Hyperlipidemia, the medical term for high cholesterol, literally means “high lipids in the blood.” Lipid is a general term referring to various kinds of organic fats and cholesterol. Cholesterol and fats in the blood greatly increase the risk of coronary artery disease as well as other types of cardiovascular disease. Since there are no symptoms to experience that would tell you if you might have high cholesterol, the only way to detect it is through screening. Otherwise healthy men should be screened beginning at age 35 while healthy women should begin screening at age 45.
Now that you know what cholesterol is, you may be wondering, “Why does it matter so much?” After all, there are a lot of different things floating around in our blood streams. First, there are two major carriers of cholesterol in the body. You may have heard of “bad” cholesterol versus “good” cholesterol. Bad cholesterol is called low-density lipoprotein or LDL. It is cholesterol that is carried through the blood by a compound known as LDL. This compound, or lipoprotein, is made of fat and protein and specializes in carrying cholesterol to different organs of the body. Good cholesterol is called high-density lipoprotein or HDL. The third kind of cholesterol is called VLDL or very low-density lipoprotein. VLDL is responsible for carrying triglycerides, a certain type of fat, throughout the body. HDL and LDL, on the other hand, carry cholesterol.
The reason it is dangerous to have high levels of cholesterol, LDL, and VLDL in your blood is because these three compounds are a crucial part of building plaques in your arteries. A plaque occurs when the blood vessel becomes injured in some way. This can be from high blood pressure, the chemicals in cigarette smoke, or diabetes. The body responds to this injury by sending white blood cells to the area – this is the definition of inflammation. The white blood cells “ingest” the cholesterol and become large and sluggish; they are called foam cells. Because of the damage to the innermost layer of the blood vessel (endothelium), these foam cells and cholesterol build up between the layers of the artery. Many proteins and chemical signaling agents are involved in the plaque function, but the major contributors are cholesterol and white blood cells.
As the plaque grows, the “cap,” (the damaged inner layer of the artery) becomes unstable. Two consequences may occur. One, the plaque can grow large enough to significantly block the blood vessel. This can result in angina, or transitory chest pain or an actual heart attack. If the blood vessel is in the kidneys and it becomes blocked, it can cause kidney failure. The second consequence is that the whole plaque may rupture and send its contents into the narrowing part of the artery, where it can block blood flow. Again, this can lead to heart attack, stroke, kidney failure or failure of whatever organ receives blood from that blood vessel. Despite the dramatic danger of having large plaques in your arteries, you may not have any symptoms until it is too late.
When to start screening for cholesterol level is a well-studied thing. The U.S. Preventative Services Task Force (USPSTF) is a group of healthcare professionals that looks carefully at all of the medical studies regarding certain preventable chronic diseases and then makes a recommendation for how to screen people for an illness as well as the best way to prevent it. The USPSTF recommends that men be routinely screened for high cholesterol from age 35 and older or from age 20 and older if they have an increased risk of coronary heart disease. Women should be screened beginning at age 45 or at age 20 if they have any risk factors for high cholesterol.
High cholesterol generally does not show any symptoms at first, however; longstanding elevated cholesterol is typically associated with heart disease, stroke and peripheral vascular disease (a blockage of blood vessels in the legs). The exceptions to this are several forms of genetic high cholesterol, which can cause many odd symptoms due to the buildup of cholesterol or lipid in the body. For instance, familial hyperlipidemia, caused by damage to chromosome number 19, causes LDL (bad cholesterol) to be extremely high beginning in childhood. The LDL is so high that it builds up in places like the tendons, elbows, knees, and eyes. These deposits are called xanthomas. These children also tend to have chest pain and coronary artery disease at a very young age.
You will need to control your cholesterol closely, over time even non-genetic hyperlipidemia will cause dangerous levels of lipids to accumulate in your bloodstream. Since you might have no outer symptoms to help you know your cholesterol level, your first symptom could be a heart attack or a stroke. This is why following your doctor’s recommendations when it comes to blood tests and cholesterol screening is extremely important to your health.
High cholesterol can be caused either by a genetic disorder or by poor lifestyle choices. There are also some people who get high cholesterol as a secondary effect from other diseases like diabetes or hypothyroidism. Regarding genetic high cholesterol, there are several different types. Some increase LDL (“bad cholesterol”) while others increase triglycerides (fatty molecules). This happens because various parts of the genome (one whole set of DNA) can be affected. For example, if there is damage to the DNA in one certain area, cholesterol will be very high. Damage to another area may cause only triglycerides to be high. These examples are grouped together and called “Familial Hypercholesterolemia” because they tend to run in families. If you don’t have a striking family history of very high cholesterol, you probably just have regular hyperlipidemia. This is influenced by many lifestyle factors, such as diet, exercise, and BMI (a way to measure weight as proportional to height).
When the doctor tells you, “Your cholesterol is high,” he is actually being quite vague. There are several types of cholesterol in the blood and a normal blood test usually measures at least four. They are as follows:
As mentioned previously, high cholesterol can be a product of poor lifestyle choices or genetic factors, with a small fraction of people having it due to other diseases. Genetic high cholesterol may look a number of different ways. Damage to the DNA may cause excess production of different types of cholesterol or it may even cause dysfunction in how the body removes cholesterol and fat from the blood. One feature that all the genetic lipid disorders share is that they are heritable. This means that if you have one of these disorders, many of your family members in the past and present will have it too.
Typical high cholesterol develops gradually with age and is due to a person’s own choices in life. Risk factors include obesity, lack of exercise, a sedentary lifestyle, cigarette smoking, heavy alcohol use, and a diet high in saturated fat and cholesterol. Similar to other chronic diseases such as type 2 diabetes and high blood pressure, high cholesterol develops due to a derangement of normal metabolism. Having some of each type of cholesterol in your blood is crucial to functioning normally. LDL and VLDL carry cholesterol and triglycerides, respectively, out to parts of the body that need them. For example, cholesterol is used to make steroid hormones, including estrogen, testosterone, and cortisol. It also is an essential part of making bile, which is needed to digest fat in the intestines. The body is capable of making enough of its own cholesterol to accomplish these tasks, but supplementing this with dietary sources of cholesterol is not a problem. The body will simply downgrade how much cholesterol it is making and use the cholesterol from your diet.
The problem is when you have such an excess of dietary cholesterol that your body cannot keep up with disposing of that excess. Then, cholesterol and fatty acid levels will build up in your bloodstream and begin forming plaques on the inner layer of your blood vessels which leads to hardening of the arteries. This hardening is called atherosclerosis. Any amount of atherosclerosis is bad, but as the amount of it increases, your risk of coronary heart disease, heart attack, and stroke increases as well.
As was mentioned above, some people have what is called secondary hypercholesterolemia. This is high cholesterol due to another illness or medication. One example is type 2 diabetes. Those with this disorder may experience a rise in their cholesterol even if they have been eating well and staying in shape. Other conditions that can have this same effect include hypothyroidism, pregnancy, kidney failure, and liver disease. Some medications may also induce high cholesterol levels, such as blood pressure medications, antipsychotic medicines, and oral contraceptive pills. It is important for you, if you have any of these risk factors, to have your cholesterol checked early.
Lifestyle changes are essential to improve your cholesterol level. To bring your numbers down, lose excess weight, eat healthy foods and increase your physical activity. If you smoke, quit.
The goal of treatment is to reduce your risk of having a heart attack, peripheral artery blockage, or stroke. If your cholesterol is only slightly high and/or if you don’t have any cardiac risk factors, your initial treatment will probably be simply making changes to your lifestyle. If you have very high cholesterol, diabetes, smoke cigarettes, or have any of the conditions listed in the “Diagnosis” section as risk factors, your doctor might consider starting you on a medication right from the start.
The benefit of lifestyle changes on high cholesterol may be seen within 6-12 months. If these lifestyle changes are not enough to lower your cholesterol, medication may be required. The reason doctors tend to treat hyperlipidemia so aggressively is because for every 1% reduction in cholesterol level, the risk of heart disease is reduced by 2%. The specific choice of medication or combination of medications depends on several things. These include: