Although levels of LDL ("bad") cholesterol are the primary focus of a cholesterol screening (which also measures total cholesterol, HDL ["good"] cholesterol, and triglycerides), about half of all heart attacks occur in people with normal LDL levels. So researchers have looked at other measurements that can help identify people at risk for cardiovascular disease.
Non-HDL cholesterol is obtained by subtracting the level of HDL cholesterol from total cholesterol. The resulting value measures not only LDL cholesterol, but also cholesterol contained in metabolic "remnants" of very low-density lipoproteins (VLDL), the main carriers of triglycerides. Like LDL cholesterol, these remnants promote the buildup of plaque in arteries. Studies have shown that non-HDL cholesterol is better than LDL cholesterol alone at predicting cardiovascular risk, especially in people with elevated triglycerides.
People with type 2 diabetes often have elevated triglyceride levels but relatively normal LDL cholesterol values, so measuring their non-HDL cholesterol can be useful in assessing their risk and guiding their treatment. One advantage of factoring in non-HDL cholesterol is that it requires no additional testing; it simply can be calculated after a standard cholesterol test.
According to guidelines from the National Cholesterol Education Program, desirable levels for non-HDL cholesterol are 30 mg/dL above target levels for LDL cholesterol. Thus, if you have type 2 diabetes, your level of non-HDL cholesterol should be no higher than 130 mg/dL (since the LDL cholesterol target is 100 mg/dL for anyone with diabetes). If your triglyceride level is above 200 mg/dL, ask your doctor about your non-HDL cholesterol.
