1. A method of determining whether a subject with elevated concentrations of very large high density lipoprotein (HDL) particles (HDL-P) is at increased risk for a cardiac event and/or CHD, comprising: programmatically calculating at least one HDL interaction risk parameter associated with HDL content of a blood plasma or serum sample of the subject, the at least one HDL interaction risk parameter comprising at least two of HP VS , HP ML , and HP VL , where HP VS is a concentration of very small HDL-P subclasses, HP ML is a concentration of medium and large HDL-P subclasses, and HP VL is a concentration of very large HDL-P subclasses.