COPD: Effectiveness of Therapies (2007-2008)


Thorsdottir I, Gunnarsdottir I. Energy intake must be increased among recently hospitalized patients with chronic obstructive pulmonary disease to improve nutritional status.  J Am Diet Assoc 2002;102(2):247-249. 

PubMed ID: 11846120
Study Design:
Non-Randomized Controlled Trial
C - Click here for explanation of classification scheme.
Quality Rating:
Negative NEGATIVE: See Quality Criteria Checklist below.
Research Purpose:
The aim of this study was to investigate energy and nutrient intake as well as nitrogen balance among patients with COPD recently admitted to the hospital.
Inclusion Criteria:
COPD, admitted to the Department of Lung Medicine, Landspitali-University Hospital, Reykavik, Iceland. The reason for hospitalization was to treat exacerbation of the disease.
Exclusion Criteria:
None specified.
Description of Study Protocol:


Patients were randomly selected from the inpatient population of COPD patients admitted for an exacerbation of their disease.

Design  A full nutrition assessment was conducted upon admission and after 7 to 10 days of hospitalization. Full nutrition assessment included 7 measurements - anthropometric and and biochemical and malnutrition was defined as having 3 or more of these parameters below reference value. For all patients, 4-day weighed food records were completed beginning on the fourth day of hospitalization.

Blinding used (if applicable):  Not applicable

Intervention (if applicable)

  • Full nutrition assessment which included 7 measurements - anthropometrical and biochemical
  • 4 day weighted food record
  • Basal Energy Expenditure was estimated using a version of the Harris-Benedict equation.
  • Nitrogen balance was calculated from information on nitrogen intake and total nitrogen excretion in urine

 Statistical Analysis

Median and interquartile ranges (25 to 75th percentiles) were used to describe the data. The Wilcoxon matched pair signed rank sum test was used to assess any significant changes in nutritional parameters measured. Significance was defined as p<0.05.

Data Collection Summary:

Timing of Measurements

Full nutrition assessment was conducted upon admission and after 7- 10 days of hospitalization.  Food records were completed beginning on the 4th day of hospitalization.  24 hour urine collections were obtained during the time of weighed food recording, beginning on the fifth day of hospitalization.

Dependent Variables

  • Energy intake (measured by weighed food records) 
  • Body mass index (height and weight measurements) 
  • Triceps skinfold thickness
  • Mid-arm muscle circumferance
  • Biochemical measurements
  • Nitrogen balance

 Independent Variables

  • Nutritional status - malnutrition was defined as  having 3 variables below reference

Control Variables


Description of Actual Data Sample:

Initial N: 10

Attrition (final N): 10 (6 women, 4 men)

Age: Average age 72 years (range 62-89)

Ethnicity: Not mentioned

Other relevant demographics: 8 were taking corticosteroids, 2 were taking diuretics

Anthropometrics: 3 were identified as malnourished upon admisson, same 3 patients were identified as malnourished 7-10 days later

Location: Reykjavik, Iceland


Summary of Results:


Table 1. Energy and macronutrient intake in patients with COPD (N=10), estimated from 4 days of weighed food records
  Median 25% 75%
Energy (kcal/day) 1,820 1,560 1,996
Protein (g/day) 90 76 98
Protein (E%)a 19 18 22
Fat (g/day) 65 57 78
Fat (E%)a 33 31 35
Carbohydrate (g/day) 215 177 227
Carbohydrate (E%)a 46 46 49
[a] Percent of total energy intake.

Table 2. Nitrogen balance and energy intake calculated as percentage of basal energy expenditure (N=10)
Patient no. Sex a Age (years) BMI b FEV1% N-balance g/24 hours Energy intake/basal energy expenditure c×100
1 F 62 18,7 18 2.3 160%
2 M 63 17,2 18 −0.7 222%
3 M 70 22,7 32 −3.2 145%
4 F 75 32,9 31 −4.0 132%
5 F 73 22,0 15 1.1 126%
6 M 89 22,6 68 2.0 145%
7 F 77 29,2 45 −5.1 154%
8 F 63 19,9 37 −5.2 107%
9 F 82 26,7 44 3.5 134%
10 M 66 26,0 25 d 122%
[a] F=female; M=male.
[b] BMI=Body Mass Index.
[c] Estimated using the Harris-Benedict equation.
[d] Data missing.

Other Findings

There were no significant changes in body mass index. triceps skinfold thicknes and mid-arm muscle circumferance or area during the first 10 days of hospitalization; there were also no changes in any biochemical variables measured.


Author Conclusion:
The results of our study indicate that daily food intake of patients with COPD providing 140% of basal energy expenditure and 1.2 g protein/kg body weight was sufficient to avoid protein loss. Energy intake of malnourished patients with COPD should be increased above 140% of predicted basal energy expenditure and protein intake should be at least 1.2 g protein/kg body weight.
Funding Source:
University/Hospital: Landspitali University
Reviewer Comments:
  • Effect of corticosteroids on nitrogen balance?
  • Effect of diuretics on weight
  • Did not state which biochemical tests were performed
  • Did not state what reference variables were for the definition of malnutrition
  • Was 7-10 days an adequate time period to see patient switch from malnutrition to adequate nutritional 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) Yes
  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) Yes
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? ???
  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? ???
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? ???
  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.) ???
  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? ???
  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? ???
  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? ???
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? ???
  6.6. Were extra or unplanned treatments described? ???
  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? ???
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? ???
  7.5. Was the measurement of effect at an appropriate level of precision? ???
  7.6. Were other factors accounted for (measured) that could affect outcomes? ???
  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? ???
  8.1. Were statistical analyses adequately described and the results reported appropriately? ???
  8.2. Were correct statistical tests used and assumptions of test not violated? ???
  8.3. Were statistics reported with levels of significance and/or confidence intervals? ???
  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)? Yes
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? No
  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? ???
9. Are conclusions supported by results with biases and limitations taken into consideration? No
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? No
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