COPD: Determination of Energy Needs (2007)


Vermeeren MA, Schols AM, Wouters EF.  Effects of an acute exacerbation on nutritional and metabolic profile of patients with COPD.  Eur Respir J 1997;10(10):2264-9.

PubMed ID: 9387951
Study Design:
Longitudinal Study
C - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
To investigate the effect of an acute exacerbation on the nutritional and metabolic profile of patients with COPD.
Inclusion Criteria:
  • COPD defined according to criteria of American Thoracic Society.
  • All patients were current or ex-smokers
Exclusion Criteria:
  • None had evidence of significant reversibility (>15% of predicted baseline) of air flow obstruction after terbutaline inhalation
  • Patients with concomitant diseases such as diabetes mellitus, lung carcinoma, thyroid and cardiovascular disease
Description of Study Protocol:


Consecutive patients with an acute exacerbation of COPD acutely admitted to the respiratory unit of the University Hospital Maastricht for standardized medical treatment.


Longitudinal Study.

Blinding used (if applicable)

Not applicable.

Intervention (if applicable)

Not applicable.

Statistical Analysis

Groups were compared by ANOVA or by the Mann-Whitney U test where appropriate.  The chi-squared test was used to compare categorical variables.  Changes within the patient were compared using paired t tests.

Data Collection Summary:

Timing of Measurements

Dietary intake, REE, body composition and disease symptoms assessed on admission, daily throughout the hospitalization period, at discharge, and 3 months thereafter in stable clinical condition.

Dependent Variables

  • Dietary intake measured through dietary records and diet history with cross-check 
  • Resting energy expenditure measured through indirect calorimetry
  • Diet-induced thermogenesis assumed at 10%
  • Body composition measured through bioelectrical impedance spectroscopy
  • Disease symptoms measured through visual analogue scale 

Independent Variables

  • Acute exacerbation

Control Variables


Description of Actual Data Sample:

Initial N: 23 patients

Attrition (final N):  23, 12 men, 11 females, 10 in follow-up after 3 months

Age:  mean age 63 +/- years

Ethnicity:  not mentioned

Other relevant demographics:  mean BMI was 23, range 16 - 29

Anthropometrics:  Follow-up group tended to have better lung function and weighed more than patients not followed after 3 months, no significant differences in baseline characteristics were found between groups.

Location:  The Netherlands


Summary of Results:

Other Findings

Dietary intake, since aggravation of disease symptoms, prior to admission (5640 +/- 2671 kJ) was significantly lower than habitual intake (7863 +/- 2005 kJ).

The balance between dietary intake with measured REE and estimated diet-induced thermogenesis was severely impaired during the first 3 days of hospitalization, stabilizing thereafter to 145 +/- 24% at discharge.

REE decreased from 6812 +/- 900 kJ (123 +/- 11%) on admission to 6196 +/- 795 kJ (113 +/- 14%) at discharge (p < 0.001).  Changes in REE were not related to changes in body temperature.

Measured REE was also compared to Harris-Benedict equations and was 123% +/- 11% the day after admission and 113% +/- 14% at discharge (p < 0.001).

During treatment, no significant shift in water compartments, fat-free mass and body weight was seen.

In 10 patients, 3 months after admission, dietary intake was not significantly different from usual dietary intake (8512 +/- 2290 and 8415 +/- 2600 kJ, respectively), REE was similar to the value at discharge, and a significant body weight gain was seen.  

Author Conclusion:
Our data indicate that protein intake should be increased (1.5 g/kg/day) in order to provide optimal conditions from a nutritional point of view, for protein synthesis in the recovery period.  Despite insignificant changes in body weight during hospitalization, improved body weight in the subgroup of patients that were studied 3 months afterwards, suggests the presence of a pre-existing period of energy imbalance in association with the acute exacerbation.  We conclude that an acute exacerbation of COPD is accompanied by an impaired energy balance due to a decreased dietary intake and an increased REE.
Funding Source:
Reviewer Comments:
Only 10 were followed up after 3 months, but baseline characteristics not different between subgroups.
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) Yes
  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.) 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? N/A
  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? 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? 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)? 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