Etiology and outcomes of amputation in patients with peripheral artery disease in the EUCLID trial.

OBJECTIVE: Amputation remains a frequent and feared outcome in patients with peripheral artery disease (PAD). Although typically characterized as major or minor on the extent of tissue loss, the etiologies and outcomes after amputation by extent are not well-understood. In addition, emerging data suggest that the drivers and outcomes of amputation in patients with PAD may differ in those with and without diabetes mellitus (DM). METHODS: The EUCLID trial randomized 13,885 patients with symptomatic PAD, including 5345 with concomitant diabetes, to ticagrelor or clopidogrel and followed them for long-term outcomes. Amputations were prospectively reported by trial investigators. Their primary and contributing drivers were adjudicated using safety data, including infection, ischemia, or multifactorial etiologies. Outcomes following major and minor amputations were analyzed, including recurrent amputation, major adverse limb events, adverse cardiovascular events, and mortality. Multivariable logistic regression models were used to identify independent predictors of minor amputations. Analyses were performed overall and stratified by the presence or absence of DM at baseline. RESULTS: Of the patients randomized, 398 (2.9%) underwent at least one lower extremity nontraumatic amputation, for a total of 511 amputations (255 major and 256 minor) over a median of 30 months. A history of minor amputation was the strongest independent predictor for a subsequent minor amputation (odds ratio, 7.29; 95% confidence interval, 5.17-10.30; P < .001) followed by comorbid DM (odds ratio, 4.60; 95% confidence interval, 3.16-6.69; P < .001). Compared with patients who had a major amputation, those with a minor amputation had similar rates of subsequent major amputation (12.2% vs 13.6%), major adverse limb events (15.1% vs 14.9%), and major adverse cardiovascular events (17.6% vs 16.3%). Ischemia alone was the primary driver of amputation (51%), followed by infection alone (27%), and multifactorial etiologies (22%); however, infection was the most frequent driver in those with DM (58%) but not in those without DM (15%). CONCLUSIONS: Outcomes after amputation remain poor regardless of whether they are categorized as major or minor. The pattern of amputation drivers in PAD differs by history of DM, with infection being the dominant etiology in those with DM and ischemia in those without DM. Greater focus is needed on the prognostic importance of minor amputation and of the multifactorial etiologies of amputation in PAD. Nomenclature with anatomical description of amputations and eliminating terms "major" or "minor" would seem appropriate.

Association of Heart Failure With Outcomes Among Patients With Peripheral Artery Disease: Insights From EUCLID.

Background Peripheral artery disease (PAD) and heart failure (HF) are each independently associated with poor outcomes. Risk factors associated with new-onset HF in patients with primary PAD are unknown. Furthermore, how the presence of HF is associated with outcomes in patients with PAD is unknown. Methods and Results This analysis examined risk relationships of HF on outcomes in patients with symptomatic PAD randomized to ticagrelor or clopidogrel as part of the EUCLID (Examining Use of Ticagrelor in Peripheral Arterial Disease) trial. Patients were stratified based on presence of HF at enrollment. Cox models were used to determine the association of HF with outcomes. A separate Cox model was used to identify risk factors associated with development of HF during follow-up. Patients with PAD and HF had over twice the rate of concomitant coronary artery disease as those without HF. Patients with PAD and HF had significantly increased risk of major adverse cardiovascular events (hazard ratio [HR], 1.31; 95% CI, 1.13-1.51) and all-cause mortality (HR, 1.39; 95% CI, 1.19-1.63). In patients with PAD, the presence of HF was associated with significantly less bleeding (HR, 0.65; 95% CI, 0.45-0.96). Characteristics associated with HF development included age ≥66 (HR, 1.29; 95% CI, 1.18-1.40 per 5 years), diabetes mellitus (HR, 1.85; 95% CI, 1.41-2.43), and weight (bidirectionally associated, ≥76 kg, HR, 0.77; 95% CI, 0.64-0.93; <76 kg, HR, 1.12; 95% CI, 1.07-1.16). Conclusions Patients with PAD and HF have a high rate of coronary artery disease with a high risk for major adverse cardiovascular events and death. These data support the possible need for aggressive treatment of (recurrent) atherosclerotic disease in PAD, especially patients with HF.

Cause of Death Among Patients With Peripheral Artery Disease: Insights From the EUCLID Trial.

BACKGROUND: Peripheral artery disease is common and associated with high mortality. There are limited data detailing causes of death among patients with peripheral artery disease. METHODS: EUCLID (Examining Use of Ticagrelor in Peripheral Artery Disease) was a randomized clinical trial that assigned patients with peripheral artery disease to clopidogrel or ticagrelor. We describe the causes of death in EUCLID using mortality end points adjudicated through a clinical events classification process. The association between baseline factors and cardiovascular death was evaluated by Cox proportional hazards modeling. The competing risk of noncardiovascular death was assessed by the cumulative incidence function for cardiovascular death and the Fine and Gray method to ascertain the association between baseline characteristics and cardiovascular mortality. RESULTS: A total of 1263 out of 13 885 (9.1%) patients died (median follow-up: 30 months). There were 706 patients (55.9%) with a cardiovascular cause of death and 522 (41.3%) with a noncardiovascular cause of death. The most common cause of cardiovascular death was sudden cardiac death (20.1%); while myocardial infarction (5.2%) and ischemic stroke (3.2%) were uncommon. The most common causes of noncardiovascular death were malignancies (17.9%) and infections (11.9%). The factor most associated with a higher risk of cardiovascular death was age per 5 year increase (HR, 1.26 [95% CI, 1.20-1.32]). Female sex was associated with a lower risk of cardiovascular death (HR, 0.68 [95% CI, 0.56-0.82]). To evaluate the effect of noncardiovascular death as a competing risk, we superimposed the cumulative incidence function curve with the Kaplan-Meier curve. These curves closely approximated each other. After accounting for the competing risk of noncardiovascular death, the magnitude and direction of the factors associated with cardiovascular death were minimally changed. CONCLUSIONS: Among patients with symptomatic peripheral artery disease, noncardiovascular causes of death reflected a high proportion (40%) of deaths. Accounting for noncardiovascular deaths as a competing risk, there was not a significant change in the risk estimation for cardiovascular death. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01732822.

Association of Health Status Scores With Cardiovascular and Limb Outcomes in Patients With Symptomatic Peripheral Artery Disease: Insights From the EUCLID (Examining Use of Ticagrelor in Symptomatic Peripheral Artery Disease) Trial.

Background There are limited data on health status instruments in patients with peripheral artery disease and cardiovascular and limb events. We evaluated the relationship between health status changes and cardiovascular and limb events. Methods and Results In an analysis of the EUCLID (Examining Use of Ticagrelor in Symptomatic Peripheral Artery Disease) trial, we examined the characteristics of 13 801 patients by tertile of health status instrument scores collected in the trial (EuroQol 5-Dimensions [EQ-5D], EQ visual analog scale [VAS], and peripheral artery questionnaire). We assessed the association between the baseline health status measurements and major adverse cardiovascular events, major adverse limb events, and lower-extremity revascularization procedures during trial follow-up and the association between 12-month health status change scores and subsequent end points during follow-up. There were 13 217 (95%) patients with EQ-5D scores, 13 533 (98%) with VAS scores, and 4431 (32%) with peripheral artery questionnaire scores. Patients in the lowest baseline EQ-5D tertile (0 to <0.69) were more likely to be female with severe claudication compared with the highest tertile (0.79-1.0; P<0.01). Patients in the lowest VAS (0-60) and peripheral artery questionnaire (0-49) tertiles had lower ankle-brachial indices compared with the highest tertiles (80-100 and 76-108, respectively; P<0.01). There was a significant association between baseline EQ-5D, VAS, and peripheral artery questionnaire scores and adjusted major adverse cardiovascular events, major adverse limb events, and lower-extremity revascularization (P<0.05). Improved EQ-5D and VAS scores over 12 months were associated with reduced risk of subsequent major adverse cardiovascular events or lower-extremity revascularization (all P<0.01). Conclusions Although health status instruments are rarely used in clinical practice, these measures are associated with outcomes, including major adverse cardiovascular events, major adverse limb events, and lower-extremity revascularization. Further research is needed to determine the relationship between changes in these instruments, revascularization, and outcomes.

Incidence, Characteristics, and Outcomes of Myocardial Infarction in Patients With Peripheral Artery Disease: Insights From the EUCLID Trial.

Importance: Patients with peripheral artery disease (PAD) are at high risk for myocardial infarction (MI). Objective: To characterize the incidence and types of MI in a PAD population, identify factors associated with MI, and determine the association of MI with cardiovascular mortality and acute limb ischemia. Design, Setting, and Participants: The Study Comparing Cardiovascular Effects of Ticagrelor and Clopidogrel in Patients With Peripheral Artery Disease (EUCLID) was a double-blind randomized clinical trial conducted at 811 sites in 28 countries that randomized 13 885 patients with symptomatic PAD to monotherapy with ticagrelor or clopidogrel. Participants had an ankle-brachial index (ABI) of 0.80 or less or previous lower extremity revascularization. Median follow-up was 30 months. For these analyses, patients were evaluated for MI occurrence during follow-up irrespective of treatment. Data were analyzed from June 2017 to September 2018. Main Outcomes and Measures: An adjudication clinical events committee classified MI as type 1 (spontaneous), type 2 (secondary), type 3 (sudden cardiac death), type 4a (less than 48 hours after percutaneous coronary intervention), type 4b (definite stent thrombosis), or type 5 (less than 72 hours after coronary artery bypass graft). A multivariate regression model was developed by stepwise selection to identify factors associated with MI, and a time-dependent multivariate Cox regression analysis was performed to determine the association of MI with cardiovascular death and acute limb ischemia requiring hospitalization. Results: Of the 13 885 patients included in this analysis, 9997 (72.0%) were male, and the median (interquartile range) age was 66 (60-73) years. Myocardial infarction occurred in 683 patients (4.9%; 2.4 events per 100 patient-years) during a median follow-up of 30 months. Patients experiencing MI were older (median [interquartile range] age, 69 [62-75] vs 66 [60-72] years), more likely to have diabetes (349 of 683 [51.1%] vs 4996 of 13 202 [37.8%]) or a previous lower extremity revascularization (466 of 683 [68.2%] vs 7409 of 13 202 [56.1%]), and had a lower ABI (if included by ABI) compared with censored patients. Of the 683 patients with MI during follow-up, the most common MI type was type 1 (405 [59.3%]), followed by type 2 (236 [34.6%]), type 4a (14 [2.0%]), type 3 (12 [1.8%]), type 4b (11 [1.6%]), and type 5 (5 [0.7%]). Postrandomization MI was independently associated with cardiovascular death (adjusted hazard ratio, 9.0; 95% CI, 7.3-11.2; P < .001) and acute limb ischemia requiring hospitalization (adjusted hazard ratio, 2.5; 95% CI, 1.3-5.0; P = .008). Conclusions and Relevance: Approximately 5% of patients with symptomatic PAD had an MI during a median follow-up of 30 months. Type 1 MI (spontaneous) was the most common MI type; however, one-third of MIs were type 2 MI (secondary). More research is needed to identify therapies to reduce the risk of MI in patients with PAD and to improve management of type 2 MI. Trial Registration: ClinicalTrials.gov Identifier: NCT01732822.

Cardiovascular Outcomes After Lower Extremity Endovascular or Surgical Revascularization: The EUCLID Trial.

BACKGROUND: Lower extremity revascularization (LER) is a common treatment in patients with peripheral artery disease (PAD), but long-term outcomes are poorly defined. OBJECTIVES: The aim was to analyze LER in the EUCLID (Examining Use of tiCagreLor In paD) trial to determine predictors and cardiovascular outcomes. METHODS: Patients were grouped according to whether they received a post-randomization LER (n = 1,738) or not (n = 12,147). All variables were assessed for significance in univariable and parsimonious multivariable models. The primary endpoint was myocardial infarction, ischemic stroke, or cardiovascular death; major adverse limb events (MALE) included acute limb ischemia or major amputation. RESULTS: A post-randomization LER occurred in 12.5% of patients and was an endovascular LER in 74.7%. Endovascular LERs were performed more often in North America, whereas surgical procedures occurred more frequently in Europe. Independent factors predicting LER were prior and type of prior LER, geographic region, limb symptoms, diabetes, and smoking. A post-randomization LER was associated with an increased risk for the primary endpoint (hazard ratio: 1.60; 95% confidence interval: 1.35 to 1.90; p < 0.0001) and MALE (hazard ratio: 12.0; 95% confidence interval: 9.47 to 15.30; p < 0.0001). Event rates for the primary endpoint after LER were numerically higher in the surgical subgroup, but MALE were similar between surgical and endovascular LER. CONCLUSIONS: In the EUCLID trial, LER was most often endovascular. Following LER, there was an increased hazard for the primary endpoint (with higher event rates in the surgical group) and a markedly increased risk for MALE events (with similar event rates between surgical and endovascular LER procedures). (A Study Comparing Cardiovascular Effects of Ticagrelor and Clopidogrel in Patients With Peripheral Artery Disease [EUCLID]; NCT01732822).

Ticagrelor versus clopidogrel in patients with symptomatic peripheral artery disease and prior coronary artery disease: Insights from the EUCLID trial.

Patients with peripheral artery disease (PAD) are at heightened risk of cardiovascular morbidity and mortality. We sought to evaluate the risk of concomitant coronary artery disease (CAD) in patients with symptomatic PAD versus PAD without diagnosed CAD, and whether ticagrelor was superior to clopidogrel in reducing that risk. The EUCLID trial randomized 13,885 patients with PAD to antithrombotic monotherapy with ticagrelor or clopidogrel. CAD was defined as prior myocardial infarction (MI), percutaneous coronary intervention (PCI), or coronary artery bypass graft (CABG) surgery. Median follow-up was 30 months. Among 4032 (29%) patients with PAD and CAD, 63% had prior MI, 54% prior PCI, and 38% prior CABG. After adjustment for baseline characteristics, patients with PAD and CAD had significantly higher rates of the primary endpoint (cardiovascular death/MI/stroke, 15.3% vs 8.9%, hazard ratio (HR) 1.50, 95% CI: 1.13-1.99; p=0.005), but no statistically significant increase in acute limb ischemia (HR 1.28, 95% CI: 0.57-2.85; p=0.55) or major bleeding (HR 1.10, 95% CI: 0.49-2.48; p=0.81) versus PAD without CAD. Among patients with PAD and CAD, there was no differential treatment effect between ticagrelor versus clopidogrel for the primary efficacy endpoint (HR 1.02, 95% CI: 0.87-1.19; p=0.84), acute limb ischemia (HR 1.03, 95% CI: 0.63-1.69; p=0.89), or major bleeding (HR 1.06, 95% CI: 0.66-1.69; p=0.81). There was a statistically significant interaction between prior coronary stent placement and study treatment ( p=0.03) with a numerical reduction in the primary efficacy endpoint with ticagrelor versus clopidogrel (13.8% vs 16.8%, HR 0.82, 95% CI: 0.65-1.03; p=0.09). Patients with PAD and prior CAD had higher composite rates of cardiovascular death, MI, and ischemic stroke versus PAD without diagnosed CAD. There were no significant differences between ticagrelor and clopidogrel in cardiovascular events or major bleeding. ClinicalTrials.gov Identifier: NCT01732822.

International Validation of the Thrombolysis in Myocardial Infarction (TIMI) Risk Score for Secondary Prevention in Post-MI Patients: A Collaborative Analysis of the Chronic Kidney Disease Prognosis Consortium and the Risk Validation Scientific Committee.

BACKGROUND: The Thrombolysis in Myocardial Infarction (TIMI) Risk Score for Secondary Prevention (TRS2°P), a 0-to-9-point system based on the presence/absence of 9 clinical factors, was developed to classify the risk of major adverse cardiovascular events (MACE) (a composite of cardiovascular death, recurrent myocardial infarction, or ischemic stroke) among patients with a recent myocardial infarction. Its performance has not been examined internationally outside of a clinical trial setting. METHODS AND RESULTS: We evaluated the performance of TRS2°P for predicting MACE in 53 599 patients with recent myocardial infarction in 5 international cohorts from New Zealand, South Korea, Sweden, and the United States participating in the Chronic Kidney Disease Prognosis Consortium. Overall, there were 19 444 cases of MACE across 5 cohorts over a mean follow-up of 5 years, and the overall MACE rate ranged from 5.0 to 18.4 (per 100 person-years). The TRS2°P showed modest calibration (Brier score ranged from 0.144 to 0.173) and discrimination (C-statistics >0.61 in all studies except 1 from Korea with 0.55) across cohorts relative to its original Brier score of 0.098 and C-statistic of 0.67 in the derived data set. Although there was some heterogeneity across cohorts, the 9 predictors in the TRS2°P were generally associated with higher MACE risk, with strongest associations observed (meta-analyzed adjusted hazard ratio 1.6-1.7) for history of heart failure, age ≥75 years, and prior stroke, followed by peripheral artery disease, kidney dysfunction, diabetes mellitus, and hypertension (hazard ratio 1.3-1.4). Prior coronary bypass graft surgery and smoking did not reach statistical significance (hazard ratio ≈1.1). CONCLUSIONS: TRS2°P, a simple scoring system with 9 routine clinical factors, was modestly predictive of secondary events when applied in patients with recent myocardial infarction from diverse clinical and geographic settings.

Predictors of Bleeding in Patients with Symptomatic Peripheral Artery Disease: A Cohort Study Using The Health Improvement Network in the United Kingdom.

The purpose of this analysis was to assess potential predictors of intra-cranial bleeding (ICB) and gastrointestinal bleeding (GIB) in patients with symptomatic peripheral artery disease (PAD) in UK primary care. Patients with symptomatic PAD diagnosed from 2000 to 2010 were identified from The Health Improvement Network (THIN; N = 28,484). A nested case-control analysis, adjusted for potential confounders, was performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for potential predictors of ICB or GIB. For GIB, follow-up was restricted to Hospital Episode Statistics-linked THIN practices. Median follow-up was 6 years. For ICB (153 cases), the OR (95% CI) was 3.85 (1.33-11.13) for previous ICB, 0.90 (0.61-1.34) for treated hypertension, 1.59 (0.65-3.87) for untreated hypertension and 1.38 (0.80-2.36) for current smoking. ORs for ICB were 0.78 (0.50-1.21), 0.40 (0.09-1.82) and 1.27 (0.47-3.47) with use of acetylsalicylic acid (ASA), clopidogrel and warfarin monotherapy, respectively, compared with non-use of such therapy. For GIB (506 cases), the OR was 1.40 (1.05-1.86) for peptic ulcer disease, 3.20 (1.81-5.64) for dual anti-platelet therapy use, 1.96 (1.46-2.64) for non-steroidal anti-inflammatory drug (NSAID) use and 1.01 (0.80-1.28) for proton pump inhibitor use. ORs for GIB were 1.78 (1.39-2.30), 2.03 (1.05-3.93) and 1.25 (0.72-2.16) with ASA, clopidogrel and warfarin monotherapy, respectively, compared with non-use. Previous ICB was a risk factor for ICB. Use of anti-platelet therapy or NSAIDs increased GIB risk. Identifying bleeding predictors could help optimize treatment strategies for patients with PAD.

Outcomes of Patients with Critical Limb Ischaemia in the EUCLID Trial.

OBJECTIVES: Critical limb ischaemia (CLI) implies an increased risk of cardiovascular morbidity and mortality, and the optimal antithrombotic treatment is not established. DESIGN, MATERIALS, METHODS: The EUCLID trial investigated the effect of monotherapy with ticagrelor versus clopidogrel in 13,885 patients with peripheral artery disease (PAD); the primary endpoint was cardiovascular death, myocardial infarction, or ischaemic stroke. Patients planned for revascularisation or amputation within 3 months, were excluded. This analysis focuses on the subgroup with CLI, defined by rest pain (58.8%), major (9.0%) or minor (32.2%) tissue loss. RESULTS: In EUCLID, 643 patients (4.6%) had CLI at baseline. Diabetes mellitus was more common in the CLI group, while coronary disease, carotid disease, and hypertension were more common in the non-CLI group. A majority of CLI patients (62.1%) had only lower extremity PAD. In patients enrolled on the ankle brachial index (ABI) criteria, ABI was 0.55 ± 0.21 (mean ± SD) for those with CLI versus 0.63 ± 0.15 for those without CLI. The primary efficacy endpoint significantly increased among patients with CLI compared with those without CLI with a rate of 8.85 versus 4.28/100 patient years (adjusted for baseline characteristics hazard ratio [HR] 1.43 [95% CI 1.16-1.76]; p = 0.0009). When acute limb ischaemia requiring hospitalisation was added to the model, significant differences remained (adjusted HR 1.38, [95% CI 1.13-1.69]; p = 0.0016). The 1 year mortality was 8.9%. A trend towards increased lower limb revascularisation among those with CLI was observed. Bleeding (TIMI major, fatal, intracranial) did not differ between those with and without CLI. CONCLUSIONS: Nearly 5% of patients enrolled in EUCLID had CLI at baseline. Milder forms of CLI dominated, a result of the trial design. Patients with CLI had a significantly higher rate of cardiovascular mortality and morbidity versus those without CLI. Further efforts are required to reduce the risk of cardiovascular events in PAD, especially in patients with CLI. CLINICALTRIALS.GOV: NCT01732822.

Cardiovascular outcomes for patients with symptomatic peripheral artery disease: A cohort study in The Health Improvement Network (THIN) in the UK.

Background Few data are available on risk factors and associations with outcomes in symptomatic peripheral artery disease (PAD) populations in primary care. We assessed characteristics and cardiovascular outcomes in patients with and those without symptomatic peripheral artery disease in UK primary care, and quantified risk factors for cardiovascular outcomes in patients with peripheral artery disease. Methods Among patients in The Health Improvement Network (THIN) aged 50-89 years in 2000-2010, a symptomatic peripheral artery disease cohort ( n = 28,484) and a matched comparison cohort without peripheral artery disease ( n = 113,940) were identified using Read codes. Cox proportional hazard ratios (HRs) and 95% confidence intervals (CIs) for cardiovascular outcomes were calculated, adjusted for potential confounders. Results The incidence of all-cause death per 1000 person-years was 83.22 and 50.46 in the peripheral artery disease and non-peripheral artery disease cohort, respectively (HR 1.41; 95% CI 1.68-1.43). The incidence of composite cardiovascular outcome (myocardial infarction, ischaemic stroke or cardiovascular-related death) per 1000 person-years was 31.87 and 14.63 in the peripheral artery disease and non-peripheral artery disease cohort, respectively (HR 1.71; 95% CI 1.65-1.77). Risk factors for composite cardiovascular outcome in patients with peripheral artery disease were older age (≥75 years vs. 50-64 years: HR 2.37; 95% CI 2.20-2.55), current smoking (1.26; 1.17-1.35), comorbid diabetes (1.42; 1.32-1.52), heart failure (1.31; 1.20-1.44), atrial fibrillation (1.32; 1.18-1.47, previous myocardial infarction (1.29; 1.20-1.39) and previous ischaemic stroke (1.77; 1.63-1.93). Conclusion Patients with symptomatic peripheral artery disease in a clinical practice population have a high risk of death and cardiovascular-related outcomes. Minimising risk is important in the ongoing management of these patients.

Ticagrelor versus Clopidogrel in Symptomatic Peripheral Artery Disease.

BACKGROUND: Peripheral artery disease is considered to be a manifestation of systemic atherosclerosis with associated adverse cardiovascular and limb events. Data from previous trials have suggested that patients receiving clopidogrel monotherapy had a lower risk of cardiovascular events than those receiving aspirin. We wanted to compare clopidogrel with ticagrelor, a potent antiplatelet agent, in patients with peripheral artery disease. METHODS: In this double-blind, event-driven trial, we randomly assigned 13,885 patients with symptomatic peripheral artery disease to receive monotherapy with ticagrelor (90 mg twice daily) or clopidogrel (75 mg once daily). Patients were eligible if they had an ankle-brachial index (ABI) of 0.80 or less or had undergone previous revascularization of the lower limbs. The primary efficacy end point was a composite of adjudicated cardiovascular death, myocardial infarction, or ischemic stroke. The primary safety end point was major bleeding. The median follow-up was 30 months. RESULTS: The median age of the patients was 66 years, and 72% were men; 43% were enrolled on the basis of the ABI and 57% on the basis of previous revascularization. The mean baseline ABI in all patients was 0.71, 76.6% of the patients had claudication, and 4.6% had critical limb ischemia. The primary efficacy end point occurred in 751 of 6930 patients (10.8%) receiving ticagrelor and in 740 of 6955 (10.6%) receiving clopidogrel (hazard ratio, 1.02; 95% confidence interval [CI], 0.92 to 1.13; P=0.65). In each group, acute limb ischemia occurred in 1.7% of the patients (hazard ratio, 1.03; 95% CI, 0.79 to 1.33; P=0.85) and major bleeding in 1.6% (hazard ratio, 1.10; 95% CI, 0.84 to 1.43; P=0.49). CONCLUSIONS: In patients with symptomatic peripheral artery disease, ticagrelor was not shown to be superior to clopidogrel for the reduction of cardiovascular events. Major bleeding occurred at similar rates among the patients in the two trial groups. (Funded by AstraZeneca; EUCLID ClinicalTrials.gov number, NCT01732822 .).

Peripheral artery disease: epidemiology and global perspectives.

Global populations are undergoing a major epidemiological transition in which the burden of atherosclerotic cardiovascular diseases is shifting rapidly from high-income to low-income and middle-income countries (LMICs). Peripheral artery disease (PAD) is no exception, so that greater focus is now required on the prevention and management of this disease in less-advantaged countries. In this Review, we examine the epidemiology of PAD and, where feasible, take a global perspective. However, the dearth of publications in LMICs means an unavoidable over-reliance on studies in high-income countries. Research to date suggests that PAD might affect a greater proportion of women than men in LMICs. Although factors such as poverty, industrialization, and infection might conceivably influence the development of PAD in such settings, the ageing of the population and increase in traditional cardiovascular risk factors, such as smoking, diabetes mellitus, and hypertension, are likely to be the main driving forces.

Ticagrelor Compared With Clopidogrel in Patients With Prior Lower Extremity Revascularization for Peripheral Artery Disease.

BACKGROUND: In patients with symptomatic peripheral artery disease with a history of limb revascularization, the optimal antithrombotic regimen for long-term management is unknown. METHODS: The EUCLID trial (Examining Use of Ticagrelor In PAD) randomized 13 885 patients with peripheral artery disease to treatment with ticagrelor 90 mg twice daily or clopidogrel 75 mg daily. Patients were enrolled based on an abnormal ankle-brachial index ≤0.80 or a previous lower extremity revascularization. This analysis focuses on the 7875 (57%) patients enrolled based on the previous lower extremity revascularization criterion. Patients could not be enrolled within 30 days of most recent revascularization, and patients with an indication for dual antiplatelet therapy were excluded. The primary efficacy end point was a composite of cardiovascular death, myocardial infarction, or ischemic stroke. The primary safety end point was major bleeding. RESULTS: Patients with a previous revascularization had a mean age of 66 years, 73% were male, and the median baseline ankle-brachial index was 0.78. After adjustment for baseline characteristics, patients enrolled based on previous revascularization had similar rates of the primary composite end point (hazard ratio [HR] 1.10, 95% confidence interval [CI] 0.98-1.23, P=0.12) and statistically significantly higher rates of myocardial infarction (HR 1.29, 95% CI 1.08-1.55, P=0.005) and acute limb ischemia (HR 4.23, 95% CI 2.86-6.25, P<0.001) when compared with patients enrolled based on ankle-brachial index criteria. No differences in ticagrelor- versus clopidogrel-treated patients were found for the primary efficacy end point (11.4% vs 11.3%; HR 1.01, 95% CI 0.88-1.15; P=0.90), all-cause mortality (9.2% vs 9.2%; HR 0.99, 95% CI 0.86-1.15; P=0.93), acute limb ischemia (2.5% vs 2.5%; HR 1.03, 95% CI 0.78-1.36; P=0.84), or major bleeding (1.9% vs 1.8%; HR 1.15, 95% CI 0.83-1.59; P=0.41). The median duration of follow-up was ≈30 months. CONCLUSIONS: After adjustment for baseline characteristics, patients enrolled based on previous revascularization for peripheral artery disease had higher rates of myocardial infarction and acute limb ischemia, with similar composite rates of cardiovascular death, myocardial infarction, and stroke when compared with patients enrolled based on the ankle-brachial index criterion. No significant differences were found between ticagrelor and clopidogrel for reduction of cardiovascular or acute limb events. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01732822.

Design and rationale for the Effects of Ticagrelor and Clopidogrel in Patients with Peripheral Artery Disease (EUCLID) trial.

BACKGROUND: Despite overwhelming data demonstrating the efficacy of antiplatelet therapy in heart disease and stroke, data in peripheral artery disease (PAD) are less compelling. Aspirin has modest evidence supporting a reduction in cardiovascular events in patients with PAD, whereas clopidogrel monotherapy may be more effective in PAD. Ticagrelor, a potent, reversibly binding P2Y12 receptor antagonist, is beneficial in patients with acute coronary syndrome and prior myocardial infarction. The EUCLID trial is designed to address the need for effective antiplatelet therapy in PAD to decrease the risk of cardiovascular events. STUDY DESIGN: EUCLID is a randomized, double-blind, parallel-group, multinational clinical trial designed to evaluate the efficacy and safety of ticagrelor compared with clopidogrel for the prevention of major adverse cardiovascular events in subjects with symptomatic PAD. Subjects with established PAD will be randomized in a 1:1 fashion to ticagrelor 90 mg twice daily or clopidogrel 75 mg daily. The primary end point is a composite of cardiovascular death, myocardial infarction, or ischemic stroke. Other end points address limb events including acute leg ischemia, need for revascularization, disease progression by ankle-brachial index, and quality of life. The primary safety objective is Thrombolysis in Myocardial Infarction-defined major bleeding. Recruitment began in December 2012 and was completed in March 2014; 13,887 patients were randomized. The trial will continue until at least 1,364 adjudicated primary end points occur. CONCLUSIONS: The EUCLID study is investigating whether treatment with ticagrelor versus clopidogrel, given as antiplatelet monotherapy, will reduce the incidence of cardiovascular and limb-specific events in patients with symptomatic PAD.

Smoking, hypercholesterolaemia and hypertension as risk factors for cognitive impairment in older adults.

BACKGROUND: the prevalence of all types of cognitive impairment, including dementia, is increasing but knowledge of aetiological factors is still evolving. OBJECTIVE: this study aimed to evaluate the association between cardiovascular risk factors and cognitive function in older persons. DESIGN, SETTING AND SUBJECTS: a population-based cohort design involving 2,312 men and women (aged 50-75) enrolled in the University of Edinburgh Aspirin for Asymptomatic Atherosclerosis trial. METHODS: cognitive tests included the Mill Hill Vocabulary Scale, auditory verbal learning test (AVLT), digit symbol test, verbal fluency test (VFT), Raven's Progressive Matrices and the trail making test. A 'g' score (measure of general intelligence) was computed for each subject. Regression analysis was used to evaluate the association between relevant variables. RESULTS: higher diastolic BP was negatively associated with AVLT (ß = -0.153, P < 0.01), and with an estimated decline on AVLT (ß = -0.125, P < 0.01). Smoking was negatively associated with all the cognitive variables except VFT. The total cholesterol level was not associated with cognitive function or estimated decline. CONCLUSIONS: smoking and elevated blood pressure may be risk factors for cognitive decline, and thus potential targets for preventive and therapeutic interventions.

C-reactive protein, fibrinogen, and cardiovascular disease prediction.

BACKGROUND: There is debate about the value of assessing levels of C-reactive protein (CRP) and other biomarkers of inflammation for the prediction of first cardiovascular events. METHODS: We analyzed data from 52 prospective studies that included 246,669 participants without a history of cardiovascular disease to investigate the value of adding CRP or fibrinogen levels to conventional risk factors for the prediction of cardiovascular risk. We calculated measures of discrimination and reclassification during follow-up and modeled the clinical implications of initiation of statin therapy after the assessment of CRP or fibrinogen. RESULTS: The addition of information on high-density lipoprotein cholesterol to a prognostic model for cardiovascular disease that included age, sex, smoking status, blood pressure, history of diabetes, and total cholesterol level increased the C-index, a measure of risk discrimination, by 0.0050. The further addition to this model of information on CRP or fibrinogen increased the C-index by 0.0039 and 0.0027, respectively (P<0.001), and yielded a net reclassification improvement of 1.52% and 0.83%, respectively, for the predicted 10-year risk categories of "low" (<10%), "intermediate" (10% to <20%), and "high" (≥20%) (P<0.02 for both comparisons). We estimated that among 100,000 adults 40 years of age or older, 15,025 persons would initially be classified as being at intermediate risk for a cardiovascular event if conventional risk factors alone were used to calculate risk. Assuming that statin therapy would be initiated in accordance with Adult Treatment Panel III guidelines (i.e., for persons with a predicted risk of ≥20% and for those with certain other risk factors, such as diabetes, irrespective of their 10-year predicted risk), additional targeted assessment of CRP or fibrinogen levels in the 13,199 remaining participants at intermediate risk could help prevent approximately 30 additional cardiovascular events over the course of 10 years. CONCLUSIONS: In a study of people without known cardiovascular disease, we estimated that under current treatment guidelines, assessment of the CRP or fibrinogen level in people at intermediate risk for a cardiovascular event could help prevent one additional event over a period of 10 years for every 400 to 500 people screened. (Funded by the British Heart Foundation and others.).