Mediators of Lifestyle Behaviour Changes in Obese Pregnant Women. Secondary Analyses from the DALI Lifestyle Randomised Controlled Trial.

Mireille Nm van Poppel, Judith G M Jelsma, David Simmons, Roland Devlieger, Goele Jans, Sander Galjaard, Rosa Corcoy, Juan M. Adelantado, Fidelma Dunne, Jürgen Harreiter, Alexandra Kautzky-Willer, Peter Damm, Elisabeth R. Mathiesen, Dorte M. Jensen, Lise-Lotte Andersen, Mette Tanvig, Annunziata Lapolla, Maria-Grazia Dalfra, Allessandra Bertolotto, Ewa Wender-Ozegowska, Agnieszka Zawiejska, David Hill, Gernot Desoye, Frank J. Snoek

Journal: Nutrients 2019;11(2):311

PMID: 30717227

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Obesity in pregnancy is rising and is associated with increased risks for both mother and baby. In particular, obese women and women with excess weight gain during pregnancy are at an increased risk for developing gestational diabetes (GDM). A better understanding of what drives behaviour change in obese pregnant women is needed to improve the effectiveness of lifestyle interventions such as dietary changes. In this randomised controlled trial, researchers set out to assess what factors might support behaviour change in pregnant women at risk of GDM. A total of 436 women, with pre-pregnancy body mass index of ≥29 kg/m², without GDM, were split into four groups: three of them received counselling based on motivational interviewing (MI) on 1) healthy eating and physical activity, 2) healthy eating alone or 3) physical activity alone, whilst the fourth group received their usual care. Physical activity and food intake were measured at the start of the study, and at 24-28 and 35-37 weeks of pregnancy. Social and psychological factors such as outcome expectancy, risk perception, task self-efficacy (peoples’ confidence to succeed in a specific situation) and social support were measured at those same time points and considered as possible mediators of intervention effects on lifestyle. All three groups that received MI demonstrated an increased positive outcome expectancy for GDM reduction, perceived risk to the baby and increased task self-efficacy. Women with higher self-efficacy tended to be more physically active and consumed less sugary drinks and smaller portion sizes. The authors concluded that motivational interviewing was successful in increasing outcome expectancy and task self-efficacy, both of which were related to improvements in diet and physical activity.

Abstract

A better understanding of what drives behaviour change in obese pregnant overweight women is needed to improve the effectiveness of lifestyle interventions in this group at risk for gestational diabetes (GDM). Therefore, we assessed which factors mediated behaviour change in the Vitamin D and Lifestyle Intervention for GDM Prevention (DALI) Lifestyle Study. A total of 436 women, with pre-pregnancy body mass index ≥29 kg/m², ≤19 + 6 weeks of gestation and without GDM, were randomised for counselling based on motivational interviewing (MI) on healthy eating and physical activity, healthy eating alone, physical activity alone, or to a usual care group. Lifestyle was measured at baseline, and at 24⁻28 and 35⁻37 weeks of gestation. Outcome expectancy, risk perception, task self-efficacy and social support were measured at those same time points and considered as possible mediators of intervention effects on lifestyle. All three interventions resulted in increased positive outcome expectancy for GDM reduction, perceived risk to the baby and increased task self-efficacy. The latter mediated intervention effects on physical activity and reduced sugared drink consumption. In conclusion, our MI intervention was successful in increasing task self-efficacy, which was related to improved health behaviours.

Address: Institute of Sport Science, University of Graz, 8010 Graz, Austria. [email protected].; Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Public and Occupational Health, Amsterdam Public Health research institute, 1081 BT Amsterdam, The Netherlands. [email protected].; Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Public and Occupational Health, Amsterdam Public Health research institute, 1081 BT Amsterdam, The Netherlands. [email protected].; Western Sydney University, Campbelltown, Sydney, NSW 2760, Australia. [email protected].; KU Leuven Department of Development and Regeneration: Pregnancy, Fetus and Neonate, Gynaecology and Obstetrics, University Hospitals Leuven, 3000 Leuven, Belgium; KU Leuven Department of Development and Regeneration: Pregnancy, Fetus and Neonate, Gynaecology and Obstetrics, University Hospitals Leuven, 3000 Leuven, Belgium; Department of Obstetrics and Gynaecology, Division of Obstetrics and Prenatal Medicine, Erasmus MC, University Medical Centre Rotterdam, 3015 GD Rotterdam, The Netherlands; CIBER Bioengineering, Biomaterials and Nanomedicine, Instituto de Salud Carlos III, 50018 Zaragoza, Spain; Institut de Recerca de l’Hospital de la Santa Creu i Sant Pau, 08025 Barcelona, Spain; Galway Diabetes Research Centre (GDRC) and National University of Ireland, H91 CF50 Galway, Ireland; Gender Medicine Unit, Endocrinology and Metabolism, Dept. Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria; Center for Pregnant Women with Diabetes, Departments of Endocrinology and Obstetrics, Rigshospitalet and The Clinical Institute of Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1165 Copenhagen, Denmark; Steno Diabetes Center Odense, Odense University Hospital, 5000 Odense, Denmark; Department of Gynecology and Obstetrics, Odense University Hospital, 5000 Odense, Denmark; Department of Clinical Research, Faculty of Health Science, University of Southern Denmark, 5230 Odense, Denmark; Department of Gynecology and Obstetrics, Odense University Hospital, 5000 Odense, Denmark; Department of Clinical Research, Faculty of Health Science, University of Southern Denmark, 5230 Odense, Denmark; Department of Clinical Research, Faculty of Health Science, University of Southern Denmark, 5230 Odense, Denmark; Department of Medical and Surgical Sciences. Università degli Studi di Padova, 35100 Padua, Italy; Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy; Department of Reproduction, Poznan University of Medical Sciences, 61-701 Poznan, Poland; Recherche en Santé Lawson SA, 9952 St. Gallen, Switzerland; Department of Obstetrics and Gynecology, Medical University, 8036 Graz, Austria; Department of Medical Psychology, Amsterdam Public Health research institute, Amsterdam University Medical Centers, VU University, 1081 HZ Amsterdam, The Netherlands

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