There is a point when discussing blood pressure, cholesterol or weight control that patients are genuinely perplexed about what causes what.
There is a very common notion that hard arteries or obesity both cause high blood pressure. It makes a certain amount of sense, when you think about it, but it’s unfortunately not true.
That’s why it’s well worth understanding this stuff as atherosclerosis is the leading cause of death and poor health in this country. As luck would have it, many cases of arteriosclerosis are fixable.
Atherosclerosis is commonly called “hardening of the arteries,” but the real problem is blockage of the arteries. Two hundred years ago, which in medicine might just as well be a million years, people dissecting dead bodies discovered arteries that were hard as pipe. These thick, hard walls were the result of calcified cholesterol plaques in the wall in arteries, thus the idea of “hardening of the arteries.”
We care a lot less about hardness than lousy blood flow. What happens when blood doesn’t flow? The body part turns black and dies – that’s bad.
So atherosclerosis means not enough blood to whatever the artery supplies – in the heart, no blood means a heart attack; in the brain, a stroke; in the kidneys, kidney failure. The list goes on, so we want to avoid atherosclerosis.
Many modifiable risk factors work through atherosclerosis to do their damage. High blood pressure (hypertension) beats up on the arteries by over pressuring them. That causes microscopic tears in the lining of the arteries. The body responds by causing an inflammatory reaction in the blood vessel. Over time this causes cholesterol to reinforce the walls of the vessel. In this case, the reinforcement causes trouble, namely atherosclerosis.
Cholesterol is another modifiable risk factor. By modifiable I mean something can be done about it. In general, the higher the cholesterol, the faster you develop atherosclerosis.
These days we understand that not all cholesterol is bad. There is bad cholesterol that plugs up your plumbing, like saturated fat. To make life more complicated, there are also several types of cholesterol particles. The good guys are called HDLs (high density lipoproteins), which are thought to bring cholesterol back from the plugged blood vessels, improving blood flow. LDLs are the bad guys. They are in the business of plugging blood vessels.
Good news – drinking wine increases your HDLs.
Smoking is another way to accumulate blood vessel damage as quickly as possible. There are chemicals and carbon monoxide in tobacco smoke that injure blood vessels. Once the vessels are injured, they are well on their way to becoming atherosclerotic.
Diabetes is a disease of uncontrolled or poorly controlled blood sugar. Blood sugar that is out of balance damages – you guessed it – the blood vessels. This results in high rates of inflamed and blocked arteries. This is a treatable condition, and careful control of blood sugar measurably reduces the rate of atherosclerosis.
No discussion of “hardening of the arteries” would be complete without mentioning obesity. It is readily apparent after a brief glance around any city in the country that obesity is at nearly epidemic levels. Obesity gets involved with hastening atherosclerosis in a variety of ways. Just being very overweight puts an additional load on the cardiovascular system. This alone can cause damage.
Obesity is also associated with type 2 diabetes. Often, people don’t get extra large eating only low-fat foods, so cholesterol-rich diets are also a factor.
These risk factors work together – smoking, high blood pressure, cholesterol and obesity cause a much greater risk when together in the same patient at the same time. The fancy name for this is metabolic syndrome. For those people, lifestyle changes are essential.
The good news is most of what plugs your plumbing is under your control. A doctor can help you with high cholesterol or blood sugar. You can help yourself by making good dietary choices and getting a little exercise. It might also be a good idea to throw the cigarettes away.