Microalbuminuria, Preeclampsia, and Preterm Delivery in Pregnant Women With Type 1 Diabetes: Results from a nationwide Danish study

OBJECTIVE: To study the association between microalbuminuria and development of preeclampsia and preterm delivery in pregnant women with type 1 diabetes. RESEARCH DESIGN AND METHODS: This was a population-based prospective study in 846 normoalbuminuric or microalbuminuric women with type 1 diabetes without antihypertensive treatment in early pregnancy. Data were collected prospectively by one to three caregivers in each center and reported to a central registry. RESULTS: The prevalence of microalbuminuria in the first trimester was 10%, median diabetes duration was 11 years, and third-trimester A1C was 6.6%. The frequencies of preeclampsia and preterm delivery before 34 weeks in the microalbuminuric group were 40 and 13%, both significantly higher than those in the normoalbuminuric group (12 and 6%, respectively, P < 0.001). After adjustments for possible confounders, significant predictors for development of preeclampsia were microalbuminuria (odds ratio 4.0 [95% CI]), nulliparity (3.1 [1.9–5.1]), and third-trimester A1C (1.3 [1.1–1.5] per 1% increase). Delivery before 34 weeks was associated with early microalbuminuria in univariate analyses, but in multivariate analyses A1C was the only significant predictor of this outcome. Preeclampsia was associated with a threefold higher risk of delivery before 34 weeks. CONCLUSIONS: The presence of microalbuminuria in early pregnancy is associated with a fourfold increased risk of developing preeclampsia. A1C values during pregnancy are highly predictive of both preeclampsia and preterm delivery. Future research with antihypertensive treatment in normotensive, microalbuminuric pregnant women to prevent preeclampsia is proposed.