Hypertensive disorders of pregnancy and risk of cardiovascular disease in women: electronic cohort study in primary care

Date of Approval: 
2019-09-11 00:00:00
Lay Summary: 
Women who suffer from high blood pressure during pregnancy are at increased risk of future heart disease. Previous research found that women with high blood pressure during pregnancy were more likely to have a future hospital admission for heart attack or stroke compared to women whose blood pressure remained normal during pregnancy. However, some women may present to their GP with persistent high blood pressure or angina and may be diagnosed with heart disease without requiring a hospital admission. Previous research has not looked at when or how women with high blood pressure during pregnancy may subsequently (once pregnancy is complete) present to their GP with early signs or symptoms of heart disease. This is an important gap in our current knowledge because presenting to the GP provides an opportunity for early intervention to prevent serious events such as heart attacks and strokes. This study will analyse routinely collected data from general practices in the UK. We will look specifically at women who have had at least one pregnancy and compare the risk and timings of being diagnosed with persistent high blood pressure or heart disease between women who had high blood pressure during pregnancy and those who did not. We are interested in persistent high blood pressure or heart disease that occurs once the pregnancy is complete. We will look at the characteristics of women who develop persistent high blood pressure or heart disease to understand when, how and who to test for these conditions in women who have had at least one pregnancy. This information could help with earlier diagnosis and treatment of heart disease and prevent serious health events or death.
Technical Summary: 
Preeclampsia affects 4 to 8% of pregnancies. It is a multi-system disorder that can affect subsequent (post-pregnancy) cardiovascular health and is associated with an increased risk of cardiovascular events and mortality. However, the existing evidence base is largely based on hospital admissions data, thus limiting its use for insights into opportunities for early detection and intervention to alter disease progression. Currently, very little is known about the timing of adverse cardiac events in women who have had hypertensive disorders of pregnancy, or the effect of lifestyle modification on their development. This proposal is a retrospective cohort study that seeks to address these gaps in the evidence by analysing CPRD data to estimate the risk and time to onset of incident cardiovascular disease in women who have hypertensive disorders of pregnancy, to inform subsequent strategies for cardiovascular risk assessment and screening in primary care settings. Outcomes of interest are indicators of new-onset cardiovascular disease (hypertension, ischaemic heart disease and cerebrovascular disease) that occur after a completed pregnancy, in a cohort of women who have no evidence in their GP record to suggest a history of cardiovascular disease prior to pregnancy. We will identify the socio-demographic and clinical variables associated with these disorders and estimate the risk of incident cardiovascular disease in women with a hypertensive disorder of pregnancy compared to women without, accounting for socio-demographic and clinical risk factors. The outputs from this project will contribute towards developing a targeted approach using routine data for risk stratification for women who have had hypertensive disorders of pregnancy to assess their cardiovascular risk.
Health Outcomes to be Measured: 
Outcomes of interest are indicators of new-onset cardiovascular disease (CVD) that occur after a completed pregnancy in a cohort of women who have no evidence in their GP record to suggest a history of CVD prior to pregnancy. The specific outcomes are: 1. Hypertension 2. Ischaemic heart disease 3. Cerebrovascular disease
Application Number: 
19_186
Collaborators: 

Shantini Paranjothy - Chief Investigator - University of Aberdeen
Harry Ahmed - Corresponding Applicant - Cardiff University
Hywel M. Jones - Collaborator - Cardiff University
Laszlo Trefan - Collaborator - University of Manchester
Sohinee Bhattacharya - Collaborator - University of Aberdeen

Linkages: 
Practice Level Index of Multiple Deprivation