By Jane Lewis
Several factors that increase the risk of pregnancy-associated stroke in women with pre-eclampsia have been highlighted in new research published in Stroke.
While it is known that pre-eclampsia affects up to 8% of pregnancies and increases stroke risk, it has not been clear which women with pre-eclampsia are at highest risk of pregnancy-associated stroke. In this large, new study, women with pre-eclampsia and stroke were found to be significantly more likely than controls to have severe pre-eclampsia or eclampsia (odds ratio [OR], 7.2), infections (OR, 3.0; predominantly genitourinary), prothrombotic states (OR, 3.5), coagulopathies (OR, 3.1) or chronic hypertension (OR, 3.2). Women with these conditions should be monitored more closely, while studies are required to document what reduces stroke risk, the study authors suggested.
The case–control study used billing data to identify 88,857 women (aged 12 to 55 years) admitted to New York state hospitals from 2003 to 2012 with pre-eclampsia or eclampsia, with or without ischaemic or haemorrhagic stroke, transient ischaemic attack or cerebral venous thrombosis. Of these women, 197 (0.2%) had pregnancy-associated and two-thirds were diagnosed in the first six weeks postpartum. The cumulative incidence of stroke in women with pre-eclampsia during the study was 222/100,000 – more than six times the stroke incidence of the overall pregnant population, the authors highlighted.
‘GPs have a great opportunity to detect pre-eclampsia and eclampsia, which are major drivers of maternal and fetal morbidity and mortality, and refer patients for specialist assistance,’ commented Associate Professor Anne Abbott, a neurologist at The Alfred Hospital and Knox Private Hospital in Melbourne. ‘This is particularly relevant given that the postpartum period is a high- risk time and the relatively early postpartum discharges in contemporary obstetric practice.’
According to Associate Professor Abbott, definitions used by clinicians involved in the study were likely those set by the American College of Obstetricians and Gynecologists in 2002 – i.e. pre-eclampsia: hypertension (systolic blood pressure >140 mmHg or diastolic blood pressure >90 mmHg) after 20 weeks’ gestation in a previously normotensive woman plus new-onset proteinuria; and eclampsia: pre-eclampsia plus new-onset grand mal seizures. These criteria were updated in 2013 acknowledging that diagnostic levels of proteinuria may be absent and acknowledging other criteria, including new-onset thrombocytopenia, impaired liver or renal function, pulmonary oedema or cerebral symptoms such as headache and visual disturbance.
‘Women, carers and clinicians need to be educated about the risk of stroke with pre-eclampsia,’ Associate Professor Abbott advised, adding that symptoms of pre-eclampsia and stroke should be discussed as part of routine antenatal care. ‘The postpartum period is a particularly vulnerable time for women, who may ignore symptoms because they are overwhelmed caring for a newborn.’
Stroke 2017; doi: 10.1161/STROKEAHA.117.017374.
Picture credit: © Zephyr/SPL