Health and medicine
- What is hypertension?
- Intro to hypertension (Pressure, flow, and resistance)
- Intro to hypertension (systolic and diastolic blood pressure)
- Stages of hypertension
- Hypertension types and causes
- Primary hypertension
- Secondary hypertension
- Hypertension effects on the blood vessels
- Hypertension and blood vessel damage
- Hypertension effects on the heart
- Hypertension and heart damage
- Complications of hypertension
- Hypertensive crisis
- Diagnosis of hypertension
- Treatment of hypertension
- 4 lifestyle changes to help manage hypertension
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- Would very high blood pressure also cause chest pain or internal bleeding because of the heart having to work so hard?(5 votes)
- [Voiceover] All right. So, the most common type of hypertension is called primary hypertension. This accounts for about 90 to 95% of all cases. And there's a less common type that accounts for the rest, and that's called secondary hypertension, that we'll get into a little more in-depth in a later video. But, for now, let's just focus on this primary hypertension. So, what is it? Well, we call it primary hypertension when there's actually no known cause, usually because it develops gradually over a long period of time. It seem a little weird, though, right, that for such a high percentage, we don't know exactly what caused this high blood volume or high resistance in the blood vessels that leads to a high blood pressure. But one thing we do look for, though, that helps us get an idea of how it might have cropped up, are called risk factors, which are basically like conditions or habits that make someone much more likely to develop a certain disease, like hypertension. Since primary hypertension typically develops gradually over time, increasing age actually, in itself, is considered a risk factor. High blood pressure becomes more common after age 45 in men and age 65 in women. A second, little more tangible risk factor, one that shouldn't come to much of a surprise, is smoking or even chewing tobacco. Not only do these immediately raise your blood pressure temporarily, but the chemicals found in tobacco can actually damage the lining of your artery walls or your plumbing system, right, which increases the resistance in your vessels and therefore increases your blood pressure. Not only that, second-hand smoke can also have the same effect of increasing your blood pressure. Smoking, therefore, is not good for your blood pressure or, really, anything else for that matter. Another risk factor, sort of along the same lines, is drinking too much alcohol. Having more than three drinks in a single sitting can, just like smoking, temporarily raise your blood pressure. And repeated binge-drinking over time can also damage your heart, making that heart a less-efficient pump. And if it's not pumping as efficiently, your body tries to increase the pressure in your blood vessels to sort of compensate. With that said, drinking alcohol should be done only in moderation, which, in general, is considered no more than two drinks per day for men under 65 and no more than one drink per day for men over 65 and women of all ages. But let's remember to keep in mind that alcohol contains calories that may contribute to weight gain, right, which kind of segues us into the next major risk factor, which is obesity. The more you weigh, the more blood you need to supply your body with oxygen and nutrients. If you remember, trying to jam more blood into the pipe, so your blood vessels, tends to increase what we call the flow, which in turn increases the pressure on your artery walls, and therefore, your blood pressure. And so, another one that sort of plays off of obesity and even can contribute to obesity is not being physically active. Physical activity helps train your heart to be more efficient and get stronger. Without it, your body tries to compensate for a weaker heart and weaker circulation, just like the heavy alcohol consumption, by increasing the pressure in your blood vessels. Another risk factor is poor diet, specifically one that's very high in sodium or salt, because we know that fluid tends to follow salt, right? So, if there's more salt in your body, your body's going to retain more fluid, which is going to, in turn, increase your blood pressure. Now, most of the risk factors that I've mentioned so far seem like pretty controllable risk factors, right? One that tends to contribute to hypertension and is a little more out of your control is actually genetics. Just like hair and eye color can sort of run in your family, so too can hypertension. So, if your mother or your father has hypertension, you or your siblings have a higher risk for hypertension. So, that means it's all the more important to keep all these risk factors in check, right? Another genetic factor, one that might be a little more surprising, is that those of African American heritage tend to have what's called salt sensitivity, meaning that they retain more sodium and water, meaning that, again, it's more important to keep risk factors like diet and salt consumption in mind. So, these are all sort of lumped into primary hypertension, right, where there's no known identifiable cause. If there is an identifiable cause, it's called secondary hypertension. For example, if someone has an underlying kidney disease which causes them to hold on to more water and raises your blood pressure, we would call that secondary hypertension, because we know exactly why it's raising the blood pressure. But, again, let's talk about that a little more in a later video. For now, let's quick-talk about the signs and symptoms of hypertension. What's crazy about this, though, is that most often, there aren't any. Many patients don't even know they have hypertension. Since there usually aren't any signs or symptoms, you might hear it referred to as a "silent disease" or sometimes even a "silent killer." So, that's why when you go in for your annual physical exam, a blood pressure measurement is so important and is always included. If your blood pressure is extremely high in rare cases, then symptoms may appear and can include things like headache, blurred vision, dizziness, and disorientation.