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Current time:0:00Total duration:5:41

Video transcript

with primary hypertension you've got this high blood pressure and well ultimately the cause is unknown right we've got this big laundry list of risk factors that might contribute but really we don't know exactly what did it with secondary hypertension the differences we know exactly what's causing your blood pressure to rise and we can pinpoint this other medical condition so the hypertension happens secondary to some other disease this form of hypertension accounts for only about 10% of hypertension cases and so it's not that common right whereas the other 90% have primary hypertension so let's sort of just dive right into some of the common diseases that can lead to hypertension all right so renal diseases tend to be big time culprits for secondary hypertension where when we say renal we're referring to the kidneys with these the kidneys don't function as they normally do so since there are such huge players in regulating blood pressure through water and sodium regulation if you've got some kind of underlying kidney problem it can result in this inability to get rid of some fluid and so more fluid in your body leads to higher plasma and blood volume and so higher blood pressure because remember flow and resistance in the blood vessels is directly related to blood pressure so if you increase flow you increase blood pressure and one potential culprit for kidney diseases is polycystic kidney disease by looking at poly we know that that means many right and cystic refers to cysts which I like these fluid-filled sacs so this is an inherited condition where you develop these fluid-filled sacs all around your kidneys and if these guys get too big or there are too many of them they can start to damage or disrupt your kidneys function which can cause you to hold on to more fluid and this will increase your blood pressure another renal disease is glomerular disease and your glomeruli in your kidneys are like these filters for waste in salt or sodium if these filters get swollen or just start working like they normally do this can also increase your plasma volume and increase your blood pressure finally you've got Reno vascular hypertension where Reno refers to your kidneys right and vascular are like the arteries that supply your kidneys with blood so Reno vascular hypertension is usually due to some kind of narrowing of your arteries that supply your kidneys with blood if and when these get narrow they can't supply the kidneys with enough blood right when this happens your kidneys think that there's not a lot of blood in your body and that maybe you're just dehydrated or something and then they respond by trying to hold on to more fluid instead which as we know causes your blood pressure to go up okay so those were all having to do with your kidneys but it doesn't always stem from the kidneys Cushing's syndrome for example has been known to cause secondary hypertension as well with Cushing's syndrome you've got these high levels of circulating glucocorticoids which are like these steroid hormones made by our adrenal cortex so you've got all these glucocorticoids floating around in your bloodstream and these facilitate sodium and water retention which increases your plasma volume and your blood pressure another disease is called primary aldosterone ism this is where some factor some thing may be like a tumor causes your adrenal gland to release too much aldosterone so this time you've got all this aldosterone circulating around your bloodstream and what does that do well it heads straight over to the kidneys and tells them to hold on to sodium and water as we know all too well by now this increases your plasma volume and so your blood pressure the next one's a bit of a mouthful it's pheochromocytoma and this one again is a tumor that grows in the adrenal glands which are also responsible for releasing hormones like norepinephrine and epinephrine which regulate your fight-or-flight response and can temporarily raise your blood pressure another one that's pretty important that you should be aware of is actually sleep apnea seems a little weird right well with sleep apnea your breathing keeps like starting and stopping while you sleep if you do this over and over and over again all night long you end up not getting very much oxygen when you don't get enough oxygen your heart tries to pump harder and deliver more oxygen which tends to sort of increase your flow at night and therefore your blood pressure so it's not uncommon to see a higher blood pressure at night for patients with sleep apnea obesity though it's also a risk factor for primary hypertension can be a lone cause of secondary hypertension as well since as your body weight increases so does the amount of blood circulating around your body this added plasma volume increases your flow and therefore increases your blood pressure and finally there's brain tumors and encephalitis both these brain tumors and the inflammation of the brain or aka encephalitis caused an increased pressure in your skull this tends to decrease your blood delivery to parts of the skull like your brain pretty important and since your brains so important your body tries to increase your blood pressure as well to sort of overcome this pressure in the skull and force more blood up into the skull and into the brain