S. Matthijs Boekholdt

Association of LDL Cholesterol, Non–HDL Cholesterol, and Apolipoprotein B Levels With Risk of Cardiovascular Events Among Patients Treated With Statins: A Meta-analysis

CONTEXTnThe associations of low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), and apolipoprotein B (apoB) levels with the risk of cardiovascular events among patients treated with statin therapy have not been reliably documented.nnnOBJECTIVEnTo evaluate the relative strength of the associations of LDL-C, non-HDL-C, and apoB with cardiovascular risk among patients treated with statin therapy.nnnDESIGNnMeta-analysis of individual patient data from randomized controlled statin trials in which conventional lipids and apolipoproteins were determined in all study participants at baseline and at 1-year follow-up.nnnDATA SOURCESnRelevant trials were identified by a literature search updated through December 31, 2011. Investigators were contacted and individual patient data were requested and obtained for 62,154 patients enrolled in 8 trials published between 1994 and 2008.nnnDATA EXTRACTIONnHazard ratios (HRs) and corresponding 95% CIs for risk of major cardiovascular events adjusted for established risk factors by 1-SD increase in LDL-C, non-HDL-C, and apoB.nnnRESULTSnAmong 38,153 patients allocated to statin therapy, 158 fatal myocardial infarctions, 1678 nonfatal myocardial infarctions, 615 fatal events from other coronary artery disease, 2806 hospitalizations for unstable angina, and 1029 fatal or nonfatal strokes occurred during follow-up. The adjusted HRs for major cardiovascular events per 1-SD increase were 1.13 (95% CI, 1.10-1.17) for LDL-C, 1.16 (95% CI, 1.12-1.19) for non-HDL-C, and 1.14 (95% CI, 1.11-1.18) for apoB. These HRs were significantly higher for non-HDL-C than LDL-C (P = .002) and apoB (P = .02). There was no significant difference between apoB and LDL-C (P = .21).nnnCONCLUSIONnAmong statin-treated patients, on-treatment levels of LDL-C, non-HDL-C, and apoB were each associated with risk of future major cardiovascular events, but the strength of this association was greater for non-HDL-C than for LDL-C and apoB.

Lipids, Apolipoproteins, and Their Ratios in Relation to Cardiovascular Events With Statin Treatment

Background— Low-density lipoprotein (LDL) cholesterol is the principal target of lipid-lowering therapy, but recent evidence has suggested more appropriate targets. We compared the relationships of on-treatment levels of LDL cholesterol, non–high-density lipoprotein (HDL) cholesterol, and apolipoprotein B, as well as ratios of total/HDL cholesterol, LDL/HDL cholesterol, and apolipoprotein B/A-I, with the occurrence of cardiovascular events in patients receiving statin therapy. Methods and Results— A post hoc analysis was performed that combined data from 2 prospective, randomized clinical trials in which 10 001 (“Treating to New Targets”) and 8888 (“Incremental Decrease in End Points through Aggressive Lipid Lowering”) patients with established coronary heart disease were assigned to usual-dose or high-dose statin treatment. In models with LDL cholesterol, non-HDL cholesterol and apolipoprotein B were positively associated with cardiovascular outcome, whereas a positive relationship with LDL cholesterol was lost. In a model that contained non-HDL cholesterol and apolipoprotein B, neither was significant owing to collinearity. Total/HDL cholesterol ratio and the apolipoprotein B/A-I ratio in particular were each more closely associated with outcome than any of the individual proatherogenic lipoprotein parameters. Conclusions— In patients receiving statin therapy, on-treatment levels of non-HDL cholesterol and apolipoprotein B were more closely associated with cardiovascular outcome than levels of LDL cholesterol. Inclusion of measurements of the antiatherogenic lipoprotein fraction further strengthened the relationships. These data support the use of non-HDL cholesterol or apolipoprotein B as novel treatment targets for statin therapy. Given the absence of interventions that have been proven to consistently reduce cardiovascular disease risk through raising plasma levels of HDL cholesterol or apolipoprotein A-I, it seems premature to consider the ratio variables as clinically useful.

Ability of recombinant factor VIIa to reverse the anticoagulant effect of the pentasaccharide fondaparinux in healthy volunteers.

Background—The novel anticoagulant fondaparinux proved to be effective and safe in the postoperative prevention of venous thrombosis. Current phase III trials with this synthetic selective factor Xa inhibitor focus on its use in the treatment of patients with venous and arterial thrombosis. As with any anticoagulant therapy, there is a risk of bleeding complications; hence, a strategy to reverse the effects of fondaparinux is desirable. The aim of this study was to investigate whether recombinant factor VIIa (rFVIIa) could neutralize the anticoagulant effects of subcutaneously administered fondaparinux. Methods and Results—In a randomized, placebo-controlled design, 16 healthy male subjects received either a single subcutaneous dose of fondaparinux (10 mg) and a single intravenous bolus of rFVIIa (90 &mgr;g/kg; n=8), fondaparinux and placebo (n=4), or placebo and rFVIIa (n=4). Fondaparinux (or placebo) was administered 2 hours before rFVIIa (or placebo). Injection of rFVIIa after fondaparinux normalized the prolonged activated partial thromboplastin and prothrombin times and reversed the decrease in prothrombin activation fragments 1+2 (F1+2), as observed with fondaparinux alone. Thrombin-generation time and endogenous thrombin potential, which were inhibited by fondaparinux, normalized up to 6 hours after rFVIIa injection. Conclusions—rFVIIa is capable of normalizing coagulation times and thrombin generation during fondaparinux treatment. The duration of this effect ranged from 2 to 6 hours after rFVIIa injection. These results suggest that rFVIIa may be useful to reverse the anticoagulant effect of fondaparinux in case of serious bleeding complications or need for acute surgery during treatment with fondaparinux.

High-Density Lipoprotein Cholesterol, High-Density Lipoprotein Particle Size, and Apolipoprotein A-I: Significance for Cardiovascular Risk: The IDEAL and EPIC-Norfolk Studies

OBJECTIVESnThis study was designed to assess the relationship of high-density-lipoprotein cholesterol (HDL-C), HDL particle size, and apolipoprotein A-I (apoA-I) with the occurrence of coronary artery disease (CAD), with a focus on the effect of very high values of these parameters.nnnBACKGROUNDnHigh plasma levels of HDL-C and apoA-I are inversely related to the risk of CAD. However, recent data suggest that this relationship does not hold true for very high HDL-C levels, particularly when a preponderance of large HDL particles is observed.nnnMETHODSnWe conducted a post-hoc analysis of 2 prospective studies: the IDEAL (Incremental Decrease in End Points through Aggressive Lipid Lowering; n = 8,888) trial comparing the efficacy of high-dose to usual-dose statin treatment for the secondary prevention of cardiovascular events, and the EPIC (European Prospective Investigation into Cancer and Nutrition)-Norfolk case-control study, including apparently healthy individuals who did (cases, n = 858) or did not (control patients, n = 1,491) develop CAD during follow-up. In IDEAL, only HDL-C and apoA-I were available; in EPIC-Norfolk, nuclear magnetic resonance spectroscopy-determined HDL particle sizes were also available.nnnRESULTSnIn the IDEAL study, higher HDL-C proved a significant major cardiac event risk factor following adjustment for age, gender, smoking, apoA-I, and apoB. A similar association was observed for HDL particle size in EPIC-Norfolk. Increased risk estimates were particularly present in the high ends of the distributions. In contrast, apoA-I remained negatively associated across the major part of its distribution in both studies.nnnCONCLUSIONSnWhen apoA-I and apoB are kept constant, HDL-C and HDL particle size may confer risk at very high values. This does not hold true for very high levels of apoA-I at fixed levels of HDL-C and apoB. These findings may have important consequences for assessment and treatment of CAD risk.

Genetic Variants Influencing Circulating Lipid Levels and Risk of Coronary Artery Disease

Objective—Genetic studies might provide new insights into the biological mechanisms underlying lipid metabolism and risk of CAD. We therefore conducted a genome-wide association study to identify novel genetic determinants of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides. Methods and Results—We combined genome-wide association data from 8 studies, comprising up to 17 723 participants with information on circulating lipid concentrations. We did independent replication studies in up to 37 774 participants from 8 populations and also in a population of Indian Asian descent. We also assessed the association between single-nucleotide polymorphisms (SNPs) at lipid loci and risk of CAD in up to 9 633 cases and 38 684 controls. We identified 4 novel genetic loci that showed reproducible associations with lipids (probability values, 1.6×10−8 to 3.1×10−10). These include a potentially functional SNP in the SLC39A8 gene for HDL-C, an SNP near the MYLIP/GMPR and PPP1R3B genes for LDL-C, and at the AFF1 gene for triglycerides. SNPs showing strong statistical association with 1 or more lipid traits at the CELSR2, APOB, APOE-C1-C4-C2 cluster, LPL, ZNF259-APOA5-A4-C3-A1 cluster and TRIB1 loci were also associated with CAD risk (probability values, 1.1×10−3 to 1.2×10−9). Conclusion—We have identified 4 novel loci associated with circulating lipids. We also show that in addition to those that are largely associated with LDL-C, genetic loci mainly associated with circulating triglycerides and HDL-C are also associated with risk of CAD. These findings potentially provide new insights into the biological mechanisms underlying lipid metabolism and CAD risk.

Very low levels of atherogenic lipoproteins and the risk for cardiovascular events: a meta-analysis of statin trials.

BACKGROUNDnLevels of atherogenic lipoproteins achieved with statin therapy are highly variable, but the consequence of this variability for cardiovascular disease risk is not well-documented.nnnOBJECTIVESnThe aim of this meta-analysis was to evaluate: 1) the interindividual variability of reductions in low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), or apolipoprotein B (apoB) levels achieved with statin therapy; 2) the proportion of patients not reaching guideline-recommended lipid levels on high-dose statin therapy; and 3) the association between very low levels of atherogenic lipoproteins achieved with statin therapy and cardiovascular disease risk.nnnMETHODSnThis meta-analysis used individual patient data from 8 randomized controlled statin trials, in which conventional lipids and apolipoproteins were determined in all study participants at baseline and at 1-year follow-up.nnnRESULTSnAmong 38,153 patients allocated to statin therapy, a total of 6,286 major cardiovascular events occurred in 5,387 study participants during follow-up. There was large interindividual variability in the reductions of LDL-C, non-HDL-C, and apoB achieved with a fixed statin dose. More than 40% of trial participants assigned to high-dose statin therapy did not reach an LDL-C target <70 mg/dl. Compared with patients who achieved an LDL-C >175 mg/dl, those who reached an LDL-C 75 to <100 mg/dl, 50 to <75 mg/dl, and <50 mg/dl had adjusted hazard ratios for major cardiovascular events of 0.56 (95% confidence interval [CI]: 0.46 to 0.67), 0.51 (95% CI: 0.42 to 0.62), and 0.44 (95% CI: 0.35 to 0.55), respectively. Similar associations were observed for non-HDL-C and apoB.nnnCONCLUSIONSnThe reductions of LDL-C, non-HDL-C, and apoB levels achieved with statin therapy displayed large interindividual variation. Among trial participants treated with high-dose statin therapy, >40% did not reach an LDL-C target <70 mg/dl. Patients who achieve very low LDL-C levels have a lower risk for major cardiovascular events than do those achieving moderately low levels.

HDL cholesterol and residual risk of first cardiovascular events after treatment with potent statin therapy: an analysis from the JUPITER trial

BACKGROUNDnHDL-cholesterol concentrations are inversely associated with occurrence of cardiovascular events. We addressed, using the JUPITER trial cohort, whether this association remains when LDL-cholesterol concentrations are reduced to the very low ranges with high-dose statin treatment.nnnMETHODSnParticipants in the randomised placebo-controlled JUPITER trial were adults without diabetes or previous cardiovascular disease, and had baseline concentrations of LDL cholesterol of less than 3.37 mmol/L and high-sensitivity C-reactive protein of 2 mg/L or more. Participants were randomly allocated by a computer-generated sequence to receive rosuvastatin 20 mg per day or placebo, with participants and adjudicators masked to treatment assignment. In the present analysis, we divided the participants into quartiles of HDL-cholesterol or apolipoprotein A1 and sought evidence of association between these quartiles and the JUPITER primary endpoint of first non-fatal myocardial infarction or stroke, hospitalisation for unstable angina, arterial revascularisation, or cardiovascular death. This trial is registered with ClinicalTrials.gov, number NCT00239681.nnnFINDINGSnFor 17,802 patients in the JUPITER trial, rosuvastatin 20 mg per day reduced the incidence of the primary endpoint by 44% (p<0.0001). In 8901 (50%) patients given placebo (who had a median on-treatment LDL-cholesterol concentration of 2.80 mmol/L [IQR 2.43-3.24]), HDL-cholesterol concentrations were inversely related to vascular risk both at baseline (top quartile vs bottom quartile hazard ratio [HR] 0.54, 95% CI 0.35-0.83, p=0.0039) and on-treatment (0.55, 0.35-0.87, p=0.0047). By contrast, among the 8900 (50%) patients given rosuvastatin 20 mg (who had a median on-treatment LDL-cholesterol concentration of 1.42 mmol/L [IQR 1.14-1.86]), no significant relationships were noted between quartiles of HDL-cholesterol concentration and vascular risk either at baseline (1.12, 0.62-2.03, p=0.82) or on-treatment (1.03, 0.57-1.87, p=0.97). Our analyses for apolipoprotein A1 showed an equivalent strong relation to frequency of primary outcomes in the placebo group but little association in the rosuvastatin group.nnnINTERPRETATIONnAlthough measurement of HDL-cholesterol concentration is useful as part of initial cardiovascular risk assessment, HDL-cholesterol concentrations are not predictive of residual vascular risk among patients treated with potent statin therapy who attain very low concentrations of LDL cholesterol.nnnFUNDINGnAstraZeneca.

Lipid parameters for measuring risk of cardiovascular disease

Besides measuring blood pressure and glucose levels, assessing the lipid spectrum is the method most commonly used to identify individuals at high risk of cardiovascular disease (CVD), as well as those who are likely to benefit most from lipid-lowering therapy. Although lowering LDL-cholesterol levels is the primary target of therapy in most clinical guidelines, accumulating evidence indicates that other lipoprotein–lipid measurements could provide a predictive value over and above that of LDL-cholesterol levels. For example, individuals treated with statins who achieve low LDL-cholesterol levels, but have high concentrations of either non-HDL cholesterol or apolipoprotein (apo) B, remain at increased cardiovascular risk. Similarly, individuals with low levels of either HDL cholesterol or apo A-I are also likely to experience cardiovascular events, despite having normal LDL-cholesterol levels. The residual cardiovascular risk, beyond that characterized by LDL-cholesterol levels alone, is exacerbated by physical inactivity and abdominal obesity, which are both increasingly prevalent risk factors for CVD. In this Review, we discuss the measurement of various lipoprotein–lipid parameters for the prediction of CVD risk, and their importance in identifying those patients who are likely to benefit from lipid-lowering therapy. The impact of recent studies on clinical guidelines is also considered.

Cardiovascular Event Reduction Versus New-Onset Diabetes During Atorvastatin Therapy: Effect of Baseline Risk Factors for Diabetes

OBJECTIVESnThe purpose of this study was to compare the incidence of new-onset diabetes (NOD) with cardiovascular (CV) event reduction at different levels of NOD risk.nnnBACKGROUNDnStatins reduce the number of CV events but increase the incidence of NOD. We previously reported that 4 factors independently predicted NOD: fasting blood glucose >100 mg/dl, fasting triglycerides >150 mg/dl, body mass index >30 kg/m(2), and history of hypertension.nnnMETHODSnWe compared NOD incidence with CV event reduction among 15,056 patients with coronary disease but without diabetes at baseline in the TNT (Treating to New Targets) (n = 7,595) and IDEAL (Incremental Decrease in Endpoints Through Aggressive Lipid Lowering) (n = 7,461) trials. CV events included coronary heart disease death, myocardial infarction, stroke, and resuscitated cardiac arrest.nnnRESULTSnAmong 8,825 patients with 0 to 1 of the aforementioned NOD risk factors at baseline, NOD developed in 142 of 4,407 patients in the atorvastatin 80 mg group and in 148 of 4,418 in the atorvastatin 10 mg and simvastatin 20 to 40 mg groups (3.22% vs. 3.35%; hazard ratio [HR]: 0.97; 95% confidence intervals [CI]: 0.77 to 1.22). Among the remaining 6,231 patients with 2 to 4 NOD risk factors, NOD developed in 448 of 3,128 in the atorvastatin 80 mg group and in 368 of 3,103 in the lower-dose groups (14.3% vs. 11.9%; HR: 1.24; 95% CI: 1.08 to 1.42; p = 0.0027). The number of CV events was significantly reduced with atorvastatin 80 mg in both NOD risk groups.nnnCONCLUSIONSnCompared with lower-dose statin therapy, atorvastatin 80 mg/day did not increase the incidence of NOD in patients with 0 to 1 NOD risk factors but did, by 24%, among patients with 2 to 4 NOD risk factors. The number of CV events was significantly reduced with atorvastatin 80 mg in both NOD risk groups.

Oxidation-specific biomarkers, lipoprotein(a), and risk of fatal and nonfatal coronary events.

OBJECTIVESnThis study sought to assess whether oxidation-specific biomarkers are associated with an increased risk of coronary artery disease (CAD) events.nnnBACKGROUNDnThe relationship of a panel of oxidative biomarkers and lipoprotein(a) [Lp(a)] to CAD risk is not fully determined.nnnMETHODSnA prospective case-control study nested in the EPIC (European Prospective Investigation of Cancer)-Norfolk cohort of 45- to 79-year-old apparently healthy men and women followed for approximately 6 years was designed. Cases consisted of participants in whom fatal or nonfatal CAD developed, matched by sex, age, and enrollment time with controls without CAD. Baseline levels of oxidized phospholipids on apolipoprotein B-100 particles and Lp(a) were measured in 763 cases and 1,397 controls. Their relationship to secretory phospholipase A(2) type IIA mass and activity, myeloperoxidase mass, and lipoprotein-associated phospholipase A(2) activity and association with CAD events were determined.nnnRESULTSnAfter adjusting for age, smoking, diabetes, low- and high-density lipoprotein cholesterol, and systolic blood pressure, the highest tertiles of oxidized phospholipids on apolipoprotein B-100 particles and Lp(a) were associated with a significantly higher risk of CAD events (odds ratios: 1.67 and 1.64, respectively; p < 0.001) compared with the lowest tertiles. The odds ratio of CAD events associated with the highest tertiles of oxidized phospholipids on apolipoprotein B-100 particles or Lp(a) was significantly potentiated (approximately doubled) by the highest tertiles of secretory phospholipase A(2) activity and mass but less so for myeloperoxidase and lipoprotein-associated phospholipase A(2) activity. The odds ratios for fatal CAD were higher than for the combined end point. After taking into account the Framingham Risk Score, c-index values progressively increased when oxidative biomarkers were added to the model.nnnCONCLUSIONSnThis EPIC-Norfolk study links pathophysiologically related oxidation-specific biomarkers and Lp(a) with CAD events. Oxidation-specific biomarkers provide cumulative predictive value when added to traditional cardiovascular risk factors.