High Ankle-Brachial Index Indicates Cardiovascular and Peripheral Arterial Disease in Patients With Type 2 Diabetes

Epidemiology and Burden of Peripheral Artery Disease in People With Type 2 Diabetes: A Systematic Literature Review

Type 2 diabetes (T2D) and lower-extremity peripheral artery disease (PAD) are growing global health problems associated with considerable cardiovascular (CV) and limb-related morbidity and mortality, poor quality of life and high healthcare resource use and costs. Diabetes is a well-known risk factor for PAD, and the occurrence of PAD in people with T2D further increases the risk of long-term complications. As the available evidence is primarily focused on the overall PAD population, we undertook a systematic review to describe the burden of comorbid PAD in people with T2D. The MEDLINE, Embase and Cochrane Library databases were searched for studies including people with T2D and comorbid PAD published from 2012 to November 2021, with no restriction on PAD definition, study design or country. Hand searching of conference proceedings, reference lists of included publications and relevant identified reviews and global burden of disease reports complemented the searches. We identified 86 eligible studies, mostly observational and conducted in Asia and Europe, presenting data on the epidemiology (n = 62) and on the clinical (n = 29), humanistic (n = 12) and economic burden (n = 12) of PAD in people with T2D. The most common definition of PAD relied on ankle-brachial index values ≤ 0.9 (alone or with other parameters). Incidence and prevalence varied substantially across studies; nonetheless, four large multinational randomised controlled trials found that 12.5%-22% of people with T2D had comorbid PAD. The presence of PAD in people with T2D was a major cause of lower-limb and CV complications and of all-cause and CV mortality. Overall, PAD was associated with poor quality of life, and with substantial healthcare resource use and costs. To our knowledge, this systematic review provides the most comprehensive overview of the evidence on the burden of PAD in people with T2D to date. In this population, there is an urgent unmet need for disease-modifying agents to improve outcomes.

Screening for Subclinical Atherosclerosis and the Prediction of Cardiovascular Events in People with Type 1 Diabetes

People with type 1 diabetes (T1D) have a high cardiovascular disease (CVD) risk, which remains the leading cause of death in this population. Despite the improved control of several classic risk factors, particularly better glycaemic control, cardiovascular morbidity and mortality continue to be significantly higher than in the general population. In routine clinical practice, estimating cardiovascular risk (CVR) in people with T1D using scales or equations is often imprecise because much of the evidence comes from pooled samples of people with type 2 diabetes (T2D) and T1D or from extrapolations of studies performed on people with T2D. Given that T1D onsets at a young age, prolonged exposure to the disease and its consequences (e.g., hyperglycaemia, changes in lipid metabolism or inflammation) have a detrimental impact on cardiovascular health. Therefore, it is critical to have tools that allow for the early identification of those individuals with a higher CVR and thus be able to make the most appropriate management decisions in each case. In this sense, atherosclerosis is the prelude to most cardiovascular events. People with diabetes present pathophysiological alterations that facilitate atherosclerosis development and that may imply a greater vulnerability of atheromatous plaques. Screening for subclinical atherosclerosis using various techniques, mainly imaging, has proven valuable in predicting cardiovascular events. Its use enables the reclassification of CVR and, therefore, an individualised adjustment of therapeutic management. However, the available evidence in people with T1D is scarce. This narrative review provides and updated overview of the main non-invasive tests for detecting atherosclerosis plaques and their association with CVD in people with T1D.

Ankle brachial index and its correlation with cardiovascular risk factors in pre-diabetes: Two-year cross-sectional study

Background

A state of impaired glucose tolerance is called prediabetes. The diagnosis of prediabetes is controversial, yet it still puts a person at risk for developing diabetes. The ankle-brachial index (ABI) is useful for identifying persons at risk for peripheral artery disease and for diagnosing the condition in those who have symptoms in their lower extremities and subclinical atherosclerosis. This study highlights ABI and its correlation with cardiovascular risk factors like lipid profile and anthropometric measurement including neck circumference in prediabetes so that primary care physicians may be able to diagnose early before advancing to diabetes.

Materials and Methods

This cross-sectional study of 2 years duration from December 2020 to September 2022 was conducted in the Department of Medicine, at a tertiary care teaching hospital situated in a rural area. Patients with pre-diabetes were enrolled and Ankle Brachial Index was calculated. The correlation of ABI with anthropometric measures and lipid profile was assessed.

Results

On calculating ABI by manual method 21% which is 42 out of 200 had low ABI (<0.9). On the other hand, on calculating ABI by probe method low range of ABI was found to be 37% which is 74 patients out of 200. There was a significant correlation between ABI and body mass index and lipid profile. The diagnostic performance of ABI < 0.9 had 56.8% sensitivity and 100.0% specificity.

Conclusion

ABI can be used as a noninvasive and cost-effective modality for assessing subclinical atherosclerosis in patients with prediabetes and thus prevent its morbid complications even assessed at the primary care physician level.

Reliability of bedside tests for diagnosing peripheral arterial disease in patients prone to medial arterial calcification: A systematic review

BACKGROUND

Medial arterial calcification (MAC), frequently associated with diabetes mellitus (DM) and chronic kidney disease (CKD), is a systemic vascular disorder leading to stiffness and incompressible arteries. These changes impede the accuracy of bedside tests to diagnose peripheral arterial disease (PAD). This review aimed to evaluate the reliability of bedside tests for the detection of PAD in patients prone to MAC.

METHODS

A systematic search (Pubmed, Embase, Web of Science, Cochrane, and Emcare) was performed according to the PRISMA guidelines to identify relevant studies providing data on the performance of bedside tests for the detection of PAD in patients prone to MAC. Studies were included when bedside test were compared to a reference standard. Primary endpoints were the positive and negative likelihood ratios (PLR, NLR). Methodological quality and risk of bias were evaluated using the QUADAS-2 tool.

FINDINGS

In total, 23 studies were included in this review. The most commonly evaluated test was the ankle-brachial index (ABI), followed by toe-brachial index (TBI), toe pressure (TP) measurements, and continuous wave Doppler (CWD). The majority of patients were older, male, and had DM. We found that ABI <0·9 was helpful to diagnose PAD, but failed to rule out PAD (NLR >0·2). The same applied for TP (NLR >0·3) and TBI (5 out of 6 studies revealed an NLR >0·2). CWD (loss of triphasic pattern) is reliable to exclude PAD (NLR 0-0·09), but was only validated in two studies. Overall, methodological quality was poor which led to risk of bias in 20 studies.

INTERPRETATION

The diagnosis of PAD in patients prone to MAC remains challenging. The ABI performed reasonably in the diagnosis of PAD, while the CWD (loss of triphasic signal) can be used to rule out PAD. This systematic review showed that test performances were generally poor with serious concerns in methodological quality of the included studies. We therefore counsel against the use of a single bedside test.

FUNDING

None to declare.

How to manage patients with polyvascular atherosclerotic disease. Position paper of the International Union of Angiology

Atherosclerosis is a systemic disease affecting multiple arterial territories. Patients with clinical atherosclerotic disease in one vascular bed are likely to have asymptomatic or symptomatic atherosclerotic lesions in other vascular beds. Specifically, peripheral arterial disease (PAD) often coexists with coronary and carotid disease. With progression of atherosclerotic disease in one vascular bed, the risk of clinical manifestations in other territories increases and the incidence of adverse cardiovascular events increases substantially with the number of affected vascular beds. Classical risk factors are associated with the development of polyvascular atherosclerotic disease (PVD) in different territories; however, to a different extent. Risk modification represents basic treatment of patients with PVD. All modifiable risk factors should be aggressively controlled by lifestyle modification and medication. Particular attention should be directed to patients with PAD who are often undertreated in spite of the proven benefits of guideline-based approach. There is currently no proof that identification of asymptomatic atherosclerosis and PVD improves clinical outcomes in patients who are already in prevention programs. Revascularization should be performed only in symptomatic vascular beds, using the least aggressive method according to consensual decision of a multidisciplinary vascular team.

Prediction models for the risk of cardiovascular diseases in Chinese patients with type 2 diabetes mellitus: a systematic review

OBJECTIVES

Diabetes mellitus (DM) is a serious public health issue worldwide, and DM patients have higher risk of cardiovascular diseases (CVDs), which is the leading cause of DM-related deaths. China has the largest DM population, yet a robust model to predict CVDs in Chinese DM patients is still lacking. This systematic review is carried out to summarize existing models and identify potentially important predictors for CVDs in Chinese DM patients.

STUDY DESIGN

Systematic review.

METHODS

Medline and Embase were searched for data from April 1st, 2011 to May 31st, 2018. A study was eligible if it developed CVD (defined as total CVD or any major cardiovascular component) risk prediction models or explored potential predictors of CVD specifically for Chinese people with type 2 DM. Standardized forms were utilized to extract information, appraise applicability, risk of bias, and availabilities.

RESULTS

Five models and 29 studies focusing on potential predictors were identified. Models for a primary care setting, or to predict total CVD, are rare. A number of common predictors (e.g. age, sex, diabetes duration, smoking status, glycated hemoglobin (HbA1c), blood pressure, lipid profile, and treatment modalities) were observed in existing models, in which urine albumin:creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR) are highly recommended for the Chinese population. Variability of blood pressure (BP) and HbA1c should be included in prediction model development as novel factors. Meanwhile, interactions between age, sex, and risk factors should also be considered.

CONCLUSIONS

A 10-year prediction model for CVD risk in Chinese type 2 DM patients is lacking and urgently needed. There is insufficient evidence to support the inclusion of other novel predictors in CVDs risk prediction functions for routine clinical use.

Asia-Pacific Consensus Statement on the Management of Peripheral Artery Disease: A Report from the Asian Pacific Society of Atherosclerosis and Vascular Disease Asia-Pacific Peripheral Artery Disease Consensus Statement Project Committee

BACKGROUND

Peripheral artery disease (PAD) is the most underdiagnosed, underestimated and undertreated of the atherosclerotic vascular diseases despite its poor prognosis. There may be racial or contextual differences in the Asia-Pacific region as to epidemiology, availability of diagnostic and therapeutic modalities, and even patient treatment response. The Asian Pacific Society of Atherosclerosis and Vascular Diseases (APSAVD) thus coordinated the development of an Asia-Pacific Consensus Statement (APCS) on the Management of PAD.

OBJECTIVES

The APSAVD aimed to accomplish the following: 1) determine the applicability of the 2016 AHA/ACC guidelines on the Management of Patients with Lower Extremity Peripheral Artery Disease to the Asia-Pacific region; 2) review Asia-Pacific literature; and 3) increase the awareness of PAD.

METHODOLOGY

A Steering Committee was organized to oversee development of the APCS, appoint a Technical Working Group (TWG) and Consensus Panel (CP). The TWG appraised the relevance of the 2016 AHA/ACC PAD Guideline and proposed recommendations which were reviewed by the CP using a modified Delphi technique.

RESULTS

A total of 91 recommendations were generated covering history and physical examination, diagnosis, and treatment of PAD-3 new recommendations, 31 adaptations and 57 adopted statements. This Asia-Pacific Consensus Statement on the Management of PAD constitutes the first for the Asia-Pacific Region. It is intended for use by health practitioners involved in preventing, diagnosing and treating patients with PAD and ultimately the patients and their families themselves.

Hypertension and high ankle brachial index: the overlooked combination

OBJECTIVE

Assessment of asymptomatic organ damage in the management of hypertension includes low (<0.9) ankle brachial index (ABI) values. No recommendations are given for patients with high ABI (≥1.3), despite evidence of an association with increased risk. We aimed to study the association of high ABI with all-cause mortality and cardiovascular outcomes in a hypertensive population.

METHODS

In anonymized clinical records from the Catalan Primary Care (SIDIAP) database, we designed a large cohort of hypertensive patients aged 35-85 years at the start date. Participants were excluded if they had previous heart failure, coronary heart disease, stroke, diabetes mellitus, or chronic kidney disease. The study population was categorized according to ABI values. Cox proportional hazards models were used to assess all-cause mortality, heart failure, acute myocardial infarction, and stroke.

RESULTS

From 2006 through 2015, SIDIAP records included 44 657 hypertensive patients with an ABI measurement 9126 of whom met inclusion criteria. The median follow-up (first to third quartiles) was 6.0 years (4.7-7.6). High ABI (≥ 1.3) was associated with an increase in mortality risk, hazard ratio, and 95% confidence interval: 1.44 (1.10-1.88), similar to the group with ABI at least 0.9 and less than 1.1, hazard ratio 1.36 (1.12-1.65), and lower than all groups with ABI less than 0.9. High ABI values tended to associate with heart failure, hazard ratio 1.34 (0.95-1.91), but the relation of high ABI with acute myocardial infarction and stroke was nonsignificant, hazard ratios 1.30 (0.72-2.35) and 0.97 (0.65-1.42), respectively.

CONCLUSION

Patients with high ABI values and hypertension presented an increased all-cause mortality risk that could be considered when advising such patients.

Pain reduction and improved vascular health associated with daily consumption of an anti-inflammatory dietary supplement blend

Purpose: The objective for this clinical pilot study was to evaluate changes to chronic pain, vascular health, and inflammatory markers when consuming a dietary supplement blend (DSB, CytoQuel^®), containing curcumin, resveratrol, tocotrienols, N-Acetylcysteine, and epigallocatechin gallate.

Materials and methods: An open-label study design was used where 21 study participants were evaluated at baseline and at 2 and 8 weeks after consuming DSB. Participants were randomized to consume 3 capsules once daily versus 2 capsules twice daily. Pain and activities of daily living questionnaires were used to gather subjective data on pain levels and interference with daily living. Blood pressure was measured in both arms and ankles, and the ankle-brachial index (ABI) calculated. Blood samples were used to evaluate markers associated with inflammation and cardiovascular health.

Results: Highly significant reduction of chronic pain was seen after 8 weeks (p<0.01), both at rest and when physically active. Faster improvement was seen when consuming 3 capsules once daily, compared to 2 capsules twice daily. The pain reduction resulted in improved sleep quality (p<0.1), and improved social functioning (p<0.01), and less need for support from others (p<0.05), Normalization of mildly elevated ABI at study start was seen after 2 weeks. Plasma fibrinogen and von Willebrand Factor and serum matrix metalloproteinase-9 (MMP-9) showed reduction after 2 weeks (not significant), whereas a reduction in serum interleukin-1 receptor antagonist-a (IL-1ra) was statistically significant after 2 weeks (p<0.05). Correlation between pain reduction and changes to MMP-9 after 8 weeks was highly significant (P<0.01), whereas correlation between pain reduction and changes to IL-1ra reached significance at 2 weeks for the group consuming 3 caps once daily (p<0.04).

Conclusion: Consuming DSB helped manage pain, increased comfort during daily activities, and improved vascular function. This was associated with selective effects on specific blood biomarkers associated with inflammation and vascular health.

Quantitative evaluation of graded hindlimb ischemia based on pharmacokinetic modelling and hemodynamic analysis of indocyanine green

OBJECTIVE

Accurate evaluation of the degree of hindlimb ischemia is challenging but essential for the diagnosis and treatment of peripheral vascular insufficiency. The aim of the study is to apply a multiparametric method for the quantitative estimation of mouse models with different degrees of hindlimb ischemia based on a dynamic fluorescence imaging-based strategy.

APPROACH

An adjustable hydraulic occluder was placed around the thigh root of one hindlimb to induce six different degrees of hindlimb ischemia. Five parameters were extracted to quantitatively evaluate the degree of ischemia, including perfusion rate (PR) and perfusion vascular density (PVD) from a mathematical model of indocyanine green (ICG) pharmacokinetics, rising time (T _rise), blood flow index (BFI) and mean fluorescence intensity (MFI) from time-series analysis of ICG hemodynamics.

MAIN RESULTS

The results showed that the normalized PR and BFI decreased while the normalized T _rise increased progressively with the degree of ischemia. The normalized PVD and MFI first increased and then decreased with the degree of ischemia. High correlation was observed between the degree of ischemia and the arterial oxygen saturation which was measured by an oximeter.

SIGNIFICANCE

The results of this work demonstrated that PR, BFI and T _rise can be used for the quantitative and comprehensive evaluation of graded hindlimb ischemia.

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.

Color Doppler Ultrasound Imaging in the Assessment of Iliac Endofibrosis

Endofibrosis (EF) of the iliac arteries is a flow-limiting condition typically seen in highly trained endurance athletes. Thirty-seven athletes (74 limbs) were referred to our department with suspected EF. All patients had a pre- and postexercise color Doppler ultrasound (CDU) of the iliac arteries. Doppler waveform and peak systolic velocity (PSV) and end-diastolic velocity (EDV) were assessed pre- and postexercise. Endofibrosis was diagnosed with CDU in 24 athletes (29 limbs). Arterial wall and course abnormalities were detected at rest in 20 (67%) symptomatic limbs of athletes with and 4 (22%) symptomatic limbs of athletes without EF. Postexercise abnormal waveforms of the stenotic/damped type were seen in the iliac arteries in all 29 limbs of athletes diagnosed with EF. These waveform changes were accompanied by high PSV (>350 cm/s) and EDV (>150 cm/s), with (n = 10; 34%) or without (n = 19; 66%) the evidence of reduced arterial lumen caliber. Color Doppler ultrasound can be used to detect EF.

Advances in our understanding of the influence of gender on patient outcomes with peripheral arterial disease co-occurring with diabetes

Peripheral arterial disease is an important predictor of cardiovascular morbidity and mortality. Patients with peripheral arterial disease are at a higher risk of myocardial infarction and stroke. The well-known coronary artery disease risk factors such as diabetes, hypertension, smoking and dyslipidemia are also risk factors for peripheral arterial disease. Hyperglycemia is an important mediator in the pathogenesis of this disease in diabetics, more so in women. The morbidity and poor outcomes associated with peripheral arterial disease in women are emerging. Women are more likely to present at an older age are often asymptomatic and have poorer outcomes with revascularization. Women experience specific sex-related challenges in the various diagnostic methods which could lead to a delay in diagnosis. This is a group which needs close attention and aggressive risk factor modification.

Relationship of Vascular Factors on Electrophysiologic Severity of Diabetic Neuropathy

OBJECTIVE

To investigate the impact of vascular factors on the electrophysiologic severity of diabetic neuropathy (DPN).

METHODS

Total 530 patients with type 2 diabetes were enrolled retrospectively. We rated severity of DPN from 1 (normal) to 4 (severe) based on electrophysiologic findings. We collected the data concerning vascular factors (including brachial-ankle pulse wave velocity [PWV], ankle brachial index, ultrasound of carotid artery, lipid profile from the blood test, and microalbuminuria [MU] within 24 hours urine), and metabolic factors of diabetes (such as glycated hemoglobin [HbA1c]). We analyzed the differences among the four subgroups using χ(2) test and ANOVA, and ordinal logistic regression analysis was performed to investigate the relationship between significant variables and severity of DPN.

RESULTS

The severity of DPN was significantly associated with duration of diabetes, HbA1c, existence of diabetic retinopathy and nephropathy, PWV, presence of plaque, low density lipoprotein-cholesterol and MU (p<0.05). Among these variables, HbA1c and presence of plaque were more significantly related with severity of DPN in logistic regression analysis (p<0.001), and presence of plaque showed the highest odds ratio (OR=2.52).

CONCLUSION

Our results suggest that markers for vascular wall properties, such as PWV and presence of plaque, are significantly associated with the severity of DPN. The presence of plaque was more strongly associated with the severity of DPN than other variables.