Hypertensive disorders in pregnancy and preterm delivery and subsequent stroke in Asian women: a retrospective cohort study.

BACKGROUND AND PURPOSE: Few studies exist concerning the risk of stroke associated with hypertensive disorders in pregnancy (HDP) in Asian women. This study investigates whether preterm delivery further complicates this risk in women with HDP in Taiwan.

METHODS: Based on universal insurance claims data, 1092 pregnant women with newly diagnosed HDP from 2000 to 2004 and aged 15 to 40 years were identified as the HDP cohort. Then, 4715 randomly selected persons without HDP frequency matched with the index year were designated as the non-HDP controls. Both cohorts were followed-up until the end of 2008 to measure the incidence of stroke.

RESULTS: The HDP cohort had a higher incidence of stroke than the non-HDP cohort (30.1 vs 12.8 per 10 000 person-years), with an overall adjusted hazard ratio of 2.04 (95% CI, 1.18- 3.51) for stroke. Preterm delivery increased the risk of stroke to 3.22-fold (95% CI, 1.48-6.99; P for trend=0.002). The age-specific V-shape risk association showed that the highest risk of stroke was noted among subjects 15 to 18 years old in the HDP group (hazard ratio, 13.4; 95% CI, 1.54-116.7) and followed by women aged 35 years and older (hazard ratio, 5.56; 95% CI, 1.47-21.0).

CONCLUSIONS: Pregnant women with HDP have an increased risk of subsequent stroke. Preterm delivery and older ages increase the risk of subsequent stroke. Adolescents with HDP also have an elevated risk of stroke. Early identification of women with HDP is needed for prevention.