Clinical Trial: Diagnostic Approaches in Gestational Diabetes and Impact of Ethnicity

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: Screening and Diagnostic Approaches in Gestational Diabetes (GDM) and the Impact of Ethnicity on Markers of Glycaemia in Pregnancy

Brief Summary:

Gestational diabetes (GDM) means raised blood glucose found for the first time in pregnancy. GDM is common, particularly in women from minority ethnicities. GDM does not cause any symptoms in the mother. GDM is associated with adverse pregnancy outcomes which can be improved with treatment of GDM. The United Kingdom National Institute for Health and Care Excellence (NICE) recommend pregnant women with one or more risk factors should have a 75g oral glucose tolerance test (OGTT). The OGTT is performed in a clinic with venous plasma glucose measured fasting and at 2 hours. This is resource-intensive, and some women with GDM may be missed by this risk-factor based approach. The International Association of Diabetes and Pregnancy Study Groups (IADPSG 2010) recommends screening all pregnant women with 2-hour, 3 sample (fasting, 1 and 2 hour), 75g OGTT, which is even more resource intensive. Developing more cost-effective and convenient approaches to screening for GDM is a priority.

The researchers will validate a new home-use OGTT system (hOGTT), which measures whole blood glucose in capillary blood ('finger-stick' sample), against the gold standard venous plasma glucose in pregnancy.

The researchers will also investigate the performance of glycated haemoglobin (HbA1c) in screening for GDM. HbA1c is used for diagnosis of diabetes outside of pregnancy, but is currently not recommended for screening for GDM.

The researchers will also investigate relationships between glucose measured in different samples (venous versus capillary), different fractions (plasma versus whole blood), and using different methods in pregnancy.

In a substudy the researchers will investigate: ethnic differences in HbA1c and other glycaemic markers; the cont

Detailed Summary:
Sponsor: King's College Hospital NHS Trust

Current Primary Outcome: Percentage of hOGTT venous plasma equivalent glucose (hOGTT-VPEqG) results within ±10% of paired venous plasma glucose measured on a YSI analyser (VPG-YSI) (reference standard). [ Time Frame: Each participant is studied on one occasion between 16-34 weeks gestation. ]

hOGTT-VPEqG (in mmol/l) is capillary whole blood glucose measured on the home Oral Glucose Tolerance Test (hOGTT) system (the device being evaluated) expressed as venous plasma equivalent glucose (VPEqG).

VPG-YSI (in mmol/l) is venous plasma glucose measured on YSI 2300 Stat Analyser (YSI Life Sciences), a recognised reference standard, average of 2 measurements.

Paired means samples taken at the same time.

Results will be reported for glucose (VPG-YSI) range 4.5-11mmol/L. This was chosen because it encompasses the GDM diagnostic cut-offs for both National Institute for Health and Care Excellence (NICE) 2015 and International Association of Diabetes and Pregnancy Study Groups (IADPSG) 2010 criteria.

Samples taken fasting and at 1 hour and 2 hours post 75g oral glucose load will be considered together in this analysis.



Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Percentage of hOGTT venous plasma equivalent glucose (hOGTT-VPEqG) results within ±15% of paired venous plasma glucose measured on a YSI analyser (VPG-YSI) (reference standard). [ Time Frame: Each participant is studied on one occasion between 16-34 weeks gestation. ]

    hOGTT-VPEqG (in mmol/l) is capillary whole blood glucose measured on the home Oral Glucose Tolerance Test (hOGTT) system (the device being evaluated) expressed as venous plasma equivalent glucose (VPEqG).

    VPG-YSI (in mmol/l) is venous plasma glucose measured on YSI 2300 Stat Analyser (YSI Life Sciences), a recognised reference standard, average of 2 measurements.

    Paired means samples taken at the same time.

    Results will be reported for glucose (VPG-YSI) range 4.5-11mmol/L. This was chosen because it encompasses the GDM diagnostic cut-offs for both National Institute for Health and Care Excellence (NICE) 2015 and International Association of Diabetes and Pregnancy Study Groups (IADPSG) 2010 criteria.

    Samples taken fasting and at 1 hour and 2 hours post 75g oral glucose load will be considered together in this analysis.

  • Percentage of hOGTT venous plasma equivalent glucose (hOGTT-VPEqG) results within ±20% of paired venous plasma glucose measured on a YSI analyser (VPG-YSI) (reference standard). [ Time Frame: Each participant is studied on one occasion between 16-34 weeks gestation. ]

    hOGTT-VPEqG (in mmol/l) is capillary whole blood glucose measured on the home Oral Glucose Tolerance Test (hOGTT) system (the device being evaluated) expressed as venous plasma equivalent glucose (VPEqG).

    VPG-YSI (in mmol/l) is venous plasma glucose measured on YSI 2300 Stat Analyser (YSI Life Sciences), a recognised reference standard, average of 2 measurements.

    Paired means samples taken at the same time.

    Results will be reported for glucose (VPG-YSI) range 4.5-11mmol/L. This was chosen because it encompasses the GDM diagnostic cut-offs for both National Institute for Health and Care Excellence (NICE) 2015 and International Association of Diabetes and Pregnancy Study Groups (IADPSG) 2010 criteria.

    Samples taken fasting and at 1 hour and 2 hours post 75g oral glucose load will be considered together in this analysis.

  • Sensitivity of the hOGTT system for diagnosis of GDM using NICE 2015 criteria (gold standard VPG-YSI). [ Time Frame: Each participant is studied on one occasion between 16-34 weeks gestation. ]

    VPG-YSI is venous plasma glucose measured on YSI 2300 Stat Analyser (YSI Life Sciences), a recognised reference standard, average of 2 measurements.

    NICE (National Institute for Health and Care Excellence) 2015 diagnostic criteria for GDM are: fasting venous plasma glucose ≥ 5.6mmol/L, 2-hour post 75g oral glucose venous plasma glucose ≥ 7.8mmol/L.

  • Specificity of the hOGTT system for diagnosis of GDM using NICE 2015 criteria (gold standard VPG-YSI). [ Time Frame: Each participant is studied on one occasion between 16-34 weeks gestation. ]

    VPG-YSI is venous plasma glucose measured on YSI 2300 Stat Analyser (YSI Life Sciences), a recognised reference standard, average of 2 measurements.

    NICE (National Institute for Health and Care Excellence) 2015 diagnostic criteria for GDM are: fasting venous plasma glucose ≥ 5.6mmol/L, 2-hour post 75g oral glucose venous plasma glucose ≥ 7.8mmol/L.

  • Sensitivity of the hOGTT system for diagnosis of GDM using IADPSG 2010 criteria (gold standard VPG-YSI). [ Time Frame: Each participant is studied on one occasion between 16-34 weeks gestation. ]

    VPG-YSI is venous plasma glucose measured on YSI 2300 Stat Analyser (YSI Life Sciences), a recognised reference standard, average of 2 measurements.

    IADPSG (the International Association of Diabetes and Pregnancy Study Groups) 2010 diagnostic criteria for GDM are: 1 or more of fasting venous plasma glucose ≥ 5.1mmol/L, 1-hour post 75g oral glucose venous plasma glucose ≥ 10.0mmol/L or 2-hour post 75g oral glucose venous plasma glucose ≥ 8.5mmol/L.

  • Specificity of the hOGTT system for diagnosis of GDM using IADPSG 2010 criteria (gold standard VPG-YSI). [ Time Frame: Each participant is studied on one occasion between 16-34 weeks gestation. ]

    VPG-YSI is venous plasma glucose measured on YSI 2300 Stat Analyser (YSI Life Sciences), a recognised reference standard, average of 2 measurements.

    IADPSG (the International Association of Diabetes and Pregnancy Study Groups) 2010 diagnostic criteria for GDM ar

    Original Secondary Outcome: Same as current

    Information By: King's College Hospital NHS Trust

    Dates:
    Date Received: July 11, 2016
    Date Started: March 2016
    Date Completion:
    Last Updated: April 12, 2017
    Last Verified: March 2016