Association of ankle-brachial index level with stroke

Dose-Response Association of Low and Normal Ankle Brachial Index With the Risk of Cardiovascular Disease Morbidity and Mortality

We quantitatively evaluated the dose-response association of low and normal ankle brachial index (ABI) with the risk of morbidity and mortality from cardiovascular diseases (CVDs). PubMed, Embase, and Web of Science were systematically searched for cohort studies. Random effects or fixed effects models were used to estimate the pooled relative risks (RRs) and 95% confidence intervals (95% CIs). Generalized least squares regression was used to assess study-specific dose-response associations per 0.1 ABI decrease. Restricted cubic splines were used to evaluate linear or nonlinear trends. Twelve cohort studies (57 031 participants) were included in this meta-analysis. For low vs normal ABI levels, the pooled RRs were 2.03 (95% CI, 1.72-2.41; I² = 52.9%; p_{heterogeneity}=0.030) and 2.29 (95% CI, 1.98-2.64; I² = 39.5%; p_{heterogeneity} =0.158) for CVD morbidity and CVD mortality, respectively. For per 0.1 ABI decrease from 1.40 the risk for CVD morbidity and CVD mortality increased by 8% (1.08, 95% CI 1.04-1.11) and 11% (1.11, 95% CI 1.07-1.15), respectively. Restricted cubic splines showed inverse linear associations for CVD morbidity and CVD mortality. As a non-invasive index, lower ABI was significantly associated with the increased risk of morbidity and mortality from CVDs in an inverse linear manner.

Prevalence of Lower Extremity Arterial Disease as Measured by Low Ankle-Brachial Index in Patients with Acute Cerebral Ischemic Events

BACKGROUND

Low ankle-brachial index (ABI) of ≤0.9 is diagnostic of lower extremity arterial disease (LEAD). It is also a strong marker of generalized atherosclerosis. The objective of this study was to assess the prevalence of low ABI in patients with acute cerebral ischemic events (ACIE): ischemic stroke (IS) or transient ischemic attack (TIA).

METHODS

We compared 150 inpatients with ACIE to 50 inpatient controls and assessed risk factors, ABI measurements, and Duplex ultrasound of the cervical vessels.

RESULTS

Low ABI was seen in 69 patients (46%) in the ACIE group and in 8 (16%) in the control group; p < 0.01. The mean and median ABI values in the ACIE group were 0.88 (SD = 0.22) and 0.91 (0.24-1.33), which were significantly lower than in the control group: 1.04 (SD = 0.16) and 1.0 (0.66-1.36); p < 0.0001, respectively. Coronary artery disease, carotid stenosis of ≥50% and smoking were risk factors, which were associated with significantly lower ABI in the study group; the ABI with risk factors vs. without was 0.85 vs. 0.92 (coronary artery disease); p < 0.05, 0.7 vs. 0.92; (carotid stenosis) p < 0.001 and 0.83 vs. 0.98; (smoking) p < 0.001, respectively.

CONCLUSION

Our study demonstrated that patients with ACIE have significantly higher involvement of another vascular bed as LEAD. Coronary artery disease, carotid stenosis ≥50% and smoking were main risk factors associated with coexistence of LEAD and ACIE.

Ankle brachial index and cognitive function among Hispanics/Latinos: Results from the Hispanic Community Health Study/Study of Latinos

BACKGROUND AND AIMS

The Ankle-Brachial index (ABI) is a well-accepted measure of peripheral artery disease (arterial stenosis and stiffness) and has been shown to be associated with cognitive function and disorders; however, these associations have not been examined in Hispanics/Latinos. Therefore, we sought to examine relationships between ABI and cognitive function among diverse middle-age and older Hispanics/Latinos.

METHODS

We used cross-sectional data on n = 7991 participants aged 45-74 years, without stroke or coronary heart disease, from the Hispanic Community Health Study/Study of Latinos. Our primary outcome, global cognition (GC), was a continuous composite score of four cognitive domains (verbal learning and memory, verbal fluency, executive function, and mental status). Secondary outcomes were the individual tests representing these domains. The ABI was analyzed continuously and categorically with standard clinical cut-points. We tested associations using generalized survey regression models incrementally adjusting for confounding factors. Age, sex, hypertension, diabetes, and dyslipidemia moderations were examined through interactions with the primary exposure.

RESULTS

In age, sex, and education adjusted models, continuous ABI had an inverse u-shape association with worse GC. We found similar associations with measures of verbal learning and memory, verbal fluency, executive function, but not with low mental status. The associations were attenuated, but not completely explained, by accounting for the confounders and not modified by age, sex, education, and vascular disease risks.

CONCLUSIONS

In addition to being a robust indicator of arterial compromise, our study suggests that abnormal ABI readings may also be useful for early signaling of subtle cognitive deficits.

Color Doppler Ultrasonography Is a Useful Tool for Diagnosis of Peripheral Artery Disease in Type 2 Diabetes Mellitus Patients with Ankle-Brachial Index 0.91 to 1.40

BACKGROUND

The clinical utility of ankle-brachial index (ABI) is not clear in subjects with less severe or calcified vessel. Therefore, we investigated the usefulness of color Doppler ultrasonography for diagnosing peripheral artery disease (PAD) in type 2 diabetes mellitus (T2DM) subjects.

METHODS

We analyzed 324 T2DM patients who concurrently underwent ABI and carotid intima-media thickness (CIMT) measurements and color Doppler ultrasonography from 2003 to 2006. The degree of stenosis in patients with PAD was determined according to Jager's criteria, and PAD was defined as grade III (50% to 99% stenosis) or IV stenosis (100% stenosis) by color Doppler ultrasonography. Logistic regression analysis and receiver operating characteristic curve analysis were performed to evaluate the risk factors for PAD in patients with ABI 0.91 to 1.40.

RESULTS

Among the 324 patients, 77 (23.8%) had ABI 0.91 to 1.40 but were diagnosed with PAD. Color Doppler ultrasonography demonstrated that suprapopliteal arterial stenosis, bilateral lesions, and multivessel involvement were less common in PAD patients with ABI 0.91 to 1.40 than in those with ABI ≤0.90. A multivariate logistic regression analysis demonstrated that older age, current smoking status, presence of leg symptoms, and high CIMT were significantly associated with the presence of PAD in patients with ABI 0.91 to 1.40 after adjusting for conventional risk factors. CIMT showed significant power in predicting the presence of PAD in patients with ABI 0.91 to 1.40.

CONCLUSION

Color Doppler ultrasonography is a useful tool for the detection of PAD in T2DM patients with ABI 0.91 to 1.40 but a high CIMT.

Impressive predictive value of ankle-brachial index for very long-term outcomes in patients with cardiovascular disease: IMPACT-ABI study

Background

The ankle—brachial index (ABI) is a marker of generalized atherosclerosis and is predictive of future cardiovascular events. However, few studies have assessed its relation to long-term future cardiovascular events, especially in patients with borderline ABI. We therefore evaluated the relationship between long-term future cardiovascular events and ABI.

Methods

In the IMPACT-ABI study, a single-center, retrospective cohort study, we enrolled 3131 consecutive patients (67 ± 13 years; 82% male) hospitalized for cardiovascular disease and measured ABI between January 2005 and December 2012. After excluding patients with an ABI > 1.4, the remaining 3056 patients were categorized as having low ABI (≤ 0.9), borderline ABI (0.91–0.99), or normal ABI (1.00–1.40). The primary endpoint was MACE (cardiovascular death, myocardial infarction [MI] and stroke). The secondary endpoints were cardiovascular death, MI, stroke, admission due to heart failure, and major bleeding.

Results

During a 4.8-year mean follow-up period, the incidences of MACE (low vs. borderline vs. normal: 32.9% vs. 25.0% vs. 14.6%, P<0.0001) and cardiovascular death (26.2% vs. 18.7% vs. 8.9%, P<0.0001) differed significantly across ABIs. The incidences of stroke (9.1% vs. 8.6% vs. 4.8%, P<0.0001) and heart failure (25.7% vs. 20.8% vs. 8.9%, P<0.0001) were significantly higher in the low and borderline ABI groups than in the normal ABI group. But the incidences of MI and major bleeding were similar in the borderline and normal ABI groups. The hazard ratios for MACE adjusted for traditional atherosclerosis risk factors were significantly higher in patients with low and borderline ABI than those with normal ABI (HR, 1.93; 95%CI: 1.44–2.59, P < 0.0001, HR, 1.54; 95% CI: 1.03–2.29, P = 0.035).

Conclusions

The incidence of long-term adverse events was markedly higher among patients with low or borderline ABI than among those with normal ABI. This suggests that more attention should be paid to patients with borderline ABIs, especially with regard to cardiovascular death, stroke, and heart failure.

Ankle-brachial index and brachial-ankle pulse wave velocity are risk factors for ischemic stroke in patients with Type 2 diabetes

The incidence of ischemic stroke in patients with diabetes is increasing. While brachial-ankle pulse wave velocity (BaPWV) and ankle-brachial index (ABI) are known to be associated with ischemic cardiovascular and cerebrovascular diseases, whether these measures predict the risk of ischemic cerebrovascular disease in diabetic patients remains unclear. 117 patients with type 2 diabetes were enrolled in this study. According to the results of head magnetic resonance imaging, the patients were divided into a diabetes-only group (n = 55) and a diabetes and ischemic stroke group (n = 62). We then performed ABI and BaPWV examinations for all patients. Compared with the diabetes-only group, we found decreased ABI and increased BaPWV in the diabetes and ischemic stroke group. Multivariate logistic regression analyses revealed that BaPWV and ABI were risk factors for ischemic stroke in patients with type 2 diabetes. Our findings indicate that decreased ABI and increased BaPWV are objective indicators of increased risk of ischemic stroke in patients with type 2 diabetes.

Lower Extremity Peripheral Arterial Disease Is an Independent Predictor of Coronary Heart Disease and Stroke Risks in Patients with Type 2 Diabetes Mellitus in China

We aimed to determine the relationship between lower extremity peripheral arterial disease (PAD), 10-year coronary heart disease (CHD), and stroke risks in patients with type 2 diabetes (T2DM) using the UKPDS risk engine. We enrolled 1178 hospitalized T2DM patients. The patients were divided into a lower extremity PAD group (ankle-brachial index ≤ 0.9 or >1.4; 88 patients, 7.5%) and a non-PAD group (ankle-brachial index > 0.9 and ≤1.4; 1090 patients, 92.5%). Age; duration of diabetes; systolic blood pressure; the hypertension rate; the use of hypertension drugs, ACEI /ARB, statins; CHD risk; fatal CHD risk; stroke risk; and fatal stroke risk were significantly higher in the PAD group than in the non-PAD group (P < 0.05 for all). Logistic stepwise regression analysis indicated that ABI was an independent predictor of 10-year CHD and stroke risks in T2DM patients. Compared with those in the T2DM non-PAD group, the odds ratios (ORs) for CHD and stroke risk were 3.6 (95% confidence interval (CI), 2.2-6.0; P < 0.001) and 6.9 (95% CI, 4.0-11.8; P < 0.001) in those with lower extremity PAD, respectively. In conclusion, lower extremity PAD increased coronary heart disease and stroke risks in T2DM.

Borderline ankle-brachial index is associated with poor short-term clinical outcome after coronary artery intervention

OBJECTIVE

To evaluate the association between borderline ankle-brachial index (ABI) and clinical outcome in patients who underwent percutaneous coronary intervention (PCI).

METHODS

From August 2009 to August 2012, ABI was measured in 1291 patients who underwent PCI. Patients with borderline ABI were compared with those who had normal ABI. The primary outcome was major adverse cardiac and cerebrovascular event (MACCE), defined as a composite of all-cause death, myocardial infarction, stroke, and repeat revascularization.

RESULTS

Of the 1291 patients, 1154 (82%) had normal ABI and 89 (7%) had borderline ABI. The median overall follow-up duration was 19 (interquartile range 13-26) months. After adjustment with IPTW, the incidence of stroke (HR, 6.28; CI 95%, 1.95-20.19; P < 0.01) and MACCE (HR, 2.54; CI 95%, 1.40-4.62; P < 0.01) were higher in the borderline ABI group. In a propensity score-matched population, the incidence of stroke (HR, 4.68; CI 95%, 1.18-18.52; p = 0.03) and MACCE (HR, 2.12; CI 95%, 1.09-4.11; P = 0.03) were still significantly higher.

CONCLUSION

The presence of borderline ABI was associated with worse clinical outcome and increased stroke rate compared with normal ABI during the short-term follow-up period in patients who underwent coronary intervention.

Subclinical Atherosclerosis in Patients with Cushing Syndrome: Evaluation with Carotid Intima-Media Thickness and Ankle-Brachial Index

BACKGROUND

Cushing syndrome (CS) has been described as a killing disease due its cardiovascular complications. In fact, chronic cortisol excess leads to a constellation of complications, including hypertension, hyperglycemia, adiposity, and thromboembolism. The main vascular alteration associated with CS is atherosclerosis.

METHODS

Aim of this study was to analyze carotid intima-media thickness (cIMT) and ankle-brachial index (ABI), two surrogate markers of subclinical atherosclerosis in a consecutive series of CS patients, compared to patients with essential hypertension (EH) and health subjects (HS).

RESULTS

Patients with CS showed a significant increase (P<0.05) of cIMT (0.89±0.17 mm) compared to EH (0.81±0.16 mm) and HS (0.75±0.4 mm), with a high prevalence of plaque (23%; P<0.03). Moreover, CS patients showed a mean ABI values (1.07±0.02) significantly lower respect to HS (1.12±0.11; P<0.05), and a higher percentage (20%) of pathological values of ABI (≤0.9; P<0.03).

CONCLUSION

In conclusion, we confirmed and extended the data of cIMT in CS, and showed that the ABI represent another surrogate marker of subclinical atherosclerosis in this disease.

The efficacy and safety of cilostazol in ischemic stroke patients with peripheral arterial disease (SPAD): protocol of a randomized, double-blind, placebo-controlled multicenter trial

RATIONALE

It is not uncommon for patients with ischemic stroke to have peripheral arterial disease (PAD). Patients with polyvascular diseases carry greater burden of atherosclerosis and higher risks of developing vascular events and death. More effective regimens, such as dual antiplatelet agents, may be more effective for controlling progression of atherosclerosis in secondary prevention.

AIM

This study aims to evaluate whether cilostazol plus aspirin is more efficacious than aspirin alone for preventing progression of atherosclerosis in patients with ischemic stroke or transient ischemic attack (TIA) who also have peripheral arterial disease.

DESIGN

The Safety and Efficacy of Cilostazol in Ischemic Stroke Patients with Peripheral Arterial Disease (SPAD) study is a randomized double-blinded placebo-controlled trial. Patients with previous ischemic stroke or TIA who had been taking aspirin (100 mg per day), aged 50 years or older, with PAD in the lower limbs based on ankle-brachial index (ABI) <1·0 will be randomized into the treatment group with cilostazol (200 mg/day) or the placebo group on 1:1 basis.

STUDY OUTCOMES

Patients will be evaluated at 1, 3, 6, 9 and 12 months after randomization. The primary endpoint is difference in change in ABI between groups. The secondary and tertiary endpoints are the difference between groups in change in carotid intima-media thickness (IMT) and incidence rate of major cardiovascular events, including recurrent stroke, myocardial infarction, unstable angina, other vascular events, and death; and the safety measures, including major bleeding events, hemorrhagic stroke and death of any cause.

CONCLUSION

The SPAD trial is the first study to evaluate the safety and efficacy of dual antiplatelet agents, aspirin plus cilostazol, in comparison with aspirin alone in patients with both ischemic stroke or TIA and PAD. Results from this trial will provide important information on the merit of adding cilostazol to aspirin for slowing down progression of atherosclerosis in patients with ischemic stroke and PAD.

Borderline ankle-brachial index value of 0.91-0.99 is associated with endothelial dysfunction

BACKGROUND

An ankle-brachial index (ABI) value of 0.91-0.99 is considered borderline and associated with an increased risk of cardiovascular events. However, there is no information on the relationship between borderline ABI and endothelial function.

METHODS AND RESULTS

We measured ABI and assessed vascular function by flow-mediated vasodilation (FMD) and nitroglycerin-induced vasodilation in 389 subjects who underwent health examinations. Subjects were divided into 3 groups according to ABI (normal group: 1.00-1.40, borderline group: 0.91-0.99, abnormal group: ≤0.90 or >1.40). FMD was significantly smaller in both the borderline and the abnormal group than in the normal group. There was no significant difference in the vascular responses to nitroglycerin between the normal and borderline groups. Vascular response to nitroglycerin was significantly higher in the normal group than in the abnormal group. Borderline and abnormal ABI values were significantly associated with an increased odds ratio of low tertile of FMD levels, using the normal ABI group as the reference. Multiple logistic regression analysis for FMD revealed that age, sex, hypertension, diabetes mellitus, and borderline ABI independently remained associated with FMD.

CONCLUSIONS

ABI of 0.91-0.99 is associated with endothelial dysfunction. ABI examination is a simple and cost-effective method for obtaining the additional information on the initial step of atherosclerosis beyond the assessment of peripheral artery disease.

PREVALENCE OF MULTI-FOCAL ATHEROSCLEROTIC PATHOLOGY ACROSS AGE GROUPS

Aim. To compare the prevalence of multi-focal subclinical atherosclerotic pathology and its determinants in cardiovascular surgery patients.

Material and methods. The study included 1018 patients — 825 en and 193 women (mean age 59,0±12,0 years) — who were hospitalised for a planned intervention on coronary or other arteries. Group I (n=542) was aged under 60 years, Group II (n=215) — 60–64 years, Group III (n=141) — 65–69 years, and Group IV (n=120) — 70 years or older. All participants underwent coronary angiography and Doppler ultrasound; peripheral angiography was performed, if necessary. Multi-focal atherosclerosis (MFA) criteria were the presence of stenosis (≥30%) or revascularisation in two or more vascular territories.

Results. Subclinical atherosclerotic pathology of various localisation was observed in 52,3% of the patients. Advanced age was linked to an increase in the MFA prevalence: from 45,8% in Group I to 58,6% in Group II, 58,2% in Group III, and 63,3% in Group IV (p=0,0001). In Group I, MFA was associated with the intermittent claudication syndrome (ICS), decreased body mass index (BMI), increased intima-media thickness (IMT), elevated total cholesterol (TCH). However, in Groups II–IV, the only association observed was between MFA and ICS.

Conclusion. Taking into account the subclinical (hemodynamically insignificant) arterial pathology had resulted in a high prevalence of MFA. Advanced age was associated with a higher MFA prevalence. Other factors linked to MFA were increased IMT, elevated TCH, decreased BMI, and ICS. 

Ankle brachial pressure index as a marker of apathy in a community-dwelling population

BACKGROUND

Apathy is defined as a lack of interest or emotion. Several studies have shown the relationship between apathy and atherosclerotic change in poststroke patients. Although apathy is confused with depression, it might be a specific neuropsychiatric syndrome separate from depression.

OBJECTIVE

To clarify the relationship between atherosclerotic change and apathy in a community-dwelling population, which does not include the psychologic factors associated with stroke events.

METHODS

The ankle brachial pressure index (ABI) was measured using a volume-plethymographic apparatus in 860 volunteers (315 males and 545 females) who participated in the Iwaki Health Promotion Project 2008. Starkstein's apathy score and the Center for Epidemiologic Studies Depression Scale (CES-D) were used to assess the psychologic status. The association between the ABI and apathy was assessed by a multiple linear regression analysis.

RESULTS

Gender and low-density lipoprotein (LDL)-cholesterol were independently and significantly associated with the CES-D score. We did not find any association between CES-D score and the ABI. In addition, the extent of education and the ABI were independently and significantly associated with the apathy scale (AS).

CONCLUSION

In a community-dwelling population, a lower ABI score was an independent risk factor for a higher AS score, but not for a higher CES-D score. Apathy and depression may have different etiologies in vascular factors.

Ankle blood pressure and pulse pressure as predictors of cerebrovascular morbidity and mortality in a prospective follow-up study

Background and Objective. We examined the association of elevated ankle blood pressure (ABP), together with exercise blood pressure, with incident cerebrovascular (CV) morbidity and mortality in a prospective follow-up study of 3,808 patients. The results were compared with pulse pressure, another indicator of arterial stiffness. Methods. Patients with normal ankle and exercise brachial blood pressures were taken as the reference group. Pulse pressure was considered as quartiles with the lowest quartile as the reference category. Results. A total of 170 subjects had a CV event during the follow-up. Multivariate adjusted hazard ratio of a CV event was 2.24 (95% CI 1.43–3.52, P < .0001) in patients with abnormal ABP. The pulse pressure was significant only in the model adjusted for age and sex. Conclusion. The risk of a future CV event was elevated already in those patients among whom elevated ABP was the only abnormal finding. As a risk marker, ABP is superior to the pulse pressure.

Relationship between peripheral arterial disease and incident disability among elderly Japanese: the Tsurugaya project

AIM

The aim of this study was to investigate whether peripheral arterial disease (PAD) is predictive of disability and whether the relationship between PAD and disability can be fully explained by baseline physical functions.

METHODS

We followed for five years 783 Japanese aged 70 years or older without a disability at baseline in 2003. We defined participants certificed as requiring long-term care as having incident disability. The hazard ratio (HR) and 95% confidence interval (95% CI) for incident disability were calculated using the Cox proportional hazards model.

RESULTS

After adjusting for possible confounders other than physical function, the HR of incident disability among participants with PAD was 1.86 (95%CI: 1.06 to 3.26).Although the risk was attenuated (HR=1.63, 95%CI: 0.92 to 2.86) after adding baseline physical function as a covariate, the HR was still high. Furthermore, the relation was not statistically significant, but the group with higher physical function and PAD also had a higher HR of incident disability than those who had higher physical function without PAD.

CONCLUSION

PAD is an important predictor of disability even if the level of baseline physical function is high.

The Prevalence of Peripheral Arteriopathy is Higher in Ischaemic Stroke as Compared with Transient Ischaemic Attack and Intracerebral Haemorrhage

Background:

There is little data on the association of peripheral arterial disease and stroke. We aimed to assess the prevalence of peripheral arterial disease in acute stroke and to identify the predisposing factors for peripheral arterial disease in a stroke cohort.

Methods:

We enrolled all consecutive patients who were admitted to our stroke- and neurocritical care units with the diagnosis of a transient ischaemic attack, ischaemic or haemorrhagic stroke over a period of 5 months. As controls, we analysed 50 nonvascular neurological patients who were matched to age. Upon admission, assessment of the ankle brachial index was performed in all patients. The only exclusion criteria was decompensated congestive heart failure.

Results:

Altogether, we compared 374 stroke patients (95 transient ischaemic attack, 231 ischaemic, and 48 haemorrhagic strokes) and 50 nonstroke controls. The prevalence of peripheral arterial disease in the control group was 14%. There was a trend towards a higher prevalence of peripheral arterial disease in stroke patients (χ2-test: P = 0.051; prevalence peripheral arterial disease in transient ischaemic attack: 16.8%, ischaemic stroke: 32%, and haemorrhagic stroke: 20.8%). A higher proportion of ischaemic stroke patients were peripheral arterial disease-positive, compared with transient ischaemic attack patients ( P = 0.005) and controls ( P = 0.011), respectively. Multivariate regression analyses identified the parameters age, arterial hypertension, current or former smokers and a history of cardiovascular events to be predisposing factors of peripheral arterial disease.

Conclusion:

This study represents the first systematic investigation of the prevalence of peripheral arterial disease in stroke. By now, it is clear that: • peripheral arterial disease is more commonly found in stroke than in nonstroke patients • ischaemic stroke patients show the highest prevalence of peripheral arterial disease, and • peripheral arterial disease in stroke is related to common vascular risk factors.