DALI: Vitamin D and lifestyle intervention for gestational diabetes mellitus (GDM) prevention: an European multicentre, randomised trial – study protocol
1 Department of Public and Occupational Health, EMGO+−Institute for Health and Care Research, VU University Medical Centre, Van der Boechorststraat 7, 1081BT Amsterdam, the Netherlands
2 KU Leuven Department of Development and Regeneration: Pregnancy, Fetus and Neonate, Gynaecology and Obstetrics, University Hospitals Leuven, Leuven, Belgium
3 Department of Obstetrics and Gynecology, Medizinische Universitaet Graz, Graz, Austria
4 Institut de Recerca de l’Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
5 CIBER Bioengineering, Biomaterials and Nanotechnology, Instituto de Salud Carlos III, Madrid, Spain
6 Medical University of Vienna, Vienna City, Austria
7 Center for Pregnant Women with Diabetes, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
8 Odense University Hospital, Odense, Denmark
9 National University of Ireland, Galway, Ireland
10 Universita Degli Studi di Padova, Padua, Italy
11 Università di Pisa, Pisa, Italy
12 Uniwersytet Medyczny im Karola Marcinkowskiego W Poznaniu, Poznan, Poland
13 6 Recherche en Santé Lawson SA, Bronschhofen, Switzerland
14 BAP Health Outcomes Research SL, Oviedo, Spain
15 Department of Medical Psychology, EMGO+−Institute for Health and Care Research, VU University Medical Centre, Amsterdam, the Netherlands
16 Institute of Metabolic Science, Addenbrookes Hospital, Cambridge, England
BMC Pregnancy and Childbirth 2013, 13:142 doi:10.1186/1471-2393-13-142Published: 5 July 2013
Gestational diabetes mellitus (GDM) is an increasing problem world-wide. Lifestyle interventions and/or vitamin D supplementation might help prevent GDM in some women.
Pregnant women at risk of GDM (BMI≥29 (kg/m2)) from 9 European countries will be invited to participate and consent obtained before 19+6 weeks of gestation. After giving informed consent, women without GDM will be included (based on IADPSG criteria: fasting glucose<5.1mmol; 1 hour glucose <10.0 mmol; 2 hour glucose <8.5 mmol) and randomized to one of the 8 intervention arms using a 2×(2×2) factorial design: (1) healthy eating (HE), 2) physical activity (PA), 3) HE+PA, 4) control, 5) HE+PA+vitamin D, 6) HE+PA+placebo, 7) vitamin D alone, 8) placebo alone), pre-stratified for each site. In total, 880 women will be included with 110 women allocated to each arm. Between entry and 35 weeks of gestation, women allocated to a lifestyle intervention will receive 5 face-to-face, and 4 telephone coaching sessions, based on the principles of motivational interviewing. The lifestyle intervention includes a discussion about the risks of GDM, a weight gain target <5kg and either 7 healthy eating ‘messages’ and/or 5 physical activity ‘messages’ depending on randomization. Fidelity is monitored by the use of a personal digital assistance (PDA) system. Participants randomized to the vitamin D intervention receive either 1600 IU vitamin D or placebo for daily intake until delivery. Data is collected at baseline measurement, at 24–28 weeks, 35–37 weeks of gestation and after delivery. Primary outcome measures are gestational weight gain, fasting glucose and insulin sensitivity, with a range of obstetric secondary outcome measures including birth weight.
DALI is a unique Europe-wide randomised controlled trial, which will gain insight into preventive measures against the development of GDM in overweight and obese women.