Episode 29: January 6, 2010
by Rob Lamberts, M.D.
What Is Blood Pressure?
In my last article I explained what blood pressure is and what it means when the nurse blows that thing up around your arm and writes down numbers with a horrified expression. This article will cover the problems that happen when blood pressure is too high and what you can do about it.
What Is High Blood Pressure?
So why does the blood pressure get high in the first place? It doesn’t do it just out of boredom; hypertension (which is persistent high blood pressure) happens because of bad influences. Bad influences can make people do things they shouldn’t be doing, like getting tattoos in regrettable places. It’s called peer pressure. Well, think of hypertension as the peer pressure of the blood vessels.
What Affects Blood Pressure?
Here are the bad actors that can lead your vessels down the road to perdition (or at least to higher blood pressure):
The Kidneys – kidneys are supposed to filter the blood and maintain the balance of sodium, potassium, and other substances needed to keep things normal. Good kidneys will react to an increased blood pressure by lowering certain hormones in the blood, getting rid of sodium, or making you pee more . But kidneys gone bad are lazy and let blood pressure go up without raising a finger…or nephron.
The Epithelium – I just can’t get through an article without some fancy Latin or Greek word. The epithelium is a thin coating of cells on the inside of the arteries. These cells, it turns out, are very important in determining if arteries will be narrow and contracted or open and relaxed. They react to the sodium, potassium, and other substances, and change the blood pressure accordingly.
Hormones – these are substances put out by glands--such as the pituitary and adrenal glands--that have effects all over your body. Ideally they are released in response to low pressure, but when hormones go bad they wander around your bloodstream when they shouldn’t be there, when the pressure is normal .
Nerves – Some nerves have the job of relaxing or contracting muscles around blood vessels to keep the blood pressure normal. But some nerves tell the muscles to contract at the wrong time, making the pressure go too high. They’ve got a lot of nerve to do that.
The fact that there are a bunch of different bad influences is what makes treating hypertension so difficult at times; just going after one bad influence may not be enough. You have to get rid of them all in order to get the pressure back under control.
What Causes High Blood Pressure?
So what makes these body parts go bad, causing high blood pressure? Sometimes it’s not their fault, such as when the kidney gets damaged or a hormone gland fails. But for most people, it’s a combination of bad genes and bad environment that makes these body parts choose their sorry path. Bad genes can cause any or all of the control centers for blood pressure to malfunction.
How Can You Prevent High Blood Pressure?
Keep your weight under control, and if your blood pressure is even borderline, cut back on sodium and get enough potassium.
You can’t do much about bad genes besides griping, but you can do a whole lot to control environment, including the following:
Limit sodium: Eating lots of sodium can put a lot of stress on the kidneys and mess up with the epithelium. Click here for a Nutrition Diva episode that can help you there.
Lose weight: Obesity can change the hormones in the body.
Quit smoking: Smoking messes with the nerves that control the blood pressure.
Limit stress: Stress can mess with hormones and nerves.
What are the Risks of High Blood Pressure?
Often the worst consequences of dumb decisions teenagers make are not felt until much later (like that tattoo you know where). The same thing is true with blood pressure. Long-term elevation of blood pressure puts you at much higher risk of lots of bad things, such as:
Kidney damage, and even kidney failure requiring dialysis
Plaque build-up in arteries that can cause heart attacks and strokes
Aneurysms, which are the ballooning of blood vessels to the point where they can burst. The most significant aneurysms occur in the head and the abdomen.
Thickening of the heart muscle, which increases the risk of lethal heart arrhythmias.
There are others, but I think you get the picture. Go after these bad influences early or pay the consequences later.
How Should You Treat High Blood Pressure?
My quick and dirty tips today will tell you what to do about blood pressure.
Tip 1: Get it Checked Regularly
This is the same tip I gave in my last article, but it is worth repeating. You can have dangerously high blood pressure and not know it. A good pressure to aim for is 120/70.
Tip 2: Look for Other Causes
Looking for kidney or hormone problems (with blood and urine tests) are important when hypertension is first diagnosed. This is especially important if the onset is rapid or at a young age.
Tip 3: Watch Your Diet
The Nutrition Diva didn’t pay me to write this (although she can if she wants to). Diet matters. Keep your weight under control, and if your pressure is even borderline, cut back on sodium and get enough potassium; doing so can keep you from needing medications.
Tip 4: Exercise and Stop Smoking
Exercise not only burns calories and lowers weight, it also lowers pressure by itself. A combination of aerobic exercise and weight training is probably best.
Quitting smoking will not only make you stop smelling so bad, it will lower your blood pressure.
Tip 5: If You Need to, Take Medication
There are a bunch of very effective medications for high blood pressure that are inexpensive and have very few side effects. As long as your blood pressure isn’t extraordinarily high, you certainly should first try the lifestyle changes before going on medication. But you should do what you can to treat hypertension early to avoid the consequences.
The medications that treat hypertension generally attack one of the bad influences I mentioned earlier. Many people have two, three, or even four different reasons for the blood pressure elevation, so it often takes more than one medication to bring it back to normal. As always, you should talk to your doctor and find out why each medication you take is important, as well as what side effects you should look out for.
Any medication is a trade off between negatives and positives. With blood pressure, many people don’t feel bad and so don’t take their medication like they should. That is a really bad idea.
Tip 6: Know When to Panic
Usually high blood pressure is not an immediate risk. The exceptions to this rule are:
When the top number gets above 200 and the bottom number over 110, it’s time to get seen immediately. It actually takes a pressure higher than this to cause panic, but you don’t want to go there.
When high pressure is associated with severe headache or chest pain. These mean you may be sustaining damage to your brain or your heart. You don’t want to go there either.
That’s all I’ve got for blood pressure.
If you have questions you want answered, send them to firstname.lastname@example.org. You can find me on Twitter as @housecalldoc and on Facebook under “House Call Doctor.”
Let me remind you that this podcast is for informational purposes only. My goal is to add to your medical knowledge and translate some of the weird medical stuff you hear, so when you do go to your doctor, your visits will be more fruitful. I don’t intend to replace your doctor; he or she is the one you should always consult about your own medical condition.
Catch you next time! Stay Healthy!