COPD: Determination of Energy Needs (2007)


Slinde F, Ellegard L, Gronberg AM, Larsson S, Rossander-Hulthen L.  Total energy expenditure in underweight patients with severe chronic obstructive pulmonary disease living at home.  Clin Nutr 2003;22(2):159-65.

PubMed ID: 12706133
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 assess the total daily energy expenditure as measured by doubly labeled water, and describe its components in home-living underweight patients with severe COPD.
Inclusion Criteria:
  • Severe and stable COPD, diagnosed as FEV1 < 50% predicted as determined by criteria from the European Respiratory Society
  • All lived at home and none were involved in any rehabilitation activities during study period
Exclusion Criteria:
  • BMI > 20
  • Active smoking
  • Having external help at home
  • Oxygen treatment
  • Cancer
  • Diabetes mellitus
  • Hypothyroidism
  • Other major diseases
Description of Study Protocol:


All patients recruited consecutively from the outpatient COPD unit at the Department of Respiratory Medicine, Sahlgrenska University Hospital, Goteborg, Sweden.  Of 15 asked to attend, 5 declined.


Cross-Sectional Study.

Blinding used (if applicable)

Not applicable.

Intervention (if applicable)

Not applicable.

Statistical Analysis

Results described individually and as median and range.  Statistical method described by Bland and Altman was used to assess the degree of agreement between estimated and measured BMR.

Data Collection Summary:

Timing of Measurements

BMR was measured prior to study, other measurements made on 10 standardized occasions during 15 days for each patient.

Dependent Variables

  • Body height, weight, BMI
  • Body composition through DEXA
  • Lung function measured through spirometry, arterial blood gases and diffusion capacity of carbon monoxide
  • BMR measured by indirect calorimetry
  • Total daily energy expenditure measured using doubly labeled water
  • Urine analysis by isotope ratio mass spectrometry
  • Dietary intake recorded for 7 days and through interview
  • Physical activity pattern assessed through interview and Zutphen physical activity questionnaire

Independent Variables

  • Home-living COPD

Control Variables


Description of Actual Data Sample:

Initial N: 10 patients, 5 men, 5 women

Attrition (final N):  10

Age:  median age 66 years

Ethnicity:  not mentioned

Other relevant demographics:


Location:  Sweden


Summary of Results:

Other Findings

Measured BMR was higher than predicted in 5 (4 men, 1 woman) of 10 patients using WHO equations.

Using disease-specific equations, estimated BMR was higher for male, but not for female COPD patients.

The best estimation of BMR resulted from prediction including fat-free mass.

Total daily energy expenditure varied considerably between 5,200 and 11,100 kJ.

Physical activity level ranged from 1.15 to 1.80.

Energy intake varied between 4,500 and 9,100 kJ.

In underweight patients with severe COPD, total daily energy expenditure is highly variable, ranging from 110 to 200 kJ/kg body weight.


Author Conclusion:
Among underweight patients with COPD living at home, there is great variation in total energy expenditure, physical activity, energy intake and BMR.  There are very few data concerning energy expenditure in female patients with COPD and this is the first time total daily energy expenditure in women with COPD are described.  Energy requirements in the patient group cannot solely be calculated from prediction equations.  BMR should be measured and physical activity level assessed.
Funding Source:
Reviewer Comments:
Measurements not made during same time period.  Small sample size.  1 person did not meet inclusion/exclusion criteria and was included anyway.
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? ???
  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? ???
  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? ???
  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? N/A
  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? 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