Prevalence of peripheral arterial disease in high-risk patients using ankle-brachial index in general practice: a cross-sectional study

Women Specific Characteristics and 1-Year Outcome Among Patients Hospitalized for Peripheral Artery Disease: A Monocentric Cohort Analysis in a Tertiary Center

Although women have lower age-standardized cardiovascular disease incidence, prevalence, and death-related rates than men, there are also reports indicating that women with cardiovascular disease receive less care, fewer investigations, and have poorer outcomes after a coronary event. The aims of this study were to compare the characteristics of men and women hospitalized for peripheral artery disease (PAD), their cardiovascular and limb outcomes, and their 1-year mortality. The study is a prospective registry collecting data about all consecutive patients hospitalized for PAD within the vascular department of the tertiary center Georges-Pompidou European Hospital (Paris, France). Patients were required to have one of three inclusion criteria: previous revascularization of the lower limb or any lower limb artery occlusion due to an atherosclerotic vascular disease or hemodynamic evidence of PAD. Exclusion criteria were patients with lower extremity arterial occlusion due to another cause. All patients were followed-up for at least 12 months after the initial hospitalization. Among the 235 patients included, there were 61 women (26%), older than men with a median age of 75.6 and 68.3 years, respectively. Main cardiovascular risk factors and comorbidities were similar for men and women except more former or current smokers [145 (83.4%) vs. 33 (54.1%)] and more history of coronary heart disease [42 (24.1%) vs. 7 (11.5%)] in men. Most patients [138 (58.8%)] had critical limb ischemia and 97 (41.3%) had claudication, with no difference for sex. After discharge, 218 patients received an antithrombotic therapy (93.2%), 195 a lipid-lowering drug (83.3%), 185 an angiotensin converting enzyme inhibitor or angiotensin-receptor blocker (78.9%), similarly between sex. At 1-year, overall mortality, major adverse cardiovascular events, major adverse limb events did not differ with 23 (13.2%), 11 (6.3%) and 32 (18.4%) in men, and 8 (13.1%), 3 (4.9%), 15 (24.6%) in women, respectively, despite the difference in age. Overall mortality, cardiovascular outcomes, limb revascularization or amputation did not differ between men and women, 1-year after hospitalization for PAD although the latter were older, less smoker and had less coronary artery disease. Due to the small size of this cohort, larger studies and future research are needed to better understand sex-specific mechanisms in the pathophysiology and natural history of PAD.

Progress in drug-delivery systems in cardiovascular applications: stents, balloons and nanoencapsulation

Drug-delivery systems in cardiovascular applications regularly include the use of drug-eluting stents and drug-coated balloons to ensure sufficient drug transfer and efficacy in the treatment of cardiovascular diseases. In addition to the delivery of antiproliferative drugs, the use of growth factors, genetic materials, hormones and signaling molecules has led to the development of different nanoencapsulation techniques for targeted drug delivery. The review will cover drug delivery and coating mechanisms in current drug-eluting stents and drug-coated balloons, novel innovations in drug-eluting stent technologies and drug encapsulation in nanocarriers for delivery in vascular diseases. Newer technologies and advances in nanoencapsulation techniques, such as the use of liposomes, nanogels and layer-by-layer coating to deliver therapeutics in the cardiovascular space, will be highlighted.

A systematic review and meta-analysis of risk factors for and incidence of 30-day readmission after revascularization for peripheral artery disease

OBJECTIVE

Readmission to the hospital after revascularization for peripheral artery disease (PAD) is frequently reported. No consensus exists as to the exact frequency and risk factors for readmission. This review aimed to determine the incidence of and risk factors for 30-day readmission after revascularization for PAD.

METHODS

PubMed/Medline (Ovid), Scopus, Web of Science, the Cochrane Library, and CINAHL were searched systematically from inception until May 20, 2018. Studies were eligible for inclusion if they included patients with diagnosed PAD undergoing revascularization and reported the readmission rate and a statistical evaluation of the association of at least one risk factor with readmission. Studies were excluded if data for other procedures could not be distinguished from revascularization. Two authors undertook study selection independently with the final inclusion decision resolved through consensus. The PRISMA and Meta-analyses of Observational Studies in Epidemiology guidelines were followed regarding data extraction and quality assessment, which was performed by two authors independently. Data were pooled using a random effects model.

RESULTS

The primary outcome was readmission within 30 days of revascularization. Fourteen publications reporting the outcomes of 526,008 patients were included. Reported readmission rates ranged from 10.9% to 30.0% with a mean of 16.4% (95% confidence interval [CI], 15.1%-17.9%). Meta-analyses suggested the following risk factors had a significant association with readmission: female sex (odds ratio [OR], 1.13; 95% CI, 1.05-1.21), black race (OR, 1.36; 95% CI, 1.28-1.46), dependent functional status (OR, 1.72; 95% CI, 1.43-2.06), critical limb ischemia (OR, 2.12; 95% CI, 1.72-2.62), emergency admission (OR, 1.75; 95% CI, 1.43-2.15), hypertension (OR, 1.39; 95% CI, 1.26-1.54), heart failure (OR, 1.82; 95% CI, 1.50-2.20), chronic pulmonary disease (OR, 1.19; 95% CI, 1.08-1.32), diabetes (OR, 1.47; 95% CI, 1.32-1.63), chronic kidney disease (OR, 1.93; 95% CI, 1.62-2.31), dialysis dependence (OR, 2.08; 95% CI, 1.75-2.48), smoking (OR, 0.83; 95% CI, 0.78-0.89), postoperative bleeding (OR, 1.70; 95% CI, 1.23-2.35), and postoperative sepsis (OR, 4.13; 95% CI, 2.02-8.47).

CONCLUSIONS

Approximately one in six patients undergoing revascularization for PAD are readmitted within 30 days of their procedure. This review identified multiple risk factors predisposing to readmission, which could potentially serve as a way to target interventions to reduce readmissions.

A Targeted Literature Review of the Disease Burden in Patients With Symptomatic Peripheral Artery Disease

Patients with peripheral artery disease (PAD) have an increased risk of cardiovascular (CV) and limb events, but the disease is frequently underdiagnosed and treatment options are limited. This review examines the disease burden of symptomatic PAD as well as key guideline recommendations. Publications were identified using the ProQuest portal to access the Medline, Medline In-Process, and Embase databases. Search terms for symptomatic PAD were combined with terms relevant to epidemiology, burden, treatment practice, and physiopathology. Articles in English published between January 2001 and September 2016 were screened according to the population, interventions, comparator, outcomes, and study design criteria. Relevant publications (n = 200) were identified. The reported incidence and prevalence of PAD varied depending on the definitions used and the study populations. Patients generally had a poor prognosis, with an increased risk of mortality, CV, and limb events and decreased quality of life. Guideline recommendations included ankle–brachial index measurements, exercise testing, and angiography for diagnosis and risk factor modification, antiplatelets, cilostazol, exercise therapy, or surgical interventions for treatment, depending on the patient profile. The clinical, humanistic, and economic burden of disease in patients with symptomatic PAD is substantial and needs to be reduced through improved PAD management.

Feasibility and Clinical Relevance of a Mobile Intervention Using TrackPAD to Support Supervised Exercise Therapy in Patients With Peripheral Arterial Disease: Study Protocol for a Randomized Controlled Pilot Trial

Background

Peripheral arterial disease (PAD) is a common and severe disease with a highly increased cardiovascular morbidity and mortality. Through the circulatory disorder and the linked undersupply of oxygen carriers in the lower limbs, the ongoing decrease of the pain-free walking distance occurs with a significant reduction in patients’ quality of life. Studies including activity monitoring for patients with PAD are rare and digital support to increase activity via mobile health technologies is mainly targeted at patients with cardiovascular disease in general. The special requirement of patients with PAD is the need to reach a certain pain level to improve the pain-free walking distance. Unfortunately, both poor adherence and availability of institutional resources are major problems in patient-centered care.

Objective

The objective of this trackPAD pilot study is to evaluate the feasibility of a mobile phone–based self tracking app to promote physical activity and supervised exercise therapy (SET) in particular. We also aim for a subsequent patient centered adjustment of the app prototype based on the results of the app evaluation and process evaluation.

Methods

This study was designed as a closed user group trial, with assessors blinded, and parallel group study with face-to-face components for assessment with a follow-up of 3 months. Patients with symptomatic PAD (Fontaine stage IIa or IIb) and possession of a mobile phone were eligible. Eligible participants were randomly assigned into study and control group, stratified by their distance covered in the 6-min walk test, using the software TENALEA. Participants randomized to the study group received usual care and the mobile intervention (trackPAD) for the follow-up period of 3 months, whereas participants randomized to the control group received only usual care. TrackPAD records the frequency and duration of training sessions and pain level using manual user input. Clinical outcome data were collected at the baseline and after 3 months via validated tools (6-min walk test, ankle-brachial index, and duplex ultrasound at the lower arteries) and self-reported quality of life. Usability and quality of the app was determined using the user version of the Mobile Application Rating Scale.

Results

The study enrolled 45 participants with symptomatic PAD (44% male). Of these participants, 21 (47%) were randomized to the study group and 24 (53%) were randomized to the control group. The distance walked in the 6-min walk test was comparable in both groups at baseline (study group: mean 368.1m [SD 77.6] vs control group: mean 394.6m [SD 100.6]).

Conclusions

This is the first trial to test a mobile intervention called trackPAD that was designed especially for patients with PAD. Its results will provide important insights in terms of feasibility, effectiveness, and patient preferences of an app-based mobile intervention supporting SET for the conservative treatment of PAD.

International Registered Report Identifier (IRRID)

DERR1-10.2196/13651

Association between 1p13 polymorphisms and peripheral arterial disease in a Chinese population with diabetes

AIMS/INTRODUCTION

Variants on chromosome 1p13 have been associated with coronary artery disease and acute myocardial infarction risk in different ethnic groups. The present study aimed to investigate the association between 1p13 polymorphisms and the development of peripheral artery disease (PAD) in a Chinese population with type 2 diabetes mellitus.

MATERIALS AND METHODS

1p13 polymorphisms, rs599839, rs646776 and rs12740374, were assessed in a cohort of 882 type 2 diabetes mellitus patients including 440 type 2 diabetes mellitus patients with PAD (DM + PAD group) and 442 patients without PAD (DM group). Genotyping was carried out using TaqMan assay.

RESULTS

Compared with the DM group, the frequencies of the minor G allele of both rs599839 and rs646776 and the minor T allele of rs12740374 decreased (P = 0.013, P = 0.019 and P = 0.005, respectively), and the frequencies of rs599839 AG + GG, rs646776 AG + GG and rs12740374 CT+TT genotypes were statistically significantly decreased as well (P = 0.017, P = 0.011 and P = 0.007, respectively) in the dominant model in the DM + PAD group than in the DM group. Multivariate unconditional logistic regression analyses adjusted for age, glycated hemoglobin, triglyceride, low-density lipoprotein cholesterol, smoking, hypertension, diabetes duration, coronary heart disease and cerebral infarction showed that the genotypic distribution of rs599839 AG + GG, rs646776 AG + GG and rs12740374 CT + TT remained statistically different between the DM and DM + PAD group (P = 0.014, P = 0.003 and P = 0.004, respectively). The frequencies of haplotype GGT were statistically significantly different between groups (P = 0.08).

CONCLUSIONS

The present study strongly supports that genotypes of rs599839, rs646776 and rs12740374 on 1p13 are protective factors for diabetic PAD in a Chinese population. Haplotype GGT generated by rs599839, rs646776 and rs12740374 might also decrease the risk of the disease.

Collagen-binding nanoparticles for extracellular anti-inflammatory peptide delivery decrease platelet activation, promote endothelial migration, and suppress inflammation

Peripheral artery disease is an atherosclerotic stenosis in the peripheral vasculature that is typically treated via percutaneous transluminal angioplasty. Deployment of the angioplasty balloon damages the endothelial layer, exposing the underlying collagen and allowing for the binding and activation of circulating platelets which initiate an inflammatory cascade leading to eventual restenosis. Here, we report on collagen-binding sulfated poly(N-isopropylacrylamide) nanoparticles that are able to target to the denuded endothelium. Once bound, these nanoparticles present a barrier that reduces cellular and platelet adhesion to the collagenous surface by 67% in whole blood and 59% in platelet-rich plasma under biologically relevant shear rates. In vitro studies indicate that the collagen-binding nanoparticles are able to load and release therapeutic quantities of anti-inflammatory peptides, with the particles reducing inflammation in endothelial and smooth muscle cells by 30% and 40% respectively. Once bound to collagen, the nanoparticles increased endothelial migration while avoiding uptake by smooth muscle cells, indicating that they may promote regeneration of the damaged endothelium while remaining anchored to the collagenous matrix and locally releasing anti-inflammatory peptides into the injured area. Combined, these collagen-binding nanoparticles have the potential to reduce inflammation, and the subsequent restenosis, while simultaneously promoting endothelial regeneration following balloon angioplasty.

STATEMENT OF SIGNIFICANCE

In this manuscript, we present our work on the development and characterization of a novel temperature sensitive collagen-binding nanoparticle system. We demonstrate that when bound to a collagenous matrix, the nanoparticles are able to promote endothelial migration while avoiding cellular uptake. We also show that the nanoparticles are able to reduce inflammation via the release of anti-inflammatory peptides which, when combined with its ability to inhibit platelet binding, could lead to reduced intimal hyperplasia following balloon angioplasty. The drug delivery platform presented represents a unique dual therapy biomaterial wherein the nanoparticle itself plays a crucial role in the system's overall therapeutic potential while simultaneously releasing anti-inflammatory peptides.

The diagnostic value of non-contrast enhanced quiescent interval single shot (QISS) magnetic resonance angiography at 3T for lower extremity peripheral arterial disease, in comparison to CT angiography

BACKGROUND

The high incidence of renal insufficiency in patients with Peripheral Arterial Disease raises the concern for nephrogenic systemic fibrosis (NSF) with respect to contrast enhanced MRA. The risk of NSF is eliminated with non-contrast enhanced magnetic resonance angiography. The purpose of the current study is to compare image quality and diagnostic performance of non-contrast enhanced Quiescent Interval Single Shot (QISS) magnetic resonance angiography at 3 T versus CT angiography for evaluation of lower extremity Peripheral Arterial Disease (PAD).

METHODS

32 consecutive patients (23 male, 9 female, age range 40-81 years, average age 61.97 years) with clinically suspected lower extremity PAD underwent QISS MRA and CTA. 19 of 32 patients underwent Digital Subtraction Angiography (DSA). Image quality of MRA was compared with CTA by two radiologists with 10 and 8 years' experience according to a 4-point scale. The Kappa test was used to determine the intermodality agreement between MRA and CTA in stenosis assessment, and interobserver agreement with each method. Sensitivity and specificity of CTA and MRA in detecting hemodynamically significant stenosis (≥50 %) were compared, with DSA serving as reference standard when available.

RESULTS

Image quality of QISS MRA was rated 3.70 ± 0.49 by reader 1, and 3.72 ± 0.47 by reader 2, significantly lower than that of CTA (3.80 ± 0.44 and 3.82 ± 0.42, P < 0.001 for both readers). Intermodality agreement between MRA and CTA was excellent for assessment of stenosis (Kappa = 0.923 ± 0.013 for reader 1, 0.930 ± 0.012 for reader 2). Interobserver agreement was 0.936 ± 0.012 for CTA and 0.935 ± 0.011 for MRA. For readers 1 and 2 respectively, the sensitivity of QISS was 94.25 and 93.26 % (versus 90.11 and 89.13 % for CTA, P > 0.05), and specificity of QISS was 96.70 and 97.75 % (versus 96.55 and 96.51 % for CTA, P > 0.05). For heavily calcified segments, sensitivity of QISS (95.83 and 95.83 %) was significantly higher than that of CTA (74.19 and 76.67 %, P < 0.05).

CONCLUSION

QISS is a reliable alternative to CTA for evaluation of lower extremity PAD, and may be suitable as a first-line screening examination in patients with contraindications to intravenous contrast administration.

Prevention of Collagen-Induced Platelet Binding and Activation by Thermosensitive Nanoparticles

Peripheral artery disease is an atherosclerotic occlusion in the peripheral vasculature that is typically treated via percutaneous transluminal angioplasty. Unfortunately, deployment of the angioplasty balloon damages the endothelial layer, exposing the underlying collagen and allowing for the binding and activation of circulating platelets, which initiate an inflammatory cascade leading to eventual restenosis. Here, we report on the development of poly(NIPAm-MBA-AMPS-AAc) nanoparticles that have a collagen I-binding peptide crosslinked to their surface allowing them to bind to exposed collagen. Once bound, these particles mask the exposed collagen from circulating platelets, effectively reducing collagen-mediated platelet activation. Using collagen I-coated plates, we demonstrate that these particles are able to bind to collagen at concentrations above 0.5 mg/mL. Once bound, these particles inhibit collagen-mediated platelet activation by over 60%. Using light scattering and zeta potential measurements, we investigated the potential of the nanoparticles as a drug delivery platform. We have verified that the collagen-binding nanoparticles retain the temperature sensitivity common to poly(NIPAm)-based nanoparticles while remaining colloidally stable in aqueous environments. We also demonstrate that they are able to passively load and release anti-inflammatory cell penetrating peptides. Combined, we have developed a collagen-binding nanoparticle that has dual therapy potential, preventing collagen-mediated platelet activation while delivering water-soluble therapeutics directly to the damaged area.

Impact of cardiovascular risk factors on severity of peripheral artery disease

OBJECTIVE

The development of peripheral artery disease is affected by the presence of cardiovascular risk factors. It is unclear, whether particular risk factors are leading to different clinical stages of peripheral artery disease. The aim of this retrospective cross-sectional study was to assess the association of cardiovascular risk factors with the presence of critical limb ischaemia.

METHODS

The study cohort was derived from a consecutive registry of patients undergoing endovascular therapy in a tertiary referral centre between January 2000 and April 2014. Patients undergoing first-time endovascular intervention for chronic peripheral artery disease of the lower extremities were included. Univariate and multivariate logistic regression models were used to assess the association of age, sex, diabetes mellitus, hypertension, dyslipidaemia, smoking, and renal insufficiency with critical limb ischaemia vs. intermittent claudication.

RESULTS

A total of 3406 patients were included in the study (mean age 71.7 ± 11.8 years, 2075 [61%] male). There was a significant association of age (OR 1.67, 95%-CI 1.53-1.82, p < 0.001), male gender (OR 1.23, 95%-CI 1.04-1.47, p = 0.016), diabetes (OR 1.99, 95%-CI 1.68-2.36, p < 0.001) and renal insufficiency (OR 1.62, 95%-CI 1.35-1.96, p < 0.001) with the likelihood of critical limb ischaemia. Smoking was associated with intermittent claudication rather than critical limb ischaemia (OR 0.78, 95%-CI 0.65-0.94, p = 0.010), while hypertension and dyslipidaemia did not show an association with critical limb ischaemia.

CONCLUSIONS

In peripheral artery disease patients undergoing first-time endovascular treatment, age, male gender, diabetes, and renal insufficiency were the strongest predictors for the presence of critical limb ischaemia.

Association between polyvascular atherosclerosis and estimated glomerular filtration rate in patients with ischaemic stroke: data analysis of the patients in the Chinese National Stroke Registry

OBJECTIVES

This study evaluated the prevalence of chronic kidney disease (CKD) in ischemic stroke (IS) patients with polyvascular disease (PolyVD) and analysed the relationship between PolyVD and estimated glomerular filtration rate (eGFR) in IS patients.

METHODS

Data from 9152 consecutive IS patients from the China National Stroke Registry were analysed. PolyVD was defined as patients with IS and coronary artery disease (CAD) and/or peripheral arterial disease (PAD). Chronic kidney disease was defined as eGFR < 60 mL/minute/1.73 m(2).The prevalence of CKD in IS patients with PolyVD was calculated. Logistic regression was used to estimate the correlation between PolyVD and eGFR between the monovascular group (IS alone) and the PolyVD group after adjusting for age, current or previous smoking, moderate or heavy drinking, body mass index, hypertension, dyslipidemia, diabetes mellitus, atrial fibrillation, previous stroke, and National Institutes of Health Stroke Scale scores.

RESULTS

PolyVD was observed in 1387 of 9152 patients (15.16%). Among these patients, 1351 (14.76%) had CAD, 56 (0.61%) had PAD, and 20 (0.22%) had CAD and PAD in addition to IS. The prevalence of CKD in IS patients with PolyVD and IS alone was 29.56 and 16.28%, respectively (P < 0.0001). The PolyVD group had a significantly higher risk of lower eGFR (OR: 1.414, 95% CI: 1.202-1.665, P < 0.0001) compared with patients with IS alone.

DISCUSSION

IS patients with PolyVD had a high prevalence of CKD, and PolyVD was independently associated with a low eGFR.

Association between the ankle-brachial index, intermittent claudication, and physical activity level: what is the influence on the functional capacity of patients with or at high risk of cardiovascular disease?

Background

Patients with or at high risk of cardiovascular disease have a poor functional capacity; however, the influence of association among intermittent claudication (IC), abnormal ankle–brachial index (ABI), and physical activity level on functional capacity of these patients has not been fully studied.

Objective

The primary objective of this study was to investigate the association between the ABI, IC, and physical activity level, and the influence of these variables on the functional capacity of patients with or at high risk of cardiovascular disease seen in a reference cardiology outpatient clinic in Southern Brazil. The secondary objective was to assess the prevalence of peripheral arterial disease (PAD) in this sample of patients.

Patients and methods

This was a prospective cross-sectional study in which 162 consecutive patients were evaluated and classified into three groups according to their ABI: normal ABI (n=104, values between 1.00 and 1.40); borderline PAD (n=23, values between 0.91 and 1.00); and patients with PAD (n=35, ≤0.90). The presence of IC was assessed using the Edinburgh Claudication Questionnaire. The level of physical activity was assessed by the short version of the International Physical Activity Questionnaire (IPAQ) and functional capacity was assessed by the 6-minute walk distance (6MWD).

Results

The prevalence of PAD was 21.6% in the total sample. The 6MWD showed strong correlation with the absence of IC (r=0.785; P<0.001), moderate correlation with age (r=−0.347; P<0.001), and weak correlations with IPAQ scores (r=0.164; P=0.038) and ABI (r=0.216; P=0.006). Age, ABI, and absence of IC were independently associated with the outcome (P=0.001, P=0.001, and P=0.028, respectively).

Conclusion

The current study demonstrates that 6MWD is associated with IPAQ scores, ABI, and absence of IC. Age, ABI and absence of IC were independently associated with functional capacity in patients with or at high risk of cardiovascular disease.

Relative value of the Ankle-Brachial Index of intermittent claudication

INTRODUCTION

The Ankle-Brachial Index (ABI) makes it possible to identify patients with peripheral artery disease (PAD). Intermittent claudication (IC) is the first major symptom of PAD, although many patients with an ABI ≤ 0.9 do not exhibit IC, and the range of ABI among those who do have IC is very variable. This study evaluates the correlation between ABI and the perception (symptomatology) of claudicant patients.

MATERIAL AND METHODS

An observational, cross-sectional and multicentre, study of 920 patients with IC. Clinical history, ABI, Walking Impairment Questionnaire (WIQ) and European Quality of Life Questionnaire (EQ-5D) were recorded. Associations were analysed using Spearman's correlation coefficient.

RESULTS

The mean ABI of the series was 0.63 (SD = 0.19). The mean WIQ-distance was 34.07 (SD = 26.77), values being smaller for lower ABI values (r = 0.343, p < 0.001). The mean EQ-5D score of the series was 0.58 (SD = 0.21), also showing lower values as the ABI decreased (r = 0.278, p < 0.001). The correlations of WIQ and EQ-5D with ABI were statistically significant in both cases, but always less than 0.400 (between 0.278 and 0.343).

CONCLUSIONS

The correlations of ABI with the questionnaires of walking capacity and quality of life are weak. For this reason, although in clinical practice the ABI of CI patients is commonly measured, decisions should not be taken during the development of IC exclusively on the basis of the ABI.

Oxidative status imbalance in patients with metabolic syndrome: role of the myeloperoxidase/hydrogen peroxide axis

The present study evaluated the cardiometabolic and redox balance profiles in patients with Metabolic Syndrome compared to apparently healthy individuals, and the participation of the myeloperoxidase/hydrogen peroxide axis in systemic lipid peroxidation. Twenty-four patients with Metabolic Syndrome and eighteen controls underwent a full clinical assessment. Venous blood samples were collected for general biochemical dosages, as well as for the oxidative stress analyses (superoxide dismutase, catalase, and arginase activities; and lipid peroxidation, myeloperoxidase activity, nitrite, and hydrogen peroxide concentrations in plasma). Arterial stiffness was assessed by radial artery applanation tonometry. Plasma lipid peroxidation, erythrocyte superoxide dismutase activity, myeloperoxidase activity, and hydrogen peroxide concentrations were shown to be increased in Metabolic Syndrome patients, without significant differences for the other enzymes, plasma nitrite concentrations, and arterial stiffness. Linear regression analysis revealed a positive and significant correlation between lipid peroxidation and myeloperoxidase and also between this enzyme and hydrogen peroxide. In contrast, such correlation was not observed between lipid peroxidation and hydrogen peroxide. In summary, Metabolic Syndrome patients exhibited evident systemic redox imbalance compared to controls, with the possible participation of the myeloperoxidase/hydrogen peroxide axis as a contributor in lipid peroxidation.

Methods of symptom evaluation and their impact on peripheral artery disease (PAD) symptom prevalence: a review

Peripheral artery disease (PAD) is a common progressive atherosclerotic occlusive disease that causes insufficient blood flow to the lower extremities. The symptom that health care professionals most often associate with PAD is claudication. However, patient reporting of claudication is highly variable. A structured literature review was conducted to evaluate how PAD symptoms are identified, defined, and categorized. This review focuses on the development and performance characteristics of PAD symptom questionnaires and the identification of a spectrum of leg symptoms beyond classic claudication. Additionally, potential confounders of PAD symptom reporting and strategies for a more comprehensive assessment of PAD symptoms are discussed. Overall, there is a lack of consistency in the utilization of PAD claudication questionnaires which impacts PAD symptom reporting and categorization. Based on this review, atypical symptoms are commonly reported, but poorly understood. Additional research is needed to gain a better understanding of the presentation of atypical symptoms, as well as the role of age, gender, race, and comorbid conditions on the symptom experience of patients with PAD.

[Prevalence and risk factors of peripheral arterial disease in an outpatient screening campaign]

BACKGROUND

Peripheral arterial disease (PAD) is an important predictor of cardiovascular disease with major medico-economic consequences. However, systematic screening of asymptomatic patients free from history of cardiovascular disease is debated.

OBJECTIVE

Determining the prevalence, risk factors for PAD in a population of outpatients at intermediate or high-risk of cardiovascular disease, free from history of cardiovascular disease to assess the potential impact of PAD screening in such groups of patients.

METHODS

Multicenter 1-day screening program of PAD conducted from 2008 to 2010 in a population defined by diabetes plus age greater than 50 years, positive active smoking status, or age greater than 70 years. PAD was defined as an ankle-brachial index (ABI) less than 0.9 measured as follows: lowest systolic ankle pressure divided by highest systolic arm pressure.

RESULTS

Ten thousand six hundred and fourteen patients fulfilled study inclusion criteria: 16.7% (n = 1774) exhibited an ABI less than 0.9 and 3.8% (n = 407) an ABI less than 0.7. ABI greater than 1.3 was found in 7.7% of patients (n = 818). Age greater than 70 years, male gender, active smoking status, hypertension and diabetes (treated) were independent risk factors for PAD.

CONCLUSION

Primary prevention outpatient screening of a population with intermediate or high cardiovascular risk can identify numerous patients with PAD. The medical impact in terms of cardiovascular mortality and morbidity of such a screening needs to be assessed.

Prevalence of low ankle brachial index and its association with pulse pressure in an elderly Chinese population: a cross-sectional study

Background

We investigated the prevalence of low ankle brachial index (ABI) and the association of low ABI with pulse pressure among elderly community residents in China.

Methods

This population-based cross-sectional study was conducted in Beijing and recruited 2982 participants who were aged 60 years or older in 2007. Low ABI was defined as an ABI value less than 0.9 in either leg. Participants with or without stroke or coronary heart disease (CHD) were analyzed separately. The association between pulse pressure and low ABI was examined by using multiple logistic regression models.

Results

The prevalence of low ABI was 5.65% (4.24% among men and 6.52% among women; P = 0.0221) among participants without stroke or CHD and 10.91% (13.07% among men and 9.49% among women; P = 0.1328) among those with stroke or CHD. After adjusting for confounders, the odds ratio (95% CI) for each 5-mm Hg increase in pulse pressure was 1.19 (1.07, 1.33) and 1.10 (1.02, 1.20) for men and women, respectively, among participants without stroke or CHD and 1.17 (1.03, 1.34) and 1.15 (1.02, 1.30) for men and women with stroke or CHD. When pulse pressure was classified into quartiles and the lowest quartile was used as reference, the association between pulse pressure and low ABI remained positive in men and women.

Conclusions

Low ABI was prevalent among elderly Chinese, and pulse pressure was positively associated with low ABI.

Reliability of Doppler and stethoscope methods of determining systolic blood pressures: considerations for calculating an ankle-brachial index

PURPOSE

The purposes of this study were to: (1) identify the interrater and intrarater reliability of systolic blood pressures using a stethoscope and Doppler to determine an ankle-brachial index (ABI), and (2) to determine the correlation between the 2 methods.

BACKGROUND

Peripheral arterial disease (PAD) affects approximately 8 to 12 million people in the United States, and nearly half of those with this disease are asymptomatic. Early detection and prompt treatment of PAD will improve health outcomes. It is important that clinicians perform tests that determine the presence of PAD.

METHOD

Two individual raters trained in ABI procedure measured the systolic blood pressures of 20 individuals' upper and lower extremities. Standard ABI measurement protocols were observed. Raters individually recorded the systolic blood pressures of each extremity using a stethoscope and a Doppler, for a total of 640 independent measures.

RESULTS

Interrater reliability of Doppler measurements to determine SBP at the ankle was very strong (intraclass correlation coefficient [ICC], 0.93-0.99) compared to moderate to strong reliability using a stethoscope (ICC, 0.64-0.87). Agreement between the 2 devices to determine SBP was moderate to very weak (ICC, 0.13-0.61). Comparisons of the use of Doppler and stethoscope to determine ABI showed weak to very weak intrarater correlation (ICC, 0.17-0.35). Linear regression analysis of the 2 methods to determine ABI showed positive but weak to very weak correlations (r2 = .013, P = .184).

CONCLUSIONS

A Doppler ultrasound is recommended over a stethoscope for accuracy in systolic pressure readings for ABI measurements.

The PANDORA study: peripheral arterial disease in patients with non-high cardiovascular risk

Few studies are available with sufficient sample size to accurately describe the prevalence of low ankle-brachial index (ABI) in patients at 'non-high' cardiovascular (CV) risk. The aim of this study was to evaluate the prevalence of asymptomatic peripheral arterial disease (PAD), as determined by using ABI, in this patient population. A non-interventional, cross-sectional, pan-European study was conducted in patients with ≥1 CV risk factor in addition to age, evaluating the prevalence of asymptomatic PAD (ABI ≤ 0.90). Secondary objectives included assessing the prevalence and treatment of CV risk factors. Patients were consecutively recruited during scheduled visits to the physician's office, or were randomly selected by the physician from a list of eligible patients. Patients with diabetes were excluded as this condition was deemed to be a secondary prevention risk. 10,287 patients were enrolled (9,816 evaluable: mean age 64.3 years; 53.5% male). Prevalence of asymptomatic PAD was 17.8% (99% CI 16.84-18.83). Factors significantly associated with asymptomatic PAD included hypertension, age, alcohol intake, family history of coronary heart disease, low levels of high-density lipoprotein-cholesterol, and smoking (p < 0.0001). Patients treated with statins were significantly less likely to have asymptomatic PAD than those who were not (odds ratio 0.62; 95% CI 0.50-0.76; p < 0.0001). Asymptomatic PAD was highly prevalent in patients with non-high CV risk, the majority of whom would not typically be candidates for ABI assessment. These patients should be carefully screened, and ABI measured, so that therapeutic interventions known to diminish their increased CV risk may be offered.

Prevalence of peripheral arterial disease in subjects with moderate cardiovascular risk: Italian results from the PANDORA study Data from PANDORA (Prevalence of peripheral Arterial disease in subjects with moderate CVD risk, with No overt vascular Diseases nor Diabetes mellitus)

BACKGROUND

The PANDORA study has recently examined the prevalence of low ankle brachial index (ABI) in subjects with moderate risk of cardiovascular disease. This sub-analysis of the PANDORA study examines the prevalence of asymptomatic peripheral arterial disease (PAD), as determined by ABI, in Italian subjects presenting with moderate cardiovascular risk, in the absence of diabetes or overt vascular disease.

METHODS

PANDORA is a non-interventional, cross-sectional study that was performed in 6 European countries, involving subjects with at least one cardiovascular (CV) risk factor. The primary objective was to evaluate the prevalence of asymptomatic PAD using ABI. For this post-hoc sub-analysis, data were extracted for subjects enrolled in Italy, comprising 51.5% (n = 5298) of subjects from the original PANDORA study. Secondary objectives were to establish the prevalence and treatment of CV risk factors.

RESULTS

The mean age was 63.9 years and 22.9% (95% CI 21.7-24.0) of subjects presented with asymptomatic PAD. A range of risk factors comprising smoking, hypertension, low HDL-cholesterol, family history of coronary heart disease and habit of moderate-high alcohol intake were significantly associated with asymptomatic PAD (p < 0.0001). Statin treatment had the lowest incidence in Italian subjects. Furthermore, patients treated with statins were significantly less likely to have asymptomatic PAD than those who were not (p = 0.0001).

CONCLUSIONS

Asymptomatic PAD was highly prevalent in Italian subjects, the majority of whom were not candidates for ABI assessment according to current guidelines. Findings from this study suggest that these patients should be carefully examined in clinical practice and ABI measured so that therapeutic interventions known to decrease their CV risk may be offered.

Prevalence and clinical profile and management of peripheral arterial disease in elderly patients with diabetes

INTRODUCTION

Peripheral arterial disease (PAD) increases with age and diabetes. The aim of this study was to assess the prevalence of PAD in an elderly population with diabetes.

METHODS

This multicenter and cross-sectional study included patients >70 years, with an established diagnosis of diabetes. PAD was defined as those patients with a history of revascularization or amputation due to ischemia, or a pathological ankle-brachial index (ABI). Adequate blood pressure (BP), LDL cholesterol and HbA1c control were considered as <130/80 mm Hg, <100 mg⁄dL and <7.0%, respectively.

RESULTS

A total of 1462 patients were included. The most frequent cardiovascular risk factor and cardiovascular disease were hypertension (80.37%) and PAD (60.60% overall; 83.2% of those assisted by vascular surgeons vs 31.9% of those attended by other medical specialists; p<0.001), respectively. However, when ABI was measured, 70.99% of the study population had PAD (80.2% of those assisted by vascular surgeons vs 59.6% of those attended by other medical specialists; p<0.001). The predictors for a pathological ABI included male gender, smoking, dyslipidemia, family history of premature cardiovascular disease, sedentary lifestyle, diabetic-related complications, heart and cerebrovascular diseases. Although risk factors control was very poor, it was even lower in patients with PAD.

CONCLUSIONS

The prevalence of PAD is high in diabetic elderly patients. The concomitance with other risk factors and cardiovascular diseases was very high. The ABI allowed increasing the diagnosis of PAD.

To screen or not to screen for peripheral arterial disease in subjects aged 80 and over in primary health care: a cross-sectional analysis from the BELFRAIL study

BACKGROUND

Peripheral arterial disease (PAD) is common in older people. An ankle-brachial index (ABI) < 0.9 can be used as an indicator of PAD. Patients with low ABI have increased mortality and a higher risk of serious cardiovascular morbidity. However, because 80% of the patients are asymptomatic, PAD remains unrecognised in a large group of patients. The aims of this study were 1) to examine the prevalence of reduced ABI in subjects aged 80 and over, 2) to determine the diagnostic accuracy of the medical history and clinical examination for reduced ABI and 3) to investigate the difference in functioning and physical activity between patients with and without reduced ABI.

METHODS

A cross-sectional study embedded within the BELFRAIL study. A general practitioner (GP) centre, located in Hoeilaart, Belgium, recruited 239 patients aged 80 or older. Only three criteria for exclusion were used: urgent medical need, palliative situation and known serious dementia. The GP recorded the medical history and performed a clinical examination. The clinical research assistant performed an extensive examination including Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS-15), Activities of Daily Living (ADL), Tinetti test and the LASA Physical Activity Questionnaire (LAPAQ). ABI was measured using an automatic oscillometric appliance.

RESULTS

In 40% of patients, a reduced ABI was found. Cardiovascular risk factors were unable to identify patients with low ABI. A negative correlation was found between the number of cardiovascular morbidities and ABI. Cardiovascular morbidity had a sensitivity of 65.7% (95% CI 53.4-76.7) and a specificity of 48.6% (95% CI 38.7-58.5). Palpation of the peripheral arteries showed the highest negative predictive value (77.7% (95% CI 71.8-82.9)). The LAPAQ score was significantly lower in the group with reduced ABI.

CONCLUSION

The prevalence of PAD is very high in patients aged 80 and over in general practice. The clinical examination, cardiovascular risk factors and the presence of cardiovascular morbidity were not able to identify patients with a low ABI. A screening strategy for PAD by determining ABI could be considered if effective interventions for those aged 80 and over with a low ABI become available through future research.

Ankle brachial index screening in asymptomatic older adults

BACKGROUND

Screening for peripheral arterial disease (PAD) by measuring ankle brachial index (ABI) in asymptomatic older adults is currently recommended to improve cardiovascular disease risk assessment and establish early treatment, but it is not clear if the strategy is useful in all populations. We examined the prevalence and independent predictors of an abnormal ABI (<0.90), in an asymptomatic sample of 1,017 adults, 60 to 69 years old, enrolled in the ADVANCE study.

METHODS

Baseline data collected between December 2001 and January 2004 among the healthy older controls enrolled in ADVANCE was examined. Frequency distributions and prevalence estimates of an abnormal ABI were calculated, using both standard and modified definitions of ABI. Stepwise logistic regression was used to examine independent predictors of ABI <0.90. Signal detection analysis using recursive partitioning was employed to explore potential demographic and clinical variables related to ABI <0.90.

RESULTS

The prevalence of ABI <0.90 was 2% when using the standard definition and 5% when using a modified definition. ABI prevalence did not differ by gender (P > .05). Compared with subjects who had a normal ABI (0.90-1.39), subjects with an ABI <0.90 were more likely to currently smoke, be physically inactive, have a coronary artery calcium score >10, and an FRS >20% (P ≤ .02). Independent predictors of ABI <0.90 when using the standard definition included currently smoking, physical inactivity, and body mass index >30 (all P values ≤.03), and when using the modified definition included currently smoking, physical inactivity, and hypertension (all P values ≤.04). Currently, smoking was the only significant variable for ABI <0.90 derived through recursive partitioning (P = .02), and indicated that prevalence of ABI <0.90 was 1.5% for nonsmokers, while it was 6.6% for current smokers.

CONCLUSIONS

ABI screening in generally healthy individuals 60 to 69 years old may result in lower prevalence rates of a positive result than estimates based on studies in clinical populations. The modified definition for calculating ABI captured more asymptomatic adults with suspected peripheral arterial disease. More evaluation of the appropriate role of ABI screening in unselected populations is needed before routine screening is implemented.

Ankle brachial index screening for occult vascular disease is not useful in HIV-positive patients

Metabolic complications common to the HIV-positive population may increase the risk for cardiovascular disease. Asymptomatic peripheral arterial disease (PAD) is associated with increased cardiovascular risk. The ankle-brachial pressure index (ABI) is a screening tool commonly used for the detection of asymptomatic PAD. The prevalence of asymptomatic PAD based on ABI in HIV-positive patients is unknown. This study was cross-sectional in design and assessed PAD by measuring the systolic ABI as determined by a handheld 8-MHz Doppler probe with the patient at rest in a supine position. A brief medical history including pertinent risk factors was obtained. One hundred and sixty-seven HIV-positive patients were evaluated (97.6% male; mean age 52.0 years; 31.2% current smokers, 29.4% former smokers, 26.3% diabetes mellitus). Asymptomatic PAD (ABI < or = 0.9) was found in four patients (2.4%, 95% CI: 0.3-4.5%). Smoking was a significant predictor of PAD. Patients with a positive test for PAD had at least two major risk factors for the disease including smoking, a history of disease in another vascular bed, dyslipidemia, diabetes, and hypertension. All patients with a positive test for PAD had a high risk (>20%) for cardiovascular disease according to the Framingham risk score. Three of the four patients with positive tests had previously diagnosed vascular disease (CAD, stroke). Three patients presenting with PAD were evaluated and all had a positive ABI. The prevalence of PAD compared to previous studies on PAD in HIV was low and identified only those patients with high cardiovascular risk based on other features. ABI was not useful in detecting occult vascular disease in HIV-positive patients and offers no additional information to that derived from cardiovascular risk stratification.

Influence of polyvascular disease on cardiovascular event rates. Insights from the REACH Registry

Cardiovascular event rates have been shown to increase substantially with the number of symptomatic disease locations. We sought to assess the risk profile, management and subsequent event rates of polyvascular disease patients. Consecutive outpatients were assessed for atherosclerotic risk factors and medications in the REACH Registry. A total of 19,117 symptomatic patients in Europe completed a 2-year follow-up: 77.2% with single arterial bed disease (coronary artery or cerebrovascular or peripheral arterial disease) and 22.8% with polyvascular disease (≥ 1 disease location). Polyvascular disease patients were older (68.5 ± 9.4 vs 66.3 ± 9.9 years, p < 0.0001), more often current or former smokers (64.9% vs 58.7%, p < 0.0001), and more often suffered from hypertension (59.5% vs 46.6%, p < 0.0001) and diabetes (34.5% vs 25.9%, p < 0.0001) than single arterial bed disease patients. Despite more intense medical therapy, risk factors (smoking, hypertension, low fasting glucose, and low fasting total cholesterol) were less often controlled in polyvascular disease patients. This was associated with substantially more events over 2 years compared with single arterial bed disease patients (cMACCE [cardiovascular death/non-fatal stroke/non-fatal MI] odds ratio, 1.63 [95% CI, 1.45—1.83], p < 0.0001). In conclusion, polyvascular disease patients have more cardiovascular risk factors, and the prognosis for these patients is significantly worse than for patients with single arterial bed disease. This suggests a need to improve detection and consequent medical treatment of polyvascular disease.

Prevalence of peripheral arterial disease in patients at non-high cardiovascular risk. Rationale and design of the PANDORA study

BACKGROUND

Lower extremity peripheral arterial disease (PAD) is a marker of widespread atherosclerosis. Individuals with PAD, most of whom do not show typical PAD symptoms ('asymptomatic' patients), are at increased risk of cardiovascular ischaemic events. American College of Cardiology/American Heart Association guidelines recommend that individuals with asymptomatic lower extremity PAD should be identified by measurement of ankle-brachial index (ABI). However, despite its associated risk, PAD remains under-recognised by clinicians and the general population and office-based ABI detection is still poorly-known and under-used in clinical practice. The Prevalence of peripheral Arterial disease in patients with a non-high cardiovascular disease risk, with No overt vascular Diseases nOR diAbetes mellitus (PANDORA) study has a primary aim of assessing the prevalence of lower extremity PAD through ABI measurement, in patients at non-high cardiovascular risk, with no overt cardiovascular diseases (including symptomatic PAD), or diabetes mellitus. Secondary objectives include documenting the prevalence and treatment of cardiovascular risk factors and the characteristics of both patients and physicians as possible determinants for PAD under-diagnosis.

METHODS/DESIGN

PANDORA is a non-interventional, cross-sectional, pan-European study. It includes approximately 1,000 primary care participating sites, across six European countries (Belgium, France, Greece, Italy, The Netherlands, Switzerland). Investigator and patient questionnaires will be used to collect both right and left ABI values at rest, presence of cardiovascular disease risk factors, current pharmacological treatment, and determinants for PAD under-diagnosis.

DISCUSSION

The PANDORA study will provide important data to estimate the prevalence of asymptomatic PAD in a population otherwise classified at low or intermediate risk on the basis of current risk scores in a primary care setting.

TRIAL REGISTRATION NUMBER

Clinical Trials.gov Identifier: NCT00689377.

A review of simple, non-invasive means of assessing peripheral arterial disease and implications for medical management

Abstract Atherosclerotic peripheral arterial disease (PAD) is highly prevalent in the elderly and subjects with atherosclerotic risk factors such as smoking, diabetes mellitus, hypertension, and hyperlipidemia. Importantly, PAD is rarely an isolated condition, but rather a manifestation of systemic atherosclerosis. Hence, there is often coexisting disease in the coronary and cerebral arteries and, consequently, an increased risk of myocardial infarction and stroke. Intermittent claudication is the classic symptom of PAD, yet up to 50% of patients are asymptomatic. Despite the availability of reliable, non-invasive screening tests, PAD is largely underdiagnosed and undertreated, mostly due to the paucity of symptoms and underutilization of screening tools. The ankle-brachial index (ABI), a simple, rapid, and inexpensive diagnostic tool, holds much prognostic value for PAD diagnosis and is ideal for implementation in the primary care physician's office. The early detection of PAD with ABI screening and subsequent medical management represents a critical opportunity to prevent considerable vascular morbidity and mortality. The management of PAD must address claudication symptoms (with cilostazol or pentoxifylline, or in severe cases endovascular or surgical revascularization) and modifiable atherosclerotic risk factors (with an aggressive global risk-reduction regimen involving lifestyle modifications, exercise, smoking cessation, and antiplatelet, lipid-lowering, and antihypertensive therapy).