When assessing a person’s risk for CVD, all results from risk markers should be considered, even when they place the person in different risk categories. This is especially important when assessing residual risk. Below is an example that demonstrates the importance of considering multiple ion mobility-derived risk markers.
Pattern A is classified as optimal, and pattern B is classified as high-risk. This is based on large population studies showing that people without coronary heart disease tend to have an abundance of large, buoyant LDL particles (pattern A), and people with coronary heart disease tend to have an abundance of smaller, dense LDL particles (pattern B).5
However, the literature suggests that CVD risk is conferred by a trio of factors that define the atherogenic lipoprotein profile (ALP).9 The ALP includes elevated small LDL particles (pattern B), low levels of HDL-cholesterol, and often an elevated fasting triglyceride concentration. Thus, the LDL pattern phenotype is only one aspect of the ALP. Additionally, neither the LDL pattern phenotype nor the ALP reflects risk associated with HDL subclasses or the number of small LDL particles. For an example of how LDL particle number can contribute to the overall CVD risk assessment, consider a patient with an optimal pattern A LDL phenotype and a high total LDL mass. If the number of small LDL particles is also high, the patient may be at increased risk despite the favorable pattern A result. Thus, quantitating lipoprotein subclasses (ie, small, medium) can provide important information when assessing overall CVD risk. Interpreting the favorable pattern A result as indicative of low CVD risk could mistakenly rule out treatment in a patient who could benefit from it.