Unintended Weight Loss in Older Adults

UWL: Activity Level Factors (2007)


Rothenberg EM, Bosaeus IG, Westerterp KR, Steen BC.  Resting energy expenditure, activity energy expenditure and total energy expenditure at age 91 - 96 years.  Br J Nutr 2000;84:319-324.

PubMed ID: 10967610
Study Design:
Cross-Sectional Study
D - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To measure RMR and TEE in 91 - 96 year old subjects and define activity EE and PAL.

Inclusion Criteria:
  • Mentally healthy
  • >90 years
  • Free- and independently-living, termed healthy
Exclusion Criteria:

Excluded if not included above.

Description of Study Protocol:


Subjects were recruited from survivors in a systematic sample of 1148 70-year olds in Gothenburg who had been followed longitudinally since 1971.  4 individuals were recruited from another population study, the Johannesburg study, which comprised all individuals 70 years of age and over living in a Goteborg, Sweden.

Design:  Cross-Sectional Study 

Blinding used (if applicable):  Not applicable 

Intervention (if applicable):  Not applicable

Statistical Analysis

The components of energy expenditure were standardized for FFM using linear regression analysis.  Means were compared using Student's t test for paired or unpaired samples where appropriate.

Data Collection Summary:

Timing of Measurements

TEE measured over 15 days.

Dependent Variables

  • Total body water measured using doubly labelled water and bioelectrical impedance
  • RMR measured using indirect calorimetry with a ventilated hood system, measured at the laboratory or at home, under standard protocol 
  • Total energy expenditure measured using doubly labelled water
  • Body weight, height, BMI

Independent Variables

  • Aged 91 - 96 years

Control Variables


Description of Actual Data Sample:

Initial N: 21 free-living elderly individuals, 8 males, 13 females

Attrition (final N):  21

Age:  aged 91 - 96 years

Ethnicity: not mentioned

Other relevant demographics:

Anthropometrics:  see Results

Location:  Goteborg, Sweden


Summary of Results:





Height (m)

1.59 +/- 0.08 1.70 +/- 0.04

Body weight (kg)

61.3 +/- 12.5

67.2 +/- 7.3


24.2 +/- 4.4

23.2 +/- 2.4

TBW by DLW (kg) 29.5 +/- 5.4 35.6 +/- 4.3
TBW by BIA (kg) 31.6 +/- 6.4 42.0 +/- 7.4
FFM by DLW (kg) 40.4 +/- 7.3 48.8 +/- 5.9
FFM by BIA (kg) 43.3 +/- 8.8 57.6 +/- 10.2
FM by DLW (kg) 20.8 +/- 8.0 18.3 +/- 4.7
FM by BIA (kg) 17.9 +/- 8.8 9.6 +/- 7.6
TEE (MJ/day) 6.30 +/- 0.81 8.10 +/- 0.73
AEE (MJ/day) 0.95 +/- 0.95 2.02 +/- 1.13
RMR (MJ/day) 5.36 +/- 0.71 6.09 +/- 0.91
PAL (TEE/RMR) 1.19 +/- 0.19 1.36 +/- 0.21

Other Findings

Total body water measured using doubly labelled water was 29.5 +/- 5.4 kg in females and 35.6 +/- 4.3 kg in males.

Total body water measured using bioelectrical impedance was 31.6 +/- 6.4 kg in females and 42.0 +/- 7.4 kg in males.

The mean difference between total body water measured by bioelectrical impedance and that by doubly labelled water was 3.54 +/- 3.6 kg (P = 0.0002).

RMR averaged 5.36 +/- 0.71 MJ/day in females and 6.09 +/- 0.91 MJ/day in males.

The difference between measured RMR and predicted RMR was 0.015 +/- 0.86 MJ/day (P = NS).

Total energy expenditure averaged 6.3 +/- 0.81 MJ/day in females and 8.1 +/- 0.73 MJ/day in males.

Activity energy expenditure (TEE - RMR, including diet-induced thermogenesis) averaged 0.95 +/- 0.95 MJ/day in females and 2.02 +/- 1.13 MJ/day in males.

Physical activity level (TEE/BMR) averaged 1.19 +/- 0.19 in females and 1.36 +/- 0.21 in males (P = 0.08).


Author Conclusion:

In this sample of very old individuals, TEE, AEE and PAL were lower, while RMR was not substantially different from that of another group of younger elderly.  Values for TEE, AEE and PAL indicate that these individuals have very limited physical activity.

Funding Source:
Foundation associated with industry:
Reviewer Comments:

Small sample sizes.  Not all measurements made in the lab, and authors note that a difference was found according to whether the individuals were measured at home or in the laboratory, thus the RMR data obtained at the laboratory may overestimate true values and underestimate AEE and PAL values.

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? 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? ???
  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? ???
  7.7. Were the measurements conducted consistently across groups? No
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