This project focuses on evaluating a health promotion intervention among families where the mother has prior gestational diabetes mellitus (GDM) in the first year after delivery. The intervention focuses on the individual, family and health system levels. The aim is to increase quality of life and reduce the risk of type 2 diabetes among women with prior GDM and their families.

Face-it: A Health Promotion Intervention for Women with Prior Gestational Diabetes and their Families

AIM: The aim of the Face-it project is to increase quality of life and reduce the risk of type 2 diabetes (T2DM) among women with prior gestational diabetes mellitus (pGDM) and their families.

BACKGROUND: Women with pGDM are at high risk of developing type 2 diabetes. Partners and offspring of women with GDM are also at elevated risk of developing type 2 diabetes and related cardiometabolic conditions. Thus, not only are women with prior GDM at high risk of T2DM and related cardiometabolic conditions, their children and spouses are as well. Since the cumulative incidence of T2DM increases substantially within the first five years after delivery (Kim et al. 2002) there is a strong interest in identifying feasible and effective interventions in this time-period. Evidence from the state-of-the-art Diabetes Prevention Program suggests that intensive lifestyle intervention can reduce the risk of T2DM among women with pGDM (Ratner et al. 2008). However, sustainable changes in such behaviours are difficult and many women do not follow lifestyle recommendations after delivery (Stage et al. 2004). Given the highly elevated risk in this group, this is a substantial missed opportunity for health promotion aimed at prevention of T2DM for not only the mother, but the entire family. It is vital that efforts are based on a thorough understanding of the barriers to health promoting behaviours and involve carefully tailored solutions to overcome these barriers. The investigators hypothesise that a health promotion intervention that focuses on enhancing motivation, health literacy, action competences and social involvement in women with pGDM and their families will reduce diabetes risk and improve quality of life.

DESIGN: Face-it is a two-arm parallel-group randomised clinical trial with women as the unit of randomization comparing a health promotion intervention with a usual care control group.

PARTICIPANTS, RECRUITMENT AND ELIGIBILIGY: Women with pGDM will be recruited from obstetric departments at Aarhus University Hospital (AUH), Odense University Hospital (OUH) or Rigshospitalet (RH) around 24-40 weeks of pregnancy by a health care professional. To be eligible for enrolment into the study, women should also be able to provide written informed consent in Danish. Exclusion criteria is that the participants may not be participating in other postpartum intervention trials with a possible impact on the Face-it trial. Women with diabetes identified at baseline will be excluded. Partners of women and the new-born offspring are also invited to participate in the study. Informed consents are obtained from 1) woman and new-born offspring, including permission to obtain information from the medical record and blood samples for research biobank (woman only), 2) from partner, including blood samples for research biobank. A separate consent 3) is obtained for collection of blood for future biobank. In case of non-participation in the study, women are asked for consent to collect information from the medical record including health characteristics of woman and offspring related to pregnancy and birth.

SAMPLE SIZE AND RANDOMISATION: Based on prior studies, a mean difference in BMI after 1 year between the intervention and control groups for the women of -1.0 kg/m2 and standard deviation of 2.5 is expected. A sample size of 225 women will be required to detect such a difference in BMI when using a 2:1 randomisation procedure, a power of at least 80% and type 1 error of 5% (two-sided). The sample size increases to 460 women to allow for assuming 30% loss to follow-up between baseline and follow-up and another 30% will withdraw during the prolonged period from recruitment to baseline data collection and randomisation.

1/3 of participants will be randomised to the control group and 2/3 to the intervention group. The randomization procedure has been generated by an independent statistician and will be in blocks of 6/9/12/15 with a separate randomization at each of the three recruitment locations. Allocation will be concealed from both the participant and the investigators, who have the clinical and research responsibility, until baseline data have been collected, eligibility confirmed, and participation accepted. However, neither participants nor the investigators will be blinded to the participants intervention or control status after this point, but the status will be blinded for the analyst. A randomization list will be kept securely at the study site by an investigator with clinical responsibility. Both the intervention and usual care group will be part of the evaluation of the Face-it trial and therefore invited to baseline and follow-up clinical examinations. Participants will be informed by a research assistant about whether they have been allocated to the control or intervention group.

INTERVENTION: The intervention has been developed in a thorough and iterative co-creation process with health care providers and families, where the mothers has pGDM to ensure that it is carefully tailored to the needs and challenges of the target group and enhance its sustainability. The three major components of the intervention are: 1) Health visitors as the core healthcare providers, 2) digital health technology, and 3) a structured cross-sectoral communication system in the healthcare system.

CONTROL: Participants in the control group will receive usual care practice, including recommended glucose control measures 3 months and one year after birth. Participants will receive advice about a healthy lifestyle according to the national recommendations from the Danish Health and Medicines Authority . Participants in the control group will be invited to participate in the health examination at baseline and follow-up and thereby obtain information about own health when attending the two clinical examinations.

STUDY PROCEDURES AND DATA COLLECTION: There are two study visits planned for each participant (women with pGDM, her partner and baby). Visit 1 (baseline) will take place 10-14 weeks postpartum. Visit 2 (follow-up) will take place around 12 months after delivery. The measurements taken at the visits are dependent on whether the participant is a women with pGDM, partner or offspring.

• 75g oral glucose tolerance test (OGTT) with measurements of glucose and insulin at 0, 30 and 120 minutes (women with pGDM only)
• Blood samples including fasting glucose, insulin secretion and insulin sensitivity Index, hbA1c, plasma lipids/ triglycerides, total cholesterol, HDL, LDL (women with pGDM and partners)
• Physical measures. Investigations on women with pGDM and their partners will include BMI, height, weight, waist- and hip circumference, body fat, blood pressure.
• Physical measures on offspring will include height, weight, abdominal- and head circumference (at one-year follow-up).
• Questionnaire. Detailed information will be collected about socio-demographic and -economic details, dietary-, physical activity-, and sleep patterns; quality of life, stress, depression, self-perceived health, health literacy, motivation for behaviour change, social support, self-efficacy, risk perception and knowledge about diabetes risk in women with pGDM and their partners. Information about obstetric history and breastfeeding will also be collected from women with pGDM
• Objective measures of physical activity and sedentary patterns (subgroup)

Inclusion Criteria:

• Women with a GDM diagnosis according to current Danish guidelines (2h oral glucose tolerance test ≥9.0mmol/l)
• Women with a GDM diagnosis should also be attending and giving birth at the obstetric departments at either Aarhus University hospital, Odense University Hospital or Rigshospitalet
• Partner or infant of women with a GDM diagnosis
• Able to provide written informed consent in Danish

Exclusion Criteria:

• Concomitant participation in other postpartum intervention trial with a possible impact on the participation in the face it trial

Withdrawal Criteria:

• Participant's withdrawal of the informed consent
• Safety concerns, judged by the investigator
• Non-compliance with the protocol, judged by the investigator
• Woman with pGDM being diagnosed with type 1 or type 2 diabetes before or during the first examination (baseline data collection visit)