Outcomes after STEMI in old multimorbid patients with complex health needs and the effect of invasive management.

BACKGROUND: The aim of this study was to assess one-year outcomes of invasive and non-invasive strategies in ST-elevation myocardial infarction (STEMI) among multimorbid older people with complex health needs. METHODS: We included patients, registered between 2006 and 2013 in the SWEDEHEART registry, who were 70 years old or older with STEMI, had multimorbidity and complex health needs and were discharged alive. The one-year outcomes of patients who underwent invasive strategy (examined with coronary angiography ≤14 days) were compared to those who did not. The primary event was a composite of all-cause death, admission due to new acute coronary syndrome, stroke or transient ischemic attack. RESULTS: We identified patients, and 1089 were managed invasively and 570 non-invasively. The mean age was 79 years and 83 years in the 2 groups, respectively. After multivariable adjustment for baseline differences between the groups, including propensity scores, the primary event occurred in 31% of patients in the invasive group and 55% in the non-invasive group, adjusted hazard ratio (95% confidence intervals): 0.67 (0.54-0.83). One-year mortality was 18% in the invasive group and 45% in the non-invasive group, adjusted hazard ratio 0.51 (0.39-0.65). CONCLUSIONS: Multimorbid older people with complex health needs and STEMI had high rates of new ischemic events and death. In this cohort of older, high risk STEMI patients, an invasive strategy was associated with lower event rates. Randomized studies are needed to clarify whether these high risk patients who might benefit from invasive care are being managed too conservatively.

Genome-wide association and Mendelian randomization study of NT-proBNP in patients with acute coronary syndrome.

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a strong predictor of mortality in coronary artery disease and is widely employed as a prognostic biomarker. However, a causal relationship between NT-proBNP and clinical endpoints has not been established. We have performed a genome-wide association and Mendelian randomization study of NT-proBNP. We used a discovery set of 3740 patients from the PLATelet inhibition and patient Outcomes (PLATO) trial, which enrolled 18 624 patients with acute coronary syndrome (ACS). A further set of 5492 patients, from the same trial, was used for replication. Genetic variants at two novel loci (SLC39A8 and POC1B/GALNT4) were associated with NT-proBNP levels and replicated together with the previously known NPPB locus. The most significant SNP (rs198389, pooled P = 1.07 × 10(-15)) in NPPB interrupts an E-box consensus motif in the gene promoter. The association in SLC39A8 is driven by a deleterious variant (rs13107325, pooled P = 5.99 × 10(-10)), whereas the most significant SNP in POC1B/GALNT4 (rs11105306, pooled P = 1.02 × 10(-16)) is intronic. The SLC39A8 SNP was associated with higher risk of cardiovascular (CV) death (HR = 1.39, 95% CI: 1.08-1.79, P = 0.0095), but the other loci were not associated with clinical endpoints. We have identified two novel loci to be associated with NT-proBNP in patients with ACS. Only the SLC39A8 variant, but not the NPPB variant, was associated with a clinical endpoint. Due to pleotropic effects of SLC39A8, these results do not suggest that NT-proBNP levels have a direct effect on mortality in ACS patients. PLATO Clinical Trial Registration: www.clinicaltrials.gov; NCT00391872.

Long-term versus short-term dual antiplatelet therapy was similarly associated with a lower risk of death, stroke, or infarction in patients with acute coronary syndrome regardless of underlying kidney disease.

Scarce and conflicting evidence exists on whether clopidogrel is effective and whether dual antiplatelet treatment (DAPT) is safe in patients with acute coronary syndrome and chronic kidney disease (CKD). To study this, we performed an observational, prospective, multicenter cohort study of 36,001 patients of the SWEDEHEART registry. The exposure was DAPT prolonged after 3 months versus DAPT stopped at 3 months in consecutive patients with acute coronary syndrome and known serum creatinine. DAPT duration with clopidogrel and aspirin was assessed by dispensed tablets. CKD stages were classified according to estimated glomerular filtration rate (eGFR). Study outcomes were 1) the composite of death, myocardial infarction, or ischemic stroke; 2) bleeding; or 3) the aggregate of these two outcomes within day 111 and 365 from discharge. A longer DAPT duration, as compared with 3-month DAPT, was associated with lower hazard ratios for outcome one in each CKD stratum (eGFR over 60, adjusted hazard ratio [95% confidence interval] 0.76 [0.67-0.85]; eGFR 60 and less, 0.84 [0.73-0.96], of which eGFR between 45 and 60, 0.85 [0.70-1.05], eGFR between 30 and 45, 0.78 [0.62-0.97]; eGFR 30 and less ml/min/1.73 m2, 0.93 [0.70-1.24]. Bleeding (outcome 2) was in general more common in the longer DAPT group of each aforementioned CKD stratum. Aggregated outcome analysis (outcome 3) similarly favored longer DAPT in each stratum. There was no interaction between DAPT duration and CKD strata for any of the study outcomes. Thus, a prolonged as compared with three-month DAPT was similarly associated with a lower risk of death, stroke, or reinfarction regardless of underlying CKD.

Real-life clinical outcomes with everolimus eluting platinum chromium stent with an abluminal biodegradable polymer in patients from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR).

BACKGROUND: No previous studies have evaluated the performance of the Synergy stent in a large real-life population. OBJECTIVES: To describe the initial real-life experience with a novel everolimus eluting platinum chromium stent with abluminal biodegradable polymer (SYNERGY) in unselected patients from a nationwide registry. METHODS: All implanted Synergy stents were compared with other new generation drug eluting stents (n-DES) with >1,000 implantations in Sweden between March 2013 and October 2015. Restenosis, definite stent thrombosis (ST), myocardial infarction (MI) and death rates were assessed using propensity score and Cox regression analyses. RESULTS: A total of 7,886 of Synergy stents and 64,429 other n-DES (BioMatrix, N = 1,953; Orsiro, N = 4,946; Promus Element Plus, N= 2,543; Promus Premier, N= 20,414; Xience Xpedition, N= 7,971, Resolute/Resolute Integrity, N = 19,021; Ultimaster, N = 1,156; Resolute Onyx, N = 6,425) were implanted in 42,357 procedures. Restenosis and stent thrombosis occurred in 642 and 314 cases, respectively, in the overall population at 1 year. The cumulative rate of restenosis (1.1% vs. 1.0%, adjusted HR: 1.24 95% CI: 0.88-1.75; P = 0.21) and ST (0.4% vs. 0.5%, adjusted HR: 0.97; 95% CI: 0.63-1.50; P = 0.17) up to 1 year was low in both the Synergy group and the other n-DES group. Death occurred in 5.2% versus 4.5% (adjusted HR: 1.14; 95% CI: 0.96-1.36; P = 0.11) and MI in 3.2% versus 3.5%, (adjusted HR: 1.11; 95% CI: 0.93-1.33; P = 0.24) up to 1 year. CONCLUSIONS: In a large real-life population the Synergy stent appears to be safe and effective with a low rate of restenosis and ST comparable with other n-DES. © 2017 Wiley Periodicals, Inc.

Outcomes in patients treated with ticagrelor or clopidogrel after acute myocardial infarction: experiences from SWEDEHEART registry.

AIMS: Ticagrelor reduces ischaemic events and mortality in acute coronary syndrome (ACS) vs. clopidogrel. We wished to study clinical outcomes in a large real-world population post-ACS. METHODS AND RESULTS: We performed a prospective cohort study in 45 073 ACS patients enrolled into Swedish Web system for Enhancement and Development of Evidence-based care in Heart Disease Evaluated According to Recommended Therapies who were discharged on ticagrelor (N = 11 954) or clopidogrel (N = 33 119) between 1 January 2010 and 31 December 2013. The primary outcome was a composite of all-cause death, re-admission with myocardial infarction (MI) or stroke, secondary outcomes as the individual components of the primary outcome, and re-admission with bleeding. The risk of the primary outcome with ticagrelor vs. clopidogrel was 11.7 vs. 22.3% (adjusted hazard ratio (HR) 0.85 [95% confidence interval: 0.78-0.93]), risk of death 5.8 vs. 12.9% (adjusted HR 0.83 [0.75-0.92]), and risk of MI 6.1 vs. 10.8% (adjusted HR 0.89 [0.78-1.01]) at 24 months. Re-admission with bleeding with ticagrelor vs. clopidogrel occurred in 5.5 vs. 5.2% (adjusted HR 1.20 [1.04-1.40]). In a subset of patients undergoing percutaneous coronary intervention (PCI) on ticagrelor vs. clopidogrel the PCI-related in-hospital bleeding was 3.7 vs. 2.7% (adjusted odds ratio, OR, 1.57 [1.30-1.90]). CONCLUSION: Ticagrelor vs. clopidogrel post-ACS was associated with a lower risk of death, MI, or stroke, as well as death alone. Risk of bleeding was higher with ticagrelor. These real-world outcomes are consistent with randomized trial results.

Low real-world early stent thrombosis rates in ST-elevation myocardial infarction patients and the use of bivalirudin, heparin alone or glycoprotein IIb/IIIa inhibitor treatment: A nationwide Swedish registry report.

BACKGROUND: In recent studies of primary percutaneous coronary intervention (PCI), bivalirudin compared with heparin has been associated with increased risk of stent thrombosis (ST). Our aim was to describe incidence and outcome of definite, early ST in a large contemporary primary PCI population divided in antithrombotic therapy subgroups. METHODS AND RESULTS: A prospective, observational cohort study of all 31,258 ST-elevation myocardial infarction patients who received a stent in Sweden from January 2007 to July 2014 in the SWEDEHEART registry was conducted. Patients were divided into 3 groups: bivalirudin, heparin alone, or glycoprotein IIb/IIIa inhibitor treated. Primary outcome measure was incidence of definite early ST (within 30 days of PCI). Secondary outcomes included all-cause mortality. Incidence of early ST was low, regardless of bivalirudin, heparin alone, or glycoprotein IIb/IIIa inhibitor treatment (0.84%, 0.94%, and 0.83%, respectively). All-cause mortality at 1 year was 20.7% for all ST patients (n = 265), compared with 9.1% in those without ST (n = 31,286; P < .001). Patients with ST days 2-30 had numerically higher all-cause mortality at 1 year compared with patients with ST days 0-1 (23% vs 16%, P = .20). CONCLUSION: In this real-world observational study of 31,258 ST-elevation myocardial infarction patients, the incidence of early ST was low, regardless of antithrombotic treatment strategy. Early ST was associated with increased mortality. Numerically higher all-cause mortality at 1 year was noted with ST days 2-30 compared with ST days 0-1 post-PCI.

Effects of interactive patient smartphone support app on drug adherence and lifestyle changes in myocardial infarction patients: A randomized study.

BACKGROUND: Patients with myocardial infarction (MI) seldom reach recommended targets for secondary prevention. This study evaluated a smartphone application ("app") aimed at improving treatment adherence and cardiovascular lifestyle in MI patients. DESIGN: Multicenter, randomized trial. METHODS: A total of 174 ticagrelor-treated MI patients were randomized to either an interactive patient support tool (active group) or a simplified tool (control group) in addition to usual post-MI care. Primary end point was a composite nonadherence score measuring patient-registered ticagrelor adherence, defined as a combination of adherence failure events (2 missed doses registered in 7-day cycles) and treatment gaps (4 consecutive missed doses). Secondary end points included change in cardiovascular risk factors, quality of life (European Quality of Life-5 Dimensions), and patient device satisfaction (System Usability Scale). RESULTS: Patient mean age was 58 years, 81% were men, and 21% were current smokers. At 6 months, greater patient-registered drug adherence was achieved in the active vs the control group (nonadherence score: 16.6 vs 22.8 [P = .025]). Numerically, the active group was associated with higher degree of smoking cessation, increased physical activity, and change in quality of life; however, this did not reach statistical significance. Patient satisfaction was significantly higher in the active vs the control group (system usability score: 87.3 vs 78.1 [P = .001]). CONCLUSIONS: In MI patients, use of an interactive patient support tool improved patient self-reported drug adherence and may be associated with a trend toward improved cardiovascular lifestyle changes and quality of life. Use of a disease-specific interactive patient support tool may be an appreciated, simple, and promising complement to standard secondary prevention.

Effect of genetic variations on ticagrelor plasma levels and clinical outcomes.

AIMS: Ticagrelor, a direct-acting P2Y12-receptor antagonist, is rapidly absorbed and partly metabolized to the major metabolite AR-C124910XX (ARC). To identify single-nucleotide polymorphisms (SNPs) associated with pharmacokinetics of ticagrelor and clinical outcomes, we performed a genome-wide association study (GWAS) in patients treated with ticagrelor in the PLATO trial. METHODS AND RESULTS: A two-stage design was used for the GWAS with discovery (discovery phase: n = 1812) and replication cohorts (replication phase: n = 1941). The steady-state area under the curve (AUCss) values, estimated by the population pharmacokinetic (PK) models, were log transformed and analysed on a genome-wide scale using linear regression. SNPs were analysed against clinical events using Cox-regression in 4990 patients. An SNP (rs113681054) in SLCO1B1 was associated with levels of ticagrelor (P = 1.1 × 10(-6)) and ARC (P = 4.6 × 10(-13)). This SNP is in linkage disequilibrium with a functional variant (rs4149056) that results in decreased OATP1B1 transporter activity. Ticagrelor levels were also associated with two independent SNPs (rs62471956, P = 7.7 × 10(-15) and rs56324128, P = 9.7 × 10(-12)) in the CYP3A4 region. Further, ARC levels were associated with rs61361928 (P = 3.0 × 10(-14)) in UGT2B7. At all loci, the effects were small. None of the identified SNPs that affected ticagrelor PK were associated with the primary composite outcome (cardiovascular death myocardial infarction, and stroke), non-CABG-related bleeds or investigator-reported dyspnoea. CONCLUSION: In patients with ACS, ticagrelor pharmacokinetics is influenced by three genetic loci (SLCO1B1, UGT2B7, and CYP3A4). However, the modest genetic effects on ticagrelor plasma levels did not translate into any detectable effect on efficacy or safety during ticagrelor treatment. CLINICAL TRIAL REGISTRATION: NCT00391872.

Design and rationale of TROCADERO: A TRial Of Caffeine to Alleviate DyspnEa Related to ticagrelOr.

BACKGROUND: Ticagrelor treatment has the side effect of increased incidence of dyspnea. Adenosine-induced dyspnea is augmented by ticagrelor and can be alleviated with the adenosine antagonist theophylline. Caffeine is a closely related xanthine derivative. OBJECTIVES: The primary objective of the TROCADERO is to evaluate the effect of caffeine versus placebo on ticagrelor-associated dyspnea, measured by the visual analog scale area under the curve in patients with ongoing ticagrelor treatment after an acute coronary syndrome event. DESIGN: After a run-in period of 1 to 7 days of absence of caffeine intake, acute coronary syndrome patients with ticagrelor-induced dyspnea (planned inclusion 416) are randomized in a blinded fashion to either caffeine 200 mg twice daily or matching placebo with a treatment duration of 1 week. The primary efficacy end point is change in visual analog scale area under the curve for dyspnea, and the primary safety end point is occurrence of high on-treatment platelet reactivity measured by the VerifyNow P2Y12 assay. CONCLUSIONS: This trial will determine if adenosine antagonism by caffeine can alleviate ticagrelor-related dyspnea, without impairing the antiplatelet effect of ticagrelor.

Duration of dual antiplatelet treatment with clopidogrel and aspirin in patients with acute coronary syndrome.

AIMS: Dual antiplatelet treatment (DAPT) is a cornerstone in the treatment of acute coronary syndrome (ACS) but the optimal treatment duration is unclear. We aimed to evaluate the effect of DAPT duration with clopidogrel and aspirin on the recurrence of ischaemic events and bleeding in a large, unselected ACS population. METHODS AND RESULTS: We performed a prospective, observational cohort study of patients in Sweden (n = 56 440) admitted for ACS, with prescribed DAPT and hospitalized between January 2006 and July 2010. Patients were obtained from the SWEDEHEART register and data were merged with registers from the National Board of Health and Welfare. Depending on dispensed clopidogrel tablets, patients were divided into groups based on DAPT duration with clopidogrel and aspirin (3 months: 84-100 clopidogrel tablets (t); >3 months: >100 t; 6 months: 168-200 t; >6 months: >200 t). For the combined primary endpoint, defined as all-cause death, stroke, or re-infarction, only patients with an uneventful first 3-month period (no death, stroke, re-infarction, bleeding, stent thrombosis, or revascularization) were included. The incidence of the primary endpoint was 45 events per 1000 person-years in the >3 months DAPT group compared with 65 events per 1000 person-years in the 3 months DAPT group [adjusted HR 0.84, 95% CI (0.75; 0.95)]. Bleeding was more common in the >3 months treatment group (adjusted HR 1.56, 95% CI (1.18; 2.07), but the number of events was small. For >6 vs. 6 months DAPT, the adjusted HR for the combined endpoint was 0.75 with 95% CI (0.59; 0.95). CONCLUSION: In this contemporary, large real-life ACS population, DAPT for more than 3 months compared with a shorter duration was associated with a lower risk of death, stroke, or re-infarction. TRIAL REGISTRATION: Clinicaltrials.gov (NCT01623700).

Ticagrelor vs. clopidogrel in patients with non-ST-elevation acute coronary syndrome with or without revascularization: results from the PLATO trial.

AIMS: The optimal platelet inhibition strategy for ACS patients managed without revascularization is unknown. We aimed to evaluate efficacy and safety of ticagrelor vs. clopidogrel in the non-ST-elevation acute coronary syndrome (NSTE-ACS) subgroup of the PLATO trial, in the total cohort, and in the subgroups managed with and without revascularization within 10 days of randomization. METHODS AND RESULTS: We performed a retrospective analysis of the primary endpoint of cardiovascular death/myocardial infarction/stroke. Among 18 624 PLATO patients, 11 080 (59%) were categorized as NSTE-ACS at randomization. During the initial 10 days, 74% had angiography, 46% PCI, and 5% CABG. In NSTE-ACS patients, the primary endpoint was reduced with ticagrelor vs. clopidogrel [10.0 vs. 12.3%; hazard ratio (HR) 0.83; 95% confidence interval (CI) = 0.74-0.93], as was myocardial infarction (6.6 vs. 7.7%; HR 0.86; 95% CI = 0.74-0.99), cardiovascular death (3.7 vs. 4.9%; HR 0.77; 95% CI = 0.64-0.93), and all-cause death (4.3 vs. 5.8%; HR 0.76; 95% CI = 0.64-0.90). Major bleeding rate was similar between treatment groups (13.4 vs. 12.6%; HR 1.07; 95% CI = 0.95-1.19), but ticagrelor was associated with an increase in non-CABG major bleeding (4.8 vs. 3.8%; HR 1.28; 95% CI = 1.05-1.56). Within the first 10 days, 5366 (48.4%) patients were managed without revascularization. Regardless of revascularization or not, ticagrelor consistently reduced the primary outcome (HR 0.86 vs. 0.85, interaction P = 0.93), and all-cause death (HR 0.75 vs. 0.73, interaction P = 0.89) with no significant increase in overall major bleeding. CONCLUSION: In patients with NSTE-ACS, benefit of ticagrelor over clopidogrel in reducing ischaemic events and total mortality was consistent with the overall PLATO trial, independent of actually performed revascularization during the initial 10 days.

Lower mortality following pulmonary adverse events and sepsis with ticagrelor compared to clopidogrel in the PLATO study.

In the PLATelet inhibition and patient Outcomes (PLATO) study of patients with acute coronary syndromes, ticagrelor reduced mortality compared to clopidogrel but the mechanisms for this mortality reduction remain uncertain. We analysed adverse events (AEs) consistent with either pulmonary infection or sepsis, and subsequent mortality, in 18,421 PLATO patients treated with ticagrelor or clopidogrel. AEs occurring within 7 days of last dose of study medication were defined as "on-treatment". Serial measurements of blood leukocyte counts, C-reactive protein and interleukin-6 were performed. Fewer on-treatment pulmonary AEs occurred in the ticagrelor compared to the clopidogrel group (275 vs. 331 respectively; p = 0.019), with fewer deaths following these AEs (33 vs. 71; p < 0.001), particularly in those who remained on study medication three days after AE onset (10 vs. 43; p < 0.001). There were fewer deaths attributed to sepsis in the ticagrelor group (7 vs. 23; p = 0.003). Leukocyte counts were lower in the clopidogrel group during treatment (p < 0.0001 at 1, 3 and 6 months) but not at 1 month post-discontinuation. C-reactive protein increased more at discharge in the ticagrelor group (28.0 ± 38.0 vs. 26.1 ± 36.6 mg/l; p < 0.001) and interleukin-6 remained higher during the first month of treatment with ticagrelor. We conclude that the mortality risk following pulmonary AEs and sepsis in acute coronary syndrome patients appears to be lower during ticagrelor compared to clopidogrel therapy. Further work should assess whether ticagrelor and clopidogrel have differential effects on immune signalling.

Burden of disease and management of osteoarthritis and chronic low back pain: healthcare utilization and sick leave in Sweden, Norway, Finland and Denmark (BISCUITS): study design and patient characteristics of a real world data study.

OBJECTIVES: Osteoarthritis (OA) and chronic low back pain (CLBP) are common musculoskeletal disorders with substantial patient and societal burden. Nordic administrative registers offer a unique opportunity to study the impact of these conditions in the real-world setting. The Burden of Disease and Management of Osteoarthritis and Chronic Low Back Pain: Health Care Utilization and Sick Leave in Sweden, Norway, Finland and Denmark (BISCUITS) study was designed to study disease prevalence and the societal and economic burden in broad OA and CLBP populations. METHODS: Patients in Sweden, Norway, Finland and Denmark with diagnoses of OA or CLBP (low back pain record plus ≥2 pain relief prescriptions to indicate chronicity) were identified in specialty care, in primary care (Sweden and Finland) and in a quality-of-care register (Sweden). Matched controls were identified for the specialty care cohort. Longitudinal data were extracted on prevalence, treatment patterns, patient-reported outcomes, social and economic burden. RESULTS: Almost 1.4 million patients with OA and 0.4 million with CLBP were identified in specialty care, corresponding to a prevalence in the Nordic countries of 6.3 and 1.9%, respectively. The prevalence increased to 11-14% for OA and almost 6% for CLBP when adding patients identified in primary care. OA patients had a higher Elixhauser comorbidity index (0.66 vs. 0.46) and were using opioids (44.7 vs. 10.2%) or long-term nonsteroidal anti-inflammatory drug (NSAIDs) (20.9 vs. 4.5%) more than four times as often as compared to controls. The differences were even larger for CLBP patients compared to their controls (comorbidity index 0.89 vs. 0.39, opioid use 77.7 vs. 9.4%, and long-term NSAID use 37.2 vs. 4.8%). CONCLUSIONS: The BISCUITS study offers an unprecedented, longitudinal healthcare data source to quantify the real-world burden of more than 1.8 million patients with OA or CLBP across four countries. In subsequent papers we aim to explore among others additional outcomes and subgroups of patients, primarily those patients who may benefit most from better healthcare management.

Which antiplatelet agent for whom? Which patient populations benefit most from novel antiplatelet agents (ticagrelor, prasugrel)?

Antiplatelet treatment is a cornerstone for patients with acute coronary syndromes treated invasively or conservatively to reduce the risk of early and late occurring ischemic complications and to improve survival. Compared to clopidogrel, the novel antiplatelet agents prasugrel and ticagrelor provide faster and more consistent inhibition of platelet aggregation and result in substantially improved clinical outcome in patients with acute coronary syndromes but also an increased bleeding risk. Therefore, balancing the rope between safety and efficacy of treatment is crucial for optimizing outcome. An understanding of the similarities but also differences in pharmacological effect, clinical trial design, and outcome is crucial for understanding which patient populations benefit the most from novel antiplatelet treatments. This review provides recommendations for their optimal use.

Relationship between clopidogrel-induced platelet P2Y12 inhibition and stent thrombosis or myocardial infarction after percutaneous coronary intervention-a case-control study.

BACKGROUND: Insufficient platelet inhibition is a major determinant of stent thrombosis (STh), although the etiology is multifactorial. On-clopidogrel platelet reactivity was investigated in patients with previous angiographically confirmed STh, myocardial infarction (MI), and controls. METHODS: Using the Swedish Coronary Angiography and Angioplasty Registry, we identified patients with angiographically confirmed STh (n = 48) or MI (n = 30) while on dual antiplatelet therapy within 6 months of percutaneous coronary intervention (PCI) and matched control patients (n = 78). On-clopidogrel platelet reactivity was measured with VerifyNow P2Y12 and vasodilator-stimulated phosphoprotein (VASP) phosphorylation assay. RESULTS: The mean P2Y12 reaction units (PRU) was higher (246.8 ± 75.9 vs 200.0 ± 82.7, P = .001) in STh patients compared with controls. The optimal cutoff for STh was 222 PRU or higher (area under the curve 0.69, P < .0001) in a receiver operating characteristics (ROC) analysis. The cutoff level resulted in 70.2% sensitivity and 67.3% specificity. There was no significant difference in mean PRU but a higher device-reported percent inhibition (45.1 ± 23.8 vs 32.1 ± 23.2, P = .04) in patients with MI compared with controls. Results with the VASP phosphorylation assay were not related to the occurrence of STh or MI. CONCLUSIONS: STh was associated with high on-clopidogrel platelet reactivity measured with VerifyNow (cutoff level of PRU ≥222) but spontaneous MI in stented patients on clopidogrel treatment was not. There was, however, a substantial overlap in on-clopidogrel platelet reactivity between patients with and without on-treatment STh questioning the clinical use of platelet function testing to identify patients at high risk for STh.

Genetic variation of CYP2C19 affects both pharmacokinetic and pharmacodynamic responses to clopidogrel but not prasugrel in aspirin-treated patients with coronary artery disease.

AIMS: The metabolic pathways leading to the formation of prasugrel and clopidogrel active metabolites differ. We hypothesized that decreased CYP2C19 activity affects the pharmacokinetic and pharmacodynamic response to clopidogrel but not prasugrel. METHODS AND RESULTS: Ninety-eight patients with coronary artery disease (CAD) taking either clopidogrel 600 mg loading dose (LD)/75 mg maintenance dose (MD) or prasugrel 60 mg LD/10 mg MD were genotyped for variation in six CYP genes. Based on CYP genotype, patients were segregated into two groups: normal function (extensive) metabolizers (EM) and reduced function metabolizers (RM). Plasma active metabolite concentrations were measured at 30 min, 1, 2, 4, and 6 h post-LD and during the MD period on Day 2, Day 14, and Day 29 at 30 min, 1, 2, and 4 h. Vasodilator-stimulated phosphoprotein (VASP) and VerifyNow P2Y12 were measured predose, 2, and 24 +/- 4 h post-LD and predose during the MD period on Day 14 +/- 3 and Day 29 +/- 3. For clopidogrel, active metabolite exposure was significantly lower (P = 0.0015) and VASP platelet reactivity index (PRI, %) and VerifyNow P2Y(12) reaction unit (PRU) values were significantly higher (P < 0.05) in the CYP2C19 RM compared with the EM group. For prasugrel, there was no statistically significant difference in active metabolite exposure or pharmacodynamic response between CYP2C19 EM and RM. Variation in the other five genes demonstrated no statistically significant differences in pharmacokinetic or pharmacodynamic responses. CONCLUSION: Variation in the gene encoding CYP2C19 in patients with stable CAD contributes to reduced exposure to clopidogrel's active metabolite and a corresponding reduction in P2Y(12) inhibition, but has no significant influence on the response to prasugrel.