MNT: RDN in Medical Team (2015)


Morisset A-S, Côté JA, Michaud A, et al. Dietary intakes in the nutritional management of gestational diabetes mellitus. Can J Diet Pract Res Publ Dietit Can Rev Can Prat Rech En Diététique Une Publ Diététistes Can. 2014;75(2):64-71

PubMed ID: 24897011
Study Design:
Non-Randomized Controlled Trial
C - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
To examine changes in energy intake and percentage of enegy from macronutrients in reponse to nutritional intervention in women with gestational diabetes mellitus (GDM).
Inclusion Criteria:
Pregnant women at the CHU de Quebec.
Exclusion Criteria:
Pre-existing type 1 or type 2 diabetes and nutritional intervention started early in pregnancy.
Description of Study Protocol:


Pregnant women were recruited from March 2008 to September 2009 at the CHU de Quebec. No other details were provided.


  • Non-randomized controlled trial involving pregnant women with GDM and without GDM (Control Group)
  • GDM patients received special nutritional intervention (see below), whereas the control patients recieved a 30-minute RD visit with nutritional advice based on Eating Well with Canada's Food Guide and the National Guidleines for the Childbearing Years.

Blinding Used
Not applicable.


Within two weeks of positive GDM diagnosis, women were followed by a multi-disciplinary team (endocrinologist, registered dietitian, nurse, obstetrician).

  • The RD led 90-minute group session provdiing basic nutritional principles for treatment of GDM and glycemic control
  • Patients then met the RD for a 75-minute individual session to prescribe diet (40% to 45% carbohydrate, 20% to 25% protein, 30% to 35% fats) based on nutrition needs. Patients were directed to follow the dietary plan and record pre- and post-meal glycemia.
  • Patients had a variable number of follow-up visits (mean, 3.9±2.8) according to lack of success in glycemic control. Sessions were patient-centered (focused on understandings, feelings and worries), without use of specific counseling techniques.
  • Insulin therapy was initiated per the endocrinologist's decision if glycemic control was not achieved (FBG at least 5.3mmol per L or two-hour post-prandial glucose at least 6.7mmol per L)
  • All health professionals on the team provided guidance on physical activity.

Statistical Analysis

  • Student's T-tests: Compared characteristics between GDM and control patients, as well as FFQ data in pregnant women
  • Spearman correlation coefficients: Measured associations between nutrient intkaes from FFQ and three-day food records
  • Paired T-tests: Identified differences in macronutrient intakes and sugar intake (glucose, fructose, sucrose) between pre-intervention, post-intervention and postpartum time points
  • Repeated measures ANOVA: Tested time-by-group interactions for total energy intakes in terms of percentage from macronutrients and sugar intake
  • Wilcoxon tests: Compared pre- and post-intervention rates of gestational weight gain between groups.
  • Statistical analysis was performed using JMP statistical software 7.0 (SAS Institute).
Data Collection Summary:

Timing of Measurements

Baseline (at 26.9±3.8 weeks of pregnancey) and six weeks post-intervention (at 32.6±0.6 weeks of pregnancy).

Dependent Variables

  • FFQ nutrient intake: Macronutrients, lipds, omega FA, fiber, fructose, glucose, vitamin D, calcium, iron; collected from FFQ (perviously validated with health French Canadians)
  • Three-day food record nutrient intake: Same nutrient data collected on two weekdays and one weekend
  • Total gestational weight gain: Difference between maternal weight at delivery or last prenatal visit (at or after the 37th week) and self-reported pre-pregnancy weight
  • Pre-intervention rate of weight gain
  • Post-intervention rate of weight gain
  • Maternal characteristics (age, parity and pre-pregnancy weight)
  • Height and weight.

Independent Variables
Time and group (GDM vs. Control).

Control Variables
None stated.

Description of Actual Data Sample:
  • Initial N: 48
  • Attrition (final N): 44 (17 positive diagnosis of GDM and 27 normal glucose tolerance controls); 8% attrition
  • Age: 30.4±4.3 years (32 years for the GDM Group and 29 years for the Control Group)
  • Ethnicity: 47 white and one black women
  • Other relevant demographics: Four had GDM in previous pregnancy.


  • Pre-pregnancy BMI
    • Overall: 26kg/m2
    • GDM Group: 25.8kg/m2
    • Control Group: 24.2 kg/m2.
  • Gestational weeks at time of screening: 26 weeks.

Quebec, Canada.

Summary of Results:

Key Findings


GDM Group

Control Group

Statistical Significance of Group Difference

Total Energy Intake (kcal/day)

- 435±184

+ 375±212


Percentage Energy from CHO


+ 4.8±1.8%


Percentage Energy from PRO +4% (graph estimate) +0.5% (graph estimate) P<0.001
Total CHO Intake (g/day) - 73.2±23 +72.7±32.8 P<0.001
Glucose Intake (g/day) - 10.7±4.2 + 19.3±5.1 P<0.001
Rate of Gestational Weight Gain - Pre (kg/week) + 0.61±0.27 + 0.30±0.27 P<0.05
Rate of Gestational Weight Gain - Post (kg/week) +0.1 +0.15 P<0.05

Other Findings

  • Overall after the intervention, women consumed 21.9±2.4% of total energy from protein, 41.9±4.5% from carbohydrates and 36.2±4.7% from fat
  • A number of GDM patients with a percentage of energy from carbohydrates not exceeding 45% increased from six (35%) to 12 (71%; P<0.05)
  • The GDM Group reduced an average of 0.6 servings of refined grains (P<0.05) and 1.3 servings of fruit juice (P<0.001) by post-intervention.
Author Conclusion:
  • Nutritional treatment in women with GDM results in significantly reduced energy and carbohydrate intakes
  • Key message: Women with GDM should be encouraged to reduce simple carbohydrate intake and target macronutrient goals should be 40% to 45% of energy from carbohydrates, 20% to 25% from protein and 30% to 35% from fats.
Funding Source:
Canadian Institutes of Health Research and FOnds de la rechercher en sante du Quebec
Reviewer Comments:
Author-highlighted limitations:
  • Small sample size
  • Gucose self-monitoring data was not available on all patients
  • There was no documentmentation of changes in physical activity or macronutrient composition according to each meal and snack.
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? ???
  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) 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? No
  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? Yes
  4.4. Were reasons for withdrawals similar across groups? ???
  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? No
  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.) 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? ???
  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? No
  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? 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)? 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? 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