Further clinical validation of the walking impairment questionnaire for classification of walking performance in patients with peripheral artery disease

Gujarati translation, validity and reliability of Walking Impairment Questionnaire in people with intermittent claudication due to peripheral artery disease

INTRODUCTION

The Walking Impairment Questionnaire (WIQ) is a common and easy-to-use assessment of walking incapacity in people with claudication due to peripheral artery disease (PAD). It has four subscales: pain severity, walking distance, walking speed, and ability to climb stairs. It has not been translated into Gujarati, which limits its use in Indian subjects.

AIM

This study aims to translate and assess the validity and reliability of a Gujarati version of WIQ.

MATERIALS AND METHODS

This study had three phases: 1. Forward and backward translation and Cultural adaptation of WIQ into the Gujarati language by two independent translators, 2. Face and content validation by six clinical reviewers and 10 participants with PAD and Type II diabetes, 3. Concurrent and construct validity, test-retest reliability, and internal consistency of Gujarati, the WIQ was assessed on 160 participants with PAD and Type II diabetes who had a mean Ankle Brachial Index (standard deviation) <0.40 (0.1). The concurrent and construct validity of the WIQ was analyzed by correlating the WIQ distance and speed score with 6-minute walk distance (6MWD) and speed and WIQ total score with the Medical Outcome Study Questionnaire Short Form 36 (SF-36) score using Pearson's correlation coefficient. Test-retest reliability was analyzed using an intraclass correlation coefficient (ICC) with a seven-day interval between two questionnaire applications. Internal consistency of the total WIQ score was determined using Cronbach's alpha.

RESULTS

Following translation, the Gujarati WIQ was considered acceptable and understandable by people with PAD. There was excellent correlation between the WIQ distance score and 6-minute walk test distance (r = 0.95, P < .05)) , the WIQ speed score and 6-minute walk test speed score (r = 0.89, P < .05)) and the Gujarati WIQ total score and total score of physical functioning domain of SF- 36 (r = 0.99, P < .05). There was excellent test-retest reliability over 7 days for total WIQ score (ICC = 0.94). The Cronbach's alpha for internal consistency of 0.97 for total WIQ score were excellent. This demonstrates the sufficient homogeneity of the total questionnaire.

CONCLUSION

The Gujarati version of the WIQ is reliable and valid and can be used to assess self-reported walking impairment in Gujarati-speaking people with PAD and Type II Diabetes.

Predictors of walking capacity in patients with peripheral arterial disease

BACKGROUND

Walking capacity is severely impaired in patients with peripheral arterial disease (PAD). Given the prognostic importance of walking capacity, the level of evidence on possible predictors of walking capacity in patients with PAD is insufficient.

AIMS

To investigate the predictors of walking capacity in patients with PAD.

METHODS

A total of 51 patients with PAD were included in this cross-sectional study. Walking capacity was determined with 6‑minute walk test (6MWT) and walking impairment questionnaire (WIQ). Functional mobility was assessed with repeated sit-to-stand test (RSS) and timed up and go test (TUG). Hand-held dynamometer was used to measurement lower extremity muscle strength. Balance was assessed with Biodex Balance System-limit of stability (BBS-LOS). Fatigue was evaluated with fatigue impact scale (FIS).

RESULTS

There was a strong correlation between 6MWT walking distance and WIQ, two methods of assessing walking capacity (r = 0.835 p < 0.001). The 6MWT was correlated with RSS, TUG, lower extremity muscle strength, BBS-LOS and FIS. The WIQ was correlated with RSS, TUG, BBS-LOS and FIS. The RSS and FIS were independent determinants of the 6MWT and WIQ, accounting for 68% and 57% of the variance, respectively.

CONCLUSION

This study demonstrated that functional mobility and fatigue were independent predictors of walking capacity in patients with PAD. Both subjective and objective measurement methods can be used for determining the level of walking capacity in the patients with PAD.

Efficacy of a personalised activity plan for BREAKing UP sitting time in patients with intermittent claudication (the BREAK UP study)

INTRODUCTION

The aim of this study was to investigate the concept of an 8-week personalised activity plan, using short periods of physical activity to break up sitting time in people with Intermittent Claudication (IC), to improve walking ability, and reduce time spent sitting.

METHODS

The study was designed as a single centre, single arm, before and after study and is registered with clinicaltrials.gov (NCT04572737). The co-primary outcomes are time spent sitting and walking ability measured via the walking impairment questionnaire. Normally distributed data was analysed using paired samples T-tests; non-normally distributed data was analysed using related-samples Wilcoxon signed rank tests.

RESULTS

There was a significant improvement in both co-primary outcomes: walking ability and time spent sitting, as well as the following secondary outcomes: total bouts and time spent in prolonged sitting, time spent standing and stepping, anxiety, depression, and activity levels reported on the vascular quality of life questionnaire.

CONCLUSION

An 8-week personalised activity plan to break up sitting time shows promise as a treatment for people with IC, improving walking ability and reducing time spent sitting. This study supports the use of large randomised controlled trials to further develop this treatment in people with IC.

Use of the Walking Impairment Questionnaire and Walking Estimated-Limitation Calculated by History questionnaire to detect maximal walking distance equal to or lower than 250 m in patients with lower extremity arterial disease

Objective

The objective was to assess the accuracy and optimal threshold of the Walking Impairment Questionnaire (WIQ) and the Walking Estimated-Limitation Calculated by History (WELCH) questionnaire in identifying patients with a maximal walking distance (MWD) below or equal to 250 m.

Methods

This retrospective study screened 388 consecutive patients with suspected symptomatic lower extremity arterial disease (LEAD). Collected data included the patient's history, resting ankle-brachial index, WIQ, and WELCH. MWD was assessed with a treadmill test at 2 mph (3.2 km/h) with a 10% grade. An optimized threshold for detection of MWD ≤ 250 m was determined for each questionnaire via receiver operating characteristic (ROC) curves. Subsequently, multivariate analysis was performed to build a new simple score to detect MWD ≤ 250 m.

Results

The study included 297 patients (63 ± 10 years old). With a threshold of ≤ 64%, the WIQ predicted MWD ≤ 250 m with an accuracy of 71.4% (66.2, 76.5%). With a threshold of ≤ 22, the WELCH predicted a treadmill walking distance of ≤ 250 m with an accuracy of 68.7% (63.4, 74.0%). A new score with only four "yes or no" questions had an accuracy of 71.4% (66.3, 76.6%). Items on this new score consisted of the level of difficulty of walking 1 block, declared maximum walking distance, usual walking speed, and maximum duration of slow walking.

Conclusion

A WIQ score ≤ 64% and a WELCH score ≤ 22 help to predict a walking distance of ≤ 250 m in a treadmill test at 2 mph (3.2 km/h) with a 10% grade. A 4-item score could be used for rapid evaluation of walking distance among patients with LEAD, but the validity of this 4-item score requires further confirmation studies.

Tibio-pedal arterial pressure assessment during endovascular intervention to improve quality-of-life in patients with intermittent claudication

Objective

The aim of this study is to compare the quality-of-life (QOL) outcomes and the tibio-pedal arterial pressure post-endovascular intervention.

Background

Physiological assessment of peripheral arterial lesions is infrequently performed during endovascular interventions.

Materials and methods

We retrospectively reviewed all 343 patients with intermittent claudication who underwent an endovascular intervention via tibio-pedal artery access from October 2018 to May 2021. The baseline and post-intervention tibio-pedal arterial pressures from the pedal sheaths were measured. QOL was assessed using a pre-validated Walking Impairment Questionnaire (WIQ) score before and at 30-day after intervention. We compared the baseline tibio-pedal arterial pressure, post-intervention tibio-pedal arterial pressure, delta pressure (post-intervention minus baseline), baseline WIQ scores, 30-day WIQ scores, and delta score (30-day minus baseline).

Results

All 343 patients had successful tibio-pedal accesses. The average tibio-pedal arterial pressure at baseline was 87.0 ± 1.8 mmHg vs. 135.5 ± 1.7 mmHg post-intervention (p &lt; 0.001). Average baseline and 30-day WIQ scores were summation (99.8 ± 3.3 vs. 115.0 ± 3.1, p &lt; 0.001), walking distance (35.7 ± 1.3 vs. 42.5 ± 1.3, p &lt; 0.001), walking speed (21.1 ± 0.9 vs. 23.6 ± 0.8, p = 0.036), stair climbing (4.7 ± 1.4 vs. 24.2 ± 1.4, p = 0.019), and symptoms (18.8 ± 0.2 vs. 20.1 ± 0.2, p &lt; 0.001), respectively. When comparing the increased post-intervention tibio-pedal arterial pressure &lt;60 mmHg vs. ≥60 mmHg, the average delta WIQ scores were all significantly improved with summation (10.0 ± 3.9 to 25.8 ± 5.5, p = 0.01), walking distance (4.1 ± 1.7 to 9.8 ± 2.5, p = 0.02), walking speed (1.5 ± 1.1 to 4.3 ± 1.5, p = 0.02), stair climbing (2.3 ± 1.8 to 9.4 ± 2.5, p = 0.02), and symptoms (1.0 ± 0.3 to 1.8 ± 0.4, p = 0.04), respectively.

Conclusion

Increasing the post-intervention tibio-pedal arterial pressure by 60 mmHg can enhance QOL as suggested by improvement of WIQ scores.

Measuring walking impairment in patients with intermittent claudication: psychometric properties of the Walking Estimated-Limitation Calculated by History (WELCH) questionnaire

Objectives

Patient-reported outcome measures can facilitate the assessment of walking impairment in peripheral artery disease patients with intermittent claudication in clinical trials and practice. The aim of this study was to test the psychometric properties of the German version of the 'Walking Estimated-Limitation Calculated by History' (WELCH) questionnaire.

Methods

The assessed properties included feasibility, test-retest reliability, construct validity (i.e., convergent, divergent and known-groups validity) and responsiveness using classic psychometric methods. Psychometric properties were tested as part of a randomized controlled home-based exercise trial for patients with symptomatic peripheral artery disease at Fontaine stage IIA/B.

Results

Analyses were conducted in subgroups of 1,696 patients at baseline and 1,233 patients at 12-month follow-up (i.e., post-intervention) who completed the WELCH along with a battery of other self-report measures. The WELCH did not exhibit relevant floor or ceiling effects (< 15% achieved lowest or highest possible scores), showed evidence for good test-retest reliability (ICC = .81, 95% CI [.71-.88]) and was found to be well suited for self-completion by patients (< 5% missing data per item). WELCH scores showed moderate to strong correlations with related measures of walking impairment at both time points (Walking Impairment Questionnaire: r = .56 - .74; VascuQoL-25 activity subscale: r = .61 - .66) and distinguished well among patients with poor and high quality of life when adjusting for confounders (t = 13.67, p < .001, d = .96). Adequate divergent validity was indicated by a weaker correlation between the WELCH and general anxiety at both time points (GAD-7: r =  - .14 to  - .22). The WELCH improved by 6.61 points (SD = 17.04, 95% CI [5.13-8.10], d = 0.39) in response to exercise treatment and was able to identify large clinically important improvements observed on the walking distance (AUC = .78, 95% CI [.71-.84]) and speed subscales (AUC = .77, 95% CI [.68-.86]) of the Walking Impairment Questionnaire.

Conclusions

The WELCH is considered a feasible, reliable and valid patient-reported outcome measure for the measurement of walking impairment in patients with peripheral artery disease. The WELCH showed evidence for responsiveness to changes in walking impairment, yet further studies are warranted to conclusively determine the WELCH's ability to detect intervention effects.

Risk Models and Scores in Patients with Peripheral Artery Disease and Chronic Limb-threatening Ischemia: A Comprehensive Review

Peripheral artery disease (PAD) affects more than 200 million patients worldwide and chronic limbthreatening ischemia (CLTI) is the most advanced stage of PAD with very high morbidity and mortality rates. Cardiovascular medicine is trending towards a more personalized approach where each individual patient will be managed according to specific risk factors, disease characteristics, expectations related to their disease and individualized assessment of potential outcomes. For this reason, a number of risk models and scores have been developed during the last few years. Our aim in this comprehensive review article is to provide an overview of selected risk models and scores for patients with PAD and CLTI. Given that some of the published scores were of low quality (minimal discriminatory ability), we included scores that were already externally validated or scores that had promising initial findings. Available scoring systems were grouped in the five following categories according to their utility: i) scores that can detect asymptomatic patients who should be screened for PAD, ii) scores for assessment of functional status and quality of life in patients with PAD, iii) scores assessing risk for amputation and other major adverse limb events among patients with CLTI, iv) scores for the optimal revascularization strategy in each patient and scores predicting successful procedural outcomes; v) scores predicting short or long-term cardiovascular and limb related outcomes after either revascularization or at least angiographic assessment. Limitations of available scoring systems include development and validation in specific populations, lack of external validation (for some of them) and also lack of synchrony with current era endovascular technology. However, with further optimization of current scores and the development of new scores, the field of PAD and CLI can be transitioned to a personalized medicine approach.

Avoiding revascularization strategy versus revascularization with drug-coated balloon for the treatment of superficial femoral artery occlusive disease

OBJECTIVE

The aim of this study was to compare the efficacy, safety and treatment costs of superficial femoral artery revascularization (SFA) with drug-coated balloon(DCB) versus avoiding revascularization strategy for the treatment of symptomatic SFA disease.

METHODS

This retrospective single-center study reviewed 96 patients (113 limbs) with severe stenosis and occlusive SFA disease. All patients underwent either DCB(Group 1: n ​= ​55 limbs) or nonrevascularization (Group 2: n ​= ​58 limbs) between March 2015 and June 2019. The improvement of Rutherford class, walking impairment questionnaire score(WIQ), target limb reintervention, perioperative major adverse events, the catheterization laboratory cost and length of hospital stay were compared. The limb salvage and survival rates were calculated using the Kaplan-Meier method. Univariate and multivariate logistic regression analysis were performed to assess the association between factors and the improvement of Rutherford category at 12 months.

RESULTS

The median follow-up time of Groups 1 and 2 was 17 and 33 months, respectively. At 12 months, the Rutherford category significantly decreased in both groups (P ​< ​0.001), with no significant difference (79.7% vs. 64.3%, P ​= ​0.074). Furthermore, multivariate analysis showed that the selected therapeutic method was not an influential factor for the improvement of Rutherford class at 12 months. The WIQ overall score as well as three subscales scores (distance, speed and stair-climbing), the survival rate, limb salvage rate and the length of stay between the two groups were comparable. The perioperative adverse events rate and catheterization laboratory cost in Group 2 was significantly lower compared to Group 1 [(34253.69 ​± ​28172.87) yuan vs. (56936.76 ​± ​41278.36) yuan, P ​= ​0.001].

CONCLUSIONS

This study suggests that avoiding superficial femoral artery revascularization strategy has favorable efficacy and safety outcomes compared to combining revascularization with DCB in selected patients.

Telephone health coaching with exercise monitoring using wearable activity trackers (TeGeCoach) for improving walking impairment in peripheral artery disease: study protocol for a randomised controlled trial and economic evaluation

INTRODUCTION

Peripheral artery disease (PAD) is the third most prevalent cardiovascular disease worldwide, with smoking and diabetes being the strongest risk factors. The most prominent symptom is leg pain while walking, known as intermittent claudication. To improve mobility, first-line treatment for intermittent claudication is supervised exercise programmes, but these remain largely unavailable and economically impractical, which has led to the development of structured home-based exercise programmes. This trial aims to determine the effectiveness and cost advantage of TeGeCoach, a 12-month long home-based exercise programme, compared with usual care of PAD. It is hypothesised that TeGeCoach improves walking impairment and lowers the need of health care resources that are spent on patients with PAD.

METHODS AND ANALYSIS

The investigators conduct a prospective, pragmatic randomised controlled clinical trial in a health insurance setting. 1760 patients diagnosed with PAD at Fontaine stage II are randomly assigned to either TeGeCoach or care-as-usual. TeGeCoach consists of telemonitored intermittent walking exercise with medical supervision by a physician and telephone health coaching. Participants allocated to the usual care group receive information leaflets and can access supervised exercise programmes, physical therapy and a variety of programmes for promoting a healthy lifestyle. The primary outcome is patient reported walking ability based on the Walking Impairment Questionnaire. Secondary outcome measures include quality of life, health literacy and health behaviour. Claims data are used to collect total health care costs, healthcare resource use and (severe) adverse events. Outcomes are measured at baseline, 12 and 24 months.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Medical Association Hamburg. Findings are disseminated through peer-reviewed journals, reports to the funding body, conference presentations and media press releases. Data from this trial are made available to the public and researchers upon reasonable request.NCT03496948 (www.clinicaltrials.gov), Pre-results.

Treatment Effect of Drug-Coated Balloons Is Durable to 3 Years in the Femoropopliteal Arteries: Long-Term Results of the IN.PACT SFA Randomized Trial

Supplemental Digital Content is available in the text.

Background—

Randomized controlled trials have reported favorable 1-year outcomes with drug-coated balloons (DCBs) for the treatment of symptomatic peripheral arterial disease when compared with standard percutaneous transluminal angioplasty (PTA). Evidence remains limited on the durability of the treatment effect with DCBs in the longer term.

Methods and Results—

IN.PACT SFA is a single-blind, randomized trial (Randomized Trial of IN.PACT Admiral Paclitaxel-Coated Percutaneous Transluminal Angioplasty [PTA] Balloon Catheter vs Standard PTA for the Treatment of Atherosclerotic Lesions in the Superficial Femoral Artery [SFA] and/or Proximal Popliteal Artery [PPA]) that enrolled 331 patients with symptomatic (Rutherford 2–4) femoropopliteal lesions up to 18 cm in length. Patients were randomized 2:1 to receive treatment with DCB or PTA. The 36-month assessments included primary patency, freedom from clinically driven target lesion revascularization, major adverse events, and functional outcomes. At 36 months, primary patency remained significantly higher among patients treated with DCB compared with PTA (69.5% versus 45.1%; log rank P<0.001). The rates of clinically driven target lesion revascularization were 15.2% and 31.1% (P=0.002) for the DCB and PTA groups, respectively. Functional outcomes were similarly improved between treatment groups even though subjects in the DCB group required significantly fewer reinterventions versus those in the PTA group (P<0.001 for target lesion revascularization, P=0.001 for target vessel revascularization). There were no device- or procedure-related deaths as adjudicated by an independent Clinical Events Committee.

Conclusions—

Three-year results demonstrate a durable and superior treatment effect among patients treated with DCB versus standard PTA, with significantly higher primary patency and lower clinically driven target lesion revascularization, resulting in similar functional improvements with reduced need for repeat interventions.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01175850 for IN.PACT SFA phase I in the European Union and NCT01566461 for IN.PACT SFA phase II in the United States.

A mixed methods study of perceived barriers to physical activity, geriatric syndromes, and physical activity levels among older adults with peripheral artery disease and diabetes

Previous studies suggest a myriad of factors prevent individuals from engaging in physical activity; however, less is known about barriers faced by individuals with multiple chronic conditions, such as peripheral artery disease (PAD) and type 2 diabetes, and how these barriers may impact engagement in physical activity. To date, there are no studies that integrate simultaneous assessment of perceived barriers to physical activity and engagement in physical activity in older adults with PAD and diabetes. This integration is key to understanding the implications of barriers to physical activity and to developing strategies to address those barriers. Therefore, this study investigated the unique physical activity experiences of older adults with PAD and diabetes. This study used a concurrent mixed methods design. Ten adults aged 65 years and older with PAD and diabetes completed semistructured interviews about experiences with physical activity, self-reported questionnaires assessing quality of life and fear of falling, and measures of physical function (eg, 6-minute walk test, chair stand, gait speed). Physical activity was measured objectively with accelerometry. Inductive content analysis was used to identify themes, and integrated analysis was performed to evaluate patterns among qualitative and quantitative variables. On average, participants were 74 years old and spent 10% of their time in moderate or vigorous physical activity (range: 3%-18%); 80% of participants were men. Barriers to physical activity identified through qualitative interviews included lack of accessibility, lack of enjoyment of activity, lack of motivation, and pain and physical health. Facilitators to physical activity were social support, accessibility and convenience, and enjoyment of the activity. Participants with more sedentary time and less moderate or vigorous physical activity tended to report greater fear of falling and greater barriers to physical activity and achieved lower distances in 6-minute walk tests. This research provides insight into both the nature of perceived barriers to physical activity and engagement in physical activity among older adults with PAD and diabetes. The integration of self-reported measures and objective measures facilitates our understanding of the lived experiences of individuals with these conditions. Study findings can be used to support further investigation into factors that influence engagement in physical activity in individuals with PAD and diabetes and to assist in the development of strategies to address identified barriers.

Low Walking Impairment Questionnaire score after a recent myocardial infarction identifies patients with polyvascular disease

Objectives

To evaluate whether the Walking Impairment Questionnaire score could identify patients with polyvascular disease in a population with recent myocardial infarction and their association with cardiovascular events during two-year follow-up.

Design

A prospective observational study.

Setting

Patients admitted to the acute coronary care unit, the Department of Cardiology, Uppsala University Hospital.

Participants

Patients admitted with acute Non-STEMI- or STEMI-elevation myocardial infarction.

Main outcome measures

The Walking Impairment Questionnaire, developed as a self-administered instrument to assess walking distance, speed, and stair climbing in patients with peripheral artery disease, predicts future cardiovascular events and mortality. Two hundred and sixty-three patients with recent myocardial infarction answered Walking Impairment Questionnaire. Polyvascular disease was defined as abnormal findings in the coronary- and carotid arteries and an abnormal ankle–brachial index. The calculated score for each of all three categories were divided into quartiles with the lowest score in first quartile.

Results

The lowest (worst) quartile in all three Walking Impairment Questionnaire categories was associated with polyvascular disease, fully adjusted; distance, odds ratio (OR) 5.4 (95% confidence interval (CI) 1.8–16.1); speed, OR 7.4 (95% CI 1.5–36.5); stair climbing, OR 8.4 (95% CI 1.0–73.6). In stair climbing score, patients with the lowest (worst) score had a higher risk for the composite cardiovascular endpoint compared to the highest (best) score; hazard ratio 5.3 (95% CI 1.5–19.0). The adherence to medical treatment was high (between 81.7% and 99.2%).

Conclusions

The Walking Impairment Questionnaire is a simple tool to identify myocardial infarction patients with more widespread atherosclerotic disease and although well treated medically, stair climbing predicts cardiovascular events.

Experience Implementing Supervised Exercise Therapy for Peripheral Artery Disease

Background

Supervised exercise therapy (SET) is a cornerstone of treatment for improving walking distance for individuals with symptomatic peripheral artery disease and claudication. High quality randomized controlled trials have documented the efficacy of SET as a claudication treatment and led to the recent Centers for Medicare and Medicaid decision to cover supervised exercise therapy (SET). However, to date, the translation of highly controlled, laboratory based SET programs in real world cardiopulmonary rehabilitation settings has been unexplored.

Methods

In this article, we describe our experience integrating SET into existing cardiopulmonary rehabilitation programs, focusing on patient evaluation, exercise prescription, outcome assessments, strategies to maximize program adherence, and transitioning to home and community-based exercise training.

Results

Our team has over 3 years experience successfully implementing SET in cardiac rehabilitation settings. The experiences communicated within can serve as a model for rehabilitation therapists to follow as they begin to incorporate SET in their rehabilitation programs.

Conclusions

CMS reimbursement has the potential to change clinical practice and utilization of SET for patients with symptomatic peripheral artery disease. The experience we have gained through implementation of SET programs across the M Health and Fairview Health Systems and in other Minnesota communities, including specific elements in our programs and the lessons learned from our clinical experience, can inform and help to guide development of new programs.

Brief Abstract

The recent Centers for Medicare and Medicaid decision to cover supervised exercise therapy (SET) for beneficiaries with peripheral artery disease (PAD) has the potential to transform practice. In this article, we describe our experience integrating SET into existing cardiopulmonary rehabilitation programs, which could serve as a model for new programs.

Gait pattern in patients with peripheral artery disease

Background

The aim of the present paper is to assess the gait pattern of patients with Peripheral Artery Disease (PAD). A more specific aim is to compare the gait pattern of PAD patients before and after the appearance of intermittent claudication symptoms.

Methods

The study involved 34 PAD patients with a claudication distance ≥200 m and 20 participants without PAD, who formed the control group. The gait pattern of PAD patients was assessed twice: before the appearance of intermittent claudication symptoms (pain-free conditions) and after the appearance of intermittent claudication symptoms (pain conditions).

Results

Compared to the control group, PAD patients presented a statistically significant decrease in step length both during pain-free conditions (52.6 ± 12.5 vs. 72.8 ± 18.5 cm, p = 0.008) and in pain conditions (53.3 ± 13.3 vs. 72.8 ± 18.5 cm, p = 0.006). As for the remaining spatiotemporal parameters, there were no differences observed between the patient group and the controls. Intermittent claudication symptom induced by the walking test on the treadmill did not bring about any new abnormalities in the gait pattern or intensify the existing abnormalities of the gait.

Conclusions

PAD patients have a tendency to shorten their step length regardless of the presence of intermittent claudication.

Translation of an evidence-based therapeutic exercise program for patients with peripheral artery disease

The purpose of this study was to implement and evaluate quality outcomes including referral, enrollment, and completion rates of a new peripheral artery disease (PAD)-specific supervised exercise therapy (SET) program within a preexisting clinical exercise wellness program and to evaluate the clinical effectiveness and patient-centered outcomes derived from 12 weeks of PAD-specific SET. Recruited participants completed an individualized, minimally supervised, PAD-specific SET program based on the AHA-ACC guidelines. Exercise workloads (metabolic equivalents of task [METs]) were tracked and evaluated throughout the program. Short Physical Performance Battery, 6-minute walk test (6MWT) Walking Impairment Questionnaire, Short-Form 36 (SF-36), and Peripheral Artery Disease Quality of Life Questionnaire (PADQOL) were assessed before and after the program. Paired t-tests were used to examine differences between baseline and follow-up outcome variables. On average, participants (n = 46) attended 23 (standard deviation [SD] 12.9) out of the possible 36 training sessions, for a 64% attendance rate. Among participants who used treadmill walking as the primary mode of exercise (n = 40), the overall mean MET level just prior to program completion was 3.79 (SD 1.49), which represented an increase of 0.92 (34%) METs compared to baseline (P < .001). Total distance on the 6MWT increased 115 (11%) feet (P = .011), which is considered a clinically meaningful improvement. Significant improvements were noted in the PADQOL: symptoms and limitations in physical functioning (P = .007). This study demonstrates that a minimally staffed PAD-specific SET program can improve functional performance in patients with claudication due to PAD and serves as a foundation to help build a clinically effective, Centers for Medicare and Medicaid reimbursed PAD-specific rehabilitation program.

Blood pressure and calf muscle oxygen extraction during plantar flexion exercise in peripheral artery disease

Peripheral artery disease (PAD) is an atherosclerotic vascular disease that affects 200 million people worldwide. Although PAD primarily affects large arteries, it is also associated with microvascular dysfunction, an exaggerated blood pressure (BP) response to exercise, and high cardiovascular mortality. We hypothesized that fatiguing plantar flexion exercise that evokes claudication elicits a greater reduction in skeletal muscle oxygenation (SmO₂) and a higher rise in BP in PAD compared with age-matched healthy subjects, but low-intensity steady-state plantar flexion elicits similar responses between groups. In the first experiment, eight patients with PAD and eight healthy controls performed fatiguing plantar flexion exercise (from 0.5 to 7 kg for up to 14 min). In the second experiment, seven patients with PAD and seven healthy controls performed low-intensity plantar flexion exercise (2.0 kg for 14 min). BP, heart rate (HR), and SmO₂ were measured continuously using near-infrared spectroscopy (NIRS). SmO₂ is the ratio of oxygenated hemoglobin to total hemoglobin, expressed as a percent. At fatigue, patients with PAD had a greater increase in mean arterial BP (18 ± 2 vs. vs. 10 ± 2 mmHg, P = 0.029) and HR (14 ± 2 vs. 6 ± 2 beats/min, P = 0.033) and a greater reduction in SmO₂ (-54 ± 10 vs. -12 ± 4%, P = 0.001). However, both groups had similar physiological responses to low-intensity, nonpainful plantar flexion exercise. These data suggest that patients with PAD have altered oxygen uptake and/or utilization during fatiguing exercise coincident with an augmented BP response.NEW & NOTEWORTHY In this laboratory study, patients with peripheral artery disease performed plantar flexion exercise in the supine posture until symptoms of claudication occurred. Relative to age- and sex-matched healthy subjects we found that patients had a higher blood pressure response, a higher heart rate response, and a greater reduction in skeletal muscle oxygenation as determined by near-infrared spectroscopy. Our data suggest that muscle ischemia contributes to the augmented exercise pressor reflex in peripheral artery disease.

Efficacy of brief behavioral counselling by allied health professionals to promote physical activity in people with peripheral arterial disease (BIPP): study protocol for a multi-center randomized controlled trial

Background

Physical activity is recommended for people with peripheral arterial disease (PAD), and can improve walking capacity and quality of life; and reduce pain, requirement for surgery and cardiovascular events. This trial will assess the efficacy of a brief behavioral counselling intervention delivered by allied health professionals to improve physical activity in people with PAD.

Methods

This is a multi-center randomised controlled trial in four cities across Australia. Participants (N = 200) will be recruited from specialist vascular clinics, general practitioners and research databases and randomised to either the control or intervention group. Both groups will receive usual medical care, a written PAD management information sheet including advice to walk, and four individualised contacts from a protocol-trained allied health professional over 3 months (weeks 1, 2, 6, 12). The control group will receive four 15-min telephone calls with general discussion about PAD symptoms and health and wellbeing. The intervention group will receive behavioral counselling via two 1-h face-to-face sessions and two 15-min telephone calls. The counselling is based on the 5A framework and will promote interval walking for 3 × 40 min/week. Assessments will be conducted at baseline, and 4, 12 and 24 months by staff blinded to participant allocation. Objectively assessed outcomes include physical activity (primary), sedentary behavior, lower limb body function, walking capacity, cardiorespiratory fitness, event-based claudication index, vascular interventions, clinical events, cardiovascular function, circulating markers, and anthropometric measures. Self-reported outcomes include physical activity and sedentary behavior, walking ability, pain severity, and health-related quality of life. Data will be analysed using an intention-to-treat approach. An economic evaluation will assess whether embedding the intervention into routine care would likely be value for money. A cost-effectiveness analysis will estimate change in cost per change in activity indicators due to the intervention, and a cost-utility analysis will assess change in cost per quality-adjusted life year. A full uncertainty analysis will be undertaken, including a value of information analysis, to evaluate the economic case for further research.

Discussion

This trial will evaluate the efficacy and cost-effectiveness of a brief behavioral counselling intervention for a common cardiovascular disease with significant burden.

Trial registration

ACTRN 12614000592640 Australian New Zealand Clinical Trials Registry. Registration Date 4 June 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3801-7) contains supplementary material, which is available to authorized users.

Coronary Exercise Hyperemia Is Impaired in Patients with Peripheral Arterial Disease

BACKGROUND

Peripheral arterial disease (PAD) is an atherosclerotic vascular disease that affects over 200 million people worldwide. The hallmark of PAD is ischemic leg pain and this condition is also associated with an augmented blood pressure response to exercise, impaired vascular function, and high risk of myocardial infarction and cardiovascular mortality. In this study, we tested the hypothesis that coronary exercise hyperemia is impaired in PAD.

METHODS

Twelve patients with PAD and no overt coronary disease (65 ± 2 years, 7 men) and 15 healthy control subjects (64 ± 2 years, 9 men) performed supine plantar flexion exercise (30 contractions/min, increasing workload). A subset of subjects (n = 7 PAD, n = 8 healthy) also performed isometric handgrip exercise (40% of maximum voluntary contraction to fatigue). Coronary blood velocity in the left anterior descending artery was measured by transthoracic Doppler echocardiography; blood pressure and heart rate were monitored continuously.

RESULTS

Coronary blood velocity responses to 4 min of plantar flexion exercise (PAD: Δ2.4 ± 1.2, healthy: Δ6.0 ± 1.6 cm/sec, P = 0.039) and isometric handgrip exercise (PAD: Δ8.3 ± 4.2, healthy: Δ16.9 ± 3.6, P = 0.033) were attenuated in PAD patients.

CONCLUSION

These data indicate that coronary exercise hyperemia is impaired in PAD, which may predispose these patients to myocardial ischemia.

Nutritional status and body composition in patients with peripheral arterial disease: A cross-sectional examination of disease severity and quality of life

Nutritional and body weight recommendations for cardiovascular diseases are well established, yet there are no equivalent guidelines for peripheral arterial disease (PAD). This cross-sectional study measured the prevalence of cardiovascular-related nutritional and body composition risk factors in sixty PAD patients and their association with PAD severity. A diet that exceeds daily recommended intake of fat and that falls short of recommended intakes of fiber, folate, and vitamin D was associated with increased leg pain and walking difficulty. Increased body fat and waist circumference were associated with diminished walking ability and poorer psychosocial quality of life. Future prospective investigations are merited to inform both PAD clinical care and disease management guidelines.

A Randomized Controlled Trial of Allopurinol in Patients With Peripheral Arterial Disease

Background

Patients with peripheral arterial disease (PAD) are limited by intermittent claudication in the distance they can walk. Allopurinol has been shown in coronary arterial disease to prolong exercise before angina occurs, likely by prevention of oxygen wastage in tissues and reduction of harmful oxidative stress.

Methods

In this study we evaluated whether allopurinol could prolong the time to development of leg pain in participants with PAD. In a double-blind, randomized controlled clinical trial participants were randomized to receive either allopurinol 300 mg twice daily or placebo for 6 months. The primary outcome was change in exercise capacity on treadmill testing at 6 months. Secondary outcomes were 6-minute walking distance, Walking Impairment Questionnaire, SF-36 questionnaire, flow-mediated dilatation, and oxidized low-density lipoprotein. Outcome measures were repeated midstudy and at the end of study. The mean age of the 50 participants was 68.4 ± 1.2 years with 39 of 50 (78%) male.

Results

Five participants withdrew during the study (2 active, 3 placebo). There was a significant reduction in uric acid levels in those who received active treatment of 52.1% (P < 0.001), but no significant change in either the pain-free or the maximum walking distance. Other measures of exercise capacity, blood vessel function, and the participants' own assessment of their health and walking ability also did not change during the course of the study.

Conclusions

Although allopurinol has been shown to be of benefit in a number of other diseases, in this study there was no evidence of any improvement after treatment in patients with PAD.