What do my cholesterol test results mean?
Cholesterol is a form of fat used by your body to make cell membranes. If you have too much in your blood, it can stick to the walls of your blood vessels and result in narrow arteries. This means your heart has to work harder to pump your blood and increases the risk of blood clots, which can cause strokes and heart attacks. Thus doctors often order “Lipid Panel” tests to measure your cholesterol and measure your risk of heart disease.
A lipid panel breaks out your cholesterol into 4 measures:
- Total Cholesterol
- LDL (low-density lipoprotein), also known as “bad cholesterol”
- HDL (high-density lipoprotein), also known as “good cholesterol”
In order to get an accurate measurement, you must fast for at least 8 hours (no food or liquid, except water) prior to your blood draw. If you forget to fast, your results may be distorted and your physician may need to repeat the test. Interpreting cholesterol results is complicated because your risk for heart disease varies based on age and the presence or absence of other related diseases such as Diabetes. In general, your doctor will look at the following:
- Total Cholesterol. Less than 200 is normal. More than 240 is high.
- LDL. This is the most important component. Less than 100 is normal. More than 130 is high. However if you have certain diseases like Diabetes that increase your risk of heart disease or if you’ve already been diagnosed with heart disease, your LDL should be under 70. If you are over age 75, your risk of heart disease is already higher due to age and it is thus more difficult to evaluate your risk based on LDL. You would need to speak with your physician about how your LDL interacts with other risk factors.
- HDL. Unlike LDL, you want your HDL to be high. Greater than 60 is good, between 40 and 60 is OK, and less than 40 increases your risk of heart disease.
- Triglycerides. Less than 150 is normal. Greater than 200 is high.
The American College of Cardiology has developed an online tool used to evaluate your cardiovascular risk, http://www.cvriskcalculator.com/. The tool can give you a quick snapshot of your risk and whether to consider cholesterol-lowering medications such as statins.
Treating high cholesterol starts with Diet and Exercise. Exercise in particular will both lower your LDL and increase your HDL and will also help address other cardiovascular conditions such as Hypertension. Any activity that can move you away from a sedentary lifestyle will help, such as gardening, taking the stairs, or walking. When it comes to Diet, you want to avoid foods that contain saturated and trans fats typically found in red meat and processed foods such as cookies. Instead eat more fresh leafy vegetables. Finally, smoking is one of the highest risk factors for heart disease and quitting, even in old age, can dramatically reduce your risk.
If lifestyle improvements don’t reduce your cholesterol enough or if your risk is very high, then your doctor will probably prescribe cholesterol-lowering medications. There are many choices that offer different combinations of effectiveness, cost, and side-effects and your physician may try different medications before settling on one that works best for you. Most patients who start on cholesterol medication take it for the rest of their lives and will require regular blood testing to monitor effectiveness.