Beyond Traditional Calculated Cholesterol Testing: Advanced Direct Measurement of Lipids and Lp(a), the Ingerited Independent Risk Factor Atherothrombogenosis in Comparison to HDL and LDL

Background: Lp(a) is a low-density lipoprotein particle in which an apolipoprotein B is linked by a disulfide bridge to a unique glycoprotein. Basic research indicates that Lp(a) has a vital role in atherothrombogenesis. In addition to the well-established cardiovascular risk factors of elevated total and low-density lipoprotein cholesterol, hypertension, cigarette smoking, insulin resistance, obesity, and multiple additional factors are suspected culprits in both the development and the progression of atherothrombosis. Lp(a) is a known independent risk factor for cardiovascular disease; however, its use in clinical utility remains undecided. Design: The institutional review board of Pacific University approved this study. This study compared the associations of Lp(a) and LDL, HDL, total cholesterol, triglycerides, homocysteine, pattern type, and CRP with a wide array of well known traditional risk factors. This retrospective chart review was based on convenience sampling, where the participants were recruited based on provider selection to receive a VAP test (advanced lipid test). Setting: This study was completed at Queen Anne Family Medicine, Seattle W A. Subjects: All patients that were billed and received YAP testing at QAFM between the dates of September 2004 to May 2005 and that met the inclusion criteria for the study were included in the study, n=131. Study subjects were of both genders and were age 18 or older. Objective: It is postulated that the end data will demonstrate the need for advanced lipid profiling, especially in patients with more than two known cardiovascular disease risk factors such as family history of early-onset cardiovascular disease, and to look beyond calculated LDL and HDL values. Results: Using population statistics, base line information was obtained for the entire subject population including gender, age, ethnicity, provider, weight, smoking status, diabetes, related family history, related personal history, related hospitalizations, angina, CABG or revascularization procedures, previous diagnosis of hyperlipidemia, diet, physical activity, alcohol intake and then all data collected from the V AP test such as total cholesterol, LDL, glucose, lIDL 2, lIDL 3, triglycerides, CRP, Lp(a), homocysteine and pattern type. Using the Pearson Product-Moment Correlation (for continuous variables) and Spearman Rank correlation coefficient (for discrete variables) the variables were analyzed with Lp(a) elevations according to result subgroups. Family history of coronary related events, personal history of coronary events, CABG/revascularization procedures, documented ischemia, diabetes mellitus, elevated LDL and total cholesterol had positive associations with elevated concentrations of Lp(a). While all other variables revealed no such relation with elevated Lp(a). Conclusions: This data supports the use of Lp(a) , lipoprotein levels in those patients known to have previous risk factors for cardiovascular disease especially a strong family history, personal, history, diabetes mellitus, or even personal history of dyslipidemia. With the use of good clinical judgment, a multifactorial approach to cardiovascular assessment is prudent and thus advanced lipid profiling would allow health care providers to determine risk beyond those methods traditionally used