Association between secondhand smoke and peripheral arterial disease: a meta-analysis of cross-sectional studies.

PURPOSE: The association between secondhand smoke (SHS) and peripheral arterial disease (PAD) was inconsistent and the studies were relatively scarce, hence, we conducted a meta-analysis of the association between SHS and PAD. MATERIALS AND METHODS: We systematically searched three electronic databases (PubMed, EMBASE, and Web of Science), and calculated the pooled prevalence risk ratio (RR) and estimated standard error by random effect model from the meta-analysis. Furthermore, we performed a subgroup meta-analysis according to the location of SHS exposure. RESULTS: We initially identified 502 articles from the electronic database, and 6 articles, cross-sectional data from 4 cross-sectional studies and 2 prospective cohort studies, were included in the meta-analysis. Among these six articles, two studies showed a significant correlation between SHS exposure and PAD, whereas no study showed a negative correlation between SHS exposure and PAD. In the meta-analysis, pooled prevalence showed a significant association between SHS exposure and PAD (RR = 1.23; 95% confidence interval [CI] 1.08-1.41; z = 3.02, p = 0.003). In the subgroup analysis based on location of SHS exposure, the prevalence RR of PAD at home was 1.30 (95% CI 1.14-1.49, Z-3.99, p < 0.0001). The prevalence RR in the subgroup of SHS exposure at work was not significant (RR = 0.89; 95% CI 0.55-1.44; z = 0.48, p = 0.63). CONCLUSION: Exposure to SHS was significantly and positively associated with PAD. Moreover, we found a significant association between exposure to SHS and PAD at home, but the association was not significant at work.

Intake of marine n-3 polyunsaturated fatty acids and the risk of incident peripheral artery disease.

BACKGROUND: A high intake of marine n-3 polyunsaturated fatty acids (PUFAs) may lower the risk of coronary heart disease and ischemic stroke. The association between intake of marine n-3 PUFAs and development of peripheral artery disease (PAD), however, remains unexplored. We hypothesised that intake of marine n-3 PUFAs, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and the sum of EPA + DHA was associated with a lower risk of incident PAD. METHODS: We used data from the Danish Diet, Cancer and Health cohort and investigated the associations between intake of EPA, DHA and EPA + DHA and development of PAD. Information on intake of n-3 PUFAs was obtained through a validated food frequency questionnaire. Potential PAD cases were identified through linkage to the Danish National Patient Register and subsequently, all cases were validated. RESULTS: Data were available from 55,248 participants and during a median of 13.6 years of follow-up, 950 cases of PAD were identified. Multivariate Cox regression analyses with adjustments for established risk factors showed no statistically significant associations between intake of EPA (p = 0.255), DHA (p = 0.071) or EPA + DHA (p = 0.168) and the rate of incident PAD. CONCLUSIONS: We did not confirm our hypothesis that intake of EPA, DHA or EPA + DHA was associated with a lower risk of incident PAD.

Effect of Creatine Supplementation on Functional Capacity and Muscle Oxygen Saturation in Patients with Symptomatic Peripheral Arterial Disease: A Pilot Study of a Randomized, Double-Blind Placebo-Controlled Clinical Trial.

The aim of the study was to verify the effects of creatine (Cr) supplementation on functional capacity (walking capacity; primary outcome) and calf muscle oxygen saturation (StO2) (secondary outcome) in symptomatic peripheral arterial disease (PAD) patients. Twenty-nine patients, of both sexes, were randomized (1:1) in a double-blind manner for administration of placebo (PLA, n = 15) or creatine monohydrate (Cr, n = 14). The supplementation protocol consisted of 20 g/day for 1 week divided into four equal doses (loading phase), followed by single daily doses of 5 g in the subsequent 7 weeks (maintenance phase). Functional capacity (total walking distance) was assessed by the 6 min walk test, and calf muscle StO2 was assessed through near infrared spectroscopy. The measurements were collected before and after loading and after the maintenance phase. The level of significance was p < 0.05. No significant differences were found for function capacity (total walking distance (PLA: pre 389 ± 123 m vs. post loading 413 ± 131 m vs. post maintenance 382 ± 99 m; Cr: pre 373 ± 149 m vs. post loading 390 ± 115 m vs. post maintenance 369 ± 115 m, p = 0.170) and the calf muscle StO2 parameters (p > 0.05). Short- and long-term Cr supplementation does not influence functional capacity and calf muscle StO2 parameters in patients with symptomatic PAD.

Pre-Clinical Investigation of Keratose as an Excipient of Drug Coated Balloons.

BACKGROUND: Drug-coated balloons (DCBs), which deliver anti-proliferative drugs with the aid of excipients, have emerged as a new endovascular therapy for the treatment of peripheral arterial disease. In this study, we evaluated the use of keratose (KOS) as a novel DCB-coating excipient to deliver and retain paclitaxel. METHODS: A custom coating method was developed to deposit KOS and paclitaxel on uncoated angioplasty balloons. The retention of the KOS-paclitaxel coating, in comparison to a commercially available DCB, was evaluated using a novel vascular-motion simulating ex vivo flow model at 1 h and 3 days. Additionally, the locoregional biological response of the KOS-paclitaxel coating was evaluated in a rabbit ilio-femoral injury model at 14 days. RESULTS: The KOS coating exhibited greater retention of the paclitaxel at 3 days under pulsatile conditions with vascular motion as compared to the commercially available DCB (14.89 ± 4.12 ng/mg vs. 0.60 ± 0.26 ng/mg, p = 0.018). Histological analysis of the KOS-paclitaxel-treated arteries demonstrated a significant reduction in neointimal thickness as compared to the uncoated balloons, KOS-only balloon and paclitaxel-only balloon. CONCLUSIONS: The ability to enhance drug delivery and retention in targeted arterial segments can ultimately improve clinical peripheral endovascular outcomes.

Xarelto plus Acetylsalicylic acid: Treatment patterns and Outcomes in patients with Atherosclerosis (XATOA): Rationale and design of a prospective registry study to assess rivaroxaban 2.5 mg twice daily plus aspirin for prevention of atherothrombotic events in coronary artery disease, peripheral artery disease, or both.

Patients with coronary artery disease (CAD), peripheral artery disease (PAD), or both remain at risk of cardiovascular events (including peripheral ischemic events), even when they receive the current guideline-recommended treatment. The phase III COMPASS trial demonstrated that treatment with rivaroxaban vascular dose 2.5 mg twice daily plus aspirin (dual pathway inhibition [DPI] regimen) significantly reduced the risk of major adverse cardiovascular events (including peripheral ischemic events) and increased the risk of major bleeding, but not fatal bleeding or intracranial hemorrhage, versus aspirin alone in patients with CAD, PAD, or both. The results of the COMPASS trial supported the regulatory approval of the DPI regimen in several geographic regions. However, it is unclear whether the patients selected for treatment with the DPI regimen in clinical practice will have a similar risk profile and event rates compared with the COMPASS trial population. The prospective post-approval XATOA registry study aims to assess treatment patterns, as well as ischemic and bleeding outcomes in patients with CAD, PAD, or both, who receive DPI therapy in routine clinical practice. Up to 10,000 patients from at least 400 centers in 22 countries will be enrolled and followed up for a minimum of 12 months, and all treatment will be at the discretion of the prescribing physician. The primary objective of the XATOA study will be to describe early treatment patterns, while ischemic and bleeding outcomes will be described as a secondary objective. TRIAL REGISTRATION NUMBER: NCT03746275.

Vitamin D as A Protector of Arterial Health: Potential Role in Peripheral Arterial Disease Formation.

Atherosclerotic occlusive diseases and aneurysms that affect large and medium-sized arteries outside the cardiac and cerebral circulation are collectively known as peripheral arterial disease (PAD). With a rise in the rate of aging population worldwide, the number of people diagnosed with PAD is rapidly increasing. The micronutrient vitamin D is an important steroid hormone that acts on many crucial cellular mechanisms. Experimental studies suggest that optimal levels of vitamin D have beneficial effects on the heart and blood vessels; however, high vitamin D concentrations have been implicated in promoting vascular calcification and arterial stiffness. Observations from various clinical studies shows that deficiency of vitamin D has been associated with a greater risk of PAD. Epidemiological studies have often reported an inverse relation between circulating vitamin D status measured in terms of 25-hydroxivitamin D [25(OH)D] levels and increased cardiovascular disease risk; however, randomized controlled trials did not show a consistent positive effect of vitamin D supplementation on cardiovascular disease risk or events. Even though PAD shares all the major risk factors with cardiovascular diseases, the effect of vitamin D deficiency in PAD is not clear. Current evidence suggests a strong role of vitamin D in promoting genomic and epigenomic changes. This review summarises the current literature that supports the notion that vitamin D deficiency may promote PAD formation. A better understanding of underlying pathological mechanisms will open up new therapeutic possibilities which is the main unmet need in PAD management. Furthermore, epigenetic evidence shows that a more holistic approach towards PAD prevention that incorporates a healthy lifestyle, adequate exercise and optimal nutrition may be more effective in protecting the genome and maintaining a healthy vasculature.

Sodium Tanshinone IIA sulfonate improves post-ischemic angiogenesis in hyperglycemia.

BACKGROUND: Diabetes is a strong risk factor of peripheral arterial disease (PAD), and also leads to impaired perfusion recovery in the ischemic limb, which eventually results in poor outcomes in PAD patients. Sodium Tanshinone IIA Sulfonate (STS), a monomer from herbs, has been shown to improve the outcomes in a variety of ischemic disease including myocardial infarction. However, the effects of STS treatment in PAD is not known. METHODS AND RESULTS: Unilateral femoral artery was ligated in mice as experimental PAD models, STS treatment improved perfusion recovery, increased capillary densities, decreased reactive oxygen species (ROS) level and microRNA-133a (miR-133a) expression in the ischemic hindlimb in diabetic mice; however, STS did not change perfusion recovery in non-diabetic C57BL/6 mice. Ischemic muscle tissue from diabetic mice was harvested 7 days after femoral ligation for biochemical test, STS resulted in reduced malondialdehyde (MDA), and increased GTP cyclohydrolase 1 (GCH1) and cyclic guanine monophosphate (cGMP) levels. In addition, STS treatment increased miR-133a expression in endothelial cells isolated from ischemic muscle tissue of diabetic mice. In endothelial cells cultured in high glucose medium, STS increased tube formation and nitric oxide (NO) production, and reduced cellular ROS level and miR-133a expression under simulated ischemic condition. In addition, GCH1 inhibitor or miR-133a overexpression using exogenous microRNA mimic blunted STS-induced angiogenic effects and ROS neutralization in cultured endothelial cells under hyperglycemic and hypoxic conditions. CONCLUSION: These findings demonstrate STS improves angiogenesis via inhibiting miR-133a expression and increasing GCH-1 protein levels in experimental PAD with diabetes.

Global, regional, and national prevalence and risk factors for peripheral artery disease in 2015: an updated systematic review and analysis.

BACKGROUND: Peripheral artery disease is a major cardiovascular disease that affected 202 million people worldwide in 2010. In the past decade, new epidemiological data on peripheral artery disease have emerged, enabling us to provide updated estimates of the prevalence and risk factors for peripheral artery disease globally and regionally and, for the first time, nationally. METHODS: For this systematic review and analysis, we did a comprehensive literature search for studies reporting on the prevalence of peripheral artery disease in the general population that were published between Jan 1, 2011, and April 30, 2019, in PubMed, MEDLINE, Embase, the Global Health database, CINAHL, the Global Health Library, the Allied and Complementary Medicine Database, and ProQuest Dissertations and Theses Global. We also included the Global Peripheral Artery Disease Study of 2013 and the China Peripheral Artery Disease Study as sources. Peripheral artery disease had to be defined as an ankle-brachial index lower than or equal to 0·90. With a purpose-built data collection form, data on study characteristics, sample characteristics, prevalence, and risk factors were abstracted from all the included studies identified from the sources. Age-specific and sex-specific prevalence of peripheral artery disease was estimated in both high-income countries (HICs) and low-income and middle-income countries (LMICs). We also did random-effects meta-analyses to pool the odds ratios of 30 risk factors for peripheral artery disease in HICs and LMICs. UN population data were used to generate the number of people affected by the disease in 2015. Finally, we derived the regional and national numbers of people with peripheral artery disease on the basis of a risk factor-based model. FINDINGS: We included 118 articles for systematic review and analysis. The prevalence of peripheral artery disease increased consistently with age. At younger ages, prevalence was slightly higher in LMICs than HICs (4·32%, 95% CI 3·01-6·29, vs 3·54%, 1·17-10·24, at 40-44 years), but the increase with age was greater in HICs than LMICs, leading to a higher prevalence in HICs than LMICs at older ages (21·24%, 15·22-28·90, vs 12·04%, 8·67-16·60, at 80-84 years). In HICs, prevalence was slightly higher in women than in men up to age 75 years (eg, 7·81%, 3·97-14·77, vs 6·60%, 3·74-11·38, at 55-59 years), whereas in LMICs little difference was found between women and men (eg, 6·40%, 5·06-8·05, vs 6·37%, 4·74-8·49, at 55-59 years). Overall, the global prevalence of peripheral artery disease in people aged 25 years and older was 5·56%, 3·79-8·55, and the prevalence estimate was higher in HICs than that in LMICs (7·37%, 4·35-13·66, vs 5·09%, 3·64-7·24). Smoking, diabetes, hypertension, and hypercholesterolaemia were major risk factors for peripheral artery disease. Globally, a total of 236·62 million people aged 25 years and older were living with peripheral artery disease in 2015, among whom 72·91% were in LMICs. The Western Pacific Region had the most peripheral artery disease cases (74·08 million), whereas the Eastern Mediterranean Region had the least (14·67 million). More than two thirds of the global peripheral artery disease cases were concentrated in 15 individual countries in 2015. INTERPRETATION: Peripheral artery disease continues to become an increasingly serious public health problem, especially in LMICs. With the demographic trend towards ageing and projected rise in important risk factors, a larger burden of peripheral artery disease is to be expected in the foreseeable future. FUNDING: None.

Long-Term Clinical and Angiographic Outcomes After Implantation of New-Generation Drug-Eluting Stents for Patients on Maintenance Hemodialysis.

Prior research has revealed poorer clinical outcomes after drug-eluting stent (DES) implantation for hemodialysis patients. This study aims to investigate the long-term clinical and angiographic outcomes after new-generation DES implantation for hemodialysis patients.We retrospectively enrolled 91 consecutive patients (118 lesions) who underwent successful new-generation DES (everolimus-, zotarolimus-, and biolimus-eluting stents) implantation for the first time. We measured the serum calcium and phosphorus levels in the blood samples obtained just before hemodialysis. The follow-up period of clinical events was, at least, 1.5 years. In this study, major adverse cardiac and cerebrovascular events (MACCE) and clinically driven target lesion revascularization were reported in 36 (39.6%) and 11 (12.1%) patients, respectively. The prevalence of peripheral artery disease was significantly higher in the MACCE group (41.7% versus 14.5%, P = 0.006). The serum calcium level was significantly higher in the MACCE group (9.34 ± 0.92 mg/dL versus 8.77 ± 0.88 mg/dL; P = 0.004). The multivariate Cox proportional hazards model revealed that the serum calcium level (hazard ratio, 1.86; 95% confidence interval [CI]: 1.26-2.77; P = 0.002), suboptimal (over 55 mg2/dL2) calcium-phosphorus product (hazard ratio, 3.27; 95% CI: 1.41-7.61; P = 0.006) and the coexistence of peripheral artery disease (hazard ratio, 3.15; 95% CI: 1.49-6.65; P = 0.003) were independent predictors of MACCE.For hemodialysis patients, MACCE remains a frequent occurrence after new-generation DES implantation and is associated with calcium-phosphate metabolism and peripheral artery disease.

Effectiveness and safety of rivaroxaban and warfarin for prevention of major adverse cardiovascular or limb events in patients with non-valvular atrial fibrillation and type 2 diabetes.

AIMS: To assess the effectiveness and safety of rivaroxaban versus warfarin for the prevention of major adverse cardiovascular events (MACE) and major adverse limb events (MALE) in patients with type 2 diabetes (T2D) and non-valvular atrial fibrillation (NVAF). MATERIALS AND METHODS: Using MarketScan data from January 2012 to December 2017, we identified oral anticoagulant-naïve patients with NVAF and comorbid T2D and ≥12 months of insurance coverage prior to rivaroxaban or warfarin initiation. Differences in baseline covariates between cohorts were adjusted for using inverse probability of treatment weights based on propensity scores (absolute standardized differences <0.1 achieved for all covariates after adjustment). Patients were followed until a MACE, MALE or major bleeding event, oral anticoagulant discontinuation/switch, insurance disenrolment or end of data availability. Hazard ratios (HRs) and 95% confidence intervals (CIs) comparing the cohorts were calculated using Cox regression. RESULTS: We identified 10 700 rivaroxaban users (24.1% received a reduced dose) and 13 946 warfarin users. The median (25%, 75% range) age was 70 (62, 79) years, CHA2DS2-VASc score was 4 (3, 5) and duration of available follow-up was 1.4 (0.6, 2.7) years. Eleven percent of patients had peripheral artery disease, 5.1% had coronary artery disease, and 5.1% had a prior MALE, at baseline. Rivaroxaban was associated with a 25% (95% CI 4-41) reduced risk of MACE and a 63% (95% CI 35-79) reduced risk of MALE compared to warfarin. Major bleeding risk did not significantly differ between cohorts (HR 0.95). CONCLUSIONS: Among patients with NVAF and T2D treated in routine practice, rivaroxaban was associated with lower risks of both MACE and MALE versus warfarin, with no significant difference in major bleeding.

Anticoagulation in Atherosclerotic Disease.

The prevention of atherothrombotic events is an essential therapeutic goal in the treatment of patients with arteriosclerotic diseases. After plaque rupture, a rapidly growing thrombus can lead to acute vascular occlusion and thus heart attack, stroke or limb ischaemia. The acute therapy combines anticoagulation and platelet inhibition. However, the only available therapy so far in the primary and secondary prevention of stable patients is the platelet inhibitors aspirin and clopidogrel. Despite the use of antiplatelet therapies, including aspirin and P2Y12-receptor antagonists, some patients with artery disease continue to experience recurrent cardiovascular ischaemic events due to excessive thrombin generation beyond the acute period. As a result, studies have tested non-vitamin K antagonist oral anticoagulants (NOACs), specifically the factor Xa inhibitors, either alone or in combination with antiplatelet therapy, in the management of arterial disease. For the first time, the COMPASS study investigated low-dose anticoagulation in stable coronary heart disease or peripheral arterial disease. The addition of 2 × 2.5 mg rivaroxaban to long-term aspirin therapy not only prevented cardiovascular death, myocardial infarction and stroke, but even reduced all-cause mortality by a relative 18% after a mean follow-up of 23 months. This benefit came at the expense of more gastrointestinal bleeding, which might be reduced by the addition of a proton pump inhibitor (investigations are ongoing). Interestingly, however, there was no increase in fatal or intracranial haemorrhages. Therefore, a new standard therapy for high-risk patients with atherosclerotic disease may become available in the near future.

Low molecular weight fucoidan ameliorates hindlimb ischemic injury in type 2 diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Low molecular weight fucoidan (LMWF), extracted from Laminaria japonica Areschoug, is a traditional Chinese medicine, commonly used to alleviate edema, particularly for feet with numbness and pain. AIM OF THE STUDY: Diabetic mellitus (DM) patients are at high risk of developing peripheral arterial disease (PAD). Individuals with DM and PAD co-morbidity have a much higher risk of critical limb ischemia. LMWF showed several beneficial effects, such as anti-inflammation, anti-thrombosis, and enhancing revascularization. Therefore, we hypothesized that LMWF might be beneficial to diabetes-induced PAD, and investigated the therapeutic potential of LMWF on diabetic PAD rats. MATERIALS AND METHODS: Type 2 diabetic Goto-Kakizaki (GK) rats were made PAD by injection of sodium laurate into femoral artery. LMWF (20, 40 or 80mg/kg/day) or cilostazol (100mg/kg/day) were given to diabetic PAD rats for 4 weeks, respectively. The effects of LMWF on foot ulceration and claudication, plantar blood flow, collateral vessel formation, endothelium morphology, gastrocnemius injury, platelet aggregation, vessel vasodilation, and the expressions of inflammation factors, VEGF, eNOS, and nitric oxide were measured. RESULTS: We found that LMWF markedly ameliorated foot ulceration and claudication, and improved the plantar perfusion by reversing hyperreactive platelet aggregation, ameliorating endothelium-dependent vasodilation and revascularization on diabetic PAD rats. In addition, upregulation of several inflammatory factors, such as ICAM-1 and IL-1ß in the gastrocnemius muscles of ischemic hindlimb were suppressed by LMWF administration. And eNOS phosphorylation at Ser1177 and NO production were significantly enhanced in LMWF-treated diabetic PAD rats. CONCLUSIONS: Taken together, our findings demonstrated that LMWF exhibits therapeutic effect on hindlimb ischemia in type 2 diabetic rats likely through ameliorating endothelium eNOS dysfunction and enhancing revascularization, thus, providing a potential supplementary non-invasive treatment for diabetes-induced PAD.

Dietary patterns, plasma vitamins and Trans fatty acids are associated with peripheral artery disease.

BACKGROUND: To investigate the association between dietary patterns (DP), plasma vitamins and trans fatty acids (TFAs) with the likelihood of peripheral artery disease (PAD). METHODS: National Health and Nutrition Examination Survey (NHANES) data for the years 1999-2002 were used. PAD was diagnosed by ankle brachial index assessment. Plasma concentrations of vitamins were measured using high performance liquid chromatography. Vitamin D levels were measured by radioimmunoassay. Analysis of covariance, principal components analysis (PCA) and adjusted logistic regression were applied, accounting for the survey design and sample weights. RESULTS: Of the 4864 eligible participants, 2482 (51.0%) were men and 269 (5.5%) had prevalent PAD. PCA uncovered three DPs which accounted for 56.8% of the variance in dietary nutrients consumption including DP1 (fatty acids and cholesterol), DP2 (minerals, vitamins and fiber), and DP3 (polyunsaturated fatty acids [PUFA]). PAD patients had a significantly higher serum concentrations of trans 9-octadecenoic acid and trans 9, trans 12-octadienoic acid as well as lower plasma levels of vitamin D, retinol, retinyl stearate and retinyl palmitate (p < 0.001 for all comparisons). In models adjusted for age, race, diabetes, cholesterol, hypertension, smoking and energy intake, individuals in the highest quartile of the DP1 had higher odds for PAD compared with those in the lowest quartile [(odds ratio (OR): 6.43, 95% confidence interval (CI): 2.00-20.63 p < 0.001], while those in the highest quartile of DP2 and DP3 had lower odds of PAD relative to those in the lowest quartile (OR:0.28, OR:0.44, respectively; p < 0.001 for both comparisons). CONCLUSION: We found that quality of diet, plasma vitamins and TFAs are associated with the likelihood of PAD. If confirmed in prospective studies, the possibility that dietary factors, plasma vitamins and TFAs might be valuable for preventing or delaying the clinical progression of PAD, should be investigated in intervention trials.

Dietary intake and peripheral arterial disease incidence in middle-aged adults: the Atherosclerosis Risk in Communities (ARIC) Study.

Background: Peripheral arterial disease (PAD) is a costly source of morbidity and mortality among older persons in the United States. Dietary intake plays a role in the development of atherosclerotic cardiovascular disease; however, few studies have examined the relation of food intake or dietary patterns with PAD.Objective: We examined the relation between habitual dietary intake at midlife and incident PAD over ∼20 y of follow-up.Design: Among 14,082 participants enrolled in the ARIC (Atherosclerosis Risk in Communities) Study initially free of PAD, dietary intake was assessed at baseline in 1987-1989 by using a modified Harvard food-frequency questionnaire. Food groups were created, and principal components analysis was used to develop "healthy" and "Western" dietary patterns; both were categorized into quintiles or quartiles. Incident PAD was determined by an ankle-brachial index <0.9 assessed at 2 subsequent examinations and hospital discharge codes through 2012. Multivariate-adjusted Cox proportional hazards regression was used.Results: During a mean follow-up of 19.9 y, 1569 participants developed incident PAD. In models adjusted for demographic characteristics, behaviors, and food groups, the HRs (95% CIs) for incident PAD increased across quintiles of meat consumption [quintile 1: reference, quintile 2: 1.38 (1.16, 1.65), quintile 3: 1.38 (1.16, 1.65), quintile 4: 1.45 (1.20, 1.74), quintile 5: 1.66 (1.36, 2.03); P-trend <0.001]. Compared with those who drank no alcohol, those who had 1-6 drinks/wk had a lower risk of incident PAD [0.78 (0.68, 0.89)]. For coffee, ≥4 cups/d compared with none was inversely associated with incident PAD [quintile 5 compared with quintile 1: 0.84 (0.75, 1.00); P-trend = 0.014]. There was no association between other food groups or patterns and incident PAD.Conclusions: In this prospective cohort study, greater meat consumption was associated with a higher risk, and moderate alcohol consumption was associated with a lower risk of incident PAD. Whether these associations are causal remains to be seen. This trial was registered at clinicaltrials.gov as NCT00005131.

The Use of Transcutaneous Electrical Stimulation of the Calf in Patients Undergoing Infrainguinal Bypass Surgery.

BACKGROUND: Infrainguinal bypass surgery is frequently associated with postoperative reperfusion edema of the limb. The etiology is thought to be multifactorial, and there is as yet no standardized treatment protocol for this problem. The primary aim of this study was to assess whether the use of intermittent electrical stimulation of the calf muscles after infrainguinal bypass surgery was effective in reducing the incidence of edema, and the secondary aims to determine the effect of calf muscle stimulation on arterial and venous flow in the operated leg. METHODS: Forty patients due to undergo infrainguinal bypass surgery for critical lower-limb ischemia (Fontaine grading III-IV or Rutherford grading II-III) were recruited prospectively and randomly divided into the control group, who received the current standard of care, and study group, who received electrical calf muscle stimulation for a 1 hour session twice daily for the first postoperative week. Preoperatively and postoperatively, the leg was measured at 3 predetermined points and a duplex ultrasound scan performed. RESULTS: The groups were well matched for all parameters. At 1 week, the below knee and calf girth were less in the study group (P = 0.025 and P = 0.043, respectively). Venous flow volumes at rest and on stimulation were higher in the study group (P = 0.010 and P = 0.029, respectively). At 6 weeks, the below knee girth and amount of pitting edema were less in the study group (P = 0.011 and P = 0.014, respectively). CONCLUSIONS: We conclude that transcutaneous electrical stimulation of the calf decreased lower-limb swelling at 1 and 6 weeks, and increased the venous flow volume at rest and on stimulation at 1 week in patients undergoing infrainguinal bypass surgery for critical ischemia regardless of patient factors or the type of bypass surgery performed or graft used.

Clinical correlates of red blood cell omega-3 fatty acid content in male veterans with peripheral arterial disease.

OBJECTIVE: Despite available medical therapies, patients with peripheral arterial disease (PAD) remain at high risk for cardiovascular events. The n-3 polyunsaturated fatty acids (PUFA), derived from marine sources, have been shown to improve cardiovascular mortality. The Omega-3 Index (O3I), a proportion of the n-3 PUFA eicosapentaenoic acid and docosahexaenoic acid in the red blood cell membrane, correlates with cardiovascular risk. Previous investigations have found that n-3 PUFA supplementation, fish consumption, older age, and smoking history affect the O3I in different patient populations, although similar correlations have never been explored in PAD. We hypothesized that in our PAD cohort, blood content of omega-3 fatty acids would directly and positively correlate with a history of fish oil supplementation and older age and inversely correlate with a smoking history and obesity. METHODS: This cross-sectional study included 111 patients who had an ankle-brachial index of <0.9 associated with claudication symptoms. We used linear regression to determine the association between clinical factors and the O3I. RESULTS: The mean age of the cohort was 69 ± 8 years; 37% had diabetes mellitus (hemoglobin A1c, 7% ± 1%), and 94% reported current smoking or a history of smoking. The mean O3I was 5% ± 2%. In multivariate linear regression analysis, the O3I was associated with older age, increasing body mass index, and a history of smoking and fish oil intake. CONCLUSIONS: This is the first report of the relation between blood content of omega-3 fatty acids and clinical factors in a PAD population. In patients with PAD, older age, elevated body mass index, and prior fish oil supplementation predicted a higher O3I. A history of smoking correlated with a lower O3I. These results demonstrate that the O3I is a reliable measure of dietary n-3 PUFA intake and that clinical factors related to the O3I in PAD are similar to those observed in other populations.

Vitamin D status and peripheral arterial disease: evidence so far.

BACKGROUND: Vitamin D deficiency has recently been implicated as a contributory factor in the development of peripheral arterial disease (PAD). METHODS: A review of the published literature on PAD and vitamin D was undertaken using Medline, PubMed, and Embase, and cross-referenced. All relevant published papers on the subject were reviewed. RESULTS: Published studies have shown that there is a significant association between vitamin D and PAD. Populations with lower vitamin D levels are more likely to develop PAD in a graded manner. Higher amputation rates are also observed among patients with PAD and lower vitamin D levels. In addition, vitamin D deficiency is significantly associated with increased risk of cardiovascular adverse events. This was also observed in the mouse model where low vitamin D led to the development of atherosclerosis. CONCLUSION: This study shows that vitamin D deficiency could be an independent risk factor for the development of PAD and that this risk factor is easily correctable. Further studies should look into the effects of vitamin D supplementation in patients with PAD.

The prevalence of asymptomatic and symptomatic peripheral arterial disease and peripheral arterial disease risk factors in the U.S. population.

The National Health and Nutrition Examination Survey 2003 to 2004 data set was utilized to examine trends and differences of individuals with asymptomatic and symptomatic peripheral arterial disease (PAD) and PAD risk factor variables, determined by Ankle-Brachial Index measurement. A descriptive secondary data analysis was conducted by using the variables age, gender, hypertension (ie, systolic blood pressure and diastolic blood pressure), dyslipidemia (ie, high-density lipoprotein and low-density lipoprotein), diabetes, and cigarette smoking.

Trace elements and toxic heavy metals play a role in Buerger disease and atherosclerotic peripheral arterial occlusive disease.

AIM: The aim of the present study was to define the roles of trace elements and toxic heavy metals in Buerger disease and atherosclerotic peripheral arterial occlusive disease (PAOD). METHODS: Seventy-five subjects who were identical in demographic charecteristics were selected for the study; 25 with Buerger disease, 25 with PAOD, 25 healthy volunteers. Serum selenium (Se), zinc (Zn), copper (Cu), iron (Fe),whole blood cadmium (Cd) and lead (Pb), erythrocyte glutathione (GSH), erythrocyte glutathione peroxidase (GSH-Px), erythrocyte and plasma malondialdehyde (MDA) levels were measured. RESULTS: Serum Se and Zn levels were significantly low in patients with Buerger disease compared to patients with PAOD and controls (P<0.001 and P<0.001 respectively). Serum levels of Fe and Zn were also significantly low in patients with PAOD compared to controls (p<0.001 and p<0.05 respectively). In contrast, Cu and Pb levels in Buerger disease group were significantly high compared to PAOD and control groups (P<0.001 and P<0.001 respectively). Erythrocyte GSH and GSH-Px levels were significantly lower in patients with Buerger disease compared to patients with PAOD and controls (P<0.001 and P<0.001 respectively), while erythrocyte and plasma MDA levels were significantly higher (P<0.001 and P<0.001 respectively). CONCLUSION: It can be concluded that the levels of trace elments and toxic heavy metals and oxidative stress influence the disease process in Buerger disease more than PAOD.