Understanding your blood pressure numbers
Having healthy blood pressure is important to keep blood flowing normally from the heart to the body’s organs and tissues. It is normal for your blood pressure to rise and fall throughout the day; however it can damage your heart and trigger health problems if it stays high for a long period of time. Unfortunately, nearly half of the adults in the United States (47%, or 116 million) have hypertension (high blood pressure) or are taking medication for it.
Paying attention to your blood pressure is a critical part of staying healthy. Dr. Ourania Preventza, cardiac surgeon and professor in the Division of Cardiothoracic Surgery, shared how to better understand your blood pressure numbers and how they may change over time.
Q: What do the systolic and diastolic numbers mean and which one is more important?
A: First, when we talk about blood pressure, we need to know what normal is; normal blood pressure is 120 mmHg/80 mmHg. The upper number (120 mmHg) is the systolic blood pressure, and the lower number (80 mmHg) is the diastolic blood pressure. Both numbers are important; the systolic blood pressure indicates how much pressure the blood is exerting against the artery walls when the heart beats. The lower number, the diastolic blood pressure, indicates how much pressure the blood is exerting against the artery walls between heart beats, when the heart rests. As we age, the systolic blood pressure rises steadily due to increased stiffness in large arteries so maintaining a healthy lifestyle and diet is important.
Q: What health problems are linked to high blood pressure?
A: Multiple health threats can be associated with high blood pressure, or when blood pressure is not well controlled. It can cause damage to the entire body years before obvious symptoms occur. Over time, the body’s arteries lose their elasticity and become stiffer. The arteries can also get narrow, which can limit the blood flow going through them. Constant high blood pressure in a section of an artery can also create a bulge, which is called an aneurysm. Because of these conditions, some of the health problems associated with high blood pressure are stroke, eye problems, heart problems such as heart attack and heart failure, poor quality of life, kidney damage, sexual dysfunction or even sudden death.
Q: Are there symptoms?
A: Some of the symptoms include chest pain—because of the limited blood flow through the main arteries of the heart—and irregular heartbeat with lightheadedness, severe back pain, faintness, temporary vision loss, temporary facial numbness or the temporary inability to move upper or lower extremities. If these symptoms persist, then a stroke can occur. Additionally, limiting blood flow to the brain can cause vascular dementia over the years or mild cognitive impairment.
Shortness of breath is another symptom that can happen because of fluid buildup in the lungs and the inability of the kidneys to filter excess fluid from the blood. In addition to shortness of breath, the person will see abnormal swelling of their lower extremities and their body will retain more fluids. Regarding the eyes, bleeding within the eye, blurred vision or vision loss can occur. The risk is higher in patients who have diabetes (high blood sugar) in addition to high blood pressure. Erectile and sexual dysfunction for both men and women can occur after years of high blood pressure.
Q: While low blood pressure may sound desirable, can hypotension also cause health issues?
A: Hypotension can cause issues when it is associated with fainting, dizziness, fatigue, nausea and the inability to concentrate. Hypotension can be orthostatic where a person feels faint when they stand up or change position abruptly. Hypotension can also occur after eating a meal (postprandial hypotension), after exercising or after standing for a long time in the same position. The most extreme form of hypotension is shock. When a person is in shock, the body does not get enough blood to function; this can be detrimental and can even lead to a person’s death.
Q: When is high blood pressure an emergency?
A: It’s an emergency when sudden chest or back pain occurs; heart attacks, stroke, loss of vision and loss of consciousness should also be treated as emergency medical situations. Also, pregnant women should be alert if they have high blood pressure because of potential pregnancy complications such as eclampsia or preeclampsia.
Q: How is high blood pressure treated?
A: Lifestyle changes and treatment are important if someone has high blood pressure. For example, drinking too much alcohol can raise blood pressure to unhealthy levels. Eating a healthy low-salt diet, physical activity, maintaining healthy body weight and avoiding smoking are all important lifestyle choices that will help blood pressure levels and promote a good quality of life. Checking your blood pressure regularly and treating it with your physician’s guidance if it’s high is important. Early and better treatment can be achieved with the patient being part of the healthcare team and listening to their doctor’s recommendations.
-By Bertie Taylor, senior writer in the Michael E. DeBakey Department of Surgery at Baylor College of Medicine