New research highlights lifelong consequences of high blood pressure in pregnancy

A new study has found that women who suffer from high blood pressure in pregnancy, including conditions such as preeclampsia, have an increased risk of developing heart disease and stroke in later life, underlining the importance of early intervention for these women.

High blood pressure in pregnancy affects up to 10 per cent of pregnancies often causing complications in the woman and requiring early delivery of their baby.

The research was led by Dr Fergus McCarthy, Consultant in Obstetrics and Gynaecology at Cork University Hospital and researcher at the INFANT Research Centre in University College Cork, while he was working at King’s College London in the UK.

For the study, Dr McCarthy and his team analysed electronic UK health records from 1997 to 2016 to recreate a UK population-based group of 1.3 million women covering nearly 1.9 million pregnancies. They then looked at the links between those women who suffered from high blood pressure in pregnancy, including preeclampsia and 12 cardiovascular disorders.

During the 20-year study period a total of 18,624 cardiovascular events occurred (such as heart attacks, stroke, heart failure), of which 65 per cent occurred in women under the age of 40.

Women who had one or more pregnancies affected by preeclampsia or other types of high blood pressure in pregnancy were more likely to have a stroke, heart attack, heart failure, or similar event.

Women with pregnancy related high blood pressure had twice the number of deaths in the 20 year follow up period from cardiovascular disease compared with women without pregnancy related high blood pressure. These women also developed chronic hypertension 4.5 times faster than women who did not suffer from high blood pressure in pregnancy.

The increased risk of cardiovascular disease that occurred in the women with previous pregnancy related high blood pressure was found as early as one year after pregnancy compared to pregnant women without the condition.

A total of 8,938 lives were lost to heart disease and stroke in Ireland 2018 and of these 4,140 were due to ischaemic heart disease and 1,680 to cerebrovascular disease or stroke. Of the 4,140 lives lost to ischaemic heart disease the cause of death in 1,740 people was “acute myocardial infarction” also known as a heart attack.

Lead author of the study, Dr McCarthy said, “This research further supports the evidence that what occurs in pregnancy has lifelong implications for a mother’s health. By looking at pregnancy outcomes, we may have an excellent opportunity to identify women at high risk of cardiovascular disease and offer them early interventions after pregnancy to try and reduce this risk. It is critical now that we focus our research on potential interventions to improve the long-term health of mothers.”

Professor Lucy Chappell, Department of Women and Children’s Health, King’s College London said, “These results clearly show that we should now look at how we share this information with women who have had pregnancy hypertension, and that we need to find out what interventions work for these women so that they can reduce their risk of heart disease later in life. It is essential that we work with women and all the healthcare professionals involved in their care so that we can tailor the interventions appropriately to this period of a woman’s life.”

Commenting Dr Angie Brown, Medical Director of the Irish Heart Foundation said, “This important research shows women with high blood pressure in pregnancy, have an increased risk of developing cardiovascular disorders later in life, including stroke and heart failure. This highlights the need for follow up of patients in high risk groups such as the women identified here. Early identification and aggressive treatment of cardiovascular risk factors is crucial in these patients and will reduce the risk of future cardiovascular events.”

The next steps in this research are to determine what interventions, such as diet modifications, salt reduction, exercise or medications that may protect the heart, may work in the women after pregnancy to try and reduce this risk and improve long term health.

This study was published recently in the journal Circulation

(Circulation. 2019;140:1050–1060. DOI: 10.1161/CIRCULATIONAHA.118.0380801050)