Pediatric Weight Management

Family-based Counseling to Reduce Childhood Overweight (2006)

Citation:

Figueroa-Colon R, von Almen TK, Franklin FA, Schuftan C, Suskind RM. Comparison of two hypocaloric diets in obese children. Am J Dis Child. 1993 Feb;147(2):160-6.

PubMed ID: 8427238
 
Study Design:
Non-Randomized Controlled Trial
Class:
C - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:
To determine whether a protein sparing modified fast is safe and effective for childhood weight loss in an outpatient weight reduction program.
Inclusion Criteria:
  1. Healthy
  2. Not taking medications
  3. Enrolled in outpatient weight loss program (convenience sample--referred to program by physician or parent)
Exclusion Criteria:
Not specified
Description of Study Protocol:

Recruitment

19 consecutive children enrolled in an outpatient weight reduction program at Children's Hospital, New Orleans, Louisiana. Referred to program by physician or parents.

Design

Subjects assigned to two groups:

  • PSMF Group: high protein, low carbohydrate, low calorie: protein sparing modified fast (PSMF)
  • Balanced Group: balanced macronutrient, hypocaloric diet.

Group membership does not appear to be randomized, but based on timing of enrollment.

Treatment Phase 1: For the first 10 weeks all subjects were placed on a hypocaloric diet (either PSMF or Balanced)

Treatment Phase 2: Subjects met with program staff once a month for a year following Phase 1.

Both groups received the same interventions with the exception of the diet during the first 10 weeks of the program.

Blinding used (if applicable)

Group leaders were blinded regarding the diet intervention.

Intervention (if applicable)

Diet

  • First 10 weeks: treatment or control diet
  • After 10 week intervention: all subjects placed on 4200 joule/day (1000 calories/day) balanced diet.
  • Energy consumption per day increased in next 3 months for all subject to 5040 joules/day (1200 calories/day).

PSMF Group:

  • 1.5-2 grams of protein per kg of weight (up to 100g) per day (providing 600-800 calories/day). Diet composition: 50% protein, 40% fat, 10% carbohydrates.
  • Foods: lean meats and sea food, non-starchy vegetables.
  • Multivitamin supplement
  • 2 liters/day of water or calorie free liquid (recommended)

Balanced Group:

  • balanced macronutient diet adapted from the American Diabetes Association exchange lists for meal planning (800-1000 calories/day: 20% protein, 30% fat, 50% carbohydrates).
  • No supplementation
  • Advised to consume "reasonable amounts" of milk and vegetables

After initial 10 week period both groups were put on a balanced diet: 20% protein, 30% fat, 50% carbohydrates, beginning at 1000 calories/day and increased to 1200 calories/day at 3 months.

Overall, during the first 70 days of treatment the PSMF group received 200 fewer calories a day than the Balanced group.

Physical Activity

Each session included a 20 minute physical activity component, beginning with a warm up and then increasing in intensity with the goal of subjects reaching 70% of their maximum heart rate (for 10 minute duration).

Children and families educated on lifestyle change related to physical activity.

Behavior Modification

  • Subjects educated in each session on a relevant topic (e.g., food preparation, family difficulties, etc.)
  • Subjects encouraged to keep dietary and physical activity diaries (reviewed by program staff weekly during the first 10 weeks).
  • Subjects discussed feelings about weight loss and general problems associated with treatment.
  • PSMF subjects were checked for the presence of ketones in urine weekly (to check for diet compliance). If no ketones were detected this was discussed during an individual family session.
  • During the maintenance phase (following the 10 weekly sessions) families met once a month with program staff. Subjects kept a 3-day food and activity diary the week before the family session. Program staff reviewed the diaries with the families.
  • Subjects were educated on stimulus control, cue elimination, behavior chains and preplanning, cognitive restructuring, alternatives to overeating.
  • Parents were educated on using incentives for weight loss and program compliance.

Family Support

  • While both parents and siblings were encouraged to participate, at least one parent was required to participate in the program.
  • Parent sessions held concurrently with child sessions, and met for one hour.
  • Parents were educated on a range of topics: food preparation, stimulus control, praise, modeling, limit setting, and consistency.
  • Parents educated on positive parenting techniques.
  • Parents encouraged to include all family members in the lifestyle change contract.

Statistical Analysis

One-way analysis of variance.

Data Collection Summary:

Timing of Measurements

  • 10 weeks
  • 6 months
  • 14.5 months

Dependent Variables

  • Weight and height (using standard scales)
  • Percent body fat (skinfold measurements)
  • Blood pressure and basline biochemical measures

Independent Variables

Diet intervention: PSMF versus Balanced diet

Control Variables

Sex

Description of Actual Data Sample:

Initial N: 19

  • PSMF: 10
  • Balanced Diet: 9

Attrition (final N):

  • All subjects on both diets completed the initial 10 week course.
  • 7 subjects from PSMF group completed the 14.5 month program (30% attrition)
  • 4 subjects fromt the Balanced group completed the 14.5 month program (56% attrition)

Age: 9-11 years

Ethnicity: not given

Other relevant demographics:

  • all children middle class (not defined)
  • between 45%-131% of ideal body weight (based on NCHS standards)
  • children not taking medications

Location: New Orleans, LA

Summary of Results:

Baseline

Diet groups did not differ (at al statistically significant level) on any baseline measurement.

Weight Changes

The table below presents the changes in weight measures (and height) comparing PSMF group and Balanced group.

Outcome

Time

PSMF Group

Change from baseline (Mean SD)

Balanced Group

Change from baseline (Mean SD)

Significance between groups

Weight (kg)

10 week

-11.2±4.4

-5.1±4.1

P<.01

6 month

-11.2±7.6

-5.8± 6.3

14.5 month

1.3± 7.0

-0.9±6.6

 

Percent Overweight

10 week

-29.5±7.4

-13.8±7.7

P<.001

6 month

-32.2±13.4

-17.5±15.2

P<.05

14.5 month

-23.3±19.2

-20.3±16.5

 

BMI

10 week

-5.2±1.3

-2.4±1.4

P<.001

6 month

-5.6±2.5

-3.0±2.6

P<.05

14.5 month

-2.5±3.1

-2.7±2.8

 

Height (cm)

10 week

0.9±0.6

0.4±0.3

 

6 month

1.7±0.7

1.2±0.6

 

14.5 month

7.2±1.4

6.1±1.3

 

PSMF group lost more weight during the initial phases of the study. While weight returned to baseline levels at 14.5 months, the percent overweight of the PSMF group remained significantly (p<.02) different from baseline at 14.5 months.

Growth Velocity

Growth velocity slowed during the period of rapid weight loss (baseline to 6 months) and then increased as the caloric intake increased.

Body Composition

At 10 weeks, the PSMF group showed a statistically greater decrease in body fat than the Balanced group (-1.1±1.0 versus -0.3±0.5 kg).

Blood Pressure

When diet groups were analyzed seperately, changes in blood pressure did not reach statistical significance. However, when the groups were combined, mean systolic and diastolic blood pressures were decreased from baseline for all time intervals.

Biochemical Factors

Biochemical factors for both groups remained within normal limits for the duration of the study. Only serum cholesterol decreased significantly from baseline to 10 weeks when diet groups were combined (4.47±0.79 mmol at baseline, 3.74±0.84 mmol at 10 weeks).

Author Conclusion:
  1. PSMF appears to be a safe and effective diet for short term weight loss in older children and adolescents in a medically supervised weight loss program.
  2. A comprehensive outpatient weight loss program is well accepted by older children, adolescents, and their parents.
  3. While growth velocity slowed during periods of weight loss, velocity increased as caloric intake increased (in the later phases of the study). According to the authors, "This indicates that greater changes in body weight do not necessarily imply greater slowing of growth velocity."
Funding Source:
University/Hospital: Unversity of Alabama at Birmingham, Childrens Hospital of Alabama, Louisiana State Medical Center, Children's Hospital of New Orleans
Reviewer Comments:

Strengths:

  • Program staff who lead treatment groups were blinded to diet group membership
  • Longer term follow-up (14.5 months)

Weaknesses:

  • Very small N
  • Subjects not randomized
  • Reasons for withdrawal not given
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? 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? No
  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? No
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? No
  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%.) No
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? No
  4.4. Were reasons for withdrawals similar across groups? No
  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? Yes
  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.) No
  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? 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? 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? 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)? No
  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? No
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? No
  10.2. Was the study free from apparent conflict of interest? Yes