title: A prediction model for superimposed preeclampsia in women with chronic hypertension during pregnancy.
abstract: OBJECTIVE
  Women with chronic hypertension are at increased risk for superimposed preeclampsia. We developed a prediction algorithm for superimposed preeclampsia using clinical and laboratory information that were measured early in pregnancy.
  
  
  METHODS
  A secondary analysis of data that were collected from 110 women with chronic hypertension who were enrolled in a trial of calcium supplementation was performed. Blood pressure, the renin-angiotensin system, and calcium metabolism were assessed at 12, 20, 28, and 36 weeks of gestation and 6 weeks after delivery. Multivariable logistic regression was used to develop the predictive model.
  
  
  RESULTS
  Thirty-seven women had superimposed preeclampsia. The final model included systolic blood pressure, serum uric acid, and plasma renin activity, which were all measured at 20 weeks of gestation. Women with high systolic blood pressure (>140 mm Hg), elevated uric acid (>3.6 mg/dL), and low plasma renin activity (<4 ng/mL/hr) had an 86% probability of having superimposed preeclampsia. Women with 2 risk factors had a 62% probability of superimposed preeclampsia, and women with only 1 risk factor had a 30% to 40% probability of superimposed preeclampsia.
  
  
  CONCLUSIONS
  We developed a prediction algorithm that can be validated in future studies for superimposed preeclampsia for women with chronic hypertension.
authors.affiliation: Division of Nephrology and Hypertension, Weill Medical College of Cornell University, New York, NY, USA.
authors.forename: Phyllis
authors.initials: P
authors.lastname: August
authors.forename: Geraldine
authors.initials: G
authors.lastname: Helseth
authors.forename: E Francis
authors.initials: EF
authors.lastname: Cook
authors.forename: Cristina
authors.initials: C
authors.lastname: Sison
mesh_terms: D000328:Adult; D001794:Blood Pressure; D005260:Female; D006801:Humans; D006973:Hypertension; D008962:Models, Theoretical; D011225:Pre-Eclampsia / Q000175:diagnosis* / Q000209:etiology; D011237:Predictive Value of Tests; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D012083:Renin / Q000097:blood; D012307:Risk Factors; D014527:Uric Acid / Q000097:blood
chemical_list: D014527:Uric Acid; D012083:Renin