Low-density lipoprotein (LDL-cholesterol) is a type of protein that carries the cholesterol particles in the blood. The test is most often ordered as part of the lipogram and is then calculated based on the values of the other parameters and rarely measured directly.
Maintaining healthy levels of cholesterol is important to prevent long term cardiovascular complications. The body produces the required cholesterol however diet can also become an important source. For those with a family history (inherited predisposition for high cholesterol levels) or when the daily diet contains and excess of foods that are high in saturated fats, the blood level of cholesterol may increase and could negatively impact the person's health. Excess cholesterol may be deposited in plaques on blood vessels walls that could narrow or block the opening of blood vessels (atherosclerosis - hardening of blood vessels). Atherosclerosis has been associated with cardiovascular disease complications including heart attack and stroke.LDL-cholesterol is often called "bad" cholesterol that is associated with deposit of cholesterol in tissues and organs compared to HDL- cholesterol that is often called "good" cholesterol assist with carrying excess cholesterol for disposal. The LDL-cholesterol is used to determine the risk for cardiovascular disease and guide treatment options for those with established risk which include lifestyle changes (e.g. diet and exercise) or medication (lipid-lowering agents/statins). The results of a standard lipogram which includes total cholesterol, HDL-cholesterol and triglycerides are usually used to calculate the LDL-cholesterol level.
Cholesterol testing should be done in all adults with no known risk factors at least once every four years as part of a general risk assessment for cardiovascular complications.
Cholesterol testing should be done more frequent, often bi-annually when a person has one or more risk factors cardiovascular disease which may include:
Adolescents and children
Screening for abnormal cholesterol is recommended between 9 - 12 years and 17 - 22 years of age. More frequent screening is indicated for those at increased risk for cardiovascular disease and complications similar to adults.
Testing may be performed at more frequent intervals as part of monitoring therapy (lipid-lowering lifestyle changes e.g. exercise and dietary changes and specific medication known as lipid-lowering agents/ statins)
For patients who start on medical therapy it is recommended to do the lipogram test after 4 - 12 weeks and again at 3 months to determine effect.
Monitoring may be guided by the medical practitioner who prescribed the therapy.