Your doctor will diagnose you with high blood cholesterol based on blood tests of your cholesterol levels, your medical and family history, and a physical exam. Your doctor may do other tests to assess your risk of complications from high blood cholesterol.
A lipid panel usually measures total cholesterol, LDL cholesterol, and HDL cholesterol. Your test may also show the level of non-HDL cholesterol, which includes LDL and all other types of “bad” cholesterol that raise your risk of atherosclerosis and complications.
Your doctor may diagnose you with high blood cholesterol if your total or non-HDL cholesterol level is higher than what is healthy for you. Your doctor might also find that your level of “good” HDL cholesterol is too low.
Your doctor may ask that you fast before a lipid panel. This means you do not eat or drink anything except water for 9 to 12 hours before your blood is drawn. Ask you whether you should take your usual medicines before the test and if there are any other special instructions.
Your doctor may order other tests to help decide whether medicines are needed to lower your risk of heart and blood vessel diseases. These may include a coronary calcium scan, and blood tests for levels of C-reactive protein (CRP) and lipoprotein-a.
Your doctor will ask about your eating habits, physical activity, family history, medicines you are taking, and risk factors for heart or blood vessel diseases.
During your physical exam, your doctor will check for signs of very high blood cholesterol, such as xanthomas, or signs of other health conditions that can cause high blood cholesterol.