PP157. Risk of preeclampsia in pregnant women with gestational diabetes in Alberta.

INTRODUCTION: Gestational diabetes mellitus (GDM) may increase a woman's risk of developing preeclampsia (PET), a hypertensive (HTN) disorder of pregnancy associated with increased maternal and fetal morbidity and mortality [1-4]. The reported magnitude of the association between GDM and PET varies from no association to triple the risk [1-4]. OBJECTIVES: The objectives of this study were: first, to determine the association between GDM and PET; and second, to assess other factors that influence PET in a large cohort of pregnant women in Alberta. METHODS: A retrospective population-based cohort study was performed using the Alberta Perinatal Health Program (APHP) database. The APHP is a provincial clinical registry focused on the health of infants and their mothers. Women between the ages of 14 and 54 without preexisting diabetes (DM) who delivered between 2000 and 2009, were included in the primary analysis. Women with preexisting DM were included in the secondary analyses. Logistic regression was used to examine the association between GDM and PET after adjusting for baseline characteristics. RESULTS: A total of 430,012 women were included. The mean age was 28.5 years old (SD 5.6) and 42.9% were nulliparous. GDM was reported in 3.7% of women. Overall, 1.3% had PET, which was significantly higher in the GDM group (2.7% vs 1.3%; P<0.01). The unadjusted odds ratio (OR) (with 95% CI) for GDM as a risk factor for PET was 2.1 (1.9, 2.4). After adjustment for potential confounders, the OR remained significant at 1.9 (1.7, 2.1). Other significant risk factors for PET were: weight>91kg (2.6; 2.4, 2.7), nulliparity (3.3; 3.1, 3.5), preexisting HTN (5.6; 4.9, 6.4), and chronic kidney disease (5.8; 4.1, 8.2). When GDM was compared with preexisting DM, the risk of PET with GDM of 1.9 (1.4, 2.1) was in between that associated with DM on diet (1.4; 1.0, 2.9) and DM on insulin (3.3; 2.7, 3.9). CONCLUSION: Women with GDM in Alberta have a significantly higher risk of developing PET. Assessment of glycemic status in pregnancy may provide clinicians with a simple tool to assess risk that may guide PET surveillance.