The impact of COPD on polyneuropathy: results from the German COPD cohort COSYCONET.

BACKGROUND: Peripheral neuropathy is a common comorbidity in COPD. We aimed to investigate associations between alterations commonly found in COPD and peripheral neuropathy, with particular emphasize on the distinction between direct and indirect effects. METHODS: We used visit 4 data of the COPD cohort COSYCONET, which included indicators of polyneuropathy (repeated tuning fork and monofilament testing), excluding patients with diabetes a/o increased HbA1c. These indicators were analysed for the association with COPD characteristics, including lung function, blood gases, 6-min walk distance (6-MWD), timed-up-and-go-test (TUG), exacerbation risk according to GOLD, C-reactive protein (CRP), and ankle-brachial index (ABI). Based on the results of conventional regression analyses adjusted for age, BMI, packyears and gender, we utilized structural equation modelling (SEM) to quantify the network of direct and indirect relationships between parameters. RESULTS: 606 patients were eligible for analysis. The indices of polyneuropathy were highly correlated with each other and related to base excess (BE), ABI and TUG. ABI was linked to neuropathy and 6-MWD, exacerbations depended on FEV1, 6-MWD and CRP. The associations could be summarized into a SEM comprising polyneuropathy as a latent variable (PNP) with three measured indicator variables. Importantly, PNP was directly dependent on ABI and particularly on BE. When also including patients with diabetes and/or elevated values of HbA1c (n = 742) the SEM remained virtually the same. CONCLUSION: We identified BE and ABI as major determinants of peripheral neuropathy in patients with COPD. All other associations, particularly those with lung function and physical capacity, were indirect. These findings underline the importance of alterations of the micromilieu in COPD, in particular the degree of metabolic compensation and vascular status.

Cardiovascular Risk Factors in Cluster Headache.

Background: Patients with cluster headache tend to have a dysregulation of systemic blood pressure such as increased blood pressure variability and decreased nocturnal dipping. This pattern of nocturnal nondipping is associated with end-organ damage and increased risk of cardiovascular disease. Objective: To determine if cluster headache is associated with a higher risk of cardiovascular disease. Methods: Cross-sectional study of 33 cluster headache patients without evidence of cardiovascular disease and 30 age- and gender-matched healthy controls. Ambulatory blood pressure monitoring was performed in all subjects. We evaluate anthropometric, hematologic, and structural parameters (carotid intima-media thickness and ankle-brachial index). Results: Of the 33 cluster headache patients, 16 (48.5%) were nondippers, a higher percentage than expected. Most of the cluster headache patients (69.7%) also presented a pathological ankle-brachial index. In terms of the carotid intima-media thickness values, 58.3% of the patients were in the 75th percentile, 25% were in the 90th percentile, and 20% were in the 95th percentile. In the control group, only five of the 30 subjects (16.7%) had a nondipper pattern ( P = 0.004), with 4.54% in the 90th and 95th percentiles ( P = 0.012 and 0.015). Conclusions: Compared with healthy controls, patients with cluster headache presented a high incidence (48.5%) of nondipper pattern, pathological ankle-brachial index (69.7%), and intima-media thickness values above the 75th percentile. These findings support the hypothesis that patients with cluster headache present increased risk of cardiovascular disease.

Effectiveness of bedside investigations to diagnose peripheral artery disease among people with diabetes mellitus: a systematic review.

Non-invasive tests for the detection of peripheral artery disease (PAD) among individuals with diabetes mellitus are important to estimate the risk of amputation, ulceration, wound healing and the presence of cardiovascular disease, yet there are no consensus recommendations to support a particular diagnostic modality over another and to evaluate the performance of index non-invasive diagnostic tests against reference standard imaging techniques (magnetic resonance angiography, computed tomography angiography, digital subtraction angiography and colour duplex ultrasound) for the detection of PAD among patients with diabetes. Two reviewers independently screened potential studies for inclusion and extracted study data. Eligible studies evaluated an index test for PAD against a reference test. An assessment of methodological quality was performed using the quality assessment for diagnostic accuracy studies instrument. Of the 6629 studies identified, ten met the criteria for inclusion. In these studies, the patients had a median age of 60-74 years and a median duration of diabetes of 9-24 years. Two studies reported exclusively on patients with symptomatic (ulcerated/infected) feet, two on patients with asymptomatic (intact) feet only, and the remaining six on patients both with and without foot ulceration. Ankle brachial index (ABI) was the most widely assessed index test. Overall, the positive likelihood ratio and negative likelihood ratio (NLR) of an ABI threshold <0.9 ranged from 2 to 25 (median 8) and <0.1 to 0.7 (median 0.3), respectively. In patients with neuropathy, the NLR of the ABI was generally higher (two out of three studies), indicating poorer performance, and ranged between 0.3 and 0.5. A toe brachial index <0.75 was associated with a median positive likelihood ratio and NLRs of 3 and ≤ 0.1, respectively, and was less affected by neuropathy in one study. Also, in two separate studies, pulse oximetry used to measure the oxygen saturation of peripheral blood and Doppler wave form analyses had NLRs of 0.2 and <0.1. The reported performance of ABI for the diagnosis of PAD in patients with diabetes mellitus is variable and is adversely affected by the presence of neuropathy. Limited evidence suggests that toe brachial index, pulse oximetry and wave form analysis may be superior to ABI for diagnosing PAD in patients with neuropathy with and without foot ulcers. There were insufficient data to support the adoption of one particular diagnostic modality over another and no comparisons existed with clinical examination. The quality of studies evaluating diagnostic techniques for the detection of PAD in individuals with diabetes is poor. Improved compliance with guidelines for methodological quality is needed in future studies.

A service pathway for patients at risk of peripheral arterial disease.

Every year in the UK 100,000 people are diagnosed with peripheral arterial disease (PAD) (Belch at al, 2007). Those who are diagnosed are likely to suffer from cardiovascular complications and are six times more likely to die within 10 years, compared with people without PAD (Belch et al, 2007). This medical condition gives no symptoms at early stages and can develop manifesting itself through various degrees of intermittent claudication. This critical analysis will focus on the literature describing peripheral vascular problems with associated symptoms. It will also analyse current understanding of the quality of the vascular assessment within the primary care sector. As a natural consequence this piece of work will aim to highlight the role and significance of Healthcare Professionals within a new service pathway design for the community.

Utilization Rates of Diagnostic and Therapeutic Vascular Procedures Among Patients Undergoing Lower Extremity Amputations in a Rural Community Hospital: A Clinicopathological Correlation.

BACKGROUND: Significant geographical variations exist in amputation rates and utilization of diagnostic and therapeutic vascular procedures before lower extremity amputations in the United States. The purpose of this study was to evaluate the rates of diagnostic and therapeutic vascular procedures in the year prior to amputation in a contemporary population and correlate with pathological findings of the amputation specimens. METHODS: A retrospective analysis was conducted of non-traumatic amputations from 2011 to 2017 at a rural community hospital. We reviewed the proportion of patients undergoing diagnostic (ankle brachial index with duplex ultrasound, computerized tomography angiogram and invasive angiogram) and therapeutic (endovascular and surgical revascularization) vascular procedures in the year prior to amputation. Prevalence of tissue viability and osteomyelitis were evaluated in all amputated specimens and atherosclerotic vascular disease (ASVD) was evaluated in major amputations. We also analyzed primary amputation rates among different subgroups. RESULTS: 698 patients were included with 248 (36%) major amputations and 450 (64%) minor amputations. Any diagnostic procedure was performed in 59% of the major amputations and 49% of the minor amputations (P = 0.01). Any therapeutic revascularization procedure was performed in 34% of the major amputations and 28% of the minor amputations (P = 0.08). The pathology of major amputation specimens revealed severe ASVD in 57% and mild-moderate ASVD in 27% of specimens. Tissue viability was significantly higher in major amputations (90% vs 30%, P = 0.04) and osteomyelitis was significantly higher in minor amputations (50% vs 14%, P = 0.03). Primary amputations were performed in 66% of major amputations, 72% of minor amputations, 81% with mild to moderate ASVD and 54% with severe ASVD. CONCLUSION: Diagnostic and therapeutic vascular procedures appear under-utilized for patients undergoing lower extremity amputations at a rural community hospital. ASVD rates and tissue viability imply that revascularization could be of significant benefit to avoid major amputation.

Predictive value of brachial-ankle pulse wave velocity for long-term clinical outcomes after percutaneous coronary intervention in a Korean cohort.

OBJECTIVE: The aim of this study was to determine the associations of brachial-ankle pulse wave velocity (baPWV), high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-B type natriuretic peptide (NT-proBNP) with the development of adverse outcomes after percutaneous coronary intervention (PCI). METHODS: The baPWV, hs-cTnT and NT-proBNP were analyzed in 372 patients who underwent PCI. The primary endpoint was cardiac death. RESULTS: There were 21 events of cardiac death during a mean of 25.8 months of follow-up. When the baPWV cut-off level was set to 1672 cm/s using the receiver operating characteristic curve, the sensitivity was 85.7% and the specificity was 60.1% for differentiating between the group with cardiac death and the group without cardiac death. Kaplan-Meier analysis revealed that the higher baPWV group (≥1672 cm/s) had a significantly higher cardiac death rate than the lower baPWV group (<1672 cm/s) (11.4% vs. 1.4%, log-rank: P<0.0001). This value was more useful in patients with myocardial injury (hs-cTnT≥0.1 ng/mL) or heart failure (NT-proBNP≥450 pg/mL). CONCLUSIONS: The results of this study show that high baPWV is a predictive marker for cardiac death after PCI.

Thigh circumference and low ankle brachial index in US adults: results from the National Health and Nutrition Examination Survey 1999-2004.

OBJECTIVE: Recent studies have suggested that smaller thighs are a disadvantage for health and survival, but the association of thigh circumference with atherosclerosis remains uncertain. The purpose of this study was to investigate the association between thigh circumference and peripheral arterial disease (PAD), as measured by ankle brachial index (ABI). METHODS: This study used data from the National Health and Nutrition Examination Survey (1999-2004), in which participants' ABI and thigh circumference were measured simultaneously. A total of 5716 participants (2959 men and 2757 women) were included in the final analysis. A diagnosis of PAD was determined on the basis of ABI <0.9. RESULTS: The overall prevalence of PAD in this sample was 6.6%. Thigh circumference of those with PAD was 50.1cm compared to 52.2 cm for those without PAD (p < 0.0001). After adjusting for potential covariates, the prevalence of PAD generally decreased as thigh circumference increased up to 55 cm. In the first quantile (smallest thigh circumference), men and women had as much as a 4.8-fold (95% CI, 2.28-10.29) and a 3-fold (95% CI, 1.45-6.18) increased risk of PAD, respectively. Above 55 cm, PAD was no longer related to thigh circumference. CONCLUSIONS: Small thigh circumference may be associated with PAD, as measured by ABI.

Relationship of a low ankle-brachial index with all-cause mortality and cardiovascular mortality in Chinese patients with metabolic syndrome after a 6-year follow-up: a Chinese prospective cohort study.

OBJECTIVE: Peripheral arterial disease (PAD) is a common clinical manifestation of the systemic atherosclerotic process, and the ankle-brachial index (ABI) is an ideal tool to diagnose PAD. Currently, there have been few long-term follow-up studies focused on the associations of the ABI with all-cause mortality and cardiovascular disease (CVD) mortality in Chinese MetS patients. The aim of this study was to evaluate the usefulness of ABI to predict the prognosis of CVD in hospitalized Chinese patients with metabolic syndrome (MetS). METHODS: Participants from multi-center departments were followed up from November 2004 to January 2011. The study sample actually comprised 1,266 valid participants whose age was ≥35 years. Patients were separated into four groups, with an ABI ≤0.4, 0.41-0.7, 0.71-0.9 and 0.91-1.4. An ABI ≤0.9 was defined as PAD, and subjects with an ABI >1.4 were excluded because of the false negative rate. Factors related to all-cause and cardiovascular mortality were observed by Cox models and the log rank test. Potential confounding variables with values of p<0.10 were adjusted for the multivariate analysis. RESULTS: An abnormal ABI value was strongly, independently, and inversely correlated with the all-cause and cardiovascular mortality. After adjusting for age and other covariates, Cox models revealed that an abnormal ABI value was still correlated with the all-cause mortality (relative risk/RR/=1.82, 95% confidence interval/CI/=1.45-2.34 p<0.01), and CVD mortality (RR=1.88, 95% CI=1.51-2.90 p<0.01). CONCLUSION: An abnormal ABI value was not only a significant and independent risk factor for CVD, but also for the survival rate in Chinese MetS patients. Routine ABI evaluation could therefore be helpful for identifying high risk patients, especially MetS patients.