Faculty Bibliography

Aspirin's clinical efficacy may be influenced by body weight and mass. Although inadequate platelet inhibition by aspirin is suggested as responsible, evidence for this in non-diabetic patients is sparse. We investigated the influence of body weight and mass on aspirin's inhibition of platelet aggregation in healthy adults without diabetes. Cohort one (NYU, n = 84) had light transmission aggregometry (LTA) of platelet-rich plasma to submaximal adenosine diphosphate (ADP) and arachidonic acid (AA) before and following 1 week of daily 81 mg non-enteric coated aspirin. Subjects in the validation cohort (Duke, n = 66) were randomized to 81 mg or 325 mg non-enteric coated aspirin for 4 weeks, immediately followed by 4 weeks of the other dose, with LTA to submaximal collagen, ADP, and AA before and after each dosage period. Body mass index (BMI) range was 18.0-57.5 kg/m² and 25% were obese. Inhibition of platelet aggregation was similar irrespective of BMI, body weight and aspirin dose. There was no correlation between platelet aggregation before or after aspirin with BMI or body weight. Our data demonstrate that aspirin produces potent inhibition of direct and indirect COX1-mediated platelet aggregation in healthy adults without diabetes regardless of body weight or mass - suggesting that other mechanisms explain lower preventive efficacy of low-dose aspirin with increasing body weight/mass.

OBJECTIVES/OBJECTIVE:Clopidogrel is effective at decreasing cardiovascular events in patients with peripheral artery disease (PAD); however, its effect on limb outcomes are less known. This study investigated the variability in response to clopidogrel and its relationship with clinical limb outcomes. METHODS: RESULTS: CONCLUSIONS:Among patients undergoing lower extremity revascularization on clopidogrel, higher baseline percent aggregation is associated with increased risk for major adverse limb events.

BACKGROUND:Recommended systolic blood pressure (SBP) targets often do not consider the relationship of low diastolic blood pressure (DBP) levels with cardiovascular disease (CVD) and all-cause mortality risk, which is especially relevant for older people with concurrent comorbidities.We examined the relationship of DBP levels to CVD and all-cause mortality in older women in the Women's Health Initiative Long Life Study (WHI-LLS). METHODS:The study sample included 7,875 women (mean age: 79 years) who underwent a BP measurement at an in-person home visit conducted in 2012-2013. CVD and all-cause mortality were centrally adjudicated. Hazard ratios (HR) were obtained from adjusted Cox proportional hazards models. RESULTS:After 5 years follow-up, all-cause mortality occurred in 18.4% of women. Compared to a DBP of 80 mmHg, the fully adjusted hazards ratio (HR) for mortality was 1.33 (95% CI: 1.04-1.71) for a DBP of 50 mmHg and 1.67 (95% CI: 1.29-2.16) for a DBP of 100 mmHg. The HRs for CVD were 1.14 (95% CI: 0.78-1.67) for a DBP of 50 mmHg and HR 1.50 (95% CI: 1.03-2.17) for a DBP of 100 mmHg. The nadir DBP associated with lowest mortality risk was 72 mmHg overall. CONCLUSIONS:In older women, consideration should be given to the potential adverse effects of low and high DBP. Low DBP may serve as a risk marker. DBP target levels between 68 and 75 mmHg may avoid higher mortality risk.

Background Peripheral artery disease (PAD) is associated with heightened risk for major adverse cardiovascular and limb events, but data on the burden of risk for total (first and potentially subsequent) events, and the association with polyvascular disease, are limited. This post hoc analysis of the EUCLID (Examining Use of Ticagrelor in Peripheral Artery Disease) trial evaluated total cardiovascular and limb events among patients with symptomatic PAD, overall and by number of symptomatic vascular territories. Methods and Results In the EUCLID trial, patients with symptomatic PAD (lower extremity revascularization >30 days before randomization or ankle-brachial index ≤0.80) were randomized to treatment with ticagrelor or clopidogrel. Relative effects on total events (cardiovascular death; nonfatal myocardial infarction and ischemic stroke; acute limb ischemia, unstable angina, and transient ischemic attack requiring hospitalization; coronary, carotid, and peripheral revascularization procedures; and amputation for symptomatic PAD) were summarized by hazard ratios (HRs), whereas absolute risks were estimated by incidence rates and mean cumulative functions. Among 13 885 randomized patients, 7600 total cardiovascular and limb events occurred during a median 2.7 years of follow-up, translating to 60.0 and 62.5 events per 100 patients through 3 years for the ticagrelor and clopidogrel groups, respectively (HR, 0.96; 95% CI, 0.89-1.03; P=0.27). Among 1393 patients with disease in 3 vascular territories, event accrual rates through 3 years for the ticagrelor and clopidogrel groups were 87.3 and 97.7 events per 100 patients, respectively. Absolute risk reductions for ticagrelor relative to clopidogrel at 3 years were -0.2, 6.7, and 10.3 events per 100 patients for 1, 2, and 3 affected vascular territories, respectively (P

Prior observational studies suggest rivaroxaban is safe and effective among patients with morbid obesity who suffered a venous thromboembolism (VTE) event, but existing data are more limited in the broader population of VTE patients with obesity. This study assessed VTE recurrence, major bleeding, healthcare resource utilization, and healthcare costs among VTE patients with obesity who received rivaroxaban versus warfarin. VTE patients with obesity who initiated rivaroxaban or warfarin after a first VTE (index date) were identified from the IQVIA PharMetrics® Plus database (01/02/2011-09/30/2019). The follow-up period spanned from the index date until health plan disenrollment, end of data availability, cancer diagnosis/treatment, end of the 12 month post-index period, or (for the analysis of major bleeding) anticoagulant discontinuation or switch. Patient characteristics were balanced using inverse probability of treatment weighting. The weighted rivaroxaban (N = 8666) and warfarin cohorts (N = 5946) were well balanced (mean age = 51 years, females = 52%). Over a 9.6 months mean observation period, rivaroxaban users had a significantly lower risk of VTE recurrence [7.0% vs. 8.2%, HR(95% CI) = 0.85(0.75;0.97)] and a similar risk of major bleeding [4.1% vs. 3.6%, HR(95% CI) = 1.11(0.89;1.37)] relative to warfarin users at 12 months. Relative to warfarin users, rivaroxaban users had significantly fewer all-cause outpatient visits [RR(95% CI) = 0.71(0.70;0.74)]. The higher pharmacy costs incurred by rivaroxaban recipients (cost difference = $1252) were offset by lower medical costs (cost difference = - $2515, all p < 0.05) compared with warfarin recipients. Our findings suggest that rivaroxaban is safe and effective versus warfarin, and associated with lower medical costs among VTE patients with obesity.

Background Vascular function is compromised in Alzheimer disease (AD) years before amyloid and tau pathology are detected and a substantial body of work shows abnormal platelet activation states in patients with AD. The aim of our study was to investigate whether platelet function in middle age is independently associated with future risk of AD. Methods and Results We examined associations of baseline platelet function with incident dementia risk in the community-based FHS (Framingham Heart Study) longitudinal cohorts. The association between platelet function and risk of dementia was evaluated using the cumulative incidence function and inverse probability weighted Cox proportional cause-specific hazards regression models, with adjustment for demographic and clinical covariates. Platelet aggregation response was measured by light transmission aggregometry. The final study sample included 1847 FHS participants (average age, 53.0 years; 57.5% women). During follow-up (median, 20.5 years), we observed 154 cases of incident dementia, of which 121 were AD cases. Results from weighted models indicated that platelet aggregation response to adenosine diphosphate 1.0 µmol/L was independently and positively associated with dementia risk, and it was preceded in importance only by age and hypertension. Sensitivity analyses showed associations with the same directionality for participants defined as adenosine diphosphate hyper-responders, as well as the platelet response to 0.1 µmol/L epinephrine. Conclusions Our study shows individuals free of antiplatelet therapy with a higher platelet response are at higher risk of dementia in late life during a 20-year follow-up, reinforcing the role of platelet function in AD risk. This suggests that platelet phenotypes may be associated with the rate of dementia and potentially have prognostic value.

BACKGROUND:Patients with significant (≥50%) left main disease (LMD) have a high risk of cardiovascular events, and guidelines recommend revascularization to improve survival. However, the impact of intermediate LMD (stenosis, 25%-49%) on outcomes is unclear. METHODS:Randomized ISCHEMIA (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) participants who underwent coronary computed tomography angiography at baseline were categorized into those with (25%-49%) and without (<25%) intermediate LMD. The primary outcome was a composite of cardiovascular mortality, myocardial infarction (MI), or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. The primary quality of life outcome was the Seattle Angina Questionnaire summary score. RESULTS: CONCLUSIONS:In the ISCHEMIA trial, there was no meaningful heterogeneity of treatment benefit from an invasive strategy regardless of intermediate LMD status except for a greater absolute risk reduction in nonprocedural MI with invasive management in those with intermediate LMD. An invasive strategy increased procedural MI, reduced nonprocedural MI, and improved angina-related quality of life. REGISTRATION/BACKGROUND:URL: https://www. CLINICALTRIALS/RESULTS:gov; Unique identifier: NCT01471522.