Exploring Relationships Between Sleep, Physical Activity, Diet And Glycaemic Control During And After Gestational Diabetes: Studies With Activity Monitors

Abstract

Gestational diabetes (GDM) is a common pregnancy complication. It is associated with an increased risk of type 2 diabetes mellitus (T2DM) in the mother. Emerging evidence supports sleep as an additional modifiable risk factor of not only T2DM and glycaemic control but influences diet and exercise which are the mainstays of lifestyle intervention for GDM and T2DM prevention. Technologies such as activity monitors that can track physical activity and sleep can function as research tools with their objectivity and convenient but can also be integrated into lifestyle programs through their accessibility and interactivity.

In substudies of Smart Mums with Smart Phones 2 (SMs2), a randomised controlled trial of a postpartum lifestyle intervention using text messages and an activity monitor in women with GDM, this thesis explores the effect of sleep and exercise on glycaemic control in women with GDM during pregnancy; the relationship of sleep on exercise and weight in postpartum women with GDM and investigates the impact of COVID lockdown on physical activity of postpartum women.

Key findings include a trend towards improved postprandial blood glucose levels with increased steps during pregnancy; achieving healthy sleep targets during pregnancy improved the likelihood of reaching glycaemic targets; increased sleep duration after pregnancy was associated with more steps being taken; positive relationship between sleep and postpartum weight; postpartum physical activity paradoxically increased during COVID lockdown.

This thesis provides further evidence of a relationship between sleep, glycaemic control and diabetes risk. Sleep is an under-recognised risk factor that should be considered during GDM and post-partum. Activity monitors may optimise lifestyle interventions and support research data collection.