MNT: Weight Management (2015)

Citation:

Villanova N, Pasqui F, Burzacchini S, Forlani G, Manini R, Suppini A, Melchionda N, Marchesini G. A physical activity program to reinforce weight maintenance following a behavior program in overweight/obese patients. Int J Obes. 2006; 30: 697-703.

PubMed ID: 16314874
 
Study Design:
Prospective Cohort Study
Class:
B - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
To assess the cumulative effects of the combination of a cognitive-behavioral therapy (CBT) program and a fitness program on regular activity and weight loss maintenance in treatment-seeking obese patients.
Inclusion Criteria:
Overweight or obese.
Exclusion Criteria:
Not reported.
Description of Study Protocol:

Recruitment

Participants volunteered for the study; recruitment methods were not otherwise reported.

Design

The study observed participants enrolled in a fitness program during a weight loss maintenance period approximately nine months after the completion of a CBT program. Participants were followed up to one year after completing the fitness program.

Intervention

  • The CBT program was based on the LEARN program for weight control. It included 12 weekly sessions, chaired by doctors and dietitians, involving groups of eight to 12 patients. Participants were taught about BMI and regular weight control, and were instructed on counting calories and monitoring daily food intake, with the use of a residual manual.
  • The fitness program included 12 bimonthly sessions, chaired by doctors and dietitians, involving groups of eight to 12 patients. The strategy to increase physical activity focused on motivation and self-efficacy, integrated with pleasure, social support and removal of barriers.
  • The initial goal of the fitness program was at least 10 to 15 minutes of lifestyle walking or brisk walking three to five times per week, with a target of 30 minutes per day of brisk walking by the end of the program. Patients were supplied with a guided self-help manual, a logbook and an electronic pedometer. 

Statistical Analysis

Differences between groups were analyzed by Student’s T-test for paired or unpaired data, whenever appropriate, and time x group, repeated measurements analysis of variance (ANOVA). 

Data Collection Summary:

Timing of Measurements

With the exception of REE, measurements were taken at baseline (beginning of CBT) and at the beginning and end of the fitness program. Additionally, pedometer measurements were recorded within one month from the beginning of CBT and weight was measured every other week of the fitness program. REE was measured at the beginning and end of the fitness program.

Dependent Variables

  • Weight history
  • Amount of daily physical activity
  • Resting energy expenditure (REE)
  • Metabolic syndrome (secondary outcome).

Independent Variables

All subjects participated in a 12-week CBT program, followed by a fitness program lasting approximately six months.

Control Variables

Presence of eating disorders.

Description of Actual Data Sample:
  • Initial N: N=257 (51 male, 206 female)
  • Attrition (final N): N=200 (36 male, 164 female); 22% dropout rate
  • Age: 46±11 years; range 20 years to 66 years.
Anthropometrics
  • 15% were overweight (BMI 25 to 29.9)
  • 37% were in class I obesity (BMI 30 to 34.9)
  • 32% in class II obesity (BMI 35 to 39.9)
  • 16% in class III obesity (BMI 40 or higher).

Location

Bologna, Italy.

Summary of Results:

Key Findings 

 
  Pre-CBT (Baseline) Pre-fitness Program End-of-fitness Program
Weight (kg) 93.7±17.5 87.4±16.1a 85.8±16.2 b
BMI 35.2±5.3 32.8±5.1 a 32.1±5.2 b
Waist circumference (cm) 102.2±12.5 -- 97.7±12.8 b
Number of steps per day 3,963±2,642 6,082±2,818 a 8,717±3,980 b
5,000 or more steps per day (percent) 24 (18 to 30) 72 (66 to 78) 84 (78 to 88)
REEc -- 1,328±219 1,428±289 b

aSignificantly different from baseline; P<0.0001
bSignificantly different from pre-fitness program; P<0.005
cMeasured in 61 cases.

 

  • The CBT produced an average weight loss of 6.7±87kg. During follow-up, there was a mild but significant weight regain compared to end-of-CBT values (+2.1kg; P<0.0001).
  • The fitness program restarted the process of weight loss in 123 (61.5%) participants; a significant decrease in weight was observed at the end of the fitness program vs. pre-fitness program (85.8±16.2kg vs. 87.4±16.1kg, P<0.005)
  • A significant increase in physical exercise, measured by number of steps per day, was observed at the end of the CBT program vs. at baseline (6,082±2,818 vs. 3,963±2,642, P<0.0001)
  • During the fitness program, activity level further increased to 8,717±3,980 steps per day (P<0.005 vs. pre-fitness program)
  • Total weight loss significantly correlated with the final number of steps per day as well as with the increase in the number of steps from baseline (P<0.0001)
  • A significant increase in REE was observed at the end of the fitness program vs. pre-fitness program (1,428±289 vs. 1,328±219, P<0.005). 

Other Findings

At the end of the CBT and fitness program, prevalence of metabolic syndrome dropped from 43.9% to 23.7% (P<0.0001).
Author Conclusion:
A specific fitness program may help patients to increase physical activity and to prevent weight regain following a CBT program.
Funding Source:
University/Hospital: University of Bologna, Bologna, Italy
Reviewer Comments:
  • Weight changes were not recorded in an identical untreated population (no control)
  • Subjects who dropped out were not systematically followed to allow comparison with treated patients
  • Subjects volunteered; they were not screened for readiness to change. Thus, high dropout rate and failure of a few subjects may stem from non-selection.
  • Known limitations of using pedometers to measure physical activity.
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? 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? Yes
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) N/A
  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? Yes
  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? Yes
  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? 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? 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? 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)? 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