Approximately 6% of pregnant women have high blood pressure (hypertension) in pregnancy. Hypertension during pregnancy can progress to pre-eclampsia, a severe onset of high blood pressure which can affect multiple organ systems and cause seizures. Changes in the management of pre-eclampsia, such as more aggressive treatment and protocols to restrict fluids administered into the veins, are considered to have improved important aspects of maternal and newborn health. However, their impact on the occurrence of a rare but serious adverse outcome such as acute renal failure (a rapid deterioration of kidney function) has not been adequately studied. Increases in acute renal failure have been reported, with a dramatic increase in Canada among women with hypertensive disorders of pregnancy. The aim of our study is to determine whether potential changes in pre-eclampsia management increased acute renal failure while improving other aspects of maternal and newborn health. We will analyze data from family doctor visits and hospital based medical records. Findings from this research will help health care providers and patients understand the risks and benefits of treating hypertension in pregnancy and to make the informed decisions about treatment options, potentially helping to improve the health of women and newborns.
The primary objective of this study is to determine whether obstetric acute renal failure rates rose in the United Kingdom following a series of confidential enquiries into maternal deaths reports recommending improvements in pre-eclampsia treatment. A secondary objective is to determine whether these recommendations achieved their objective of reducing the rates of pulmonary oedema and improving other maternal and infant health outcomes among women with pre-eclampsia and other hypertensive disorders of pregnancy. To achieve these objectives, we will conduct an interrupted time series study of pregnant women using retrospective data between April 1, 1998 and March 31, 2015. We hypothesize that following the confidential enquiry reports, pre-eclampsia treatment intensity increased, pulmonary oedema and other maternal and perinatal complications decreased among women with hypertensive disorders of pregnancy, and rates of acute renal failure increased.
The primary outcome will be the occurrence of acute renal failure, defined are occurring during the delivery episode or within 42 days of delivery within ICD-10 codes or Read codes. Secondary maternal outcomes will be assessed using a composite outcome of pulmonary oedema and other complications associated with hypertensive disorders of pregnancy including eclampsia, stroke, transient ischemic attack, retinal detachment, hepatic failure, hematoma or rupture, myocardial infarction, placental abruption or receipt of a blood transfusion, and intensity of anti-hypertensive treatment, as diagnosed in either the CPRD Gold or the HES in the delivery episode or 42 days postpartum. Secondary fetal or newborn outcomes (perinatal) will be assessed using a composite outcome of pregnancy loss (miscarriage, ectopic pregnancy, elective termination, stillbirth, neonatal death and overall perinatal death), transfer to intensive care unit, small for gestational age newborns, other perinatal outcomes of liveborn infants (bronchopulmonary dysplasia, Grade III or IV Intraventricular hemorrhage, cystic periventricular leukomalacia, stage 3 or 4 retinopathy of prematurity, necrotizing enterocolitis, hypoxic-ischemic encephalopathy, and sepsis.
Samy Suissa - Chief Investigator - Sir Mortimer B Davis Jewish General Hospital
Kristian Filion - Corresponding Applicant - McGill University
Anne-Marie Cote - Collaborator - University Of Sherbrooke
Azar Mehrabadi - Collaborator - Dalhousie University
Erin C. Strumpf - Collaborator - McGill University
Kate Bramham - Collaborator - King's College London (KCL)
KS Joseph (Joseph Kuruthukulangare) - Collaborator - University Of British Columbia
Laura A. Magee - Collaborator - St George's, University of London
Lisiane Leal - Collaborator - McGill University
pauline reynier - Collaborator - Sir Mortimer B Davis Jewish General Hospital
Qi Zhang - Collaborator - Sir Mortimer B Davis Jewish General Hospital
Robert Platt - Collaborator - McGill University
Azar Mehrabadi - Collaborator - McGill University
HES Admitted Patient Care;ONS Death Registration Data