EAL

GDM: Medical Nutrition Therapy (2008)

Citation:

Sunsaneevithayakul P, Kanokpongsakdi S, Sutanthavibul A, Ruangvutilert P, Boriboohirunsarn D, Keawprasit T, Tantawattana R. Result of ambulatory diet therapy in gestational diabetes mellitus. J Med Assoc Thai. 2006 Jan; 89(1): 8-12.

PubMed ID: 16583574

Study Design:

Prospective Cohort Study

Class:

B - Click here for explanation of classification scheme.

Quality Rating:

NEUTRAL: See Quality Criteria Checklist below.

Research Purpose:

To evaluate the effectiveness of an ambulatory program for glycemic control of women with gestational diabetes mellitus (GDM).

Inclusion Criteria:

GDM diagnosis:
- Pregnant women with at least one risk factor for diabetes were screened with 50g one-hour glucose challenge test at first visit, 24 weeks to 28 weeks and 32 weeks to 34 weeks gestation
- If plasma glucose was 140mg per dL or more, OGTT was done a week later
- National Diabetes Data Group Criteria was used for diagnosis that at least two values were elevated.
OGTT higher than 105.

Exclusion Criteria:

None specified.

Description of Study Protocol:

Recruitment

Women with GDM diagnosed at Siriraj Hospital (Bangkok, Thailand) from August 1, 2003 to August 31, 2004.

Design

A total of 33 women attended weekly ambulatory care for diet therapy with their family. FBS and two-hour post-prandial blood glucose were monitored every visit for a few weeks. At the end of the program, those with poor glycemic control were admitted for a three-day intensive diet therapy, after which insulin was started if glycemic control remained poor.

Intervention

Ambulatory program: Instructed every week for a few weeks by trained diabetes nurse educators and physicians. Topics included diet therapy, pathophysiology of diabetes and antenatal management
If FBS is 105mg per dL or more or two-hour post-prandial blood glucose of 120mg per dL or more at the end of the ambulatory program, the patient was hospitalized for three-day intensive diet therapy
If FBS is 105mg per dL or more or two-hour post-prandial blood glusoce of 120mg per dL or more after intensive diet therapy, insulin was administered.

Statistical Analysis

None were specified. Descriptive statistics provided on number (percentage) of individuals receiving each component of the intervention.

Data Collection Summary:

Timing of Measurements

Every visit (weekly).

Dependent Variables

Fasting blood sugar (FBS) and two-hour post-prandial blood glucose were measured every visit
Poor glycemic control was defined as FBS of 105mg per dL or more or two-hour post-prandial blood glucose of 120mg per dL or more.

Independent Variables

Ambulatory program: No mention of adherence measures or attendance
Three-day inpatient intensive diet therapy if blood glucose was poorly controlled after ambulatory program
Insulin: If blood glucose was poorly controlled after a three-day intensive diet therapy.

Description of Actual Data Sample:

Initial N: N=4,040 cases screened for GDM. GDM is diagnosed in 317 cases, with 54 meeting inclusion criteria; 33 of 54 cases attended an ambulatory program
Attrition (final N): N=33 subjects
Location: Siriraj Hospital in Bangkok Thailand.

Summary of Results:

Variables

FBS Less Than 105mg per dL and Post-prandial Less Than 120mg per DL

N (Percentage)

FBS 105mg per dL or More

N (Percentage)

Blood glucose after ambulatory program (N=33)

14 (42.4)

19 (57.6)

Blood glucose after intensive diet therapy (N=19)

6 (31.6)

13 (68.4)

Other Findings

After intervention, 60.6% (N=20) were classified as A1 and did not require insulin therapy. The remaining 39.4% were classified as A2 and required insulin.

Author Conclusion:

The ambulatory diet therapy program was beneficial for the management of GDM patients. Hospital admission could be avoided in 42% and insulin was not required in 60% of cases after the ambulatory program alone or in combination with three-day intensive diet therapy.

Funding Source:

Reviewer Comments:

No control/comparison group
No demographic information
No attempt to identify predictors of program success
Little description of diet therapy or adherence measures (i.e. length was a "few" weeks, number or duration of visits not specified)

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?		???
	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?	No
	2.4.	Were the subjects/patients a representative sample of the relevant population?	???
3.	Were study groups comparable?		No
	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")?	N/A
4.	Was method of handling withdrawals described?		Yes
	4.1.	Were follow-up methods described and the same for all groups?	N/A
	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?	N/A
	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?		N/A
	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.)	N/A
	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?		No
	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?	???
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	No
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	No
	6.6.	Were extra or unplanned treatments described?	No
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	N/A
	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?	N/A
	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?	No
	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?		No
	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?	N/A
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	No
	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?	N/A
	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?	No
	10.2.	Was the study free from apparent conflict of interest?	Yes