What's the most important thing people should know about this study as it relates to their health?
One size might not fit all when it comes to blood pressure control. Women appear more affected than men to rises in the systolic blood pressure (SBP), leading to heart attacks, strokes, and heart failure, with SBP readings technically still in the "normal" range of 120-129 mm Hg. Systolic blood pressure is the first number recorded, describing the amount of pressure the blood exerts on the artery walls when the heart beats. Diastolic blood pressure is the second number, and it refers to the amount of pressure exerted between beats.
What was this study seeking to determine? Has this been done before?
Lots of blood pressure studies have been done over the years, including several that have noted the differences between women and men in blood pressure over time. But, this study asks a different question: Are the systolic blood pressure threshold risks the same for women and men? This is a new way to look at blood pressure control that has not been specifically addressed previously by large studies. It is a very important question as we begin to understand the similarities and differences between women and men.
What were the results?
Women started having heart attacks and heart failure when their systolic blood pressure (SBP) was still within the normal range of 110-119 mm Hg. In contrast, men did not develop heart attacks and heart failure until their SBP reached 130-139 mm Hg. This pattern held true for strokes as well.
Did the study reveal any differences concerning subgroups other than sex?
The study analyzed results by age, race, and community, but sex drove the statistical difference in outcomes rather than race or age. However, it is unclear how robust the racial diversity was in the original trials.
What were the strengths and shortcomings of this study's design and execution?
The strengths of this study include:
- Appropriate statistical analysis performed on large, well-done studies
- Large sample size (>27,000 patients)
- Good "apples to apples" comparison of similar groups
- Use of relevant outcomes – heart attack, heart failure, and stroke
However, the study did not evaluate the effect of diastolic blood pressure, but only SBP. It was also an observational study of a large group of people and not a randomized controlled trial, the gold standard of clinical outcomes research, in which subjects are randomly assigned to either an experimental group or a control group. Overall, the study was well done for its design and raises an important clinical question for further research.
What, if anything, should people and health care professionals do differently in the face of these findings?
This study confirms the need for women and their doctors to be quite vigilant about cardiovascular disease (CVD) prevention. While there are some risk factors we can't change, we can change our blood pressure. Know your numbers and work with your health care team to ensure you are meeting current guidelines for blood pressure, lipids, smoking, diabetes, body mass index (BMI), and exercise.
Research scientists also have an opportunity to reexamine the findings in this study, supporting or refuting its results. If we continue to see that women have bad outcomes at lower SBPs, then the current blood pressure guidelines may need to be adjusted. Also, clinical trials should then explore whether lowering the target SBP for women actually prevents CVD and possibly even death.
Finally, the premise of this article – women and men having clinically relevant differences – supports the ongoing journey of precision medicine. Our similarities and distinctions, both genetically and environmentally, represent an important frontier for modern health care. Understanding and then leveraging those distinctions could help us make an even greater difference in the lives of our patients.
HEALTH NEWS IN PERSPECTIVE
Answers to your questions on timely topics in cardiac care to help make sense of research reports in the media. The series includes questions on your heart and the effect of medications, exercise, diet, and hormones.
Team Specialist
Q&A Editor
Heart Health Explained is a collaboration of Women’s Health Research at Yale and the OhioHealth Healthcare System, a nationally recognized not-for-profit organization with providers across 46 counties, offering a holistic approach to prevention, treatment and rehabilitation of heart disease. OhioHealth is staffed by physicians, psychologists, nutritionists and nurses who answer the questions of the moment on heart and vascular health.
The information provided here may help you make more informed choices. However, it is not a substitute for an individualized medical opinion or diagnosis, and everyone should always consult with their personal physicians to make decisions about their condition or treatment.