COPD: Bone Density (2008)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To assess the use of inhaled corticosteroids on markers of bone formation in COPD patients.
Inclusion Criteria:
  • COPD patient
  • Male gender
  • Ambulatory
  • Moderate to severe airway obstruction
  • History of tobacco smoking
Exclusion Criteria:
  • Female gender
  • Disease of bone metabolism
  • Malignancy
  • Diabetes mellitus
  • Chronic renal failure
  • Hyperparathyroidism
  • Hyperthyroidism
  • History of bone fractures
  • Long-term use of oral anticoagulants
  • Alcoholism
Description of Study Protocol:

Recruitment:  Patients from study center recruited by unspecified techniques

Design:  Cross sectional study

Blinding used (if applicable):  Not applicable

Intervention (if applicable):  Not applicable

Statistical Analysis:  Student's t-tests were used to assess significant differences between groups and linear regression to assess correlations.

 

Data Collection Summary:

Timing of Measurements

Completed during the fall.

Dependent Variables:

  • Osteocalcin measured with lab-specific radioimmunoassay
  • Serum alkaline phosphatase, calcium, and inorganic phosphorus by Ciba-Corning Express automated blood chemistry analyzer

Independent Variables

  • Age
  • BMI
  • Average tobacco use
  • Dose and duration of corticosteroid use or control

Control Variables

  • FEV1 measured by spirometry
Description of Actual Data Sample:

Initial N: 65 males COPD patients (35 control, 30 treatment), 20 healthy subjects

Attrition (final N):  as above


Age:  Approximately 55-65 years

Ethnicity:  Turkish patients assumed, not explicitly stated

Other relevant demographics:

Anthropometrics:  Age and BMI of Control COPD, Treatment COPD, and Healthy Subjects were not significantly different.

Location:  Center for Pulmonary Disease and Thoracic Surgery, Kecioren, Ankara, Turkey

 

Summary of Results:

 

DEPENDENT VARIABLE CONTROL GROUP TREATMENT GROUP HEALTHY SUBJECTS STATISTICAL SIGNIFICANCE
Osteocalcin (ng/mL) 7.03±0.19 3.74±0.12 11.26±.0.42 p<0.01 control versus treatment,
p<0.01 control and treatment versus healthy subjects
Serum calcium (mg/dL) 8.63±0.03 8.43±0.03 9.04±0.16  NS
Serum phosphatase (mg/dL) 2.67±0.03 2.95±0.02 3.21±0.12  NS
Alkaline phosphatase(U/L) 167.91±1.49 168.17±1.60 164.81±2.81  NS

Other Findings

No strong (significance not reported) correlations among daily dosage, total intake, or duration of intake of beclomethasone and osteocalcin levels.

Author Conclusion:

  • Long-term inhaled corticosteroid, beclomethosone taken regularly in clinical doses strongly reduces serum osteocalcin levels in COPD patients.
  • Emphasized that COPD (versus asthmatics studied in previous research) and long-term tobacco use were associated with reduced serum osteocalcin levels in comparison with healthy subjects.
  • Physicians should closely monitor patients on long-term inhaled steroid use for signs of osteoporosis.
Funding Source:
Reviewer Comments:
Recruitment methods unclear.
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? No
  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? No
  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? No
3. Were study groups comparable? ???
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) ???
  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? ???
  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.) ???
  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? N/A
  4.1. Were follow-up methods described and the same for all groups? N/A
  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%.) N/A
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? N/A
  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? 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.) ???
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? ???
  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? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  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? 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? ???
  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? N/A
  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? ???
  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? ???
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? 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? ???
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? 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