test was used to test differences between measured and predicted values.  Equations derived by linear regression of RMR and body weight were compared to the FAO/WHO/UNU 1985 predictive equations.  Correlation analysis was done to determine relationships between variables. 

Data Collection Summary:

Timing of Measurements

RMR measured and anthropometric indices recorded.

Dependent Variables

  • RMR measured by indirect calorimetry using standard protocol

Independent Variables

  • Height and weight were measured, BMI
  • Body fat percentage measured by bioelectrical impedance
  • Questionnaire about disease history  

Control Variables

 

Description of Actual Data Sample:

Initial N: 120 subjects randomly selected

Attrition (final N):  75 healthy participants, 35 males, 40 females

Age:  mean age males:  65.03 +/- 4.0 years, mean age females:  66.48 +/- 4.61 years

Ethnicity: Vietnamese

Other relevant demographics:

Anthropometrics:

Location:  Hanoi, Vietnam

 

Summary of Results:

 

 

Male > 60 Years

Female > 60 Years
Measured RMR (MJ/day) 5.7836 +/- 0.7203 4.7801 +/- 0.6061

Measured RMR (MJ/kg/day)

0.0963 +/- 0.0121

0.0925 +/- 0.0117

Predicted RMR by WHO (MJ/day)

6.4122 +/- 0.4104

5.3128 +/- 0.1732

Predicted RMR by WHO (MJ/kg/day) 0.1068 +/- 0.0085 0.1028 +/- 0.0065
Difference (%) - overestimation of WHO equations 10.9 (p < 0.05) 11.1 (p < 0.05)

Other Findings

There were significant differences in weight, height, BMI, and body fat percent between male and female subjects (p < 0.05).

Measured RMR was significantly correlated with body weight, BMI and body fat percent in both males and females (p < 0.01).

The correlation between physical activity and RMR was found significant only in males (p < 0.01).

Mean RMRs (MJ/kg/day) were 0.0963 +/- 0.0121 for males and 0.0925 +/- 0.0117 for females, and differences were not statistically significant.

Compared to the FAO/WHO/UNU equations, findings were 10.9% lower in males and 11.1% lower in females (p < 0.05). 

In males, 51.5% had measured RMR within 10% of predicted RMR and in females, 47.5% had measured RMR within 10% of predicted RMR by the FAO/WHO/UNU equations.

Author Conclusion:

In conclusion, our study showed that the FAO/WHO/UNU equations overestimated RMR in elderly Vietnamese by 10.9% in males and 11.1% in females.  The measured values were not significantly different to the estimated values by Japanese and Henry and Rees equations, suggesting that the equations generated for Asians may be more appropriate for Vietnamese.  Further studies on energy metabolism and energy requirements of the elderly are needed. 

Funding Source:
University/Hospital: Ochanomizu
Reviewer Comments:
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? N/A
  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? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  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.) 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? 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? N/A
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