Low-density lipoprotein cholesterol levels are calculated as milligrams of LDL cholesterol per deciliter of blood, the American Association for Clinical Chemistry explains. A level of 100 milligrams per deciliter or less is considered optimal, while a level of 160 milligrams per deciliter or above is high.
LDL cholesterol levels are the strongest indicator of heart disease risk among all cholesterols in the blood, AACC states. As a result, LDL cholesterol levels are typically used in making decisions about the course of heart disease treatment. They are sometimes observed to monitor the effectiveness of a diet or exercise regimen, for example, or the effectiveness of a specific course of drugs.
LDL cholesterol levels are typically performed as part of a lipid profile test, which is a comprehensive test designed to evaluate the risk of heart disease, AACC explains. In addition to assessing the effectiveness of treatment programs, lipid tests are also ordered as part of regular physical exams for children and adults. Regular testing in five-year intervals is recommended for adults. In addition, the American Academy of Pediatrics recommends a routine test between ages 9 and 11, followed by another between 17 and 21. Children at risk of developing heart disease due to family history of heart disease, high blood pressure, excessive weight or diabetes should undergo testing between ages 2 and 8.