Combination of the ankle-brachial index and percentage of mean arterial pressure to improve diagnostic sensitivity for peripheral artery disease: An observational study

Achilles tendon thickness normalized to body surface area as a marker of asymptomatic peripheral arterial disease

OBJECTIVES

The normalisation of Achilles tendon thickness (ATT) to anthropometric parameters may increase the diagnostic efficiency of the assessment of ATT. The aim of this study was to compare the diagnostic value of AT dimensions depending on their normalization to body surface area (BSA) in patients with asymptomatic peripheral arterial disease (PAD).

METHODS

All patients underwent duplex scanning of the carotid arteries and the lower limb arteries. Asymptomatic PAD was defined as the presence of ≥50% stenosis in the carotid and/or lower limb arteries. ATT was measured using a longitudinal scan, width (ATW) and cross-sectional area (AT CSA), which was determined during a cross-sectional scan.

RESULTS

The study included 369 patients, among whom asymptomatic PAD was detected in 18 (4.88%) patients. Only the ATT demonstrated diagnostic value for asymptomatic PAD. After normalizing the size of the AT to the BSA, the diagnostic performance of ATT, ATW and AT CSA became statistically significant. Among the studied parameters, only an increase in ATT/BSA >0.29 cm/m2 was associated with a significant increase in the odds ratio (OR) of asymptomatic PAD by 4.11 times (95% CI 1.08-15.7; p = .038) after adjustments.

CONCLUSION

An increase in ATT/BSA >0.29 cm/m2 predicted the presence of asymptomatic PAD with a sensitivity of 61.1% and a specificity of 77.9%. ATT/BSA values of less than 0.29 cm/m2 made it possible to exclude asymptomatic PAD with a probability of 97.5%. An increase in ATT/BSA >0.29 cm/m2 was associated with a 4.11-fold increase in the OR of asymptomatic PAD (95% CI 1.08-15.7).

Identifying peripheral arterial disease in the elderly patients using machine-learning algorithms

BACKGROUND

Peripheral artery disease (PAD) is a common syndrome in elderly people. Recently, artificial intelligence (AI) algorithms, in particular machine-learning algorithms, have been increasingly used in disease diagnosis.

AIM

In this study, we designed an effective diagnostic model of PAD in the elderly patients using artificial intelligence.

METHODS

The study was performed with 539 participants, all over 80 years in age, who underwent the measurements of Doppler ultrasonography and ankle-brachial pressure index (ABI). Blood samples were collected. ABI and two machine-learning algorithms (MLAs)-logistic regression and a random forest (RF) model-were established to diagnose PAD. The sensitivity and specificity of the models were analyzed. An additional RF model was designed based on the most significant features of the original RF model and a prospective study was conducted to demonstrate its external validity.

RESULTS

Thirteen of the 28 features introduced to the MLAs differed significantly between PAD and non-PAD participants. The respective sensitivities and specificities of logistic regression, RF, and ABI were as follows: logistic regression (81.5%, 83.8%), RF (89.3%, 91.6%) and ABI (85.1%, 84.5%). In the prospective study, the newly designed RF model based on the most significant seven features exhibited an acceptable performance rate for the diagnosis of PAD with 100.0% sensitivity and 90.3% specificity.

CONCLUSIONS

An RF model was a more effective method than the logistic regression and ABI for the diagnosis of PAD in an elderly cohort.

The early diagnostic value of ankle-brachial index combined with feet electrochemical skin conductance for peripheral artery disease in type 2 diabetes

Aims/Introduction

In this paper, we focused on exploring the diagnostic and predictive clinical utility of ankle‐brachial index (ABI) in combination with feet electrochemical skin conductance (FESC) for peripheral artery disease (PAD) in Chinese patients with type 2 diabetes mellitus (T2DM).

Materials and Methods

Overall, 183 Chinese T2DM patients were enrolled in this study. The patients were classified into three groups: Group 1 comprised of uncomplicated type 2 diabetics (n = 36), Group 2 consisted of patients with diabetic peripheral neuropathy (n = 103) whereas Group 3 patients displayed peripheral artery disease (n = 44). All patients underwent Sudoscan test using a Sudoscan (Paris, France) and ABI assessment.

Results

Multivariate logistic regression models revealed that FESC was an independent risk factor of developing PAD in patients with type 2 diabetes. The AUC for diagnostic, positive predictive and negative predictive value of ABI in combination with FESC for PAD were 0.907, 0.733 and 0.920, respectively. The specificity and sensitivity of ABI in combination with FESC for PAD were 0.914 and 0.750, respectively.

Conclusions

Ankle‐brachial index in combination with FESC can accurately be used in early diagnosis of PAD.

Variability in Annual Fasting Glucose and the Risk of Peripheral Artery Disease in Patients with Diabetes Mellitus

PURPOSE

High glucose concentrations and swings are associated with endothelial dysfunction. We examined the effects of variability in fasting plasma glucose on peripheral artery disease (PAD) in patients with diabetes mellitus (DM).

PATIENTS AND METHODS

In this screening study for the risk factors of PAD, we retrospectively collected data on the ankle-brachial index (ABI) and the percentage of mean arterial pressure (%MAP) at the ankle between August 01, 2016 and July 31, 2017. We defined low ABI ≤0.90, high %MAP ≥45%, or both as high-risk PAD and others as low-risk PAD. We compared the standard deviation (SD) of the first fasting plasma glucose data available each year after January 01, 2007.

RESULTS

In 2577 patients, a higher SD of annual fasting glucose was observed in those with an ABI ≤0.90 than in patients with an ABI >0.90 (2.6 ± 2.1 vs 2.2 ± 2.3, P = 0.009), and in patients with %MAP ≥45% than in those with %MAP <45% (2.4 ± 2.1 vs 2.2 ± 2.3, P = 0.034). A high-risk PAD was significantly associated with the SD (P = 0.032) but not with the mean (P = 0.338) of annual fasting glucose. The former was an independent risk factor for high-risk PAD (odds ratio = 1.424; 95% CI = 1.118‒1.814; P = 0.004).

CONCLUSION

Variability but not mean of annual fasting plasma glucose was significantly associated with a high risk of PAD in patients with DM.

Upstroke Time Is a Useful Vascular Marker for Detecting Patients With Coronary Artery Disease Among Subjects With Normal Ankle-Brachial Index

Background Upstroke time is the transit time from the nadir to peak of the waveform of pulse volume recording. The purpose of this study was to determine whether upstroke time at the ankle is a useful vascular marker for detecting patients with advanced atherosclerosis in combination with ankle-brachial index (ABI). Methods and Results We measured upstroke time and ABI in 2313 subjects (mean age, 61.2±15.3 years). The prevalence of coronary artery disease (CAD) was significantly higher in patients with prolonged upstroke time (≥180 ms) than in subjects with normal upstroke time (<180 ms) (29.6% versus 11.8%; P<0.001), with a significant association between prolonged upstroke time and an increased risk of CAD (odds ratio [OR], 1.61; 95% CI, 1.07-2.44; P=0.02). In 1954 subjects with normal ABI (1.00 ≤ ABI ≤ 1.40), the prevalence of CAD was significantly higher in patients with prolonged upstroke time than in subjects with normal upstroke time (29.5% versus 10.6%; P<0.001), with a significant association between prolonged upstroke time and CAD (OR, 2.33; 95% CI, 1.41-3.87; P=0.001), whereas there was no significant association between upstroke time and CAD in subjects with low ABI (<1.00) (OR, 1.24; 95% CI, 0.72-2.16; P=0.44). Conclusions Upstroke time may be a useful vascular marker for detecting patients with CAD, especially in subjects with normal ABI who are usually considered not to have advanced atherosclerosis by ABI measurement alone. More attention should be paid to upstroke time for detecting patients with advanced atherosclerosis. Registration URL: https://www.umin.ac.jp; Unique identifier: UMIN000039512.

Correlations Between the Ankle-Brachial Index, Percentage of Mean Arterial Pressure, and Upstroke Time for Endovascular Treatment

Background

The ankle-brachial index (ABI), percentage of mean arterial pressure (%MAP), and upstroke time (UT) are indicators to diagnose lower-extremity peripheral artery disease (PAD). However, the respective relationship between these parameters is unknown. In this study, we analyzed the correlations between ABI, %MAP, and UT and examined their clinical usefulness for endovascular treatment (EVT).

Methods

Sixty-three consecutive subjects who underwent successful EVT for aortoiliac to femoropopliteal artery diseases were analyzed. The ABI, %MAP, and UT were measured using an automated oscillometric device.

Results

There were significant correlations between the ABI and %MAP (r = -0.425, P < 0.001), the ABI and UT (r = -0.304, P = 0.017), and %MAP and UT (r = 0.368, P = 0.003). In terms of lesion length, there was a significant difference in %MAP after EVT (focal, 42.6%; short, 44.5%; intermediate, 47.1%; long, 49.1%; P = 0.015). There was minimal %MAP improvement in the case of a long lesion length (focal, -8.83%; short, -5.10%; intermediate, -3.00%; long, -1.50%; P = 0.006). Excessive lesion calcification also hindered %MAP improvement (grade 0, -7.16%; grade 1, -5.52%; grade 2, -4.71%; grade 3, -2.80%; grade 4, -1.00%; P = 0.049). Patients who underwent re-EVT (an average of 10.1 months after initial EVT) had minimal %MAP improvement (-2.76% vs. -5.95%, P = 0.035) at the first outpatient visit (an average of 3.3 weeks after EVT).

Conclusions

In conclusion, the ABI, %MAP, and UT are correlated with each other. If the length of the lesion is long and there is excessive calcification, %MAP improvement is minimal. Moreover, minimal %MAP improvement may be an indicator of future restenosis.

Use of the ankle-brachial index combined with the percentage of mean arterial pressure at the ankle to improve prediction of all-cause mortality in type 2 diabetes mellitus: an observational study

Background

Peripheral artery disease (PAD) in the lower extremities is a common complication of type 2 diabetes and has been shown to be associated with mortality. The ankle-brachial index (ABI) is a simple noninvasive method to screen PAD, but this method has limited sensitivity. We hypothesized that using the percentage of mean arterial pressure (%MAP) in combination with the ABI would improve the prediction of mortality.

Methods

We retrospectively collected data from patients with type 2 diabetes who had undergone ABI and  %MAP measurements at our hospital. We separated the cohort into four groups according to their ABI and  %MAP values, and we examined whether these indices were associated with mortality.

Results

A total of 5569 patients (mean age, 65 ± 11 years) were enrolled. During the follow-up period (median, 22.9 months), 266 (4.8%) of the enrolled patients died. The combination of ABI and  %MAP was significantly more effective than ABI alone for predicting mortality (C index of 0.62, 95% confidence interval [CI] of 0.57 to 0.65 vs. C index of 0.57, 95% CI of 0.53 to 0.62; P = 0.038). In multivariate analysis (with a reference group defined by ABI > 0.90 and  %MAP ≤ 45%), the highest risk of mortality was seen in patients with ABI ≤ 0.90 and  %MAP > 45% (hazard ratio = 2.045 [95% CI 1.420, 2.945], P < 0.001).

Conclusions

The use of  %MAP alongside ABI appears to significantly improve the prediction of all-cause mortality in patients with type 2 diabetes.

Mean and variability of annual haemoglobin A1c are associated with high-risk peripheral artery disease

BACKGROUND

Glucose variability is predictive of cardiovascular events and all-cause mortality. However, the association between peripheral artery disease and glucose variability has not been thoroughly investigated. Therefore, the standard deviation of annual haemoglobin A1c was assessed in patients with type 2 diabetes for evaluating the different risks of peripheral artery disease.

METHODS

A total of 4144 patients underwent an evaluation for the ankle-brachial index and the percentage of mean arterial pressure at the ankle. The first haemoglobin A1c record was retrospectively collected from each year until the ankle-brachial index measurement.

RESULTS

The standard deviation of annual haemoglobin A1c was higher in patients with ankle-brachial index ⩽0.90 than in those with ankle-brachial index >0.90 (1.1 ± 0.9% vs 1.0 ± 0.8%, p = 0.009) and was higher in patients with percentage of mean arterial pressure ⩾45% than in those with percentage of mean arterial pressure <45% (1.1 ± 0.8% vs 1.0 ± 0.8%, p = 0.007). A high standard deviation and mean of annual haemoglobin A1c are associated with high-risk peripheral artery disease, which is defined as a combination of ankle-brachial index ⩽0.90, percentage of mean arterial pressure ⩾45% or both (odds ratio = 1.306; 95% confidence interval = 1.057-1.615; p = 0.014).

CONCLUSION

Fluctuation in the haemoglobin A1c value indicates higher risk for peripheral artery disease in patients with type 2 diabetes and poor glucose control.