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Peripheral arterial disease (PAD) is a group of syndromes characterized by chronic and progressive atherosclerosis with a high burden of physical disability and cardiovascular morbidity and mortality. Recruiting patients for clinical research is therefore challenging. In this article, we describe and evaluate our methods for recruiting participants for a cross-sectional feasibility study of PAD, nutritional status, and body composition. We used convenience and purposive sampling approaches to identify potential participants. Between May 2012 and April 2013, 1,446 patients were identified, and 165 patients (11.4%) responded to recruitment requests. The final enrollment was 64 participants (64/1,446; 4.4%), and four subjects (6.3%) subsequently withdrew from the study. Recruiting PAD patients presents a variety of challenges, due largely to the burdens of living with coexistent illnesses, and patients' reluctance or inability to travel for research. In this article, we delineate suggestions for improving the efficacy of recruitment methods in future PAD studies. [ABSTRACT FROM AUTHOR]

In patients with peripheral artery disease (PAD), statins may improve the symptoms of claudication. The Intermittent Claudication Proof of Principle (ICPOP) study tested the hypothesis that the combination of extended release niacin plus lovastatin would improve exercise performance in patients with PAD and claudication compared with a diet intervention. A phase 3 double-blind, parallel-group, multi-center, 28-week multi-national study evaluated subjects with a history of claudication who had an ankle-brachial index (ABI) ≤ 0.90, a reproducible peak treadmill walking time (PWT) of 1-20 minutes, and a low-density lipoprotein (LDL)-cholesterol level < 160 mg/dl (< 4.1 mmol/l). Subjects were randomly assigned to low-dose niacin 1000 mg plus lovastatin 40 mg (low niacin-statin), high-dose niacin 2000 mg plus lovastatin 40 mg (high niacin-statin), or diet intervention (diet). The co-primary efficacy endpoint of percent change in PWT and claudication onset time (COT) at 28 weeks was assessed using a graded treadmill protocol. At completion, 385 subjects were analyzed for safety and 370 subjects were analyzed for efficacy. The primary efficacy analysis showed no statistical significance for overall treatment effect at week 28 for the co-primary endpoint of PWT and COT. The PWT component of the primary endpoint increased 26.5% on diet, 37.8% on high niacin-statin (p = 0.137) and 38.6% on low niacin-statin (p = 0.096). Flushing as the most common event leading to discontinuation and treatment was associated with increases in liver enzymes, fasting blood glucose concentration and a decrease in platelet count. [ABSTRACT FROM AUTHOR]

Lower extremity peripheral arterial disease (PAD) is prevalent in the Medicare population and is associated with high rates of myocardial infarction, stroke, amputation, and death. Nevertheless, national health expenditures for PAD are not known. We hypothesized that PAD-related costs are high, increase with age, and that treatment rates would be less than known PAD prevalence. The objective was to determine national health care expenditures for PAD in the United States. PAD-related treatment costs were calculated in the elderly, non-disabled Medicare population. The cost analysis relied on the 5% control population for the linked SEER- Medicare data and Medicare claims for the calendar year 2001, identifying PAD cases based on diagnosis and procedure codes. Costs were aggregated separately for inpatient and outpatient treatment and estimates adjusted to reflect the Medicare population. A total of $4.37 billion was spent on PAD-related treatment and 88% of expenditures were for inpatient care. Medicare program outlays totaled $3.87 billion, while enrollees (or their supplemental insurance) spent the remaining $500 million. In total, 6.8% of the elderly Medicare population received treatment for PAD. Treatment increased with age at rates of 4.5%, 7.5%, and 11.8% for individuals aged 65-74, 75-84, and >85 years, respectively. PAD-related costs accounted for approximately 13% of all Medicare Part A and B expenditures for the PAD-treated cohort, and 2.3% of total Medicare Part A and B expenditures. In conclusion, US national PAD-related costs are high, associated with inpatient care, and increase with age. PAD is treated at rates lower than the known PAD prevalence as only approximately one-third of the population with known PAD had detectable PAD-related health care costs in our analysis. The potential impact of earlier PAD detection and use of outpatient preventive strategies on total national PAD health care costs is unknown. [ABSTRACT FROM AUTHOR]

Peripheral arterial disease (PAD) is associated with significant morbidity and mortality, and yet remains under-recognized and under-treated. Atherosclerosis is the most common cause of lower extremity PAD and pharmacological interventions that alter this central patho- genic role of atherosclerosis may alter the natural history of PAD. There is growing evidence that the renin-angiotensin system (RAS) is a signi cant mediator of this disease process and that treatment with angiotensin-converting enzyme (ACE) inhibitors is associated with vasculopro- tective effects that are independent of the antihypertensive properties of these agents. Numerous lines of evidence suggest that ACE inhibitors directly inhibit the atherosclerotic process and improve vascular endothelial function. In patients with PAD, ACE inhibitors have been shown to improve peripheral circulation as measured by peripheral arterial blood pressure and by increases in peripheral blood flow. Preliminary evidence suggests that ACE inhibitors might improve clinical symptoms in patients with PAD. Recent evidence has confirmed that ACE inhibition is associated with a decrease in morbidity and mortality in patients with arterial disease without left ventricular dysfunction; this benefit was at least as great for the subset of patients with PAD. Overall, these data support a significant role for the RAS in the pathogenesis of all atherosclerotic diseases (including PAD) and suggest that the benefit is independent of the blood pressure lowering properties of these agents. These studies suggest that ACE inhibitor therapy should be considered in the routine management of individuals with PAD, regardless of whether they have hypertension or left ventricular dysfunction. [ABSTRACT FROM AUTHOR]

Atherosclerosis is a form of arterial disease that manifests in the coronary circulation as coronary artery disease (CAD), in the carotid arteries as cerebrovascular disease, and in the aorta and lower extremity arteries as peripheral arterial disease (PAD). The systemic nature of the disease is reflected in the fact that individuals with PAD or carotid artery disease are more likely to have CAD than those without. Since individuals with PAD are at markedly increased risk of cardiovascular ischemic events, early identification of this population and more aggressive medical interventions could substantially improve both morbidity and survival. The incidence of PAD in the general population is high, and currently affects 8–10 million Americans. The risk of developing PAD is predicted by both age and common atherosclerosis risk factors (e.g., smoking and diabetes). Efficient office-based PAD detection depends on the application of objective techniques to establish this diagnosis. Objective noninvasive tests, such as measurement of the ankle–brachial index (ABI), are known to be more sensitive than traditional clinical assessments. Since the major threat to patients with PAD is from secondary cardiovascular ischemic events, a primary therapeutic goal is to modify atherosclerotic risk factors. While national recommendations mandate aggressive lowering of serum low-density lipoprotein cholesterol (LDL-C) levels as a primary treatment goal in all patients with overt atherosclerosis, as 'coronary heart disease risk equivalent' syndromes, individuals with PAD are less intensively treated than those with CAD. Statins are the most effective of current treatments in lowering LDL-C, and have proven efficacy in secondary prevention among patients with established CAD. The use of statin medications in high-risk groups such as PAD patients could prove particularly beneficial in reducing cardiovascular morbidity and mortality and therefore merits prospective clinical investigation. [ABSTRACT FROM AUTHOR]

Presents a study to assess the feasibility of detecting peripheral arterial disease (PAD) in primary care clinics, patient and physician awareness of PAD, and intensity of risk factor treatment and use of antiplatelet therapies in primary care clinics. Design and setting; Patients; Main outcome measures; Results; Conclusions.

We aimed to evaluate whether carotid intima-media thickness (CIMT) or the presence of plaque can confer additional predictive value of future cardiovascular (CV) ischemic events in patients with pre-existing atherosclerotic vascular disease. We identified 2317 patients enrolled in the REduction of Atherothrombosis for Continued Health (REACH) registry who had atherosclerotic vascular disease and baseline CIMT measurements. The entire range of CIMT was divided into quartiles and the fourth quartile (≥ 1.5 mm) was defined as carotid plaque. Mean ± standard deviation baseline CIMT was 1.31 ± 0.65 mm. Associated CV ischemic events and vascular-related hospitalizations were evaluated over a 2-year follow-up. There was a positive increase in adjusted hazard ratios (HRs) for all-cause mortality (p = 0.04 for trend) and the quadruple endpoint (CV death, myocardial infarction (MI), stroke, hospitalization for CV events) with increasing quartiles of CIMT (p = 0.0008 for trend), which was mainly driven by the fourth quartile (carotid plaque). HRs for all-cause mortality, CV death, CV death/MI/stroke and the quadruple endpoint comparing the highest (carotid plaque) with the lowest CIMT quartile were 2.09 (95% CI, 1.07–4.10; p = 0.03); 2.49 (1.10–5.67; p = 0.03); 1.71 (1.10–2.67; p = 0.02); and 1.73 (1.31–2.27; p = 0.0001). In conclusion, our analyses suggest that the presence of carotid plaque, rather than the thickness of intima-media, appears to be associated with increased risk of CV morbidity and mortality, but confirmation of these findings in other population and prospective studies is required. [ABSTRACT FROM AUTHOR]

Background and aims Traditional glycemic markers, fasting glucose and hemoglobin A1c (HbA1c), predict incident peripheral artery disease (PAD). However, it is unknown whether nontraditional glycemic markers, fructosamine, glycated albumin, and 1,5-anhydroglucitol, are associated with PAD and whether these glycemic markers demonstrate particularly strong associations with severe PAD, critical limb ischemia (CLI). Methods We quantified the associations of these five glycemic markers with incident PAD (hospitalizations with PAD diagnosis or leg revascularization) in 11,634 ARIC participants using Cox regression models. Participants were categorized according to diabetes diagnosis and clinical cut-points of glycemic markers (nontraditional glycemic markers were categorized according to percentiles corresponding to the HbA1c cut-points). Results Over a median follow-up of 20.7 years, there were 392 cases of PAD (133 were CLI with tissue loss). HbA1c was more strongly associated with incident PAD than fasting glucose, with adjusted hazard ratios (HR) 6.00 (95% CI, 3.73–9.66) for diagnosed diabetes with HbA1c ≥ 7% and 3.53 (2.39–5.22) for no diagnosed diabetes with HbA1c ≥ 6.5% compared to no diagnosed diabetes with HbA1c <5.7%. Three nontraditional glycemic markers demonstrated risk gradients intermediate between HbA1c and fasting glucose and their risk gradients were substantially attenuated after adjusting for HbA1c. All glycemic markers consistently demonstrated stronger associations with CLI than PAD without CLI ( p for difference <0.02 for all glycemic markers). Conclusions Nontraditional glycemic markers were associated with incident PAD independent of fasting glucose but not necessarily HbA1c. Our results also support the importance of glucose metabolism in the progression to CLI. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate systemic and limb ischemic event rates of PAD patients with prior leg amputation and determine predictors of adverse outcomes. Methods: The REduction of Atherothrombosis for Continued Health (REACH) Registry provided a prospective multinational cohort of 7996 outpatients with PAD enrolled from primary medical clinics in 44 countries in 2003–2004. 1160 patients (14.5%) had a prior leg amputation at any level. Systemic (myocardial infarction [MI], stroke, cardiovascular death) and limb (angioplasty, surgery, amputation) ischemic event rates were determined in a 3-year follow-up. Results: PAD patients with leg amputations on entry had a 5-fold higher rate of a subsequent amputation (12.4% vs. 2.4%, P <.001), lower rate of peripheral angioplasty (8.3% vs. 10.7%, P =.005), and similar rates of surgical revascularization procedures compared with PAD patients without amputation. A nearly 2-fold increase in rates of cardiovascular death (14.5% vs. 7.7%, P <.001) and all-cause mortality (21.8% vs. 12.6%, P <.001) and an increase in the composite outcome of MI, stroke, cardiovascular death, or hospitalization (48.7% vs. 40.0%, P <.001) were noted. Recent (≤1 year) amputation was associated with higher rates of worsening PAD, subsequent lower extremity surgical revascularization procedures, re-amputation, non-fatal MI, and the composite outcome, including hospitalization. Adverse systemic and limb ischemic outcomes were similar regardless of amputation level. Conclusions: Individuals with a history of leg amputations have markedly elevated rates of systemic and limb-related outcomes. PAD patients with recent ischemic amputation have the highest risk of adverse events. A history of “minor” ischemic amputation may confer an identical systemic risk as “major” leg amputation. [Copyright &y& Elsevier]

To determine whether elevated levels of hemostatic and inflammatory markers [von Willebrand factor (vWF), fibrinogen, D-dimer, factor VII, factor VIII, PAI-1, tPA, beta-thromboglobulin ( β-TG), CRP, and WBC count] are associated with increased peripheral arterial disease (PAD) prevalence, measured by low ABI, we studied 13,778 participants from the ARIC study in a cross-sectional analysis after adjustment for major cardiovascular risk factors. PAD was positively associated with fibrinogen, vWF, factor VIII, WBC count, D-dimer, β-TG, and CRP ( pfor trend <0.05) but not with the other markers. Adjusted odds ratios for the highest versus the lowest quartile of fibrinogen in men and women, respectively, were 3.49 (95% CI 1.68-7.26) and 2.44 (95% CI 1.58-3.77); for vWF 2.36 (95% CI 1.36-4.07) and 1.45 (95% CI 1.00-2.10); for factor VIII 2.31 (95% CI 1.36-3.94) and 1.68 (95% CI 1.14-2.48). In a smaller subset, the sex and risk factor adjusted odds ratio for the highest versus the lowest quartile of D-dimer was 2.70 (95% CI 1.56-4.65), for β-TG was 1.80 (95% CI 1.12-2.88), and for CRP was 1.57 (95% CI 0.84-2.95). Plasma levels of hemostatic and inflammatory markers are elevated in PAD, suggesting these processes are involved in the pathophysiology of PAD. [ABSTRACT FROM AUTHOR]

The article discusses a study documenting cardiovascular (CV) events over one year in outpatients diagnosed with atherothrombosis. The Reduction of Atherothrombosis for Continued Health (REACH) Registry was established with almost 70,000 patients with atherosclerotic arterial disease (AAD) or at least three risk factors for atherothrombosis in 2003-2004. The study found that outpatients with or at risk for AAD had relatively high annual CV event rates. The author believes that continued efforts are needed to improve secondary prevention and clinical outcomes.

Abstract: Background: The clinical significance of a high ankle-brachial index (ABI), defined by the associated risk factor burden and ischemic risk, is largely unknown. Methods: Using data from the Atherosclerosis Risk in Communities Study, we categorized 14,777 participants into normal (ABI between 0.9 and 1.3) and high ABI groups (ABI>1.3, >1.4, and >1.5) and compared the risk factor profile and CVD event rates of the normal ABI group to each high ABI group. Results: The prevalence of high ABI was 5.5% for ABI>1.3, 1.2% for ABI>1.4, and 0.37% for ABI>1.5. Compared with participants with a normal ABI, those with ABI>1.3 had a lower prevalence of hypertension and current smoking. The ABI>1.3 group had a greater mean body mass index, but was characterized by fewer pack years of smoking and lower systolic and diastolic blood pressures than the normal ABI group. The prevalence of diabetes, left ventricular hypertrophy, claudication, and coronary heart disease and mean values of fibrinogen, factor VIII activity, von Willebrand factor, lipoprotein (a), and carotid and popliteal intimal-medial thickness were similar between the two ABI groups. The risk factor profiles of the ABI>1.4 and >1.5 groups were also not statistically significantly different from that of the normal ABI group. Over a mean follow-up time of 12.2 years, the age, sex, and race-adjusted CVD event rates per 1000 person years were 8.1 in the normal ABI group, 7.6 in the ABI>1.3 group, 7.6 in the ABI>1.4 group, and 7.4 in the ABI>1.5 group. The CVD event rates of the high ABI groups were similar to that of the normal ABI group. Conclusion: Individuals with a high ABI are not characterized by a more adverse atherosclerosis risk factor profile and do not suffer greater CVD event rates than those with a normal ABI. [Copyright &y& Elsevier]

There is mounting evidence to suggest that psychosocial factors, including anger proneness, depression and social isolation, are risk factors for cardiovascular disease. Nevertheless, evidence relating these factors to peripheral arterial disease (PAD) and intermittent claudication remains sparse. Using data from the Atherosclerosis Risk in Communities Study, we analyzed the relationship of psychosocial variables (Spielberger anger score, depression score from the Maastricht questionnaire, and a perceived social support scale) at study visit 2 with incident PAD (ankle-brachial index ≤0.9; a hospital discharge diagnosis of PAD, leg amputation, or leg revascularization procedures; or intermittent claudication). In 12 965 middle-aged adults with no prior history of PAD, 854 developed PAD over a mean follow-up time of 9.7 years, yielding an incidence rate of 6.8 per 1000 person years. A modest, monotonic dose–response, positive association between anger proneness and incident PAD was observed in a multivariable model: relative risk (RR) = 1.15 (95% confidence interval (CI) 0.99–1.38) in the moderate anger group and RR = 1.38 (95% CI 1.08–1.76) in the high anger group, compared with the low anger group. When compared with a low level of depressive symptoms, moderate and high levels of depressive symptoms were also associated with greater incident PAD, with multivariable RRs of 1.20 (95% CI 0.99–1.45) and 1.44 (95% CI 1.19–1.74) respectively. There was no association of perceived level of social support with the occurrence of PAD. Anger proneness and depressive symptoms may be associated with the occurrence of PAD, as for other atherosclerotic syndromes. These findings may warrant confirmation in further studies and, if causal, could serve as a unique target for a PAD prevention trial. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Individuals with peripheral arterial disease (PAD) have a 3- to 6-fold increased risk of coronary heart disease and stroke compared to those without PAD. We documented physician-reported practice behavior, knowledge, and attitudes regarding atherosclerotic risk factor reduction in patients with PAD. DESIGN: National physician survey. PATIENTS/PARTICIPANTS: General internists (N = 406), family practitioners (N = 435), cardiologists (N = 473), and vascular surgeons (N = 264) randomly identified using the American Medical Association's physician database. MEASUREMENTS AND MAIN RESULTS: Physicians were randomized to 1 of 3 questionnaires describing a) a 55- to 65-year-old patient with PAD; b) a 55- to 65-year-old patient with coronary artery disease (CAD), or c) a 55- to 65-year-old patient without clinically evident atherosclerosis (no disease). A mailed questionnaire was used to compare physician behavior, knowledge, and attitude regarding risk factor reduction for each patient. Rates of prescribed antiplatelet therapy were significantly lower for the patient with PAD than for the patient with CAD. Average low-density lipoprotein levels at which physicians “almost always” initiated lipid-lowering drugs were 121.6 ± 23.5 mg/dL, 136.3 ± 28.9 mg/dL, and 149.7 ± 24.4 mg/dL for the CAD, PAD, and no-disease patients, respectively (P < .001). Physicians stated that antiplatelet therapy (P < .001) and cholesterol-lowering therapy (P < .001) were extremely important significantly more often for the CAD than for the PAD patient. Perceived importance of risk factor interventions was highly correlated with practice behavior. Compared to other specialties, cardiologists had lowest thresholds, whereas vascular surgeons had the highest thresholds for initiating cholesterol-lowering interventions for the patient with PAD. Cardiologists were significantly more likely to report “almost always” prescribing antiplatelet therapy... [ABSTRACT FROM AUTHOR]