Ankle-brachial Index Categories Research Articles

Associations between physical activity and ankle-brachial index: the Swedish CArdioPulmonary bioImage Study (SCAPIS).

The ankle-brachial index (ABI) is the ratio of the ankle and brachial systolic blood pressures. In the clinical setting, low ABI (< 0.9) is an indicator of peripheral atherosclerosis, while high ABI (> 1.4) is a sign of arterial stiffness and calcification. The purpose of the current study was to investigate the association between ABI and physical activity levels, measured by accelerometer. The Swedish CArdioPulmonary bioImage Study (SCAPIS) is a Swedish nationwide population-based cross-sectional cohort for the study of cardiovascular and pulmonary diseases, in which individuals aged 50-64 years were randomly invited from the general population. The study population with data on ABI, physical activity, and sedentary time based on accelerometry was 27,737. Differences between ABI categories and associations to sedentary behavior, moderate to vigorous physical activity (MVPA), and other metabolic characteristics were compared. ABI was categorized as low, ABI ≤ 0.9, borderline, ABI 0.91-0.99, normal, ABI 1.0-1.39, and high, ABI ≥ 1.4. Prevalence of low ABI was higher in the most sedentary quartiles compared to the least sedentary (0.6% vs. 0.1%, p < 0.001). The most sedentary individuals also exhibited higher BMI, higher prevalence of diabetes and hypertension. The proportion of wake time spent in MVPA was lowest in those with low ABI (0.033 ± 0.004; p < 0.001) and highest in those with ABI > 1.4 (0.069 ± 0.001; p < 0.001) compared to those with normal ABI. Compared to normal ABI, the proportion of sedentary time was highest in those with low ABI (0.597 ± 0.012; p < 0.001) and lowest in those with ABI > 1.4 (0.534 ± 0.002; p = 0.004). This population-based study shows that middle-aged individuals with ABI > 1.4 have the highest level of physical activity, while individuals with a lower ABI, especially those with ABI < 0.9, are less active and spend more time sedentary. Future studies are needed to understand the relationships between ABI, physical activity, and the risk of peripheral arterial and cardiovascular disease in the general population.

Adherence to Supervised and Unsupervised Exercise Programmes in Ageing Population with Intermittent Claudication: A Randomized Controlled Trial.

Background: Intermittent Claudication symptomatic peripheral arterial disease (ICSPAD) is associated with reduced mobility, functional capacity, and quality of life. Physical exercise is an effective non-pharmacological intervention for the management of ICSPAD. Adherence to exercise programs is challenging, due to the nature of the disease and the complex comorbidities associated with it. This study aimed to determine adherence to three supervised physical exercise programs (a walking intervention, strength intervention, and concurrent intervention) and an unsupervised exercise program (standard advice) in individuals with ICSPAD. Methods: In this clinical trial, 122 patients were divided into four groups based on the type of exercise program they followed: standard advice, walking intervention, strength intervention, and concurrent intervention. Results: The results revealed that while the demographic characteristics were similar, the strength intervention group had a younger mean age, and the walking group had a higher prevalence of hypertension and increased usage of anti-hypertensive drugs. Adherence to physical exercise and pedometer wearing was highest in the standard advice group. Logistic regression analysis showed lower odds of adherence to exercise and pedometer wearing in the intervention groups compared to the standard advice group. Adherence did not significantly vary across ankle-brachial index categories. Furthermore, there was no significant difference in adherence between the severity levels of intermittent claudication, though mild cases tended to exhibit higher adherence. Conclusions: The results show that the standard advice from healthcare professionals positively influences treatment adherence.

Type 2 Diabetes Mellitus Status with Ankle-Brachial Index among Patients with Diabetic Foot Ulcer at Universitas Airlangga Hospital, Surabaya

Highlights: ABI was not influenced by diabetic status. A more severe form of diabetic ulcer was associated with a lower ABI value. Abstract Introduction: Diabetic foot ulcer (DFU) is one of the most significant complications of uncontrolled type 2 diabetes mellitus (T2DM) that may affect a patient’s prognosis and quality of life. This study aimed to identify the association between diabetic status, DFU severity, and other clinical factors with ankle-brachial index (ABI) score and category. Methods: This was a cross-sectional study under a consecutive sampling frame conducted for three months at Universitas Airlangga Hospital, Surabaya. Primary data for ABl were measured from T2DM patients with DFU in the Thoracic and Cardiovascular Polyclinic, while secondary clinical data were collected from the Department of Internal Medicine based on the inclusion and exclusion criteria specified in the patient's medical records. Results: Out of 30 included patients, 63.33% had uncontrolled diabetic status, and the average ABI score was 0.999 ± 0.19. DFU severity was significantly associated with the ABI score and ABI category. Patients indicated with angioplasty exhibited a markedly lower ABI score than those without (mean 0.32 vs 1.01; p &lt; 0.001). Indication of angioplasty was the only clinical factor significantly associated with a lower ABI score (p &lt; 0.001). Conclusion: Although the status of T2DM was unrelated to ABI, future research is recommended to advance the understanding of peripheral artery disease in diabetic foot ulcer patients.

The Cardiovascular-Mortality-Based Estimate for Normal Range of the Ankle-Brachial Index (ABI).

Background: The ankle–brachial index (ABI) is a first-line examination in cardiovascular risk evaluation. Since cut-off values for normal ABI vary, the aim of the present study was to identify the cardiovascular-mortality-based estimate for the normal range of the ABI. After determining the reference range for the ABI, the corresponding toe–brachial index (TBI) and toe pressure for normal ABI were analyzed. Methods: All consecutive non-invasive pressure measurements in the vascular laboratory of a large university hospital 2011–2013 inclusive were collected and combined with patient characteristics and official dates and causes of death. Patients with an ABI range of 0.8–1.4 on both lower limbs were included in this study. Results: From 2751 patients, 868 had bilateral ABI values within the inclusion. Both ABI category ranges 0.80–0.89 and 0.90–0.99 had poorer survival compared to ABI categories 1.00–1.29 (p < 0.05). The 1-, 3-, and 5-year cardiovascular-death-free survival for respective ABI categories 0.80–0.99 vs. 1.00–1.29 were 90% vs. 96%, 84% vs. 92%, and 60% vs. 87%. The 1-, 3-, and 5-year overall survival for ABI categories 0.80–0.99 vs. 1.00–1.29 were 85% vs. 92%, 75% vs. 83%, and 42% vs. 74%. Conclusions: Borderline ABI (0.90–0.99) associates with higher overall and cardiovascular mortality compared to ABI values 1.00–1.29.

Abstract 9703: Prevalence and Outcomes of Low Ankle Brachial Index in ASCVD Risk Categories- from the National Health and Nutrition Examination Survey

Introduction: The utility of Ankle Brachial Index(ABI) as a risk-enhancer to the pooled cohort equations(PCE) in assessing cardiovascular risk for primary prevention of atherosclerotic cardiovascular disease(ASCVD) is uncertain. We aim to assess the prevalence and all-cause mortality of people with low ABI across ASCVD risk categories. Hypothesis: Would the addition of ABI to standard ASCVD risk assessment improve all cause mortality risk stratification? Methods: Participants were recruited as part of the National Health and Nutrition Examination Survey from 1999-2004 and mortality assessed on 12/31/2015. We included participants aged 40-75years with ABI values≤1.3 and data for ASCVD computation using the PCE. Persons with ABI&lt;0.9 and ABI 0.9-1.3 were classified as having low ABI and normal ABI, respectively. Results: The mean follow-up time was 156months(95%CI 154-158). Persons with low ABI were older(61 Vs 53years) and had higher mean systolic blood pressure(135 Vs 126mmHg). There was no difference in mean total cholesterol(mg/dl)[212(95%CI 210-214) vs. 208( 202-215)], LDL(mg/dl) [128 (95%CI 125-130) vs. 121(112-129)] and HDL(mg/dl) [54 (95%CI 53-54) vs. 52(50-55)] between the two ABI categories. The all-cause mortality was higher among persons with low ABI(43.1%) compared to those with normal ABI(12.2%), p&lt;0.001. The all-cause mortality in the normal ABI and low ABI categories was 4.8% and 8.8% in the low risk ASCVD group and 7.8% and 41.6% in the borderline/intermediate ASCVD risk group, respectively. Conclusions: Approximately 67% of participants with low ABI were classified as low, borderline or intermediate risk by PCE. Low ABI was associated with increased all-cause mortality in the intermediate/borderline and high ASCVD risk categories but not in the low ASCVD risk category. Our study supports the use of ABI in risk stratification for primary prevention of ASCVD in individuals with borderline or intermediate risk.

Abstract P007: Ankle-brachial Index And Cardiovascular Outcomes In Older Adults: The Atherosclerosis Risk In Communities Study

Introduction: The ankle-brachial index (ABI) is a representative diagnostic indicator of peripheral artery disease (PAD) and recognized as a risk enhancer in the ACC/AHA guidelines for primary prevention of atherosclerotic cardiovascular disease (ASCVD). However, our understanding of the association between ABI and cardiovascular (CVD) risk in older adults is limited. Additionally, the prognostic value of ABI among individuals with prior ASCVD is not well understood. Hypothesis: In a contemporary cohort of older adults, low ABI is independently associated with higher risk of CVD events, regardless of prevalent ASCVD at baseline (coronary heart disease [CHD], stroke, and/or symptomatic PAD). Methods: At ARIC Visit 5 (2011-2013), we studied 5,005 participants (4,160 without prior ASCVD [median age 74 years, 38% male], and 843 with ASCVD [median age 76 years, 65% male]). We quantified the association between ABI categories and subsequent risk of heart failure (HF) and composite CHD/stroke using multivariable Cox proportional hazards models. Results: Over a median follow-up of 5.5 years, we observed 400 CHD/stroke and 338 HF cases (242 CHD/stroke and 199 HF cases in those without prior ASCVD). After adjustment for CVD risk factors, in those without ASCVD history, ABI ≤0.9 was associated with a higher risk of both CHD/stroke and HF ( Table ). In those with a history of ASCVD, low ABI was not significantly associated with CHD/stroke, but was associated with HF (hazard ratio 7.1, 95% CI: 2.5-20.5); ABI categories of 0.9-1.1 and &gt;1.3 were also significantly associated with HF. Addition of ABI to traditional risk factors improved prediction of CHD/stroke risk in those without prior ASCVD and prediction of HF, regardless of baseline ASCVD ( Table ). Conclusions: Low ABI (≤0.9) was associated with incident CHD/stroke in those without prior ASCVD and HF regardless of baseline ASCVD status. These results support ABI as a risk enhancer for guiding primary prevention of ASCVD and suggest its potential value in HF risk assessment for older adults.

Prognostic Value of Abnormal Ankle-Brachial Index in Patients With Coronary Artery Disease: A Meta-Analysis.

The prognostic value of the ankle-brachial index (ABI) in patients with coronary artery disease (CAD) remains undefined. This meta-analysis sought to investigate the association of abnormal ABI and adverse outcomes in patients with CAD. PubMed, Embase, China National Knowledge Infrastructure, VIP, and Wanfang databases were comprehensively searched for studies published from inception to September 10, 2019. All observational studies investigating the association of abnormal baseline ABI and risk of major adverse cardiovascular events (MACE) or all-cause mortality were selected. Normal ABI is usually defined as between 0.9 and 1.4. The prognostic values were summarized by pooling risk ratio (RR) with 95% confidence intervals (CIs) for abnormal versus normal ABI category. Nine (9384 patients with CAD) studies were included. Abnormal ABI was independently associated with MACE (RR: 2.46; 95% CI: 2.02-2.99) and all-cause mortality (RR: 1.74; 95% CI: 1.32-2.30). Subgroup analysis showed that the pooled RR for MACE was 2.34 (95% CI: 1.73-3.16) for an abnormal low ABI. Abnormal ABI predicts MACE and all-cause mortality in patients with CAD, even after adjusting conventional confounding factors. However, the prognostic value of abnormal ABI is mainly dominated by a low ABI rather than a high ABI.

Levels of ankle–brachial index and the risk of diabetes mellitus complications

ObjectiveWe sought to compare the association of categorized ankle–brachial index (ABI) with mortality and complications of diabetes in persons with no symptoms of peripheral arterial disease (PAD) and in primary...

Correlation Between Ankle Brachial Index and Lower Limbs Digital Pulse Oximetry: A Referral Center Experience, Prevalence Study

ObjectiveAnkle-brachial index (ABI) is widely recommended and used to evaluate peripheral arterial disease. The oxygen saturation (SpO2) has been associated with ABI, showing a promising clinical practice utility; however, little literature regarding this matter has been reported. This study aims to assess the correlation between pulse oximetry and ABI. MethodsA cross-sectional study was conducted using ABI measuring devices, such as the MESI® Ankle Brachial Pressure Index (ABPI) (MESI, Ltd., Slovenia, EU) and pulse oximetry. We compared the SpO2 distribution by using the Wilcoxon test and evaluated its correlation by using logistic regression. ResultsFrom a total of 86 patients, 54 were males (62.8%) and the median age was 54 years old (interquartile range (IQR) = 37 - 65 yrs.). Regarding ABI measurements of the right lower limb (RLL), a total of 20 patients (22.3%) had an abnormal classification. On the other hand, a total of 21 patients (22.1%) had an abnormal classification of the left lower limb (LLL) ABI measurements. The distribution of SpO2 in relation to ABI categories was not statistically different (RLL p = 0.2433; LLL p = 0.1242). The SpO2 classification of ABI and abnormal pulse oximetry for the RLL was at 76.7% and at 77.9% in the LLL (Pearson’s goodness-of-fit test: RLL = p < 0.001 and LLL = p < 0.001). ConclusionAlthough we didn’t observe any statistical differences in the SpO2 distribution regarding ABI measurements, in their correlation, there seems to be a different tendency. The SpO2 might be a useful non-invasive tool to assess asymptomatic patients with risk factors for peripheral arterial disease (PAD).

Impact of Body Mass Index on the Association of Ankle-Brachial Index With All-Cause and Cardiovascular Mortality: Results from the National Health and Nutrition Examination Survey.

ObjectiveTo assess the influence of body-mass index (BMI) on the association of ankle-brachial index (ABI) with mortality.Patients and MethodsWe conducted a prospective study of National Health and Nutrition Examination Survey participants enrolled from January 1, 1999 to December 31, 2002 with BMI and ABI data available. ABI categories were <0.9 (low), 0.9 to 1.3 (reference), and >1.3 (high). BMI categories were <30 kg/m2 (nonobese) and ≥30 kg/m2 (obese). Cardiovascular (CV) and all-cause mortality were assessed by National Death Index records. Cox proportional-hazards models and Kaplan-Meier survival estimates were used to compare groups.ResultsIn total, 4614 subjects were included, with mean age 56±12 years and BMI 28±6 kg/m2. Median follow-up was 10.3 years (interquartile range [IQR]: 9.3 to 11.4 years). Low and high ABI were present in 7% and 8%, respectively. After adjustment, low ABI was associated with increased all-cause and CV mortality in nonobese (hazard ratio [HR] 1.5, 95% CI, 1.1-2.1 for all-cause and 3.0 [1.8-5.1] for CV mortality) and obese individuals (1.8 [1.2-2.7] and 2.5 [1.2-5.6], respectively) compared with reference. High ABI was associated with increased CV mortality in nonobese (2.2 [1.1-4.5]) but not obese patients; it was not associated with all-cause mortality overall or when stratified by BMI.ConclusionIn a US cohort, weight influenced the prognostic significance of high ABI. This may be related to technical factors reducing compressibility of the calf arteries in obese persons compared with those who are nonobese.

472-P: Associations between Ankle Brachial Index, Diabetes, and Sleep Apnea: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) Database

Introduction: Sleep apnea and diabetes mellitus (DM) negatively impact cardiovascular health. One important indicator of cardiovascular health is the Ankle-Brachial Index (ABI). Either low (LABI) or high (HABI) are signs of peripheral vascular impairment. Impaired vascular health and DM, together, might provoke sleep apnea; however, information regarding these relationships is limited. Therefore, this study aimed to investigate the association between ABI, DM status, and severity of sleep apnea in people of Hispanic/Latino descent. Methods: A cross sectional analysis from a multi-center epidemiologic study, HCHS/SOL‎, was utilized, including 8,378 participants (mean age 45.92?±?13.96, female = 49%, mean BMI=30.06?±?5.55). The sample was divided into 6 groups based on ADA guidelines (no-DM or DM) and ABI categories (LABI, normal ABI, or HABI). A linear regression was used to determine the strength of association between groups to predict the severity of sleep apnea, measured by the Apnea-Hypopnea Index (AHI). A Kruskal-Wallis H test was used for AHI comparisons between groups. Significance level was set at 0.01. Results: There were significant differences between groups for mean AHI (P&amp;lt;0.001; no-DM+normal ABI= 19.28±16.57, DM+normal ABI = 26.85?±?21.87, no-DM+LABI = 17.63?±?18.22, DM?+LABI = 26.31?±?21.62, no-DM?+HABI = 27.12?±?19.82, and DM?+HABI = 33.0?±?22.01). Linear regression ?showed that DM and HABI was significantly associated with severe sleep apnea (β= 5.7, p=0.007) after controlling for age, waist-hip ratio, and Statin medication. Conclusion: ?These data suggest that ?people with DM and HABI were more likely to have severe apnea compared to the other groups. People with DM, HABI, and severe sleep apnea might be at higher risk of cardiovascular complications. Thus, further research is required to elucidate the appropriate intervention to combat the high level of Peripheral artery disease. Disclosure M.M. Alshehri: None. A.S. Alqahtani: None. A.M. Alenazi: None. S. Alothman: None. M. Aldhahi: None. C.M. Gray: None. B. Alqahtani: None. P. Kluding: None.

Ankle-Brachial Index is a Predictor of Future Incident Chronic Kidney Disease in a General Japanese Population.

Aims: The ankle-brachial index (ABI) can be a prognostic marker for chronic kidney disease (CKD) in Western populations. Since there is little relevant evidence for Asian populations, we investigated the relationship between ABI and the risk of incident CKD in a general Japanese population.Methods: The cohort included 5,072 participants aged 30–79 without a history of renal disease or cerebro-cardiovascular disease. Incident CKD, defined as an estimated glomerular filtration rate < 60 (mL/min/1.73 m2) and/or proteinuria (≥ 1 + on urine dipstick), was compared among participants grouped according to baseline ABI: 0.90–0.99, 1.00–1.09, 1.10–1.19, 1.20–1.29, and 1.30–1.39. Hazard ratios for incident CKD were estimated using a Cox proportional hazards model, with the ABI 1.10–1.19 group serving as the reference.Results: The CKD incidence rate (/100 person-years) was 1.80 during the mean follow-up period of 5.1 years. The CKD incidence rate was 3.04 in the ABI category 0.90–0.99, 1.58 in ABI 1.00–1.09, 1.72 in ABI 1.10–1.19, 2.01 in ABI 1.20–1.29, and 3.33 in ABI 1.30–1.39. The hazard ratios for developing CKD were 2.14 (95% confidence interval 1.16–3.92) in ABI 0.90–0.99, 1.08 (0.83–1.41) in ABI 1.00–1.09, 1.03 (0.83–1.29) in ABI 1.20–1.29, and 1.37 (0.77–2.47) in ABI 1.30–1.39, after adjusting for age, sex, systolic blood pressure, diabetes, and other confounding factors.Conclusions: In a general Japanese population, an ABI of 0.90–0.99 was associated with an increased risk of incident CKD, independent of traditional cardiovascular risk factors.

Abstract 722: Evaluation of Peripheral Calcium Score as a Measure of Peripheral Artery Disease Severity

The current gold standard for diagnosing PAD is Ankle Brachial Index (ABI). However, vascular calcification can falsely elevate ABI. No studies have compared the diagnostic value of peripheral calcium score (PCS) in lower extremity arteries with ABI. Primary aim of this study was to describe the association of PCS with continuous ABI values and categories of ABI in a retrospective cohort design. We identified 50 patients who underwent CTA and ABI measurements [ABI categories for PAD severity: severe (&lt;0.5), moderate (0.5-0.9), normal (0.9-1.4), noncompressible (&gt;1.4)]. We evaluated CTAs imaged from abdominal aorta through lower extremities and determined total calcium volume of plaques with density &gt;130 HU and area &gt;1mm 2 from infrarenal abdominal aorta to the foot using TeraRecon by two independent readers (Intra class correlation 99%). We explored the association between ABI and PCS in SAS using multiple linear regression and analysis of covariance adjusting for age, race, smoking status, hypertension, hyperlipidemia, type II diabetes, and chronic kidney disease. We found that ABI was inversely associated with PCS in linear regression (p&lt;0.01, Figure 1A). Differences in mean PCS were statistically significant across ABI categories [F(3,29)= 5.03, p=0.01, Figure 1B]. Across subgroups, the mean PCS was significantly different for ABIs &lt;0.5 and 0.5-0.9 (p=0.02), &lt;0.5 and &gt;1.4 (p&lt;0.001), 0.5-0.9 and &gt;1.4 (p=0.04), 0.9-1.4 and &gt;1.4 (p=0.05). Proportion of tibial calcium to overall PCS was much lower in ABI&lt;0.5: 0.0003 vs ABI&gt;1.4: 0.357 (p=0.02). Mean PCS may be a valid measure of PAD severity and percentage of tibial calcium may help quantify PAD burden in non-compressible vessels. Our study serves as proof of concept for a comprehensive PCS system to diagnose and evaluate PAD severity, particularly in high-risk subpopulations where non-invasive studies may be unreliable.

Abnormal ankle-brachial index and risk of cardiovascular or all-cause mortality in patients with chronic kidney disease: a meta-analysis.

Prognostic role of ankle-brachial index (ABI) in patients with chronic kidney disease (CKD) is controversial. We aimed to evaluate whether abnormal ABI was an independent predictor of cardiovascular or all-cause mortality in CKD patients with or without hemodialysis by conducting a meta-analysis. We systematically searched Pubmed and Embase databases for prospective observational studies that investigated baseline abnormal ABI and subsequent cardiovascular or all-cause mortality risk in CKD patients with or without hemodialysis. An ABI value of 0.9 to 1.3 was defined as normal. Pooled hazard risk (HR) with 95% confidence interval (CI) was calculated for the abnormal vs. normal ABI category. Six studies enrolling 5820 patients were identified and analyzed. Overall, abnormal ABI was associated with an increased risk of all-cause mortality (HR 2.26; 95% CI 1.60-3.18) and cardiovascular mortality (HR 3.58; 95% CI 2.53-5.06). Subgroup analysis indicated that patients with abnormally low ABI increased by 2.45-fold all-cause mortality and 5.18-fold cardiovascular mortality. Similarly, an abnormally high ABI increased by 1.94-fold all-cause mortality and 4.04-fold cardiovascular mortality. In addition, the effect of abnormal ABI on all-cause mortality was more pronounced among hemodialysis patients (HR 3.06; 95% CI 2.30-4.07) but not in CKD patients (HR 1.42; 95% CI 0.98-2.05). Abnormally low and high ABI are independently associated with cardiovascular or all-cause mortality risk in maintenance hemodialysis patients. This meta-analysis highlighted an U-shaped relationship between ABI and mortality risk in CKD patients undergoing hemodialysis. However, findings of this meta-analysis were undermined by the small number of included studies.

Abstract 13925: Association of Ankle-Brachial Index With Incident Atrial Fibrillation: The Atherosclerosis Risk in Communities (ARIC) Study

Introduction: A normal ankle-brachial index (ABI) is defined as 1.0 to 1.4; abnormal ABI is defined as ≤0.90 whereas &gt;0.9 to &lt;1.0 is considered “borderline” and &gt;1.40 indicates noncompressible arteries. Although peripheral arterial disease has been shown to be associated with incident AF, it is unclear whether borderline ABI or noncompressible arteries are associated with incident AF. We aimed to evaluate this association of borderline ABI and ABI &gt;1.4 in the ARIC study, a population-based prospective cohort study. Methods: We included 14,794 participants (age, 54.2 ± 5.8 yrs, 55% women, 26% blacks) who attended the baseline exam (1987-89) and without prevalent AF. Incident AF was identified from hospital discharge records, death certificates, and ECGs. We used Cox proportional hazard models to evaluate the association between ABI categories and incident AF. Results: During a mean follow-up of 19.8 years, there were 2288 incident AF cases. After full adjustment in Model 2, compared with ABI 1.0-1.4, the hazards ratio (HR) (95% CI) of ABI &lt;1.0 for incident AF was 1.13 (1.01-1.27). ABI of &gt;0.9 to &lt;1.0, but not &gt;1.4 was associated with an increased risk of AF (Table). Conclusions: This study is the first to show that borderline ABI is independently associated with AF further supporting that borderline ABI is not benign. Our findings also suggest that detection of preclinical and early clinical atherosclerosis may identify individuals at increased risk of AF.

Elevated Levels of Adhesion Proteins Are Associated With Low Ankle-Brachial Index.

Inflammation plays a pivotal role in peripheral artery disease (PAD). Cellular adhesion proteins mediate the interaction of leukocytes with endothelial cells during inflammation. To determine the association of cellular adhesion molecules with ankle-brachial index (ABI) and ABI category (≤1.0 vs >1.0) in a diverse population, 15 adhesion proteins were measured in the Multi-Ethnic Study of Atherosclerosis (MESA). To assess multivariable associations of each protein with ABI and ABI category, linear and logistic regression was used, respectively. Among 2364 participants, 23 presented with poorly compressible arteries (ABI > 1.4) and were excluded and 261 had ABI ≤ 1.0. Adjusting for traditional risk factors, elevated levels of soluble P-selectin, hepatocyte growth factor, and secretory leukocyte protease inhibitor were associated with lower ABI ( P = .0004, .001, and .002, respectively). Per each standard deviation of protein, we found 26%, 20%, and 19% greater odds of lower ABI category ( P = .001, .01, and .02, respectively). Further investigation into the adhesion pathway may shed new light on biological mechanisms implicated in PAD.

Co-existence of vascular disease in different arterial beds: Peripheral artery disease and carotid artery stenosis--Data from Life Line Screening(®).

Atherosclerosis is a systemic vascular disorder, involving multiple arterial territories. This project sought to investigate the relationship between lower extremity peripheral artery disease (PAD) and carotid artery stenosis (CAS) in a large self-referred population. Data from the ankle brachial index (ABI) and carotid duplex ultrasound were analyzed from 3.67 million US subjects in the Life Line Screening program between 2004 and 2008. PAD was defined by ABI<0.9 and CAS was defined by greater than 50% stenosis. Multivariate logistic regression analysis was used to estimate odds of CAS by PAD status and severity. Mean age of the population was 63.7±10.6 years and 64% were women. The prevalence of PAD and CAS was 4.1% and 3.9%, respectively. Subjects with PAD had a higher prevalence of CAS than those without PAD (18.8% vs. 3.3%, P<0.0001). In multivariate analysis, PAD was associated with greater odds of CAS (OR 3.28, 95% CI 3.22-3.34). Both symptomatic (OR 3.66, 95% CI 3.58-3.75) and asymptomatic PAD (OR 2.91, 95% CI 2.84-2.98) was associated with CAS. Increasing severity of PAD was associated with greater odds of CAS (OR 2.32, 3.61, 4.19, 5.14, and 7.59 for ABI categories 0.81-0.90, 0.71-0.80, 0.61-0.70, 0.41-0.60, ≤0.40, respectively). Presence and severity of PAD was associated with prevalence of CAS in the large self-referred and self-paying Life Line cohort, regardless of lower extremity symptoms.

Low ankle-brachial index is associated with early-stage chronic kidney disease in type 2 diabetic patients independent of albuminuria.

AimsThe role of low ankle-brachial index (ABI) in early-stage chronic kidney disease (CKD) is not fully known. This study was designed to investigate the prevalence of low ABI in early-stage CKD defined as an estimated glomerular filtration rate (eGFR) between 60–89 ml/min/1.73 m2 of type 2 diabetic patients without albuminuria and to determine the association between the low ABI and mildly decreased eGFR.MethodsThe cross-sectional study enrolled 448 type 2 diabetic patients with normoalbuminuria. The patients were stratified into two groups according to the CKD-EPI eGFR level: the normal group with eGFR level ≥90 mL/min/1.73 m2 and the lower group with eGFR of 60–89. ABI was categorized as normal (1.0–1.39), low-normal (0.9–0.99), and low (<0.9). Both stepwise forward multiple linear regression and binary logistic regression analyses were performed to examine the association between ABI categories and eGFR levels and to assess the relation of low ABI and early-stage CKD.ResultsThe prevalence of low ABI in early-stage CKD of type 2 diabetic patients without albuminuria was 39.5%. Low ABI was associated with an approximate 3-fold greater risk of early-stage CKD in bivariate logistic regression analysis, and remained significantly associated with a 2.2 fold risk (95% confidence interval: 1.188–4.077; P = 0.012) after adjusting traditional chronic kidney disease risk factors.ConclusionsThere was a high prevalence of low ABI in early-stage CKD patients of type 2 diabetes with normoalbuminuria and a close relation between low ABI and early-stage CKD, suggesting that we should pay much more attention to the patients who have only mildly decreased eGFR and normoalbuminuria but have already had a low ABI in clinic work and consider the preventive therapy in early stage.

Biomarkers of inflammation may be of use for identification of more severe peripheral arterial occlusive disease

Background:Atherosclerosis is a multifactorial disease with an inflammatory pathophysiological basis. Cytokines released during the atherosclerotic process induce production of C-reactive protein (CRP) in the liver, which is an important marker of inflammation.Objective:We tested whether inflammatory biomarkers were associated with deterioration of peripheral arterial occlusive disease (PAOD) in a population at high cardiovascular risk.Methods:1,330 subjects ≥30 years of age underwent clinical and laboratory examinations as part of a population-based study of the prevalence of diabetes. PAOD was defined as an ankle-brachial index (ABI) ≤0.90. After application of exclusion criteria, the sample comprised 1,038 subjects. Traditional risk factors, CRP and interleukin 6 (IL-6) were also compared across three ABI categories (≤0.70; 0.71-0.90; ≥0.90). Mean values for these variables were compared by presence/absence of DAOP (Student's t test) and by ABI categories (ANOVA). Poisson regression and logistic regression models were used to test for associations between risk factors and DAOP and between risk factors and the ABI categories. Pearson's linear correlation coefficients were calculated for the relationship between CRP and IL-6 levels.Results:Mean age was 56.8±12.9 years, 54% of the sample were women and the prevalence of DAOP was 21.0% (95%CI 18.4-24.1). Individuals with ABI ≤0.70 had higher concentrations of CRP-us (2.1 vs. 1.8) and of IL-6 (1.25 vs. 1.17). Concentrations of CRP and IL-6 were only correlated in patients with DAOP, (p=0.004).Conclusions:The finding that CRP and IL-6 levels were only elevated among people with advanced DAOP may suggest that these biomarkers have a role to play as indicators of more severe disease. Prospective studies are needed to test this hypothesis.

Ankle-brachial index, toe-brachial index, and cardiovascular mortality in persons with and without diabetes mellitus

The prognostic utility of the ankle-brachial index (ABI) may be hampered in persons with diabetes due to peripheral arterial stiffening in the ankles. Stiffening of toe arteries occurs infrequently in diabetes. We aimed to determine the nature of the relationship of the toe-brachial index (TBI) and ABI with cardiovascular disease (CVD) mortality and to determine whether the associations are modified in individuals with diabetes. Individuals with clinically suspected atherosclerotic peripheral arterial disease who underwent ABI and TBI measurements in a vascular laboratory were monitored longitudinally for CVD mortality. Among 469 participants (89% men), the mean age was 68 ± 9 years, and 36% had diabetes. The mean ABI was 0.83 ± 0.28 and the mean TBI was 0.60 ± 0.24. During median 7.0 years of follow-up, there were 158 CVD deaths. The association of the ABI categories with CVD deaths differed in diabetic vs nondiabetic participants (P = .002 for interaction). In contrast, the association of the TBI categories with CVD deaths was similar, irrespective of diabetes status (P = .17 for interaction). Among diabetic patients, a U-shaped relationship was observed between ABI categories and CVD death: those with low (<0.90) and high (>1.30) ABIs were both at higher risk than those with normal ABIs (range, 0.90-1.30). In nondiabetic patients, association of ABI categories with CVD death was linear, such that those with an ABI >1.30 were at the lowest risk, whereas those with an ABI <0.90 were at higher risk. In contrast, the association of TBI categories with CVD death was linear irrespective of diabetes status. High TBI categories consistently predicted low risk, whereas risk was higher with progressively lower TBI categories. Among diabetic individuals with clinically suspected peripheral arterial disease, those with low and high ABIs are both at higher risk of CVD death. In contrast, a linear relationship was observed between TBI categories and CVD death irrespective of diabetes status. These findings suggest that stiffened ankle arteries may limit the predictive value of the ABI in individuals with diabetes, a limitation that may be overcome by measurement of the TBI.