AUTOMATED, AMBULATORY, OR CONVENTIONAL BLOOD-PRESSURE MEASUREMENT IN PREGNANCY - WHICH IS THE BETTER PREDICTOR OF SEVERE HYPERTENSION

OBJECTIVES: Our purpose was to investigate the benefit, ii any, of aut omated blood pressure monitoring over obstetric day unit conventional blood pressure measurement in the assessment of hypertensive pregnanci es. STUDY DESIGN: A prospective, observational study was carried out i n two large teaching hospitals. Three hundred and forty-eight women wi th a confirmed clinic blood pressure of at least 140/90 mm Hg were rec ruited. Conventional blood pressure measurements (less than or equal t o 5) were obtained on the day unit and simultaneously an ambulatory bl ood pressure monitor was applied for 24 hours. The predictive ability of day unit assessment (blood pressure >140/90 mm Hg) and automated bl ood pressure monitoring (blood pressure >130/85 mm Hg) was compared. P rincipal outcome measures included the occurrence of severe hypertensi on (>160/110 mm Hg) and proteinuria (>500 mg or 2+) within (a) 2 weeks and (b) the remainder of the pregnancy. Thompson's method was used to compare sensitivity and specificity of the day unit blood pressure an d automated blood pressure monitoring. RESULTS: Three hundred and fort y-eight women were recruited to the study. The comparison between auto mated blood pressure monitoring and conventional blood pressure measur ement for both sensitivity and specificity for systolic and diastolic blood pressure revealed increased sensitivity and decreased specificit y with automated blood pressure monitoring for all principal outcomes except development of proteinuria for systolic blood pressure. Sensiti vity for the outcomes was increased with automated blood pressure moni toring by between 14% and 27% for systolic blood pressure and between 7% and 39% for diastolic blood pressure, with the greatest improvement seen for the development of severe hypertension within 2 weeks of ass essment. CONCLUSIONS: In the assessment of hypertensive pregnancies, a utomated blood pressure measurement was a significantly better predict or (compared with conventional day unit assessment) for the developmen t of severe hypertension within 2 weeks of assessment for both systoli c and diastolic blood pressure.