Ophthalmic artery peak systolic velocity ratio distinguishes pre-eclampsia from chronic and gestational hypertension: A prospective cohort study

Objective To examine whether the ophthalmic artery peak systolic velocity ratio (OA PSV-ratio) is higher in women with pre-eclampsia compared with gestational hypertension (GH) and chronic hypertension (CH), after controlling for confounding variables. Design Prospective cohort. Setting Specialist hypertension clinic in a tertiary referral centre. Population Singleton pregnancies presenting between 32(+0) and 36(+6) weeks of gestation with pre-eclampsia (n = 50), GH (n = 54) and CH (n = 56). Methods Paired measurements of maternal mean arterial pressure (MAP) and OA PSV-ratio were performed by trained sonographers. Multiple linear regression was fitted to the OA PSV-ratio, including maternal characteristics and medical history, GH, pre-eclampsia and MAP and use of antihypertensive medication. Main Outcome Measure Whether pre-eclampsia is independently associated with higher OA PSV-ratio. Results MAP was significantly higher in both GH (p = 0.0015) and pre-eclampsia (p = 0.008) than in CH pregnancies. There was no significant difference between pre-eclampsia and GH (0.670). The OA PSV-ratio was significantly higher in pre-eclampsia than CH (p = 0.0008) and GH (p = 0.015). There was no significant difference between the OA PSV-ratio in CH and GH (p = 0.352). Multiple linear regression modelling showed that the OA PSV-ratio was influenced by maternal weight (p = 0.005), maternal age (p = 0.014), antihypertensive medications (p = 0.007) and MAP (p < 0.0001). After controlling for these variables, the OA PSV-ratio was still significantly higher in those with pre-eclampsia (p = 0.0002). Conclusions The OA PSV-ratio is influenced by maternal weight, age, antihypertensive medications and MAP. Pre-eclampsia is an independent predictor of OA PSV-ratio, which therefore may be a useful point-of-care test when assessing women presenting with hypertension.