GDM: Postpartum Care (2008)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
The researchers sought to determine the relationship between breastfeeding and both type 2 diabetes and gestational diabetes (GDM) in a variety of clinical contexts, with a focus on prevention.
Inclusion Criteria:
  • Each of relevant articles was reviewed by at least two of the authors.
  • All studies involved term, singleton infants unless otherwise noted.
  • All articles were selected for inclusion in the review and critically evaluated based on:

1. study design-all studies were descriptive

2. target population

3. sample size/power

4. clear definition of diabetes

5. control for confounding variables

 

Exclusion Criteria:
Exclusion criteria was not delineated.
Description of Study Protocol:

Recruitment - Medline search from 1966 - 2003.  References in bibliographies of pertinent articles and major texts also searched.  Search was limited to English language and to human subjects.  In addition, entire Cochrane database and NIH clinical trials website searched.  Specific search terms included breastfeeding, breast-feeding, breast feeding, infant nutrition and lactation.

Design: Systematic Review

Blinding used (if applicable):  not applicable

Intervention (if applicable):  not applicable

Statistical Analysis -not applicable

 

Data Collection Summary:

Timing of Measurements- not applicable

Dependent Variables- not applicable

Independent Variables- not applicable

Control Variables- not applicable

 

Description of Actual Data Sample:

Initial N: 12 of 15 studies (80%) met the selection criteria.

Attrition (final N):

Age:

Ethnicity:

Other relevant demographics:

Anthropometrics (e.g., were groups same or different on important measures)

Location: worldwide studies

 

Summary of Results:

Table I. Differences in Diagnosis Criteria for Impaired Glucose Tolerance and Type 2 Diabetes

Authors Diagnostic Criteria Reference
  Impaired Glucose (IGT)  
Job et al.,1976 Fasting Glucose>=110 mg/dL,1-hour>=160;2-hour>=120 mg/dl(after 50-g OGTT) Not specified
Plagemam et al.,2002  Fasting Glucose<140 mg/dL and 2-hour glucose>140 mg/dL(after 75g/kg OGTT)  National Diabetes Data Group,1979
   Type 2 Diabetes or NIDDM  
Kjos et al.,1993,1998  Fasting glucose>140mg/dL or 2-hour glucose >=200 mg/dL(after 75g OGTT)  National Diabetes Data Group,1979
Pettitt et al.,1997  2-hour glucose>=200mg/dL(after 75 g OGGTT)  World Health Organization,1994
Pettitt et al.,1998  2-hour glucose>=200mg/dL(after 75 g OGGTT)  World Health Organization,1985
Young et al.,2002  Fasting glucose>=126mg/dL  American Diabetes Association,1997
Expert Comm. 2003 Fasting glucose>=126mg/dL, on 2 occasions American Diabetes Association,2003
 

 

 Table 2: Differences in Diagnostic Criteria for Gestational Diabetes(GDM)

Authors Diagnostic Criteria Reference
 

>=2 of the following:

 
Kjos et al.,1993,1998 Fasting glucose>=105 mg/dL,1-hour>=190, 2-hour>=165,3-hour>=145(after 100g OGTT) National Diabetes Data Group,1979
Pettitt et al.,1998 2-hour glucose>=mg/dL(after 75g OGTT) World Health Organization,1985
 

>=2 of the following:

 
Cordero et al.,1999 Fasting glucose>=95 mg/dL,1-hour>=180, 2-hour>=155, 3 -hour >=140(after 100g OGTT) American College of Obstetricians and Gynecologists,1994
Knights et al.,1999 2-hour glucose>=144 mg/dL(after 75 g OGTT) Australasian Diabetes in Pregnancy Society
MacNeill et al.,2001 1-hour glucose>140 mg/dL(after 50g OGTT) and >=2 of the following : fasting glucose>=95 mg/dL,1-hour>=190,             2-hour>=165, 3-hour>=145(after 100 g OGTT) O'Sullivan,1984
Sebire et al. 2001

Criteria not specified

 
 

>= 2 of the following

 
Plagemann et al.,2002 Fasting glucose>100 mg/dL,1-hour>160,2-hour>130(after 50 g OGGTT) Fuhrmann,1998

OGTT=Oral glucose tolerance test

 

Author Conclusion:

Key teaching points:

  • Women with type 2 diabetes or gestational diabetes are less likely to breastfeed than women without diabetes.
  • Breastfeeding improves the subsequent glucose tolerance of mothers with diabetes.
  • Breastfeeding may reduce the risk of type 2 diabetes in children.
  • Current recommendations include 6 months of exclusive breastfeeding and continued breastfeeding for at least 12 months.
  • Women with a history of gestational diabetes should be screened with a fasting plasma glucose at 6 weeks postpartum and annually.

Limitations:

  • Definition of breast feeding - lack of detailed information on exclusivity, frequency or duration across the studies reviewed.
  • Definition of diabetes- (1) the definitions of diabetes varied among the outcomes including impaired glucose tolerance, type 2 diabetes, NIDDM, and gestational diabetes; (2) most researchers, not all, utilized either the American Diabetes Association or World Health Organization criteria; (3) oral glucose tolerance testing was a commonly used test, although there was considerable variation in the amount of the glucose load, the timing of the testing, and thresholds for diagnosis.

 

 

Funding Source:
Reviewer Comments:
Criteria for the systematic review and study limitations were well delineated.
Quality Criteria Checklist: Review Articles
Relevance Questions
  1. Will the answer if true, have a direct bearing on the health of patients? Yes
  2. Is the outcome or topic something that patients/clients/population groups would care about? Yes
  3. Is the problem addressed in the review one that is relevant to dietetics practice? Yes
  4. Will the information, if true, require a change in practice? Yes
 
Validity Questions
  1. Was the question for the review clearly focused and appropriate? Yes
  2. Was the search strategy used to locate relevant studies comprehensive? Were the databases searched and the search termsused described? Yes
  3. Were explicit methods used to select studies to include in the review? Were inclusion/exclusion criteria specified andappropriate? Wereselectionmethods unbiased? Yes
  4. Was there an appraisal of the quality and validity of studies included in the review? Were appraisal methodsspecified,appropriate, andreproducible? Yes
  5. Were specific treatments/interventions/exposures described? Were treatments similar enough to be combined? Yes
  6. Was the outcome of interest clearly indicated? Were other potential harms and benefits considered? Yes
  7. Were processes for data abstraction, synthesis, and analysis described? Were they applied consistently acrossstudies and groups? Was thereappropriate use of qualitative and/or quantitative synthesis? Was variation in findings among studies analyzed? Were heterogeneity issued considered? If data from studies were aggregated for meta-analysis, was the procedure described? Yes
  8. Are the results clearly presented in narrative and/or quantitative terms? If summary statistics are used, are levels ofsignificance and/or confidence intervals included? Yes
  9. Are conclusions supported by results with biases and limitations taken into consideration? Are limitations ofthe review identified anddiscussed? Yes
  10. Was bias due to the review's funding or sponsorship unlikely? Yes