Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12621001618842
Ethics application status
Approved
Date submitted
9/10/2021
Date registered
26/11/2021
Date last updated
8/11/2022
Date data sharing statement initially provided
26/11/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
Investigating Type 2 Diabetes after Gestational Diabetes: the DIVINE-NSW study.
Scientific title
Investigating Type 2 Diabetes after Gestational Diabetes in Women: the DIVINE-NSW study.
Secondary ID [1] 305500 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Gestational diabetes 323891 0
Condition category
Condition code
Metabolic and Endocrine 321406 321406 0 0
Diabetes
Reproductive Health and Childbirth 321639 321639 0 0
Fetal medicine and complications of pregnancy

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Eligible and consented participants will complete an online questionnaire (30 minutes) at a time and place convenient to them. Those that have not undergone an Oral Glucose Tolerance Test (OGTT) within the previous 12 months as recommended by NSW Health will be referred for an OGTT.

Additionally, study personnel will access details relating to the participant's prior GDM-affected pregnancy, GDM treatment and any subsequent pregnancies from the hospital maternity databases (Obstetrics/eMaternity at the Royal Hospital for Women and St George Hospital, and Cerner Maternity at Liverpool Hospital), and relevant clinics associated with the hospital.

A subset of participants will be invited to participate in a semi-structured virtual (phone or online) interview to understand their perspectives of GDM, long-term risks and willingness to take preventive medications (including willingness to participate in trials of preventive medicines). Interviews with healthcare providers will also be conducted to understand their views of long-term diabetes risk, screening, and preventive strategies for women with GDM.

Maximum variation sampling will be used to identify study participants for inclusion in the in-depth interviews. To identify patients, we have identified key dimensions of variation (age, severity of GDM, perception of risk of developing T2DM, highest level of education, socioeconomic status and cultural and language background). We will use these dimensions of variation to find cases that vary from each other as much as possible.

This approach will give us high-quality, detailed descriptions of women's perspectives and experiences from a unique set of backgrounds. It will also enable us to document important shared patterns that cut across cases. The same sampling technique will be used to identify healthcare providers. Gender and number of years post-specialisation will be used as criteria to achieve a representative sample of this group. The healthcare providers will not necessarily have any relationship with any participants.
Intervention code [1] 321903 0
Early Detection / Screening
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 329177 0
Prevalence of dysglycemia among women with recent GDM using their OGTT results and data-linkage to medical records.
Timepoint [1] 329177 0
at time of enrolment
Primary outcome [2] 329179 0
Predictors of dysglycemia among women with recent GDM using their OGTT results and data-linkage to medical records.
Timepoint [2] 329179 0
at time of enrolment
Primary outcome [3] 329407 0
Identify women's views and views of their healthcare providers on long-term risks of T2DM and barriers and facilitators to engage in screening and preventive strategies to mitigate these risks through in-depth interviews and a questionnaire.
This questionnaire was designed specifically for the study
Timepoint [3] 329407 0
at time of enrolment
Secondary outcome [1] 401718 0
Feasibility of a randomised controlled trial of preventive drug therapies in this population using a questionnaire.
This questionnaire was designed specifically for the study
Timepoint [1] 401718 0
at time of enrolment

Eligibility
Key inclusion criteria
- Aged 16 years or older and gave birth following GDM-affected pregnancy at one of the study hospitals January 1st 2017-June 30th 2021.
- Able to provide written informed consent.
- Fluent in one of the following languages: English, Arabic, Mandarin, Vietnamese, Bangla and Hindi.

Healthcare providers (obstetricians, endocrinologists, GPs)
- An obstetrician or endocrinologist employed by one of the three participating hospitals (at least one participant from each of St George Hospital, Royal Hospital for Women and Liverpool Hospital); AND
- A general practitioner belonging to each local GP network (identified through shared care participating hospitals)
- Experience in managing patients with gestational diabetes mellitus (GDM)
Minimum age
16 Years
Maximum age
No limit
Sex
Females
Can healthy volunteers participate?
No
Key exclusion criteria
- Diagnosed with diabetes prior to pregnancy
- Known inability to give informed consent to participate due to severe active mental health issues or major developmental disability.

Study design
Purpose
Screening
Duration
Cross-sectional
Selection
Defined population
Timing
Both
Statistical methods / analysis
Based on existing data from participating hospitals, we expect ~4500 eligible women. With a highly conservative estimate of 20% providing consent (our prior BP2 trial of follow-up after hypertensive pregnancy, which involves substantially higher participant commitment, has approximately 24% of eligible participants consenting), a sample size of ~1000 would provide precise overall estimates of postpartum dysglycemia prevalence. Assuming 60% of participants had a postpartum OGTT within six months of delivery and 10% of these have pre-diabetes, we would expect 80% power (2a=0.05) to detect a relative risk of 1.78 for T2DM development among those with pre-diabetes compared to those with normoglycaemia. This assumes 20% of those with pre-diabetes will have developed T2DM at a median of 18 months follow-up, which is more conservative than observed in LIVING.

Approximately 50 participants across the sites and 10-15 healthcare providers from each hospital and its local GP network will be recruited for the in-depth interviews. The qualitative interviews will continue with thematic analysis of all data contemporaneously against data collection until saturation is achieved. The coding framework development will be informed by Michie's Behaviour Change Theory (Michie's Theory). Based on LIVING, we anticipate the proposed sample size will achieve thematic saturation, however this can be increased if required.

Descriptive statistics will be used to report study characteristics, and multivariable modelling used to predict postpartum dysglycemia. Online questionnaire data will be analysed and reported using descriptive statistics (number and percentage) for closed answer questions and compared using Chi-squared testing. The open-ended questions will be analysed and reported thematically.

Michie's theory was used to guide the design of our qualitative tools. The theory consolidates key behaviour change frameworks and incorporates a Capability Opportunity Motivation-Behaviour (COM-B) Model. It will provide the ideal framework for generating evidence about the potential acceptability and uptake of pharmacological therapy, and where relevant, its interaction with lifestyle strategies.

This approach will enable us to investigate, from the perspectives of patients and their healthcare providers, women's motivations (including unconscious and conscious thoughts and goals) that influence behaviour, for example, engagement with lifestyle strategies and the uptake and adherence to medications. It will also investigate social and physical opportunities available to women to perform these behaviours as well as physical and psychological capability (including knowledge, skills and tools).

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
3/01/2022
Actual
4/07/2022
Date of last participant enrolment
Anticipated
27/01/2023
Actual
Date of last data collection
Anticipated
28/04/2023
Actual
Sample size
Target
1015
Accrual to date
170
Final
Recruitment in Australia
Recruitment state(s)
NSW
Recruitment hospital [1] 20704 0
Liverpool Hospital - Liverpool
Recruitment hospital [2] 20705 0
St George Hospital - Kogarah
Recruitment hospital [3] 20706 0
Royal Hospital for Women - Randwick
Recruitment postcode(s) [1] 35506 0
2170 - Liverpool
Recruitment postcode(s) [2] 35507 0
2217 - Kogarah
Recruitment postcode(s) [3] 35508 0
2031 - Randwick

Funding & Sponsors
Funding source category [1] 309858 0
University
Name [1] 309858 0
University of New South Wales
Country [1] 309858 0
Australia
Primary sponsor type
University
Name
University of New South Wales
Address
University of New South Wales
Sydney NSW 2052 Australia
Country
Australia
Secondary sponsor category [1] 310896 0
None
Name [1] 310896 0
Nil
Address [1] 310896 0
Nil
Country [1] 310896 0
Other collaborator category [1] 282017 0
Other Collaborative groups
Name [1] 282017 0
The George Institute for Global Health
Address [1] 282017 0
Level 5/1 King St, Newtown NSW 2042
Country [1] 282017 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 309597 0
South Eastern Sydney Local Health District Human Research Ethics Committee
Ethics committee address [1] 309597 0
District Executive Unit
Locked Mail Bag 21
Taren Point NSW 2229
Ethics committee country [1] 309597 0
Australia
Date submitted for ethics approval [1] 309597 0
01/10/2021
Approval date [1] 309597 0
21/03/2022
Ethics approval number [1] 309597 0
2022/PID00319

Summary
Brief summary
This project lays the foundations for an Australian trial to test the usefulness and safety of drug therapies to prevent the development of long-term diabetes among women who develop diabetes in pregnancy, gestational diabetes mellitus (GDM). GDM, previously considered a transient condition, is now an established risk factor for long-term diabetes. Women whose blood sugar levels do not return to normal soon after giving birth are at particularly high risk of developing established diabetes and consequent heart and blood vessel disease. Lifestyle interventions may help, but they are hard for busy mothers to adopt and sustain. Even with lifestyle interventions, these women still have substantial “residual risk”, warranting investigation of preventive drug therapies. Currently, clinical guidelines do not recommend routine use of medications because of the lack of adequate research. Our proposed research will provide critical information that will form the basis of a substantial Australian contribution to global research efforts in diabetes.

Our research will:
- Identify all women who were diagnosed with GDM from three (3) Sydney hospitals in the past 3 years and invite them to complete an online questionnaire and, if long-term diabetes has not already developed, to undergo a blood test to evaluate their glucose status.
- Invite a sample of women to participate in interviews to understand their perspectives of GDM, long-term risks and willingness to take preventive medications (including willingness to participate in trials of preventive medicines).
- Conduct interviews with healthcare providers to understand their views of long-term diabetes risk, screening and preventive strategies for women with GDM.

Collectively, this study will provide a contemporary snapshot of post-GDM care and outcomes from a diverse Australian population who receive obstetric care at large urban hospitals. These data will critically inform the design and conduct of a large-scale trial of preventive medications in this and similar populations.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 114714 0
A/Prof Amanda Henry
Address 114714 0
UNSW Medicine, University of New South Wales, Sydney, NSW 2052
Country 114714 0
Australia
Phone 114714 0
+61 2 9113 2315
Fax 114714 0
Email 114714 0
[email protected]
Contact person for public queries
Name 114715 0
Dr Vivian Lee
Address 114715 0
The George Institute for Global Health,
Level 5, 1 King St, Newtown NSW 2042
Country 114715 0
Australia
Phone 114715 0
+61280524823
Fax 114715 0
Email 114715 0
[email protected]
Contact person for scientific queries
Name 114716 0
Dr Vivian Lee
Address 114716 0
The George Institute for Global Health,
Level 5, 1 King St, Newtown NSW 2042
Country 114716 0
Australia
Phone 114716 0
+61 2 8052 4823
Fax 114716 0
Email 114716 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.