Non-proteinuric pre-eclampsia: a novel risk indicator in women with gestational hypertension

Objective To determine whether outcomes differed for women with pre-eclampsia according to the presence of proteinuria and whether non-proteinuric pre-eclampsia is similar to gestational hypertension. Design From 1987 to 2005, at three hospitals in Sydney, Australia, women referred to the obstetric medicine team were recruited. Outcomes for three groups were compared: proteinuric pre-eclampsia, non-proteinuric pre-eclampsia and gestational hypertension. Results Women with proteinuric pre-eclampsia were more likely to have severe hypertension ( 39 versus 30%, P = 0.003), deliver preterm infants ( 39 versus 30%, P = 0.007) and had a higher perinatal mortality rate (25.2 versus 5.7 per 1000, P= 0.02) than those with non-proteinuric pre-eclampsia, who were more likely to have thrombocytopenia and liver disease. Women with non-proteinuric pre-eclampsia were more likely to have multiple pregnancies (3.9 versus 9.9%, P < 0.001), experience severe hypertension (8.9 versus 29.7%, P < 0.001), and deliver preterm infants (11.3 versus 30.2%, P < 0.001) who were small for gestational age (12.7 versus 20.9%, P < 0.001) than those with gestational hypertension. Conclusion This study highlights differences between non-proteinuric pre-eclampsia and gestational hypertension. The subclassification of `non-proteinuric pre-eclampsia' should be added to existing classification systems to alert clinicians to potential risks.