SCI: Role of the Registered Dietitian (2007)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

To assess the effectiveness of a modified weight management program on various health outcomes in persons with spinal cord injury (SCI) over a 6-month period.

Inclusion Criteria:
  • Age 19 years or older
  • Traumatic or nontraumatic SCI for more than 1 year
  • BMI > 25 kg/m2
  • Not currently enrolled in a weight loss program, receiving weight loss medication or taking medication that would influence weight change.
Exclusion Criteria:
  • Pregnancy
  • Concurrent medical conditions for which changes in exercise or diet would be contraindicated
Description of Study Protocol:

Recruitment

 Participants were recruited at the community level through the University of Alabama at Birmingham, Birmingham, Alabama from 2001 to 2003.

Design

 Four cohort groups (including the pilot test group) were established to maintain smaller intervention group sizes.

Blinding used (if applicable)

Information obtained previously was blind to data collectors at each assessment visit.

Intervention (if applicable)

  •  Weight management program including a time-calorie displacement diet which emphasized ingestion of large quantities of high-bulk, low-energy-density foods (vegetables, fruits, high-fiber grains and cereals) and moderation in high-energy-density foods (meats, cheeses, sugars, and fats).
  • Men were started at 1400 calories, women at 1200 calories.
  • Participants were prescribed the number of daily servings for five food groups (fat, meat/dairy, starch, fruit and vegetable).
  • Once a week for 12 weeks, participants and their spouses attended a 90 minute group class, lead primarily by a registered dietitian.
  • In week 6, a 30 minute exercise session of specifically designed home-based activities for persons with SCI was incorporated into each weekly class to encourage participation in physcial activity.
  • Psychologists were consulted in areas related to stress management, relaxation techniques, problem-solving, and behavior change strategies.

Statistical Analysis

  •  Paired t-tests or equivalent nonparametric method (Wilcoxon's signed rank sum test) were used to determine significance of change in health outcomes from inital to follow-up assessments.
  • Pearson's correlation analysis was used to test the association of weight change with participant's characteristics and other health outcomes. A correlation greater than 0.40 or less than -0.40 were considered as important associations regardless of the statistical significance level due to the small-scale pilot study.
  • No adjustment for multiple comparisons was made in the analysis to avoid unjustified dismissal of potentially meaningful findings.
  • A probablility of < 5% was considered to be statistically significant.
Data Collection Summary:

Timing of Measurements

  •  A face-to-face interview was conducted at the initial visit to obtain information on sociodemographic characteristics and weight history. Medical history and medication use was also obtained.
  • Data on health outcomes were collected over a 6-month period: at baseline, week 12 (immediately after intervention, and week 24 (12 weeks after interventon). 

Dependent Variables

  • Body weight measured to the nearest 0.1 kg on a scale adapted to wheelchairs
  • Height measured to the nearest 0.1 cm in a supine position with legs outstretched and feet in dorsiflexion.
  • Waist circumference to the nearest 1 mm
  • Neck circumference to the nearest 1 mm.
  • Skinfold thickness for chest, biceps, tricpes, subscapula, and suprailiac on the right side of the body.
  • Dual energy X-ray absorptiometry (DXA) to estimate fat mass, lean mass and bone mineral content
  • Blood pressure
  • Total cholesterol
  • HIgh-density lipoprotein (HDL) cholesterol
  • Low-density lipoprotein (LDL) cholesterol
  • Blood hemoglobin
  • Serum albumin
  • Usual food intake was measured by the Health Habits and History questionnaire.
  • Subjective feelings of wellness and distress were assessed by the General Well-Being Schedule.

Independent Variables

  •  Weight management program consisting of nutrition education, exercise and behavior modification

Control Variables

 None noted by author.

Description of Actual Data Sample:

 

Initial N: 17 (9 males and 8 females)

Attrition: 16 ( 9 males and 7 females)

Age:

43.8 (21.0-66.0 years)

Ethnicity:

  • White: 13 (81%)
  • African American: 3 (19%)

Other relevant demographics:

Marital status:

  • Married or living as married: 6 (37.5%)
  • Divorced: 6 (37.5%)
  • Never married: 4 (25%)

Education

  • High school graduate or less: 5 (31%)
  • Some college or technical school: 6 (38%)
  • College graduate or higher: 5 (31%)

Employment status

  • Employed full- or part-time: 6 (38%)
  • Retired: 5 (31%)
  • Student: 2 (12%)
  • Unemployed: 3 (19%)

Family history of overweight/obesity

  • Yes: 11 (69%)
  • No: 5 (31%)

Level of injury

  • Tetraplegia: 4 (25%)
  • Paraplegia 12 (75%)

ASIA Impairment Scale

  • A: 9 (56%)
  • C: 3 (19%)
  • D: 4 (25%)

Years since injury: 17.5 (1.7-60.3)

Anthropometrics

None noted by author

Location:

 Birmingham, Alabama

Summary of Results:

 Significant changes in health profile during program intervention (week 12, n=16)

Health profile variable

Initial Mean (s.d.)

Change Mean (s.d.)

Statistical Significance of Change (P)

Body weight (kg)

  97.4 (17.8)

  -3.5 (3.1)

 0.0004

Body mass index (kg/m2)

  34.3 (4.5)

  -1.3 (1.2)

 0.0005

Total fat mass (kg)

  41.4 (11.2)

  -2.9 (4.6)

 0.05

Waist circumference (cm)  117.4 (17.0)   -4.1 (5.0)  0.005
Neck circumference   42.7 (5.7)   -0.9 (1.4)  0.02
Skinfold thickness (mm)  111.4 (34.5)  -10.7 (9.7)  0.0005
HDL-cholesterol (mg/dL)  201.7 (19.3)   -3.2 (5.4)  0.03
Dietary intake of saturated fat (gm)   23.2 (10)   -8.7 (10.9)  0.006
Dietary intake of cholesterol (gm)  228.3 (99.0)  -77.2 (78.3)  0.001
Dietary intake of fiber (gm)   10.9 (4.8)    7.6 (7.2)  0.0007
Confidence of weight control     2.5 (1.1)    1.1 (1.1)  0.002
Self-rated nutritional qulaity of diet     2.3 (0.8)    0.6 (0.7)  0.002
Self-rated eating habit     2.4 (0.8)    0.6 (0.6)  0.006
Troubled by heartburn     2.3 (1.3)  -0.9 (1.2)  0.008
Difficulty transferring     3.7 (1.4)  -1.1 (1.3)  0.004
Difficulty putting on/taking off clothing     3.1 (1.3)  -0.9 (1.2)  0.02
Don't feel sexually attractive     3.3 (1.4)  -0.8 (1.1)  0.02
Self-esteem not what it should be     3.3 (1.2)  -1.0 (1.0)  0.004 

 

 Changes in health profile during postintervention follow-up (week 24, n=13)

Health profile variable

Initial Mean (s.d.)

Change Mean (s.d.)

Statistical Significance of Change (P)

Body weight (kg)

   98.2 (19.7)

   -2.9 (3.7)

 0.01

Body mass index (kg/m2)

   34.5 (4.7)

   -1.1 (1.4)

 0.01

Total fat mass (kg)

   42.1 (12.5)

   -2.2 (1.8)

 0.007

Waist circumference (cm)  117.1 (18.1)    -3.3 (5.2)  0.04
Neck circumference    42.6 (6.2)    -1.1 (2.1)  0.08
Skinfold thickness (mm)  114.1 (35.7)   -13.2 (10.6)  0.0007
Total calories (kcal/d)  1657.4 (702.0)  -315.8 (567.2)  0.07
Dietary intake of saturated fat (gm)      23.5 (10.9)    -5.6 (8.1)  0.03
Difficulty transferring       3.6 (1.5)    -1.1 (1.3)  0.02
Difficulty putting on/taking off clothing       2.9 (1.3)    -0.9 (1.0)  0.02
Don't feel sexually attractive       3.1 (1.4)    -0.8 (1.2)  0.03

Other Findings

 Baseline factors were important in determining the amount of weight reduction during the program intervention (week 12).  These included being white (r=-0.44), tetraplegic (r=-0.43), married or living as married (r=-0.67), and having greater confidence in weight control (r=-0.42); however these were not statistically significant.

Maintenance of weight below the inital level at week 24 was associated with being older (r=-0.45), of longer duration postinjury (r=-0.49), tetraplegic (r=-0.42), employed full- or part-time (r=-0.45), without family history of overweight/obesity (r=-0.46), and with lower total or LDL-cholesterol level at baseline (r=-0.53 and -0.58, respectively). Only LDL-cholesterol reached significance.

Author Conclusion:
  • A carefully planned program with time-calorie displacement dietary approach is effective for overweight/obese individuals with SCI to lose weight at an acceptable rate without compromising total lean mass and overall health.
  • The variation in the amount of weight loss by the participants suggests the importance of the flexibility of the intervention and competence of the practitioners working with diverse sociocultural and injury severity groups.
  • The cost-effectiveness of alternative methods requiring less face-to-face contact for administering intervention for weight loss deserves further investigation.
Funding Source:
Reviewer Comments:
  • Lack of control or comparison group
  • The group of SCI patients was a selective group with the education  level being relatively high.
  • Persons were precluded from the program if they could not travel to the clinic once a week for 12 weeks
  • This program may not be an ideal approach for individual excluded from the study and may need modification for socio-culturally diverse groups
  • A large variation in measurements was observed because of small sample size therefore the precision for the estimate of the effect sizes was small.
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? 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? N/A
  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? 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.) 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.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? Yes
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? Yes
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? No
  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? Yes
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? 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? 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? 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? Yes
  6.8. In diagnostic study, were details of test administration and replication sufficient? Yes
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