Plasma concentration of atorvastatin metabolites correlates with low-density lipoprotein cholesterol reduction in patients with coronary heart disease.

In this exploratory study from a randomized double-blinded crossover trial including 70 patients with coronary heart disease and self-perceived muscular side effects of statins, we aimed to determine the relationship between low-density lipoprotein cholesterol (LDL-C) reduction and atorvastatin metabolite plasma concentrations. All patients underwent a 7 weeks treatment period with atorvastatin 40 mg/day and a 7 weeks placebo period in random order. Nonlinear regression with a three-parameter equation explored the relationship between percentage LDL-C reduction (statin vs. placebo) and the pharmacokinetic variables. Mean LDL-C reduction was 49% (range 12% to 71%). The sum of 4-OH-atorvastatin acid and lactone correlated moderately with the LDL-C response (Spearman ρ 0.27, 95% confidence interval [CI]: 0.03 to 0.48). Accordingly, nonlinear regression showed R2 of 0.14 (95% CI: 0.03 to 0.37, R2 adjusted equaled 0.11). Even a perfect underlying correlation of 1.0 showed R2 = 0.32 by simulation, using historical intra-individual LDL-C variation (8.5%). The 90% inhibitory concentration was 2.1 nmol/L, and the 4-OH-metabolite sum exceeded this threshold in 34% of the patients. In conclusion, trough plasma concentrations of 4-OH-atorvastatin metabolites correlated moderately to the LDL-C reduction. A plateau LDL-C response was observed above a pharmacokinetic threshold, below which the response was highly variable. The usefulness of monitoring concentrations of atorvastatin metabolites to optimize the individual dosage have limitations, but its supportive potential may be pursued in relevant patient subsets to achieve adequate efficacy at the lowest possible dose. The results add knowledge to the overall understanding of the variable LDL-C response mediated by atorvastatin.

Preventable clinical and psychosocial factors predicted two out of three recurrent cardiovascular events in a coronary population.

BACKGROUND: The relative importance of lifestyle, medical and psychosocial factors on the risk of recurrent major cardiovascular (CV) events (MACE) in coronary patients' needs to be identified. The main objective of this study is to estimate the association between potentially preventable factors on MACE in an outpatient coronary population from routine clinical practice. METHODS: This prospective follow-up study of recurrent MACE, determine the predictive impact of risk factors and a wide range of relevant co-factors recorded at baseline. The baseline study included 1127 consecutive patients 2-36 months after myocardial infarction (MI) and/or revascularization procedure. The primary composite endpoint of recurrent MACE defined as CV death, hospitalization due to MI, revascularization, stroke/transitory ischemic attacks or heart failure was obtained from hospital records. Data were analysed using cox proportional hazard regression, stratified by prior coronary events before the index event. RESULTS: During a mean follow-up of 4.2 years from study inclusion (mean time from index event to end of study 5.7 years), 364 MACE occurred in 240 patients (21, 95% confidence interval: 19 to 24%), of which 39 were CV deaths. In multi-adjusted analyses, the strongest predictor of MACE was not taking statins (Relative risk [RR] 2.13), succeeded by physical inactivity (RR 1.73), peripheral artery disease (RR 1.73), chronic kidney failure (RR 1.52), former smoking (RR 1.46) and higher Hospital Anxiety and Depression Scale-Depression subscale score (RR 1.04 per unit increase). Preventable and potentially modifiable factors addressed accounted for 66% (95% confidence interval: 49 to 77%) of the risk for recurrent events. The major contributions were smoking, low physical activity, not taking statins, not participating in cardiac rehabilitation and diabetes. CONCLUSIONS: Coronary patients were at high risk of recurrent MACE. Potentially preventable clinical and psychosocial factors predicted two out of three MACE, which is why these factors should be targeted in coronary populations. TRIAL REGISTRATION: Registered at ClinicalTrials.gov: NCT02309255. Registered at December 5th, 2014, registered retrospectively.

No case of COX-1-related aspirin resistance found in 289 patients with symptoms of stable CHD remitted for coronary angiography.

OBJECTIVE: To assess the prevalence of a lacking aspirin effect on cyclooxygenase-1 (COX-1) ("aspirin resistance") in patients with symptomatic, stable coronary heart disease (CHD) using test methods directly reflecting inhibition of COX-1. MATERIAL AND METHODS: Arachidonic acid (AA)-induced platelet aggregation and plasma thromboxane B2 (TXB2) were determined twice 3 weeks apart - prior to elective coronary angiography - in 289 patients on 75 or 160 mg aspirin daily, all prompted to take aspirin before testing. Subjects who demonstrated lacking any effect of aspirin (>/=20 % AA-induced aggregation) on one or both occasions were later given a third test. Forty-two patients not taking aspirin were used as TXB2 controls. RESULTS: Eleven (3.8 %) had aggregation > or = 20 % in at least one of the two initial tests, but only two on both occasions. During the third test, all 11 patients had aggregation <20 %. The TXB2 distributions in controls and study patients differed markedly (mean 173 versus 19 pg/mL). Taking 45 pg/mL as the TXB2 cut-off level, sensitivity and specificity for detecting subjects taking aspirin were 90 % and 89 %, respectively. The area under the ROC curve was 0.96. CONCLUSION: Repeated AA-induced platelet aggregometry showed that COX-1 could be blocked by low-dose aspirin in all 289 tested patients, suggesting that aspirin resistance is rare in patients with stable CHD.

Clopidogrel increases expression of chemokines in peripheral blood mononuclear cells in patients with coronary artery disease: results of a double-blind placebo-controlled study.

BACKGROUND: Chemokines and platelet activation are both important in atherogenesis. Platelet inhibitors are widely used in coronary artery disease (CAD), and we hypothesized that the platelet inhibitor clopidogrel could modify chemokines in CAD patients. OBJECTIVES: We sought to investigate the effect of clopidogrel on the expression of chemokines and chemokine receptors in peripheral blood mononuclear cells (PBMC) in CAD patients. PATIENTS/METHODS: Thirty-seven patients with stable angina were randomized to clopidogrel (n = 18) or placebo (n = 19). PBMC, blood platelets and plasma were collected at baseline and after 7-10 days in the patients, and in 10 healthy controls. mRNA levels of chemokines and chemokine receptors in PBMC were analyzed by ribonuclease protection assays and real-time reverse transcriptase polymerase chain reaction. Platelet activation was studied by flow cytometry. RESULTS: (i) At baseline, the gene expression of the regulated on activation normally T-cell expressed and secreted (RANTES) chemokines and macrophage inflammatory peptide (MIP)-1beta in PBMC, the expression of CD62P and CD63 on platelets and the levels of platelet-derived microparticles (PMP) were elevated in angina patients comparing healthy controls; (ii) markers of platelet activation were either reduced (CD63) or unchanged (CD62P, PMP, beta-thromboglobulin) during clopidogrel therapy; (iii) in contrast, clopidogrel significantly up-regulated the gene expression of RANTES and MIP-1beta in PBMC, while no changes were found in the placebo group; (iv) a stable adenosine 5'-diphosphate metabolite attenuated the release of MIP-1beta, but not of RANTES, from activated PBMC in vitro. CONCLUSIONS: Even if we do not argue against a beneficial role for clopidogrel in CAD, our findings may suggest potential inflammatory effects of clopidogrel in CAD.