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Background and Aims: Despite growing evidence that apolipoprotein B (apoB) is the most accurate marker of atherosclerotic cardiovascular disease (ASCVD) risk, its adoption in clinical practice has been low. This investigation sought to determine whether low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (HDL-C), and triglycerides are sufficient for routine cardiovascular care., Methods: A sample of 293 876 UK Biobank adults (age: 40-73 years, 42% men), free of cardiovascular disease, with a median follow-up for new-onset ASCVD of 11 years was included. Distribution of apoB at pre-specified levels of LDL-C, non-HDL-C, and triglycerides was examined graphically, and 10-year ASCVD event rates were compared for high vs. low apoB. Residuals of apoB were constructed after regressing apoB on LDL-C, non-HDL-C, and log-transformed triglycerides and used as predictors in a proportional hazards regression model for new-onset ASCVD adjusted for standard risk factors, including HDL-C., Results: ApoB was highly correlated with LDL-C and non-HDL-C (Pearson's r = .96, P < .001 for both) but less so with log triglycerides (r = .42, P < .001). However, apoB ranges necessary to capture 95% of all observations at pre-specified levels of LDL-C, non-HDL-C, or triglycerides were wide, spanning 85.8-108.8 md/dL when LDL-C 130 mg/dL, 88.3-112.4 mg/dL when non-HDL-C 160 mg/dL, and 67.8-147.4 md/dL when triglycerides 115 mg/dL. At these levels (±10 mg/dL), 10-year ASCVD rates for apoB above mean + 1 SD vs. below mean - 1 SD were 7.3 vs. 4.0 for LDL-C, 6.4 vs. 4.6 for non-HDL-C, and 7.0 vs. 4.6 for triglycerides (all P < .001). With 19 982 new-onset ASCVD events on follow-up, in the adjusted model, residual apoB remained statistically significant after accounting for LDL-C and HDL-C (hazard ratio 1.06, 95% confidence interval 1.0-1.07), after accounting for non-HDL-C and HDL-C (hazard ratio 1.04, 95% confidence interval 1.03-1.06), and after accounting for triglycerides and HDL-C (hazard ratio 1.13, 95% confidence interval 1.12-1.15). None of the residuals of LDL-C, non-HDL-C, or of log triglycerides remained significant when apoB was included in the model., Conclusions: High variability of apoB at individual levels of LDL-C, non-HDL-C, and triglycerides coupled with meaningful differences in 10-year ASCVD rates and significant residual information contained in apoB for prediction of new-onset ASCVD events demonstrate that LDL-C, non-HDL-C, and triglycerides are not adequate proxies for apoB in clinical care., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background: Aortic valve calcification (AVC), Lp(a) [lipoprotein(a)], and low-density lipoprotein cholesterol (LDL-C) are associated with severe aortic stenosis (AS). We aimed to determine which of these risk factors were most strongly associated with the risk of incident severe AS., Methods: A total of 6792 participants from the MESA study (Multi-Ethnic Study of Atherosclerosis) had computed tomography-quantified AVC, Lp(a), and LDL-C values at MESA visit 1 (2000-2002). We calculated the absolute event rate of incident adjudicated severe AS per 1000 person-years and performed multivariable adjusted Cox proportional hazards regression., Results: The mean age was 62 years old, and 47% were women. Over a median 16.7-year follow-up, the rate of incident severe AS increased exponentially with higher AVC, regardless of Lp(a) or LDL-C values. Participants with AVC=0 had a very low rate of severe AS even with elevated Lp(a) ≥50 mg/dL (<0.1/1000 person-years) or LDL-C ≥130 mg/dL (0.1/1000 person-years). AVC >0 was strongly associated with severe AS when Lp(a) <50 mg/dL hazard ratio (HR) of 33.8 (95% CI, 16.4-70.0) or ≥50 mg/dL HR of 61.5 (95% CI, 7.7-494.2) and when LDL-C <130 mg/dL HR of 31.1 (95% CI, 14.4-67.1) or ≥130 mg/dL HR of 50.2 (95% CI, 13.2-191.9)., Conclusions: AVC better identifies people at high risk for severe AS compared with Lp(a) or LDL-C, and people with AVC=0 have a very low long-term rate of severe AS regardless of Lp(a) or LDL-C level. These results suggest AVC should be the preferred prognostic risk marker to identify patients at high risk for severe AS, which may help inform participant selection for future trials testing novel strategies to prevent severe AS., Competing Interests: Disclosures None.

Background Elevated lipoprotein(a) is a well-established risk factor for atherosclerotic vascular disease but is not measured in routine clinical care. Screening of high lipoprotein(a) in individuals with moderate elevations of low-density lipoprotein cholesterol (LDL-C) may identify individuals at high risk of cardiovascular disease. Methods and Results We examined 2606 Framingham Offspring participants (median age, 54 years; 45% men) prospectively with a median follow-up of 15 years (n=392 incident cardiovascular events). Individuals with higher (≥100 nmol/L) versus lower lipoprotein(a) were divided into groups based on LDL-C <135 mg/dL versus ≥135 mg/dL. In Cox models, after adjustment for known risk factors, high lipoprotein(a) (≥100 nmol/L) and LDL-C ≥135 mg/dL were each significant predictors of cardiovascular disease (LDL-C ≥135 mg/dL: hazard ratio [HR], 1.34; 95% CI, 1.09-1.64; P =0.006; high lipoprotein (a): HR, 1.31; 95% CI, 1.03-1.66; P =0.026). Across the groups of high/low lipoprotein (a) and LDL-C ≥135 mg/dL or <135 mg/dL, the absolute cardiovascular disease risks at 15 years were 22.6% (high lipoprotein(a)/LDL-C ≥135 mg/dL, n=248), 17.3% (low lipoprotein(a)/LDL-C ≥135 mg/dL, n=758), 12.7% (high lipoprotein(a)/LDL-C <135 mg/dL, n=275) and 11.5% (low lipoprotein(a)/LDL-C <135 mg/dL, n=1328, reference group). Among individuals with LDL-C ≥135 mg/dL, those with high lipoprotein(a) had a 43% higher risk (HR, 1.43; 95% CI, 1.05-1.97; P =0.02). Presence of high lipoprotein(a) with moderate LDL-C levels (135-159 mg/dL) yielded absolute risks equivalent to those with LDL-C ≥160 mg/dL (23.5%, 95% CI, 17.4%-31.3%; and 20.7%, 95% CI, 16.8%-25.3%, respectively). Conclusions Concomitant elevation of LDL-C ≥135 mg/dL and lipoprotein(a) ≥100 nmol/L is associated with a high absolute risk of incident cardiovascular disease. lipoprotein(a) measurement in individuals with moderate elevations in LDL-C, who do not otherwise meet criteria for statins, may identify individuals at high cardiovascular risk.

Background The ODYSSEY OUTCOMES (Alirocumab and Cardiovascular Outcomes after Acute Coronary Syndrome) trial demonstrated that alirocumab reduced major cardiovascular events. However, because of the hierarchical testing strategy used for the multiple outcomes examined, the observed reduction in all-cause mortality was labeled "nominally significant" which has clouded its interpretation. Methods and Results We re-analyzed data from ODYSSEY OUTCOMES using Bayesian methods and generated various prior probabilities by incorporating mortality data from previous similar PCSK9 (proprotein convertase subtilisin-kexin type 9) inhibitor trials. We first used data from the ODYSSEY OUTCOMES trial with a non-informative prior, then sequentially added data from ODYSSEY LONG TERM and the FOURIER trial, giving FOURIER full weight, 50% weight and 10%. The posterior probability of a mortality reduction using only the ODYSSEY OUTCOMES data was hazard ratio 0.85 (95% CI 0.74-0.99) which corresponded to a 98.4% probability of a mortality benefit. When the ODYSSEY LONG TERM data were added to the analysis, the posterior probability was hazard ratio 0.84 (95% CI 0.72-0.97) with a 99.9% probability of mortality reduction, and when the FOURIER data were added to the analysis the posterior probability was hazard ratio 0.94 (95% CI 0.85-1.04) with an 89.1% probability of a mortality reduction. When the FOURIER trial was given only 50% or 10% weight, the probability of a mortality reduction rose 95.4% and 98.7%, respectively. We estimate that the probability of >1% absolute risk reduction ranges from 8% to 24%, while the probability of >0.5% absolute risk reduction ranges from 66% to 89%. Conclusions Our analysis demonstrates a high likelihood that alirocumab confers a reduction in all-cause mortality, despite the equivocal interpretation of the data in the original ODYSSEY OUTCOMES publication.

Importance: American College of Cardiology/American Heart Association cholesterol guidelines prioritize primary prevention statin therapy based on 10-year absolute risk (AR10) of atherosclerotic cardiovascular disease (ASCVD). However, given the same AR10, patients with higher levels of low-density lipoprotein cholesterol (LDL-C) experience greater absolute risk reduction from statin therapy., Objectives: To estimate the cost-effectiveness of expanding preventive statin treatment eligibility from standard care to patients at borderline risk (AR10, 5.0%-7.4%) for ASCVD and with high levels of LDL-C and to estimate cost-effectiveness of statin treatment across ranges of age, sex, AR10, and LDL-C levels., Design, Setting, and Participants: This study evaluated 100 simulated cohorts, each including 1 million ASCVD-free survey respondents (50% men and 50% women) aged 40 years at baseline. Cohorts were created by probabilistic sampling of the 1999-2014 US National Health and Nutrition Examination Surveys from the perspective of the US health care sector. The CVD Policy Model microsimulation version projected lifetime health and cost outcomes. Probability of first-ever coronary heart disease or stroke event was estimated by analysis of 6 pooled US cohort studies and recalibrated to match contemporary event rates. Other model variables were derived from national surveys, meta-analyses, and published literature. Data were analyzed from May 15, 2018, through June 10, 2019., Exposures: Four statin treatment strategies were compared: (1) treat all patients with AR10 of at least 7.5%, diabetes, or LDL-C of at least 190 mg/dL (standard care); (2) add treatment for borderline risk and LDL-C levels of 160 to 189 mg/dL; (3) add treatment for borderline risk and LDL-C levels of 130 to 159 mg/dL; and (4) add treatment for remainder of patients with AR10 of at least 5.0%. Statin treatment was also compared with no statin treatment in age, sex, AR10, and LDL-C strata., Main Outcomes and Measures: Lifetime quality-adjusted life-years (QALYs) and costs (2019 US dollars) were projected and discounted 3.0% annually. The primary outcome was the incremental cost-effectiveness ratio., Results: In these 100 simulated cohorts, each with 1 million patients aged 40 years at baseline (50% women and 50% men), adding preventive statins to individuals with borderline AR10 and LDL-C levels of 160 to 189 mg/dL would be cost-saving; further treating borderline AR10 and LDL-C levels of 130 to 159 mg/dL would also be cost-saving; and treating all individuals with AR10 of at least 5.0% would be highly cost-effective ($33 558/QALY) and would prevent the most ASCVD events. Within age, AR10, and sex categories, individuals with higher baseline LDL-C levels gained more QALYs from statin therapy. Cost-effectiveness increased with LDL-C level and AR10., Conclusions and Relevance: In this study, lifetime statin treatment of patients in a hypothetical cohort with borderline ASCVD risk and LDL-C levels of 160 to 189 mg/dL was found to be cost-saving. Results suggest that treating all patients at borderline risk regardless of LDL-C level would likely be highly cost-effective.

Importance: A 10-year benefit-based approach to statin therapy in primary prevention includes younger individuals with higher low-density lipoprotein cholesterol (LDL-C) and prevents more cardiovascular events than a risk-based approach. However, a 10-year treatment duration likely underestimates the expected benefits of statins., Objective: To model the impact of a 30-year benefit approach to select individuals for statin therapy., Design, Setting, and Participants: This cross-sectional analysis of the National Health and Nutrition Survey (NHANES) data set included samples of the US population from the 2009-2010, 2011-2012, and 2013-2014 data collection cycles. Individuals between 40 to 60 years old who did not have atherosclerotic cardiovascular disease, diabetes, or LDL-C levels greater than 190 mg/dL and who were not taking statins were included. Data analysis took place from November 2017 to August 2018., Exposures: We calculated 10-year risk of atherosclerotic cardiovascular disease and 10-year and 30-year absolute risk reduction (10-year ARR and 30-year ARR) of atherosclerotic cardiovascular disease for each individual., Main Outcomes and Measures: Number of individuals meeting eligibility for statins based on 10-year (atherosclerotic) cardiovascular disease risk, 10-year ARR, or 30-year ARR., Results: A total of 1688 individuals were included, representing 56.6 million US individuals. Statin eligibility based on 7.5% CVR10 was 9.5%; based on 2.3% 10-year ARR, 13.0%, and based on 15% 30-year ARR, 17.5%. The 10-year risk, 10-year benefit, and 30-year benefit approaches all led to similar acceptable mean absolute risk reductions at 30 years, with the benefit-based approaches better able to avoid treatment of individuals with low expected benefit. Individuals who met statin eligibility based solely on the 30-year ARR threshold of 15% or greater were younger (mean age, 50 [95% CI, 48-52] years) and more likely to be women (43% [95% CI, 26%-59%]) than those recommended with a 10-year ARR threshold of 2.3% or greater (mean age, 56 [95% CI, 54-57] years; 22% [95% CI, 10%-34%] women). This group also had lower 10-year risk (mean risk, 4.7% [95% CI, 4.4%-5.1%]) and higher LDL-C levels (mean level, 149 mg/dL [95% CI, 142-155 mg/dL]) than those recommended with a 10-year ARR threshold of 2.3% or greater (mean risk, 9.3% [95% CI, 8.3%-10.2%]; mean LDL-C levels, 110 [103-118] mg/dL). Preventable atherosclerotic cardiovascular disease events in 10 and 30 years were highest using the 30-year benefit approach (296 000 at 10 years and 2.03 million at 30 years) and lowest based on 10-year risk (204 000 at 10 years and 1.18 million at 30 years)., Conclusions and Relevance: A long-term benefit approach to statin eligibility identifies nearly 1 in 6 individuals as having a high degree of expected long-term benefit of statins, with a number needed to treat of less than 7. This approach identifies younger individuals with higher LDL-C levels who would not be currently recommended for treatment and may provide a more optimal approach for determining statin eligibility in primary prevention.

Objective: To reanalyze data from recent randomized trials of statins to assess whether the benefits and risks of statins are mediated primarily via their LDL-C (low-density lipoprotein cholesterol) lowering effects or via other mechanisms., Approach and Results: We adapted Egger regression, a technique frequently used in Mendelian randomization studies to detect genetic pleiotropy, to reanalyze the available randomized control trial data of statin therapy. For cardiovascular end points, each 1 mmol/L change in LDL-C with statin therapy was associated with a hazard ratio of 0.77 (95% confidence interval, 0.71-0.84) with an intercept that was indistinguishable from zero (intercept, -0.0032; [95% confidence interval, -0.090 to 0.084]; P =0.94), indicating no pleiotropy. For incident diabetes mellitus, a 1 mmol/L change in LDL-C with statin therapy was associated with a hazard ratio of 1.07 (95% confidence interval, 0.99-1.16) and an intercept nondistinguishable from zero (intercept, -0.015; [95% confidence interval, -0.30 to 0.27]; P =0.91), again indicating no pleiotropy., Conclusions: Our reanalysis of the randomized control trial data using Egger regression adds to the existing evidence that the cardiovascular benefits of statins and their association with incident diabetes mellitus are mediated primarily, if not entirely, via their LDL-C lowering properties rather than by any pleiotropic effects., (© 2017 American Heart Association, Inc.)

Background: Higher concentrations of the apolipoprotein B (apoB) lipoproteins increase the risk of cardiovascular disease. However, whether the risk associated with apoB lipoproteins varies with age has not been well examined., Methods and Results: We determined the associations for total cholesterol, low-density lipoprotein (LDL)-cholesterol (LDL-C), non-high-density lipoprotein-cholesterol (non-HDL-C), apoB, apolipoprotein A-I (apoA-I), and HDL-cholesterol (HDL-C) with myocardial infarction at different ages in 11 760 controls and 8998 myocardial infarction cases of the INTERHEART Study. Logistic regression was used to compute the odds ratio of myocardial infarction for 1 SD change in each lipid marker by decade from <40 to >70 years of age. Except for those >70, plasma levels of total cholesterol, LDL-C, and non-HDL-C and apoB were greater in cases than controls. However, the average levels of these markers decreased significantly as age increased. By contrast, levels of apoA-I and HDL-C were significantly greater in controls than cases but increased significantly as age increased. The cardiovascular risk associated with the atherogenic lipid markers differed at different ages. Most notably, there was a significant decline in the odds ratio for total cholesterol, LDL-C, and non-HDL-C, and apoB with increases in age whereas the odds ratios associated with apoA-I and HDL-C were consistent across the age groups., Conclusions: These data indicate that the risk of cardiovascular events associated with apoB particles is greater in younger compared to older individuals. This finding is consistent with greater relative benefit from LDL-lowering therapy in younger compared to older individuals and so argues for therapy in younger individuals with elevated lipids., (© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Background: The National Lipid Association (NLA) selected non-HDL-C as its prime index of the cardiovascular risk associated with the apoB lipoproteins. ApoB was recommended only as an optional secondary target after low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (HDL-C) targets were achieved., Objective: The aims of this analysis were to determine whether (1) all relevant uses of apoB were considered by the NLA; (2) all the relevant evidence was considered by the NLA panel; and (3) all the evidence that was considered was interpreted correctly., Results: (1) The utility of apoB in the diagnosis of the atherogenic dyslipoproteinemias was not considered. (2) All the relevant observational studies were not identified, and some that were cited were incorrectly interpreted. In particular, an equal hazard ratio for two markers in a group does not mean they will predict risk equally in individuals within the group in whom they are discordant. This matters because discordance analysis consistently demonstrates apoB and LDL particle number are more accurate measures of cardiovascular risk than LDL-C/non-HDL-C. (3) The target levels of apoB selected by the NLA are too high relative to the levels selected for LDL-C and non-HDL-C., Conclusions: The review of the evidence by the NLA was incomplete. More complete examination of the evidence indicates that apoB is a more accurate marker of cardiovascular risk than non-HDL-C and that the practice of lipidology would be improved by inclusion of apoB along with lipoprotein lipids in routine clinical care., (Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.)

Background: Current recommendations for lipoprotein(a) (Lp[a]) focus on the control of other risk factors, including lowering low-density lipoprotein cholesterol (LDL-C), with little evidence to support this approach. Identifying interactions between Lp(a) and other risk factors could identify individuals at increased risk for Lp(a)-mediated disease., Methods and Results: We used a case-only study design and included 939 participants (median age=49 years, interquartile range 46-53, women=33.1%) from the GENdEr and Sex determInantS of cardiovascular disease: from bench to beyond-Premature Acute Coronary Syndrome (GENESIS-PRAXY) study, a multicenter prospective cohort study of premature acute coronary syndrome. There was a higher prevalence of elevated Lp(a) levels (>50 mg/dL; 80th percentile) in PRAXY participants as compared to the general population (31% versus 20%; P<0.001). Lp(a) was strongly associated with LDL-C (adjusted β 0.17; P<0.001). Individuals with high Lp(a) were more likely to have LDL-C >2.5 mmol/L, indicating a synergistic interaction (adjusted odds ratio 1.51; 95% CI 1.08-2.09; P=0.015). The interaction with high Lp(a) was stronger at increasing LDL-C levels (LDL-C >3.5, adjusted odds ratio 1.87; LDL-C >4.5, adjusted odds ratio 2.72). In a polytomous logistic model comparing mutually exclusive LDL-C categories, the interaction with high Lp(a) became attenuated at LDL-C ≤3.5 mmol/L (odds ratio 1.16; 95% CI 0.80-1.68, P=0.447). Other risk factors were not associated with high Lp(a)., Conclusions: In young acute coronary syndrome patients, high Lp(a) is more prevalent than in the general population and is strongly associated with high LDL-C, suggesting that Lp(a) confers greater risk for acute coronary syndrome when LDL-C is elevated. Individuals with high Lp(a) and LDL-C >3.5 mmol/L may warrant aggressive LDL-C lowering., (© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Aims: Analyses using conventional statistical methodologies have yielded conflicting results as to whether low-density lipoprotein cholesterol (LDL-C) or non-high-density lipoprotein cholesterol (non-HDL-C) or apolipoprotein B (apoB) is the best marker of the apoB-associated risk of coronary heart disease. The aim of this study was to determine the additional value of apoB beyond LDL-C or non-HDL-C as a predictor of coronary heart disease., Methods and Results: For each patient from the Framingham Offspring Cohort aged 40-75 years (n = 2966), we calculated the extent to which the observed apoB differed from the expected apoB based on their LDL-C or non-HDL-C. We added this difference to a Cox model predicting new onset coronary heart disease over a maximum of 20 years adjusting for standard risk factors plus LDL-C or non-HDL. The difference between observed and expected apoB over LDL-C or non-HDL-C was highly prognostic of future coronary heart disease events: adjusted hazard ratios 1.26 (95% confidence interval: 1.15, 1.37) and 1.20 (1.11, 1.29), respectively, for each standard deviation increase beyond expected apoB levels. When this difference between observed and expected apoB was added to standard coronary heart disease prediction models including LDL-C or non-HDL-C, prediction improved significantly (likelihood ratio test p-values <0.0001) and discrimination c-statistics increased from 0.72 to 0.73. The corresponding relative integrated discrimination improvements were 11% and 8%, respectively., Conclusions: apoB improves risk assessment of future coronary heart disease events over and beyond LDL-C or non-HDL-C, which is consistent with coronary risk being more closely related to the number of atherogenic apoB particles than to the mass of cholesterol within them., (© The European Society of Cardiology 2015.)

Importance: Plasma low-density lipoprotein cholesterol (LDL-C) has been associated with aortic stenosis in observational studies; however, randomized trials with cholesterol-lowering therapies in individuals with established valve disease have failed to demonstrate reduced disease progression., Objective: To evaluate whether genetic data are consistent with an association between LDL-C, high-density lipoprotein cholesterol (HDL-C), or triglycerides (TG) and aortic valve disease., Design, Setting, and Participants: Using a Mendelian randomization study design, we evaluated whether weighted genetic risk scores (GRSs), a measure of the genetic predisposition to elevations in plasma lipids, constructed using single-nucleotide polymorphisms identified in genome-wide association studies for plasma lipids, were associated with aortic valve disease. We included community-based cohorts participating in the CHARGE consortium (n = 6942), including the Framingham Heart Study (cohort inception to last follow-up: 1971-2013; n = 1295), Multi-Ethnic Study of Atherosclerosis (2000-2012; n = 2527), Age Gene/Environment Study-Reykjavik (2000-2012; n = 3120), and the Malmö Diet and Cancer Study (MDCS, 1991-2010; n = 28,461)., Main Outcomes and Measures: Aortic valve calcium quantified by computed tomography in CHARGE and incident aortic stenosis in the MDCS., Results: The prevalence of aortic valve calcium across the 3 CHARGE cohorts was 32% (n = 2245). In the MDCS, over a median follow-up time of 16.1 years, aortic stenosis developed in 17 per 1000 participants (n = 473) and aortic valve replacement for aortic stenosis occurred in 7 per 1000 (n = 205). Plasma LDL-C, but not HDL-C or TG, was significantly associated with incident aortic stenosis (hazard ratio [HR] per mmol/L, 1.28; 95% CI, 1.04-1.57; P = .02; aortic stenosis incidence: 1.3% and 2.4% in lowest and highest LDL-C quartiles, respectively). The LDL-C GRS, but not HDL-C or TG GRS, was significantly associated with presence of aortic valve calcium in CHARGE (odds ratio [OR] per GRS increment, 1.38; 95% CI, 1.09-1.74; P = .007) and with incident aortic stenosis in MDCS (HR per GRS increment, 2.78; 95% CI, 1.22-6.37; P = .02; aortic stenosis incidence: 1.9% and 2.6% in lowest and highest GRS quartiles, respectively). In sensitivity analyses excluding variants weakly associated with HDL-C or TG, the LDL-C GRS remained associated with aortic valve calcium (P = .03) and aortic stenosis (P = .009). In instrumental variable analysis, LDL-C was associated with an increase in the risk of incident aortic stenosis (HR per mmol/L, 1.51; 95% CI, 1.07-2.14; P = .02)., Conclusions and Relevance: Genetic predisposition to elevated LDL-C was associated with presence of aortic valve calcium and incidence of aortic stenosis, providing evidence supportive of a causal association between LDL-C and aortic valve disease. Whether earlier intervention to reduce LDL-C could prevent aortic valve disease merits further investigation.

All current guidelines use the 10-year risk of a cardiovascular event to select subjects for statin primary preventive therapy. Benefit from therapy is stated to be determined by risk with the result that statin primary preventive therapy is initiated only when the risk of a cardiovascular event over the next decade exceeds a specified level. Thus all current guidelines are based primarily on the Risk-Benefit paradigm of primary prevention. The recent American Heart Association/American College of Cardiology guidelines differ from others in basing selection for statin therapy virtually exclusively on risk except for those few subjects with markedly elevated levels of low-density lipoprotein cholesterol (LDL-C). The Causal Exposure paradigm differs from the Risk-Benefit paradigm in that the objective of therapy is to prevent the anatomic disease within arterial walls that produces cardiovascular risk. Moreover, the anatomic disease and, therefore, the cardiovascular risk, is a function of the injurious action of the causal factors of vascular disease, such as blood pressure and LDL, on the arterial wall over long periods. In this article, we explain the strengths and weaknesses of both paradigms to provide a more secure framework to compare the strengths and weaknesses in the different cholesterol guidelines with particular emphasis on the evidence that the cardiovascular risk and the benefit from statin therapy is related to the level of LDL., (Copyright © 2014 National Lipid Association. Published by Elsevier Inc. All rights reserved.)