If you have been diagnosed with high blood pressure (hypertension), you may be primarily concerned about your risk of cardiovascular disease or even a stroke. And while hypertension is a major risk factor for stroke, it can also lead to brain health problems in other ways.
Psychiatrist Christopher Celano, MD, associate director of the Cardiac Psychiatry Research Program at Massachusetts General Hospital, says the connection between hypertension and brain function isn’t entirely understood, but there is no denying the importance of this often-delicate and quite vulnerable relationship.
“Poorly controlled high blood pressure can significantly affect brain health,” he says. “Research suggests that poorly controlled high blood pressure during mid-life (adulthood) is significantly associated with the development of memory problems or dementia years later. While we are not certain how this occurs, several different mechanisms have been proposed to explain this relationship.”
WHAT YOU CAN DO
- Buy a home blood pressure monitor, and note any changes in your blood pressure. Take the monitor to your doctor’s office to learn how to use it correctly and for advice on how often to check your blood pressure.
- Lose weight if you are overweight and have hypertension. You could see changes in your blood pressure after losing just a few pounds.
- Aim for 150 minutes a week of moderate-intensity aerobic exercise.
- Eat a diet rich in fruits, vegetables, whole grains, and lean proteins. Watch your sodium intake, and consider boosting your potassium consumption, as it may help lessen the effects of sodium on blood pressure.
- Get seven to eight hours of sleep each night. If you are having trouble sleeping, tell your doctor or consider seeing a sleep specialist. It may be a simple fix, such as a change to your sleep hygiene or getting a new mattress. Or it could be a condition such as obstructive sleep apnea that may require treatment to improve your sleep and your blood pressure.
- Take your blood pressure medications exactly as prescribed. Don’t stop taking them without first discussing it with your doctor.
Blood Flow to the Brain
First, Dr. Celano explains, high blood pressure can lead to stiffness and other changes in the arteries in the brain that ultimately may reduce blood flow to the brain, which can affect how it functions.
“High blood pressure also can lead to tiny strokes thatÑwhile they do not immediately cause symptomsÑcan eventually lead to changes in thinking over time,” he says. “Finally, high blood pressure has been linked to an increased deposition of beta amyloid, a peptide that has been implicated in Alzheimer’s disease and other memory problems. So, it is very important to make sure your blood pressure is kept in a normal range.”
For most adults, a normal or healthy blood pressure means a systolic pressure (top number) of less than 120 mmHg and a diastolic pressure (bottom number) of under 80 mmHg. A systolic blood pressure reading of 120 to 129 is considered elevated or pre-hypertensive, while a systolic blood pressure reading of 130 to 139 is considered stage 1 hypertension.
The cutoff for hypertension used to be a systolic reading of at least 140 mmHg, but in 2017, a panel of heart experts decided that more lives could be saved if patients were advised to bring their blood pressure down to 120/80 or lower.
What About Hypotension?
Aggressive blood pressure treatment, though it can save a life, can also bring about new heart-brain risks. Low blood pressure can lead to insufficient circulation to the brain, causing episodes of lightheadedness and fainting. Not surprisingly, low blood pressure resulting naturally or from strong antihypertensive medication treatment can cause thinking and concentration problems.
“As with many things, too much or too little of something can be a bad thing,” Dr. Celano says. “So, while having high blood pressure is bad, low blood pressure can be a problem as well. Your brain uses a lot of oxygen and energy, so it needs to get a good amount of blood to work well. If it is not getting enough blood, you may start to feel lightheaded, dizzy, or nauseated, and you may not be able to think clearly.”
Your blood pressure can drop for a number of reasons. It can occur if you are not drinking enough water and get dehydrated or if your blood pressure medications are being changed in some wayÑeither starting a new medication or changing the dose. “In these situations, it is important to let your doctor know about your symptoms to determine whether your medication needs to be adjusted,” Dr. Celano says.
Mood and Circulation
It’s not just thinking skills, alertness and stroke protection that rely on well-controlled blood pressure.
“Depression can significantly increase one’s risk of developing cardiovascular disease, such as coronary artery disease or heart failure,” Dr. Celano says. “If you have heart disease, depression can make it harder to recover from an acute heart problem, such as a heart attack. While there may be some biological reasons why this may occur, a big part of it also seems to be related to engaging in healthy behaviors that are important for cardiac health.”
When you are feeling depressed, it can be very difficult to do what you need to do to recover from a heart problem, like take medications, be physically active, and have a healthy diet, Dr. Celano says.
“Fortunately, some studies suggest that treating depression can improve heart health,” he adds. “So, if you or a loved one are feeling depressed, it can be important for your mental health and heart health to tell your doctor.”
Dr. Celano warns that managing high blood pressure presents a unique challenge, because there are no obvious symptoms associated with the condition. Some people are hesitant to take their blood pressure medications because they feel fine. However, high blood pressure especially when it is untreated over a long period of time increases the risk of stroke and other serious health complications. So, keeping your blood pressure under control will be beneficial in the long run.
“In addition to taking medications, being physically active and having a healthy diet can also make a difference in both blood pressure and the risk of developing heart disease,” Dr. Celano says. “So, having a healthy lifestyle is important too.”