title: Can adverse maternal and perinatal outcomes be predicted when blood pressure becomes elevated? Secondary analyses from the CHIPS (Control of Hypertension In Pregnancy Study) randomized controlled trial.
abstract: For women with chronic or gestational hypertension in CHIPS (Control of Hypertension In Pregnancy Study, NCT01192412), we aimed to examine whether clinical predictors collected at randomization could predict adverse outcomes.
  
  
  
  This was a planned, secondary analysis of data from the 987 women in the CHIPS Trial. Logistic regression was used to examine the impact of 19 candidate predictors on the probability of adverse perinatal (pregnancy loss or high level neonatal care for >48 h, or birthweight <10th percentile) or maternal outcomes (severe hypertension, preeclampsia, or delivery at <34 or <37 weeks). A model containing all candidate predictors was used to start the stepwise regression process based on goodness of fit as measured by the Akaike information criterion. For face validity, these variables were forced into the model: treatment group ("less tight" or "tight" control), antihypertensive type at randomization, and blood pressure within 1 week before randomization. Continuous variables were represented continuously or dichotomized based on the smaller p-value in univariate analyses. An area-under-the-receiver-operating-curve (AUC ROC) of ≥0.70 was taken to reflect a potentially useful model.
  
  
  
  Point estimates for AUC ROC were <0.70 for all but severe hypertension (0.70, 95% CI 0.67-0.74) and delivery at <34 weeks (0.71, 95% CI 0.66-0.75). Therefore, no model warranted further assessment of performance.
  
  
  
  CHIPS data suggest that when women with chronic hypertension develop an elevated blood pressure in pregnancy, or formerly normotensive women develop new gestational hypertension, maternal and current pregnancy clinical characteristics cannot predict adverse outcomes in the index pregnancy.
authors.affiliation: St. George's University of London, London, UK.|St. George's University Hospitals NHS Trust, London, UK.|Obstetrics and Gynaecology, University of British Columbia, Vancouver, British Columbia, Canada.|Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Laura A
authors.identifier: 0000-0002-1355-610X
authors.initials: LA
authors.lastname: Magee
authors.affiliation: St. George's University of London, London, UK.|St. George's University Hospitals NHS Trust, London, UK.|Obstetrics and Gynaecology, University of British Columbia, Vancouver, British Columbia, Canada.|Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Peter
authors.identifier: 0000-0003-4136-3070
authors.initials: P
authors.lastname: von Dadelszen
authors.affiliation: Obstetrics and Gynaecology, University of British Columbia, Vancouver, British Columbia, Canada.|School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Joel
authors.identifier: 0000-0003-4936-4086
authors.initials: J
authors.lastname: Singer
authors.affiliation: Centre for Health Evaluation and Outcome Sciences (CH_EOS), Providence Health Care Research Institute, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Terry
authors.identifier: 0000-0003-2582-2337
authors.initials: T
authors.lastname: Lee
authors.affiliation: Medicine and Obstetrics and Gynaecology, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Evelyne
authors.identifier: 0000-0003-2452-8486
authors.initials: E
authors.lastname: Rey
authors.affiliation: Obstetrics and Gynaecology, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Susan
authors.identifier: 0000-0002-0600-4833
authors.initials: S
authors.lastname: Ross
authors.affiliation: Pediatrics, University of Toronto, Toronto, Ontario, Canada.|Obstetrics and Gynaecology, University of Toronto, Toronto, Ontario, Canada.|The Centre for Mother, Infant and Child Research, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Elizabeth
authors.identifier: 0000-0002-9468-2860
authors.initials: E
authors.lastname: Asztalos
authors.affiliation: Obstetrics and Gynaecology, University of Toronto, Toronto, Ontario, Canada.|The Centre for Mother, Infant and Child Research, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Kellie E
authors.identifier: 0000-0002-7327-2600
authors.initials: KE
authors.lastname: Murphy
authors.affiliation: Obstetrics and Gynaecology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Jennifer
authors.identifier: 0000-0002-6308-9554
authors.initials: J
authors.lastname: Menzies
authors.affiliation: The Centre for Mother, Infant and Child Research, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Johanna
authors.identifier: 0000-0003-2295-3251
authors.initials: J
authors.lastname: Sanchez
authors.affiliation: Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Amiram
authors.identifier: 0000-0001-8279-8172
authors.initials: A
authors.lastname: Gafni
authors.affiliation: Obstetrics and Gynaecology, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Andrée
authors.identifier: 0000-0002-1723-7122
authors.initials: A
authors.lastname: Gruslin
authors.affiliation: Obstetrics and Gynaecology, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Michael
authors.identifier: 0000-0001-6792-4951
authors.initials: M
authors.lastname: Helewa
authors.affiliation: Obstetrics and Gynaecology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Eileen
authors.initials: E
authors.lastname: Hutton
authors.affiliation: Pediatrics, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Shoo K
authors.identifier: 0000-0002-2774-3301
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Medicine, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Alexander G
authors.identifier: 0000-0002-3419-5761
authors.initials: AG
authors.lastname: Logan
authors.affiliation: Obstetrics and Gynaecology, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Wessel
authors.identifier: 0000-0002-7243-2115
authors.initials: W
authors.lastname: Ganzevoort
authors.affiliation: Obstetrics and Gynaecology, Derriford Hospital, Plymouth, UK.
authors.forename: Ross
authors.identifier: 0000-0002-7890-3504
authors.initials: R
authors.lastname: Welch
authors.affiliation: Obstetrics and Gynaecology, University of Nottingham, Nottingham, UK.
authors.forename: Jim G
authors.identifier: 0000-0001-9764-6876
authors.initials: JG
authors.lastname: Thornton
authors.affiliation: Obstetrics and Gynaecology, Sherbrooke University, Sherbrooke, Quebec, Canada.
authors.forename: Jean Marie
authors.identifier: 0000-0002-1460-0889
authors.initials: JM
authors.lastname: Moutquin
mesh_terms: D000328:Adult; D019540:Area Under Curve; D001794:Blood Pressure; D001955:British Columbia; D005260:Female; D006801:Humans; D046110:Hypertension, Pregnancy-Induced / Q000175:diagnosis* / Q000517:prevention & control; D018579:Patient Selection; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D011296:Prenatal Diagnosis; D016032:Randomized Controlled Trials as Topic; D012044:Regression Analysis
keywords: Preexisting hypertension; adverse outcome; chronic hypertension; gestational hypertension; maternal; perinatal; prediction