Gestational diabetes and progression to type two diabetes mellitus: missed opportunities of follow up and prevention?

Abstract

Background: The incidence of type 2 diabetes (T2DM) is increasing. Having a pregnancy complicated by gestational diabetes mellitus (GDM) is a potent risk factor for the later development of T2DM. Aims: To explore the characteristics of women diagnosed with GDM in a single centre and their follow up for progression to T2DM. Methods: A retrospective cohort study using anonymised data of one hundred and fifty four (154) women with GDM receiving maternity care at the Oxford University Hospitals NHS Foundation Trust (OUHFT) in 2010 and their follow up until 2018. Results: The prevalence of GDM in women delivering in Oxfordshire in 2010 was 3.4%. 70% of pregnant women were overweight or obese (with 51% being obese) at booking. Gestational weight gain (GWG) was excessive in 29% of women, when compared to Institute of Medicine (IOM) guidelines. Almost a quarter of women (23.4%) had no follow up after delivery. Over a median follow up of 3.5 years (range 0-8 years) nearly one in six (16.9%) of the total cohort (22% of those tested) went on to develop T2DM. 74% of women with GDM were multiparous, and 65% of nulliparous women were tested compared to 81% of multiparous women. There was a significant difference between multiparous women (53.8%) compared to nulliparous women (46.2%) developing T2DM (p=0.01). There was no significant difference in BMI (p=0.866) or GWG (p=0.83) in women who progressed to T2DM versus those who did not. Conclusion: The risk of T2DM after GDM is substantial however, follow up rates of this population is poor. Subsequent screening of women with GDM and their management crosses secondary and primary care with scope for improvement in counselling of women of the importance of annual reviews, in data collection and follow up in both obstetrics and general practice. The implementation of a recall system, an education programme for general practitioners and/or a registry of women diagnosed with GDM could be useful to identify those at high risk of developing T2DM as well as providing a platform for the potential development of interventions to prevent progression to T2DM after GDM.