SCI: Preventing Overweight (2007)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To determine the body composition differences of men with spinal cord injury and age, height and ethnicity-matched able-bodied men using 2 different dual-energy X-ray absorptiometry densitometers.
Inclusion Criteria:
  • Males with SCI who were unable to ambulate or bear weight with their legs
  • Able bodied males age, height, and ethnicity-matched with SCI males
Exclusion Criteria:

None given.

 

Description of Study Protocol:

Recruitment

SCI subjects were a part of the Rehabilitation Research and Training Center on Aging with Spinal Cord Injury; age, height and ethnicity matched controls were selected from the Body Composition Unit data banks of St Luke's Roosevelt Hospital, NY.

Design

Comparison of body composition (by DEXA) of tetraplegic and paraplegic males with SCI with able bodied controls matched for age, height and ethnicity.

Blinding used (if applicable):  not applicable. 

Intervention (if applicable):  not applicable. 

Statistical Analysis

  • ANOVA (with Scheffe's post hoc analyses) to determine significant differences between the SCI and the 3 ethnic groups for bone mineral content (BMC), lean and fat tissue mass, and percent
  • Chi square analysis to determine differences between older and younger subjects for body composition variables
  • Multiple-regression analysis to determine the associations of duration of injury (DOI), controlling for effect of age, on the body composition variables
  • Analysis of covariance to determine relationship of age with various body composition parameters in tetraplegia, paraplegia, and control groups.

 

Data Collection Summary:

Timing of Measurements

One time measurement.

 Dependent Variables

  • Regional and total body BMC measured by DEXA (SCI by Hologic QDR-2000; controls by Lunar Expert)
  • Lean tissue mass (same as above)
  • Fat tissue mass (same as above)
  • Weight on a wheelchair for the SCI group; on a standard weight scale for the control group

Independent Variables

  • SCI

Control Variables

  • Age
  • Height: self-reported by SCI group; measured in a standing position by control group
  • Ethnicity

 

Description of Actual Data Sample:

Initial N: 133 males with SCI (66 with tetraplegia and 67 with paraplegia); 100 male control subjects

Attrition (final N): no attrition reported

Age: mean 37 years for paraplegic subjects; 40 for tetraplegic subjects; 44 for controls

Ethnicity:

  • Caucasian: 32 SCI, 19 control
  • African American: 11 SCI, 6 control
  • Latino: 90 SCI, 75 control

Other relevant demographics: none provided

Anthropometrics:

  • Height: mean of 1.74 m for paraplegic subjects; 1.77 for tetraplegic subjects; 1.72 for controls
  • Weight: mean of 78.3 kg for paraplegic subjects; 79.2 for tetraplegic subjects; 82.8 for controls
  • See results

Location: SCI (Rancho Los Amigos National Rehabilitation Center, Downey, CA); Controls: St. Luke's-Roosevelt Hospital, New York, NY

 

Summary of Results:

 Table 1: Regional and total body composition (means ± SE)

Variables

Tetraplegia Group

n= 66

Paraplegia Group

n= 67

Control group

n = 100

p value

ARM:

     

 

  Lean (kg)

 4.94 ± 0.01

7.28 ± 0.02

 7.17 ± 0.01

 p< 0.005 (tetra vs para)

  Fat (kg)

 3.16 ± 0.02

3.23 ±  0.02

 1.63 ± 0.01

 p<0.005 tetra vs control; p<0.01 para vs control

 

  BMC (g) 331 ± 13 436 ± 9 442 ± 7  p= 0.05 tetra vs para
LEG:        
  Lean (kg) 12.31±0.04  11.69 ± 0.03  20.18 ± 0.03  p<0.005 tetra vs control;p0.01, para vs control
  Fat (kg) 8.24 ± 0.04  8.27 ± 0.04  5.91 ± 0.04 p<0.005 tetra vs control;p<0.01, para vs control
  BMC (g) 558 ± 32   6.06 ± 29  1,203 ± 19  p<0.005 tetra vs control;p0.01, para vs control
TRUNK:        
  Lean (kg)  25.00 ± 0.06 26.88 ± 0.05  27.49 ± 0.04  p<0.005 tetra vs control;p<0.01, para vs control
  Fat (kg) 12.77 ± 0.09  12.37 ± 0.08 10.34 ± 0.06  none
  BMC (g) 539 ± 20  572 ± 17  883 ± 17   p<0.005 tetra vs control;p0.01, para vs control
TOTAL BODY:        
  Lean (kg) 42.26 ± 1.00 45.85 ± 0.09  58.52 ± 0.08  p<0.05 tetra vs para; p<0.01, para vs control
  Fat (kg) 24.11 ± 1.34  23.86 ± 1.42 18.74 ± 1.08  p<0.005 tetra vs control;p0.01, para vs control
  BMC (g) 1,437 ± 58  1,615 ± 46  3,030 ± 44  p<0.005 tetra vs control;p0.01, para vs control

Other Findings

Advancing age was strongly associated with less lean mass and greater adiposity in those with SCI, whereas it was mildly related in the controls.

Author Conclusion:

Independent of age, total body and regional lean mass were lower and fat mass was higher in persons with SCI compared with controls

Funding Source:
Government: Dept. of Veterans Affairs
University/Hospital: Veterans Affairs Medical Center, Mount Sinai
Not-for-profit
0
Foundation associated with industry:
Reviewer Comments:
  • Authors attempted validation of DEXA instruments by subjecting two able-bodied controls to both instruments, and found significant variability between the instruments.
  • Results cannot be generalized, as women were not included in the analysis
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) ???
  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? No
  2.2. Were criteria applied equally to all study groups? N/A
  2.3. Were health, demographics, and other characteristics of subjects described? No
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
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) Yes
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? ???
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) No
  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.) ???
  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? N/A
  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.) N/A
  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? Yes
  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? Yes
  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? N/A
  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? 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? 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? N/A
  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? ???
  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)? Yes
  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