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MNT: RDN in Medical Team (2015)

Citation:

Molenaar EA, van Ameijden EJ, Vergouwe Y, Grobbee DE, Numans ME. Effect of nutritional counselling and nutritional plus exercise counselling in overweight adults: A randomized trial in multidisciplinary primary care practice. Family Practice. 2010; 27: 143-150.

PubMed ID: 20026554
 
Study Design:
Randomized Controlled Trial
Class:
A - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
  • To evaluate the efficacy of nutritional counseling by a dietitian compared with multi-disciplinary nutritional status plus exercise counseling by a dietitian and physiotherapist on weight loss in an adult overweight population
  • A secondary objective was to compare both interventions with usual care.
Inclusion Criteria:
  • Participant in the Utrecht Health Project
  • Men and non-pregnant women
  • Age 18 to 65 years
  • BMI 28kg/m2 to 35kg/m2.
Exclusion Criteria:
  • Unable to speak Dutch
  • Already treated for overweight by a dietitian or physiotherapist
  • Diagnosed with mental health problems
  • Plans to move out of the residential area shortly.
Description of Study Protocol:

Recruitment

  • Recruited from the Utrecht Health Project, an ongoing prospective cohort study
  • UHP entry data were used to select men and women who met inclusion criteria
  • General practitioners applied the exclusion criteria
  • Eligible participants were invited to participate in the study by a letter from their general practitioner
  • A third group (untreated controls) was selected from new participants of the UHP trial following the same inclusion and exclusion criteria.

Design

  • Randomized controlled trial
  • UHP research nurses conducted the computerized randomization.

Blinding Used

Implied with measurements.

Intervention

  • Nutrition counseling (D): Seven individual face-to-face counseling sessions with a dietitian during six months (Sessions four and seven fixed at, respectively, three months and six months after the first session) and one follow-up session at 12 months. Individualized attainable goals for a healthy diet and effective caloric intake reduction were set and a strategy was developed to gradually achieve a moderate sustainable weight reduction.
  • Nutritional plus exercise counseling (D+E): Nutritional counseling as for NC group plus six individual face-to-face counseling sessions with a physiotherapist during six months and one follow-up session at 12 months. Individualized attainable goals for an increase in daily physical activity were set and a strategy was developed to gradually achieve a moderate sustainable weight reduction and improve cardiorespiratory fitness, taking habitual physical activity, fitness and personal preferences into account.
  • Control group: Received usual care and were not invited to receive structure nutritional or exercise counseling by a dietitian or physiotherapist.

Statistical Analysis

  • Data were analyzed using a modified intention-to-treat approach, which included all participants that had at least one follow-up measurement
  • Continuous variables were presented as means with SD and categorical variables as percentages
  • Linear regression analyses was used to compare changes in outcomes between intervention groups (D vs. D+E)
  • Generalized estimating equations (GEE) were then applied with an autoregressive heterogeneous covariance structure to take the correlation into account between repeated outcome measures within participants. Variables included intervention assignment, time and the interaction between intervention and time.
  • The proportion of participants who achieved more than 5% of weight loss at six months and 12 months was also calculated. Differences in proportion of weight loss higher than 5% between the D and D+E group were expressed as relative risks (RR) with corresponding 95% CI.
  • Changes in weight between intervention and control groups was also compared using GEE analysis.
Data Collection Summary:

Timing of Measurements

  • Recruitment between February 2006 and October 2006
  • Measurements at zero months, six months and 12 months.

Dependent Variables

  • Height and weight; BMI
  • Waist circumference.

Independent Variables

  • D
  • D+E
  • Control.

Control Variables

 None listed.
Description of Actual Data Sample:

 Initial N

N=134 (D, 67; D+E, 67) adults.

Attrition (Final N)

  • Figure 1 of article is a good flow diagram of participants through the study
  • Six-month follow-up: D, 57; D+E, 53 (attrition rate 18%)
  • At 12-month follow-up: D, 51; D+E, 50 (attrition rate 7%)
  • Control group: Invited, 103; six months, 37; 12 months, 33
  • A total of 58% of participants in interventions groups were men; 63% in the control group were men.
  • Reasons for withdrawal:
    • Unmet expectations of treatment: D, three; D+E, three
    • Personal reasons: D, four (family circumstances, lack of time, moved, not content with randomization); D+E, seven (lack of time, moved, family circumstances)
    • Medical reasons: D, one (stressed); D+E, three (pregnant, illness)
    • Logistics: D, one
    • Unknown: D, one; D+E, one
    • Lack of motivation: D, one at 12 months.

Age

  • Interventions: Aged 43 years
  • Control: Aged 41 years. 

Ethnicity

  • Dutch:
    • Intervention groups: 77%
    • Control group: 87%.
  • Non-Dutch:
    • Intervention groups: 23%
    • Control group: 13%.

Other Relevant Demographics

  • Those who completed the study were older than participants who discontinued the study (44 years vs. 40 years)
  • Education:
    • Low:
      • Intervention groups: 15%
      • Control group: 25%.
    • Middle:
      • Intervention groups: 47%
      • Control group: 35%.
    • High:
      • Intervention groups: 39%
      • Control group: 40%.
  • Smoking:
    • Current:
      • Intervention groups: 15%
      • Control group: 13%.
    • Never:
      • Intervention groups: 49%
      • Control group: 46%.
    • Ever:
      • Intervention groups: 36%
      • Control group: 41%.

Anthropometrics

  • BMI:
    • Intervention groups: 31.0±1.9kg/m2 (D, 31.3±2.0kg/m2; D+E, 30.8±1.9kg/m2)
    • Control group: 30.2±1.9kg/m2.
  • Waist circumference:
    • D: 103.7±8.6cm
    • D+E: 104.1±7.1cm.

Location

University Medical Center Utrecht, The Netherlands.
Summary of Results:

Key Findings

  • A total of 88% of the D participants and 89% of the D+E participants visited the dietitian (D, 4.5±2.1 sessions; D+E, 4.1±2.0 sessions). Exclusion of dropouts resulted in a mean number of attended dietitian sessions of 5.0±1.9 for D and 4.4±1.9 for D+E.
  • A total of 87% of the D+E group visited the physiotherapist (5.0±2.1 sessions, without dropouts for 5.6±1.9 sessions)
  • Weight decreased significantly from baseline to six months in D [-2.2kg 95% CI (-3.1kg to -1.4kg)] and D+E [-3.0kg (-4.0kg to -2.0kg)]
  • The weight loss was maintained at 12 months in both groups [-2.0kg (-3.1kg to -1.4kg) for D; -3.1kg (-4.5kg to -1.6kg) for D+E]
  • A total of 28% (95% CI: 16 to 40) of the participants in the D+E group lost more than 5% of their baseline weight at six months, while the proportion of participants in the D group was 16% (6% to 25%). The corresponding RR of losing more than 5% weight in D+E vs. D was 1.8 (95% CI: 0.9 to 3.8).
  • At 12 months, the proportion of participants who achieved more than 5% of weight loss in the D+E and D groups were, respectively, 32% (19% to 45%) and 20% (9% to 31%), with a corresponding RR of 1.6 (1.8 to 3.2)
  • Waist circumference decreased significantly from baseline to six months in both intervention groups [-2.1cm (-3.3cm to -0.8cm) for D; -3.7cm (-5.1cm to -2.3cm) for D+E] and was sustained up to 12 months [-2.1cm (-3.5cm to -0.7cm) and -4.2cm (-6.0cm to -2.5cm), respectively]
  • Participants in the D+E group tended to have a larger reduction in waist circumference compared with those in the D group at six months [-1.6cm (-3.5cm to -0.2cm)] and 12 months [-2.2cm (-4.4cm to 0.06cm); overall P-value for interaction was 0.14].

 Other Findings

 Figure 2 of the article demonstrated the large inter-individual variation in weight change for this study.
Author Conclusion:
  • Nutritional counseling by a dietitian resulted in modest reductions of weight and waist circumference in overweight adults in a multi-disciplinary primary care setting, which were sustained up to 12 months
  • Adding exercise counseling by a physiotherapist did not significantly enhance the effect but may have additional beneficial clinical effects on waist circumference.
Funding Source:
Government: Ministry of Health, Welfare, and Sports; Province of Utrecht; Dutch Organization of Care Research
University/Hospital: University of Utrecht; University Medical Center of Utrecht; Dutch College of Healthcare Insurance Companies
Reviewer Comments:
  • Table 3 and Table 4 are a little bit confusing in the way the data is presented and designating statistical difference. The text says there was a significant weight loss at six months as shown in Table 4; however, the only P-value shown is for the interaction and is not significant.
  • Limitations as cited by the authors:
    • Attrition rate of the study (25% at 12 months) may have biased the results
    • Control group was not randomly selected
    • The trial was carried out in a multi-disciplinary primary care setting, which may not be available in all countries.
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) Yes
  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? 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? 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? 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? ???
  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? ???
  8.1. Were statistical analyses adequately described and the results reported appropriately? No
  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)? Yes
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? ???
  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