Evidence

Evidence tables

This table is a summary of the analysis reported in a guideline (underpinned by a systematic review) that focuses on the above important clinical question.


Confidence in the evidence is very low or low where GRADE has been performed and the intervention may be more effective/beneficial than the comparison for key outcomes. However, this is uncertain and new evidence could change this in the future.


Population: Pregnant women with type 1, type 2, or gestational diabetes

Intervention: Lower blood glucose target

Comparison: Higher blood glucose target

OutcomeEffectiveness (BMJ rating)?Confidence in evidence (GRADE)?

Fasting blood glucose <5.3 mmol/L versus ≥5.3 mmol/L in women with gestational diabetes

Pre-eclampsia

Favours intervention

Very Low

Large for gestational age

Favours intervention

Very Low

1-2 hour post-prandial blood glucose ≤7.8 mmol/L versus >7.8 mmol/L in women with pre-gestational diabetes (white class diabetes B to RF [see classification section in the BMJ Best Practice Gestational Diabetes topic]) 

Macrosomia at 29-32 weeks’ gestation

Favours intervention

Very Low

2 hour post-prandial blood glucose <6.4 mmol/L versus ≥6.4mmol/L in women with gestational diabetes

Pre-eclampsia

Favours intervention

Very Low

Large for gestational age

Favours intervention

Very Low

Recommendations as stated in the source guideline

The guideline committee states that pregnant women with any form of diabetes should maintain their capillary plasma glucose levels below 5.3mmol/L (fasting), 7.8mmol/L (1 hour after meals), or 6.4mmol/L (2 hours after meals), if achievable without causing problematic hypoglycaemia.

This table is a summary of the analysis reported in a guideline (underpinned by a systematic review) that focuses on the above important clinical question.


Confidence in the evidence is very low or low where GRADE has been performed and there is a trade off between benefits and harms of the intervention.


Population: People with type 2 diabetes

Intervention: Self-monitoring blood glucose

Comparison: No self-monitoring blood glucose (including usual care and self-monitoring of urine glucose)

OutcomeEffectiveness (BMJ rating)?Confidence in evidence (GRADE)?

Haemoglobin A1c (HbA1c) (follow up: 24-52 weeks)

Favours intervention

Low

Fasting blood glucose (mmol/L) (follow up: 26-52 weeks)

Favours intervention

Low

Post-prandial blood glucose (mg/dL) at 26 weeks for adults with type 2 diabetes on diet, anti-diabetic, and/or insulin medicines (follow up: 6 months)

Favours intervention

Low

Any hypoglycaemia from 26-52 weeks (follow up: 6-12 months)

Favours comparison

Low

Severe hypoglycaemia from 26-52 weeks (follow up: 6-12 months)

No statistically significant difference

Low

Adverse events at 6 months for adults with type 2 diabetes on oral anti-diabetes medicines (follow up: 6 months) 

No statistically significant difference

Moderate

Recommendations as stated in the source guideline

The guideline development group states: do not routinely offer self-monitoring of blood glucose levels for adults with type 2 diabetes unless:

  • the person is on insulin or

  • there is evidence of hypoglycaemic episodes or

  • the person is on oral medication that may increase their risk of hypoglycaemia while driving or operating machinery or

  • the person is pregnant, or is planning to become pregnant.

Note

The guideline development group noted that self-monitoring of blood glucose provides the potential for tight glycaemic control which reduces the risk of diabetes-related complications. However, the impact on hypoglycaemic events is important in determining the safety and acceptability in patients.

Cochrane Clinical Answers

Use of this content is subject to our disclaimer