COPD: Effectiveness of Therapies (2007-2008)

Citation:

Planas M, Alvarez J, Garcia-Peris PA, de la Cuerda C, de Lucas P, Castella M, Canseco F, Reyes L.  Nutritional support and quality of life in stable chronic obstruction pulmonary disease (COPD) patients.  Clin Nutr 2005;24(3):433-41.

PubMed ID: 15896431
 
Study Design:
Randomized Controlled Trial
Class:
A - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
To evaluate the effect of 2 levels of energy intake on quality of life in stable depleted COPD outpatients, and second to evaluate the efficacy of nutritional repletion on other clinical variables (body weight, body composition, lung function, and handgrip strength) and on the compliance of previously planned daily energy intake.
Inclusion Criteria:
  • Stable COPD patients with a BMI < 22, fat-free mass index < 16, and/or a recent involuntary weight loss (>5% during last month, or >10% during the last 3 months)
  • Fulfilled criteria for COPD according to ATS guidelines
Exclusion Criteria:
  • Signs of an airway infection
  • Concomitant confounding diseases such as malignant disorders, recent surgery, GI, cardiovascular, neurological or endocrine disease
  • Treated with oral steroids, immunosuppressors or oxygen therapy at home
  • Receiving nutritional supplements
Description of Study Protocol:

Recruitment

Consecutive depleted patients with stable COPD.

Design

Randomized Controlled Trial.

Blinding used (if applicable)

Not used.

Intervention (if applicable)

  • Patients were encouraged to ingest total daily defined energy intake, either 1.7 or 1.3 REE based on Harris-Benedict for 12 weeks
  • Energy intake was achieved with regular food and if necessary, oral nutritional supplement rich in proteins (50% whey protein), with predominance of carbohydrates over fat, and enriched in antioxidants

Statistical Analysis

For categorical variables, absolute frequencies and percentages used.  Significant differences evaluated using Student's t test in normal distribution and Wilcoxon's sum test or Mann-Whitney U test when not normally distributed. 

Data Collection Summary:

Timing of Measurements

 Variables assessed before the nutritional intervention and after 12 weeks.

Dependent Variables

  • Quality of life measured by Spanish version of Chronic Respiratory Disease Questionnaire
  • Body weight, height, triceps skinfold thickness, mid-arm muscle circumference
  • Body composition measured using bioelectrical impedance
  • Lung function:  FEV1 calculated from flow-volume curve using spirometry
  • Handgrip strength measured using Harpenden handgrip dynamometer

Independent Variables

  • Total energy intake of 1.7 or 1.3 REE for 12 weeks based on Harris-Benedict
  • Dietary intake assessed using 3 day food records

Control Variables

 

Description of Actual Data Sample:

Initial N: 28 outpatients with COPD, 15 in Group A (1.7 REE), 13 in Group B (1.3 REE)

Attrition (final N):  24; 14 in Group A (1.7 REE), 10 in Group B (1.3 REE)

Age:  Group A mean age:  60.8 +/- 15.2 years, Group B mean age:  58.8 +/- 19.5 years 

Ethnicity:  not mentioned

Other relevant demographics:

Anthropometrics:  No significant differences between groups at baseline

Location:  Spain

 

Summary of Results:

 

 

Group A -Baseline (n=14)

Group A - 12 weeks Group B -Baseline (n=10) Group B - 12 weeks

Total dietary intake (kcal/d)

1800 +/- 314 2609 +/- 244, P = 0.001 1749 +/- 265 2060 +/- 312, P = 0.02

Weight (kg)

55.3 +/- 8.1

58.5 +/- 9.0, P = 0.001

55.2 +/- 8.6

56.6 +/- 9.6

TSF (mm)

6.3 +/- 2.6

8.1 +/- 2.5, P = 0.009

7.7 +/- 2.5

8.0 +/- 2.1

Fat mass (kg) 14.9 +/- 4.6 17.7 +/- 5.2, P = 0.02 15.3 +/- 5.0 15.6 +/- 5.1
FFMI (kg/m2) 14.6 +/- 1.3 13.9 +/- 1.6, P = 0.02 15.0 +/- 1.8 15.6 +/- 2.3
FEV1 (% predicted) 34.2 +/- 14.6 28.3 +/- 9.7 37.3 +/- 18.5 40.4 +/- 17.7
HS (kg) 17.7 +/- 5.9 16.1 +/- 6.5 18.6 +/- 7.3 21.2 +/- 6.5

Other Findings

All patients needed oral nutritional supplements to achieve total daily defined energy intake. 

After 12 weeks of follow-up, patients in both groups significantly increased energy intake.

Patients in Group A (1.7 REE) increased body weight (P = 0.001), triceps skinfold thickness (P = 0.009) and body fat mass (P = 0.02), and decreased body fat-free mass index (P = 0.02).

In this group, a marked increase in airflow limitation was observed.

A tendency to increase body weight and handgrip strength, and to decrease airflow limitation was observed in patients from group B (1.3 REE).

Furthermore, patients in the later group showed a significant improvement in the feeling of control over the disease (P = 0.007) and a tendency to better the other criteria in a quality of life scale.

Author Conclusion:
Our results, regardless of small sample size and the lack of information on exercise compliance, contribute to suggest that in some stable depleted COPD patients a defined oral nutritional supplement to reach total daily energy intake without overfeeding could be beneficial to improve one criteria (mastery) among many others in  quality of life scale.
Funding Source:
University/Hospital: Instituto de Salud Carlos
Reviewer Comments:
Small sample size.  Authors note lack of exercise compliance.  Energy intake estimated using Harris-Benedict. 
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? 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? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) No
  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.) Yes
  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? Yes
  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? ???
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? Yes
  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? ???
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? No
  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? 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)? 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? 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