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

Overview and comparison of contemporary Society for Vascular Surgery, American Heart Association/American College of Cardiology, and European Society for Vascular Surgery guidelines for the management of patients with intermittent claudication

Intermittent claudication (IC) is a phenotype of peripheral artery disease that is characterized by pain in the lower extremity muscles during activity that is relieved by rest. Medical management, risk factor control, smoking cessation, and exercise therapy have historically been the mainstays of treatment for IC, but advances in endovascular technology have led to increasing use of peripheral vascular interventions in this patient population. There are meaningful differences in published society guidelines and appropriate use criteria relevant to the management of IC, especially regarding indications for peripheral vascular interventions. The current review aims to highlight similarities and differences between major society recommendations for the management of IC, and to discuss practice trends, disparities, and evidence gaps in the use of peripheral vascular interventions for IC in the context of existing guidelines.

Stem Cell Therapy in Critical Limb Ischemia

Critical limb ischemia (CLI), a serious outcome of peripheral artery disease, is frequently associated with morbid outcomes. The available treatment modalities do not provide satisfactory results, leading to marked morbidities such as joint contracture and amputations, resulting in a high economic burden. The peripheral vascular disease tends to cause more morbidity in patients with diabetes and atherosclerosis, given the pre-existing compromised perfusion of medium and small vessels in diabetic patients. With surgical procedures, the chance of vascular compromise further increases, inducing a significantly greater rate of amputation. Hence, the need for nonsurgical treatment modalities such as stem cell therapy (SCT), which promotes angiogenesis, is warranted. In CLI, SCT acts through neovascularization and the development of collateral arteries, which increases blood supply to the soft tissues of the ischemic limb, providing satisfactory outcomes. An electronic database search was performed in PubMed, SCOPUS, EMBASE, and ScienceDirect to identify published clinical trial data, research studies, and review articles on stem cell therapy in critical limb ischemia. The search resulted in a total of 2391 results. Duplicate articles screening resulted in 565 articles. In-depth screening of abstracts and research titles excluded 520 articles, yielding 45 articles suitable for full-text review. On review of full text, articles with overlapping and similar results were filtered, ending in 25 articles. SCT promotes arteriogenesis, and bone marrow-derived mesenchymal stromal cells produce significant effects like reduced morbidity, improved amputation-free survival (AFS ) rate, and improved distal perfusion even in "no-option" CLI patients. SCT is a promising treatment modality for CLI patients, even in those in whom endovascular and revascularization procedures are impossible. SCT assures a prolonged AFS rate, improved distal perfusion, improved walking distances, reduced amputation rates, and increased survival ratio, and is well-tolerated.

Clinical and Cardiovascular Profile in Patients With Peripheral Artery Disease

Background  Peripheral artery disease (PAD) is a vascular disorder leading to serious complications if not managed promptly. This study is conducted to analyze clinical and cardiovascular risk factors in PAD patients presenting at a tertiary care hospital and management strategies. Methodology This observational study was conducted at the Department of Cardiology, Mohamed Bin Khalifa Specialist Cardiac Centre. One hundred and twenty patients aged more than 35 years with PAD were included in the study. Data regarding age, gender, physical exam, cardiovascular risk profile, carotid disease, coronary artery disease, and treatment strategy were recorded on a pre-designed questionnaire by the researcher himself. The data were analyzed using IBM Corp. Released 2017. IBM SPSS Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp. Results The mean age of patients with PAD was 65.46±10.56 years. About 79.2% were hypertensive, 81.7% had hyperlipidemia, 83.3% had diabetes, 29.2% had renal insufficiency, and 38.3% were active smokers, respectively. In age ≥65 years, infra-popliteal PAD was significantly lower as compared to above-knee PAD (23.4% vs. 76.6%, p=0.002). In diabetic patients, the proportion of above-knee PAD was higher than below-knee PAD (60% vs. 40%, p=0.033). Conclusion Older age, diabetes, and carotid disease were significant predictors for peripheral artery disease, and these are significantly associated with above-the-knee peripheral artery disease.

Detecting Peripheral Arterial Disease in Primary Care: A Population Based Study

BACKGROUND

Peripheral arterial disease (PAD) can progress silently without any clinical symptoms. Ankle-brachial index (ABI) is the recommended method used in primary care. We aimed to determine the prevalence of PAD and its related risk factors in primary care.

METHODS

In this cross-sectional study, 250 participants aged ≥45 years were recruited randomly from the registered patients of family health center in a district of Izmir, Turkey. Patients' demographic data, PAD symptoms, and PAD risk factors were obtained. The PAD group consisted of patients with ABI levels <0.9; the non-compressible artery (NCA) group consisted of patients with ABI levels >1.3.

RESULTS

The prevalence of PAD was 17.6% (22.5% in women and 11.1% in men), while that of NCA was 15.2% (12.7% in women and 25.0% in men). About 27.3% and 54.5% of patients with PAD did not have claudication and problems with walking distance, respectively. Of the NCA patients, 15.8% had problems with walking distance and 39.5% had claudication. Regression analysis revealed two predictors of PAD (age ≥65 years: odds ratio [OR], 3.51; 95% confidence interval [CI], 1.65-7.47; claudication: OR, 3.41; 95% CI, 1.58-7.39) and three predictors of NCA (age <65 years: OR, 2.55; 95% CI, 1.01-6.45; male sex: OR, 2.40; 95% CI, 1.10-5.25; triglyceride [TG] >200 mg/dL: OR, 4.11; 95% CI, 1.58-10.67).

CONCLUSION

PAD had a prevalence of 17.6% and was associated with age ≥65 years and claudication. NCA had a prevalence of 15.2% and was associated with age <65 years, TG >200 mg/dL, and male sex.

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.

Blood Pressure Levels at the Time of Percutaneous Coronary Revascularization and Risk of Coronary In-Stent Restenosis

BACKGROUND

High blood pressure (BP) levels expose patients treated with percutaneous coronary interventions (PCI) to very high risk of 10-year cardiovascular morbidity and mortality.

OBJECTIVE

To investigate the role of BP levels at the time of PCI on the risk of in-stent restenosis (ISR).

METHODS

We retrospectively included 796 patients previously treated with PCI, who underwent repeated angiography for recurrent angina or reversible myocardial ischemia. Patients were stratified into either case (n = 354) and control (n = 442) groups in the presence or absence of ISR (defined as in-stent diameter stenosis ≥50%). BP levels were measured at the time of first and second procedures. Normal BP levels were defined for <140/90 mm Hg.

RESULTS

Patients with normal BP showed significantly higher ISR-free survival (Log-rank: 5.937; P = 0.015). Both systolic (HR (95% CI): 0.731 (0.590-0.906)) and systolic/diastolic BP (HR (95% CI): 0.757 (0.611-0.939)) were significantly and independently associated with lower risk of ISR at Cox-regression analysis, adjusted for potential confounding factors, including stent type and concomitant medications. Patients with ISR showed lower rates of normal systolic/diastolic BP values (166 (47%) vs. 254 (57%); P = 0.003) compared to controls. They also received higher stent number (1.40±0.74 vs. 1.24±0.51; P < 0.001) with higher stent length (24.3±15.6 vs. 21.7±13.9 mm; P = 0.012), and lower rate of drug-eluting stents (DESs) (210 (48%) vs. 139 (40%); P = 0.025) compared to controls.

CONCLUSIONS

Normal BP at the time of PCI is associated with nearly 24% risk reduction of ISR as evaluated in a new angiography in patients with coronary artery disease.

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.

Screening for Peripheral Arterial Disease and Carotid Artery Disease in Patients With Abdominal Aortic Aneurysm

Screening for concomitant atherosclerotic disease is important in cardiovascular risk reduction. This study assessed the prevalence of carotid artery disease (CAD) and peripheral arterial disease (PAD) in patients with known abdominal aortic aneurysms (AAAs). All patients with AAA attending the vascular laboratory between the January 1, 2007, and December 31, 2009, were eligible for a carotid ultrasound and measurement of ankle brachial indices. A total of 389 (305 males) patients were identified on the AAA surveillance program with a mean (±standard deviation) age of 76 (±8) years. The mean age of the males was 75.4 (±7.8) years, and the mean age of the females was 77 (±11) years. A total of 332 patients were assessed for CAD, and 101 (30.4%) of those were found to have significant disease. A total of 289 patients were assessed for PAD of which 131 (45.3%) were found to have PAD at rest, and 289 patients were assessed for both and 59 (20.4%) patients had significant CAD + PAD. Patients with AAAs are at high risk of other atherosclerotic disorders, and, therefore, they should receive intensive medical optimization.

The prevalence of peripheral arterial disease in middle-aged people with intellectual disabilities

Peripheral arterial disease (PAD) is a manifestation of atherosclerosis below the bifurcation of the abdominal aorta. PAD increases the risk of cardiovascular disease and associated mortality. Little is known about the prevalence of PAD in middle-aged persons with intellectual disabilities (ID). We determined the prevalence of PAD among people with ID aged 40-59 years. Independent associations between PAD and patient and care characteristics were explored. A multi-center cross-sectional observational study was conducted in four care providing agencies for people with ID in the Netherlands. We included 407 participants with mild to profound ID aged 40-59 years, receiving medical care from specialized ID physicians. The ankle-brachial index was used to diagnose PAD. The overall prevalence of PAD was 8.4% (95% CI=6.0-11.4%), with no significant differences between age groups 40-49 years (8.2%) and 50-59 years (8.5%). None of the participants had been diagnosed with PAD prior to this study and only one participant with PAD had PAD-related symptoms (1/34). Wheelchair dependence was independently associated with PAD (OR=5.43). Prevalence of PAD among people with ID is high, which is especially remarkable in age group 40-49 years. Physicians need to be aware of this high prevalence of PAD and the increased risk of cardiovascular disease in (young) people with ID.

Characteristics and long-term follow-up of participants with peripheral arterial disease during ALLHAT

BACKGROUND

Hypertension is a major risk factor for peripheral artery disease (PAD). Little is known about relative efficacy of antihypertensive treatments for preventing PAD.

OBJECTIVES

To compare, by randomized treatment groups, hospitalized or revascularized PAD rates and subsequent morbidity and mortality among participants in the Antihypertensive and Lipid-Lower Treatment to Prevent Heart Attack Trial (ALLHAT).

DESIGN

Randomized, double-blind, active-control trial in high-risk hypertensive participants.

PARTICIPANTS

Eight hundred thirty participants with specified secondary outcome of lower extremity PAD events during the randomized phase of ALLHAT.

INTERVENTIONS/EVENTS

In-trial PAD events were reported during ALLHAT (1994-2002). Post-trial mortality data through 2006 were obtained from administrative databases. Mean follow-up was 8.8 years.

MAIN MEASURES

Baseline characteristics and intermediate outcomes in three treatment groups, using the Kaplan-Meier method to calculate cumulative event rates and post-PAD mortality rates, Cox proportional hazards regression model for hazard ratios and 95 % confidence intervals, and multivariate Cox regression models to examine risk differences among treatment groups.

KEY RESULTS

Following adjustment for baseline characteristics, neither participants assigned to the calcium-channel antagonist amlodipine nor to the ACE-inhibitor lisinopril showed a difference in risk of clinically advanced PAD compared with those in the chlorthalidone arm (HR, 0.86; 95 % CI, 0.72-1.03 and HR, 0.98; 95 % CI, 0.83-1.17, respectively). Of the 830 participants with in-trial PAD events, 63 % died compared to 34 % of those without PAD; there were no significant treatment group differences for subsequent nonfatal myocardial infarction, coronary revascularizations, strokes, heart failure, or mortality.

CONCLUSIONS

Neither amlodipine nor lisinopril showed superiority over chlorthalidone in reducing clinically advanced PAD risk. These findings reinforce the compelling need for comparative outcome trials examining treatment of PAD in high-risk hypertensive patients. Once PAD develops, cardiovascular event and mortality risk is high, regardless of type of antihypertensive treatment.

Peripheral arterial disease in older people with intellectual disability in The Netherlands using the ankle-brachial index: results of the HA-ID study

Older people with an intellectual disability (ID) have been shown to have similar to increased cardiovascular risks as compared to the general population. Peripheral arterial disease (PAD), atherosclerosis distal from the aortic bifurcation, is associated with increased cardiovascular morbidity and mortality. The prevalence of PAD has not been investigated in this population. Therefore, the aim of the present study was to determine the prevalence of PAD in older people with ID in The Netherlands, the rate of prior diagnoses, and correlations with participant characteristics, and to compare the prevalence with PAD in the general Dutch population. 771 people aged 50 years and over participated in ankle-brachial index (ABI) measurement as part of a multi-centre cross-sectional study (HA-ID study). PAD was defined as an ABI<0.9. After excluding those, who met the exclusion criteria, 629 participants remained. PAD was present in 20.7% of the participants and 97% had not been diagnosed before. People with higher age, smokers and people who lived in central settings, walked with support and were more dependent in activities of daily living were more at risk of PAD. Prevalence of PAD is higher than in the general population (17.4% of 562 eligible participants with ID, as compared to 8.1% of 917 Dutch participants of the PANDORA study, a pan-European study into the prevalence of PAD) through all age groups. Because the high prevalence of PAD implies a serious health risk for older people with ID, we recommend that ankle-brachial index measurement is to be routinely performed as part of the cardiovascular risk management in this group.

An algorithmic approach to peripheral artery disease in hemophilia: extrapolation of management principles from noncoagulopathic patients

The development of peripheral artery disease (PAD), a marker for systemic atherosclerosis and ischemic risk, is an increasingly important concern in the aging hemophilia population. A growing body of data suggests that an absence or deficiency of factor VIII or factor IX may not protect against atherogenesis, implying that the prevalence of PAD in men with hemophilia (MWH) may be higher than previously believed. This article describes special considerations in PAD screening, risk-factor modification, and management in older MWH.

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 of peripheral arterial disease and related risk factors in Turkish elders

Background

It is known that prevalence of peripheral arterial disease being a widespread atherosclerotic vascular disease increases by age. On the other hand, no comprehensive study showing the prevalence of peripheral arterial disease in Turkish elders is seen. In this study, it is aimed to assess prevalence of peripheral arterial disease and related risk factors in Turkish elders in primary health center.

Methods

507 elderly staying at Narlidere Geriatric Care Center and Residential Home and accepting to participate in the study were included in the study. Epidemiological data for diagnosis of peripheral arterial disease, risk factors, findings of physical examination and ankle brachial index measurements were assessed in the study. Data were analyzed in terms of prevalence of peripheral arterial disease, age and gender relation and other cardiovascular risk factors.

Results

Of the participants, 317 (62.5%) were female. The mean age was 77.61 ± 6.93 years (62-102). The most wide-spread chronic diseases in elderly included hypertension, coronary artery disease, hyperlipidemia and Type 2 DM, respectively. On the other hand, only 7 (1.4%) elderly were diagnosed with peripheral arterial disease. The number of elderly ABI of whom was measured as < 0.90 and sent to cardiovascular surgery polyclinic with the diagnosis of peripheral arterial disease was assessed as 30 (5.9%). Intermittent claudication was seen in about half of these patients.

Conclusions

Peripheral arterial disease is expected to be seen prevailing in elderly. However, it was determined at very low rate before the study due to the fact that the disease cannot be diagnosed clinically especially in early-period. Peripheral arterial disease determined in the study is lower than expected as per the age group. This can be associated with practices of geriatrics nursing and family practice including continuous care to reduce cardiovascular risk factors of patients staying at the unit.