Poster Presentation Australasian Diabetes in Pregnancy Society and Society of Obstetric Medicine Australia and New Zealand Joint Scientific Meeting 2021

Predictors for insulin use in gestational diabetes mellitus (#103)

Heather L Ford 1 2 , Isabella Champion 2 , Maya Reddy 1 2 , Ben W Mol 1 2 , Daniel L Rolnik 1 2 3
  1. Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
  2. Department of Obstetrics and Gynaecology, Monash Health, Melbourne, Victoria, Australia
  3. T.H. Chan School of Public Health, Harvard University, Cambridge, MA, USA

Background: Gestational diabetes mellitus (GDM) affects about 15% of pregnancies in Australia, with approximately 30% of those diagnosed with GDM requiring insulin therapy for the treatment of maternal hyperglycaemia1. There are severe well known risk factors for developing GDM, but there remain limited studies which show how these can be used to predict need for insulin treatment in women.

Aims: To investigate predictors of insulin therapy in women diagnosed with GDM from an oral glucose tolerance test (OGTT) performed during pregnancy.

Materials and Methods: This is a retrospective cohort study of 2048 singleton pregnancies complicated by GDM between 2016-2017 at a single, large health network in Melbourne, Australia. Data was obtained from hospital record and pathology result systems. Univariable and multivariable logistic regression models were fit to the data to obtain crude and adjusted odds ratios.

Results: In total, 31.6% of women required insulin therapy during pregnancy. Those requiring insulin had a higher fasting and 1-hour OGTT result, and were more likely to be diagnosed from their fasting result. Independent predictors of insulin use included maternal age, body mass index (BMI), being born in the South Asia region, previous pregnancy complicated by GDM, previous birthweight of greater than 90th percentile and results from the OGTT. Smoking status, conception by in vitro fertilisation, pre-existing hypertension and being of Aboriginal and Torres Strait Island background were not found to be predictors in our model. The final predictive model had a an area under the receiver-operating characteristics (ROC) curve of 0.7442 (95% CI 0.720 to 0.767) .

Conclusions: This study highlights the possible predictors of insulin use in those diagnosed with GDM, informing counselling for women who are newly diagnosed with gestational diabetes.

 

 

1 Australian Institute of Health and Welfare 2019. Incidence of gestational diabetes in Australia. Cat. No. CVD 85. Canberra: AIWH.