The number of individuals in the U.S. with chronic hypertension or chronic high blood pressure during pregnancy doubled between 2008 and 2021, while the prescribing and filling of antihypertensive medication during pregnancy remained low but stable at 60%. Chronic hypertension in pregnancy is defined as high blood pressure diagnosed before pregnancy or before 20 weeks of pregnancy, and recent research has shown that medication treatment of mild or moderate high blood pressure during pregnancy can reduce the risk of severe hypertension and preeclampsia. Preeclampsia, which typically starts after 20 weeks of pregnancy, can cause liver or kidney damage and may increase a woman’s future risk of heart failure and other cardiovascular complications.
In 2017, clinical guidelines from the American Heart Association and the American College of Cardiology revised the thresholds to diagnose high blood pressure, with the guideline recommending medication treatment for adults with stage 2 high blood pressure and individuals with stage 1 high blood pressure who have certain risk factors. Despite these recommendations, a study found that there was no significant change in the rate of medication treatment for high blood pressure during pregnancy, which remained at 60%. This suggests that many patients may not be receiving the appropriate treatment according to clinical guidelines.
The researchers analyzed data from a database of private health insurance claims from 2007 to 2021 and found that the rate of high blood pressure diagnosis during pregnancy steadily increased from 1.8% to 3.7%. The study also found that a higher proportion of individuals with high blood pressure were older, lived in the Southern U.S., and had other chronic health conditions such as obesity, diabetes, or kidney disease. The use of medication for high blood pressure treatment during pregnancy remained low and relatively stable at 57% to 60%.
The study highlighted the need to address the growing burden of chronic hypertension and poor cardiovascular health pre-pregnancy as critical targets to improve maternal health. With nearly 1 in 3 individuals with chronic hypertension at risk for pregnancy complications, prevention and control of hypertension should be a top priority for improving maternal health. The data from the study are consistent with prior studies that have shown an increasing prevalence of hypertension during pregnancy in the U.S.
The study design involved analyzing a database of private health insurance claims that included information on oral antihypertensive medications dispensed by outpatient pharmacies, patient characteristics, and medical conditions. The study had several limitations, including the lack of information on whether prescriptions were taken as directed and the absence of blood pressure measurements in the database. The findings may not be generalizable to individuals with different types of health insurance or living in other countries with different healthcare systems.
Overall, the study highlights the need for better adherence to clinical guidelines for the treatment of high blood pressure during pregnancy, as well as the importance of addressing chronic hypertension and poor cardiovascular health pre-pregnancy to improve maternal outcomes. The researchers emphasize the critical role of prevention and control of hypertension in improving maternal health and reducing the risk of pregnancy complications associated with high blood pressure.