Why is a direct measurement of LDL important?
The NCEP ATP III recommends that LDL be directly measured as a new feature of the guidelines. LDL is not directly measured in todays routine lipid panels. Rather, it is calculated using the Friedewald equation: [LDL] = [total cholesterol] [HDL] [triglycerides/5]. Thus, calculated LDL is falsely low in patients with elevated triglycerides, and it does not correlate well in patients with diabetes, coronary disease, or other atherosclerotic diseases.