Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12614000273684
Ethics application status
Approved
Date submitted
4/03/2014
Date registered
14/03/2014
Date last updated
14/03/2014
Type of registration
Retrospectively registered

Titles & IDs
Public title
Normal range for haemoglobin A1c (HbA1c), fructosamine and fasting blood glucose in different trimester of pregnancy in non-diabetic Hong Kong pregnant population
Scientific title
To determine the trimester-specific reference intervals for haemoglobin A1c (HbA1c), fructosamine and fasting blood glucose in non-diabetic Hong Kong pregnant population
Secondary ID [1] 284193 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Gestational diabetes mellitus 291298 0
Condition category
Condition code
Metabolic and Endocrine 291648 291648 0 0
Diabetes
Reproductive Health and Childbirth 291691 291691 0 0
Normal pregnancy
Reproductive Health and Childbirth 291692 291692 0 0
Antenatal care

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
To determine the trimester-specific reference intervals for HbA1c, fructosamine and fasting glucose in non-diabetic pregnant women, serum samples will be collected once per trimester.
In order to minimize inconvenience to subjects, serum sample collection in first trimester will be done at the time of first trimester Down screening. Serum sample collection in second trimester will be done at the time of oral glucose tolerance test. Serum sample collection in third trimester will be done at 34 – 37 weeks gestation during antenatal visit, together with serum sample collection for other purpose if possible.
Intervention code [1] 288888 0
Not applicable
Comparator / control treatment
Those diagnosed with gestational diabetes mellitus in this study were compared with those without gestational diabetes mellitus
Control group
Active

Outcomes
Primary outcome [1] 291575 0
Reference interval for HbA1c by serum assay
Timepoint [1] 291575 0
In first, second and third trimester
Primary outcome [2] 291576 0
Reference interval for fructosamine by serum assay
Timepoint [2] 291576 0
In first, second and third trimester
Primary outcome [3] 291577 0
Reference interval for fasting glucose by serum assay
Timepoint [3] 291577 0
In first, second and third trimester
Secondary outcome [1] 307096 0
Prevalence of gestational diabetes mellitus using the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria
Timepoint [1] 307096 0
After all deliveries in the study subjects
Secondary outcome [2] 307097 0
Birth weight > 90th percentile in patients with gestational diabetes mellitus diagnosed using IADPSG criteria
Timepoint [2] 307097 0
At birth in all the study subjects
Secondary outcome [3] 307098 0
Primary Caesarean section delivery in patients with gestational diabetes mellitus diagnosed using IADPSG criteria
Timepoint [3] 307098 0
At delivery in all the study subjects
Secondary outcome [4] 307099 0
Pre-eclampsia in patients with gestational diabetes mellitus diagnosed using IADPSG criteria,
Pre-eclampsia defined as new onset hypertension and significant proteinuria after 20 weeks gestation
Hypertension defined as systolic blood pressure of over 140mmHg or diastolic pressure of over 90mmHg in 2 measurements at least 4 hours apart
Significant proteinuria defined as urine dipstick of >= 1+, urine protein: creatinine ratio > 30mg/mmol, or 24 hour urine total protein of 300mg/day
Retrospective review of hospital records will be performed
Timepoint [4] 307099 0
Retrospective review of hospital records will be performed for all study subjects to identify pre-eclampsia during antenatal, intrapartum and postnatal period
Secondary outcome [5] 307100 0
Preterm delivery (< 37 weeks gestation) in patients with gestational diabetes mellitus diagnosed using IADPSG criteria
Timepoint [5] 307100 0
At delivery in all the study subjects
Secondary outcome [6] 307101 0
Shoulder dystocia (when additional obstetric manoeuvres are required to deliver the fetus after the head has delivered and gentle traction has failed, as documented in the hospital record) in patients with gestational diabetes mellitus diagnosed using IADPSG criteria
Retrospective review of hospital records will be performed
Timepoint [6] 307101 0
At delivery in all the study subjects
Secondary outcome [7] 307102 0
Birth trauma (third and fourth degree tear) in patients with gestational diabetes mellitus diagnosed using IADPSG criteria
Retrospective review of hospital records will be performed
Timepoint [7] 307102 0
At delivery in all the study subjects

Eligibility
Key inclusion criteria
Non-diabetic pregnant women who attend the first trimester Down screening (at 11 to 13+6 weeks gestation) in Queen Elizabeth Hospital, Hong Kong
Patients who signed written informed consent in Chinese or English version
Minimum age
No limit
Maximum age
No limit
Sex
Females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Patient with pre-existing diabetes mellitus
Patient refusal
Inability of patient to give informed consent

Study design
Purpose
Natural history
Duration
Longitudinal
Selection
Convenience sample
Timing
Both
Statistical methods / analysis
For estimation a reference range, 200 samples are required(1). For the analysis of prevalence of gestational diabetes mellitus using IADPSG criteria, it is expected the prevalence will be about 33% (2). Assuming a confidence interval of 95% and precision of +/- 5%, the sample size required is 339 subjects (3). To account for possible default and missing data, sample size of 400 subjects is chosen.

Independent paired t-test and chi-squares will be used to analyze the parametric and non-parametric data respectively. Non-parametric method will be used to determine the reference intervals, which does not assume a Gaussian type distribution. The lower and upper reference limits were estimated at the 2.5th and the 97.5th percentiles respectively. SPSS version 17.0 will be used for statistical analysis.

Reference:
(1) Lott JA, Mitchell LC, Moeschberger ML et al. Estimation of reference ranges: how many subjects are needed? Clin Chem. 1992 May;38(5):648-50.
(2) Landon MB, Gabbe SG. Gestational diabetes mellitus. Obstet Gynecol. 2011 Dec;118(6):1379-93.
(3) Kish, L., 1965. Survey Sampling. John Wiley and Sons Inc., New York. ISBN: 047148900X.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
1/02/2014
Actual
15/02/2014
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
400
Accrual to date
Final
Recruitment outside Australia
Country [1] 5861 0
Hong Kong
State/province [1] 5861 0

Funding & Sponsors
Funding source category [1] 288822 0
Hospital
Name [1] 288822 0
Queen Elizabeth Hospital
Country [1] 288822 0
Hong Kong
Primary sponsor type
Individual
Name
Dr Lee Hui Ling Helena
Address
H10, Queen Elizabeth Hospital
30 Gascoigne Road, Kowloon, Hong Kong
Country
Hong Kong
Secondary sponsor category [1] 287517 0
Hospital
Name [1] 287517 0
Department of Obstetrics and Gynaecology,
Queen Elizabeth Hospital
Address [1] 287517 0
H10, Queen Elizabeth Hospital
30 Gascoigne Road, Kowloon, Hong Kong
Country [1] 287517 0
Hong Kong

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 290662 0
Research Ethics Committee (Kowloon Central / Kowloon East)
Ethics committee address [1] 290662 0
Room 808, Block S
Queen Elizabeth Hospital
30 Gascoigne Road
Kowloon
Ethics committee country [1] 290662 0
Hong Kong
Date submitted for ethics approval [1] 290662 0
11/06/2013
Approval date [1] 290662 0
25/09/2013
Ethics approval number [1] 290662 0
KC/KE-13-0138/ER-3

Summary
Brief summary
The increased risk of adverse pregnancy outcome is related to glycaemic control, which can be monitored by glycated haemoglobin (HbA1c). HbA1c can identify the average blood glucose concentration over the previous months prior to the measurement. The correlation between HbA1c levels and clinical outcomes depends on appropriately-defined reference intervals, which have not been defined in Hong Kong pregnant women. Fructosamine can also be useful in monitoring the effectiveness of therapy in diabetes, in a manner analogous to the HbA1c. It reflects the glycaemic control over the past 2 – 3 weeks. Therefore it can determine the effectiveness of gestational diabetes mellitus (GDM) treatment earlier compare with HbA1c, which may improve pregnancy outcome in patients with GDM. However, there is only limited experience in use of fructosamine in patients with GDM.

Therefore, there is a need to establish trimester-specific reference intervals of HbA1c, fructosamine and fasting blood glucose in non-diabetic pregnant women in the local population, which may be useful in guiding treatment for GDM and diabetes mellitus in pregnancy.
Trial website
Trial related presentations / publications
Public notes
The aim of the study is to establish the normal range for the studied population before applying the tests in management of gestational diabetes mellitus in pregnancy. Those found to have gestational diabetes mellitus will be analyzed for the secondary outcomes.

Contacts
Principal investigator
Name 46666 0
Dr Lee Hui Ling Helena
Address 46666 0
H10, Queen Elizabeth Hospital
30 Gascoigne Road,
Kowloon,
Hong Kong
Country 46666 0
Hong Kong
Phone 46666 0
+852-29582235
Fax 46666 0
Email 46666 0
[email protected]
Contact person for public queries
Name 46667 0
Dr Lee Hui Ling Helena
Address 46667 0
H10, Queen Elizabeth Hospital
30 Gascoigne Road,
Kowloon,
Hong Kong
Country 46667 0
Hong Kong
Phone 46667 0
+852-29582235
Fax 46667 0
Email 46667 0
[email protected]
Contact person for scientific queries
Name 46668 0
Dr Lee Hui Ling Helena
Address 46668 0
H10, Queen Elizabeth Hospital
30 Gascoigne Road,
Kowloon,
Hong Kong
Country 46668 0
Hong Kong
Phone 46668 0
+852-29582235
Fax 46668 0
Email 46668 0
[email protected]

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No Supporting Document Provided



Results publications and other study-related documents

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