A Systematic Review of the Uptake and Adherence Rates to Supervised Exercise Programs in Patients with Intermittent Claudication

Home-based Circuit Training and Community Walking for Intermittent Claudication

BACKGROUND

Supervised exercise training is recommended for people with peripheral artery disease (PAD), yet it remains underutilized. Home-based exercise programs (HBEPs) are a potential alternative. The aim of this study was to assess the feasibility of conducting a full scale trial of a 12-week HBEP for people living with symptomatic PAD.

METHODS

In a randomized feasibility trial, patients with intermittent claudication were allocated to either an HBEP or a nonexercise control. The HBEP group was given a Fitbit to use during a 12-week exercise program comprising of personalized step goals and a resistance-based circuit to be undertaken at home twice weekly. The primary outcome was feasibility, assessed via eligibility, recruitment, attrition, tolerability, and adherence. Acceptability was assessed via semistructured interviews. Secondary analysis was undertaken to determine the feasibility of collecting clinical outcome data.

RESULTS

188 people were screened, 133 were eligible (70.7%), 30 were recruited (22.6%) and one withdrew (3.33%). Mean adherence to the daily step goal was 53.5% (range = 29.8-90.5%), and 58.6% of prescribed circuits were completed of which 56.4% were at the desired intensity. Six adverse events were recorded, 3 of which were related to study involvement. No significant differences were observed in exploratory outcomes. Small clinically important differences were seen in walking speed and pain-free treadmill walking distance which should be confirmed or refuted in a larger trial.

CONCLUSIONS

The HBEP was feasible and well tolerated, with successful recruitment and minimal attrition. The intervention was acceptable, with walking seen as more enjoyable than circuit exercise. The WALKSTRONG program may be suitable for those who will not, or cannot, take part in supervised exercise outside of the home.

Extracorporeal Shockwave for Intermittent Claudication and Quality of Life: A Randomized Clinical Trial

Importance

Intermittent lower limb claudication limits function and quality of life. Supervised exercise programs are not readily available, and a noninvasive alternative is needed.

Objective

To assess extracorporeal corporeal shockwave therapy in improving quality of life in patients with claudication.

Design, Setting, and Participants

In this double-blind, placebo-controlled randomized clinical trial, patients in the outpatient setting at a single tertiary center for vascular surgery were randomized in a 1:1 ratio to extracorporeal shockwave therapy or placebo therapy with no shockwaves delivered. Recruitment was between June 2015 and January 2020, with 12-week follow-up ending in March 2020. A convenience sample of patients with claudication and conservative treatment requirements who refused or were unable to participate in supervised exercise were eligible. Patients receiving anticoagulation therapy or with an active cancer were excluded. Of 522 patients screened, 389 were eligible, 138 were enrolled, and 110 completed follow-up and were included in the primary analysis. Statistical analysis was completed by May 2021.

Intervention

In the intervention group, patients received 100 impulses of 0.1mJ/mm/cm2 in an area of the gastrocnemius muscle 3 times weekly for 3 weeks. The steps for treatment were replicated for the control group without delivering the treatment.

Main Outcomes and Measures

The primary outcome was the Physical Functioning domain of the 36-item Short-Form Quality of Life Questionnaire at 12-week follow-up. Secondary outcomes included walking distances, ankle brachial pressure index, and other quality-of-life measures.

Results

Of 138 patients recruited and randomized, 92 (67%) were male, and the mean (SD) age of the study population was 67 (9.6) years. The intervention group had a significantly higher physical function score at 12 weeks (estimated median difference 3.8; 95% CI, 0.0-7.7; P = .03). However, this significance did not remain when adjusting for covariates. At 12 weeks, the intervention group had significantly longer pain-free and maximum walking distances (pain-free estimated median difference, 34.1, 95% CI, 11.4-56.8; P = .004; maximum estimated median difference, 51.4; 95% CI, 10.7-86.5; P = .01).

Conclusions and Relevance

To our knowledge, this is the first double-blind, placebo-controlled, randomized clinical trial to consider extracorporeal shockwave therapy for the management of intermittent claudication. It demonstrated efficacy for walking distances, may have a positive effect on quality of life, and may provide a safe, noninvasive alternative therapy for patients with intermittent claudication.

Trial Registration

ClinicalTrials.gov Identifier: NCT02652078.

Exercise Therapy for Peripheral Artery Disease

PURPOSE OF REVIEW

To summarize evidence regarding exercise treatments for lower extremity peripheral artery disease (PAD).

RECENT FINDINGS

Supervised walking exercise is recommended by practice guidelines for PAD. Supervised treadmill exercise improves treadmill walking distance by approximately 180 m and 6-min walk distance by 30-35 m, compared to control. The Centers for Medicaid and Medicare Services covers 12 weeks of supervised exercise, but most people with PAD do not participate. Home-based walking exercise may be more convenient and accessible than supervised exercise. In randomized clinical trials, home-based walking exercise interventions incorporating behavioral methods, such as accountability to a coach, goal-setting, and self-monitoring, improved 6-min walk distance by 40-54 m, compared to control. Arm and leg ergometry also improved walking endurance for people with PAD, but efficacy compared to walking exercise remains unclear. Walking exercise is first-line therapy for PAD-related walking impairment and can be effective in either a supervised or a structured home-based setting.

High INtensity Interval Training in pATiEnts with Intermittent Claudication: A Qualitative Acceptability Study

BACKGROUND

A novel high-intensity interval training (HIIT) program has demonstrated feasibility for patients with intermittent claudication (IC). The aim of this study was to explore patient perspectives of the HIIT program to inform refinement and future research.

METHODS

All patients screened and eligible for the 'high intensity interval training in patients with intermittent claudication (INITIATE)' study were eligible to take part in a semistructured interview. A convenience subsample of patients was selected from 3 distinct groups: 1) those who completed the HIIT program, 2) those who prematurely discontinued the HIIT program, and 3) those who declined the HIIT program. Interviews considered patients views of the program and experiences of undertaking and/or being invited to undertake it. Interviews were audio recorded, transcribed verbatim, and analyzed via thematic analysis.

RESULTS

Eleven out of 31 participants who completed the program and 12 out of 38 decliners were interviewed. No participants who withdrew from the program agreed to interview. The 3 key themes were; personal reflections of the program; program facilitators and barriers; and perceived benefits. Completers enjoyed taking part, reported symptomatic improvement and would complete it again. Practical and psychological barriers exist, such as transport and motivation. Changes to the program were suggested.

CONCLUSIONS

Findings support the acceptability of this novel HIIT program, which in combination with the feasibility findings, suggest that a fully powered randomized controlled trial, comparing HIIT to usual-care supervised exercise programs is warranted.

Exercise therapy for chronic symptomatic peripheral artery disease

All guidelines worldwide strongly recommend exercise as a pillar of the management of patients affected by lower extremity peripheral artery disease (PAD). Exercise therapy in this setting presents different modalities, and a structured programme provides optimal results. This clinical consensus paper is intended for clinicians to promote and assist for the set-up of comprehensive exercise programmes to best advice in patients with symptomatic chronic PAD. Different exercise training protocols specific for patients with PAD are presented. Data on patient assessment and outcome measures are narratively described based on the current best evidence. The document ends by highlighting disparities in access to supervised exercise programmes across Europe and the series of gaps for evidence requiring further research.

Gamification-augmented home-based exercise for peripheral artery disease: Rationale and design of the GAMEPAD Study

BACKGROUND

Supervised exercise therapy improves walking performance, functional capacity, and quality of life in patients with peripheral artery disease (PAD). However, few patients with PAD are enrolled in supervised exercise programs, and there are a number of logistical and financial barriers to their participation. A home-based walking intervention is likely to be more accessible to patients with PAD, but no fully home-based walking program has demonstrated efficacy. Concepts from behavioral economics have been used to design scalable interventions that increase daily physical activity in patients with atherosclerotic vascular disease, but whether a similar program would be effective in patients with PAD is uncertain.

STUDY DESIGN AND OBJECTIVES

GAMEPAD (NCT04536012) is a pragmatic, virtual, randomized controlled trial designed to evaluate the effectiveness of a gamification strategy informed by concepts from behavioral economics to increase daily physical activity in patients with PAD who are seen in cardiology and vascular surgery clinics affiliated with the University of Pennsylvania Health System. Patients are contacted by email or text message, and complete enrollment and informed consent on the Penn Way to Health online platform. A GAMEPAD substudy will evaluate the effectiveness of opt-in versus opt-out framing when approaching patients for study participation. Patients are then provided with a wearable fitness tracker, establish a baseline daily step count, set a goal to increase daily step count by 33%-50%, and are randomized 1:1 to the gamification or control arms. Interventions continue for 16 weeks, including a 4-week period during which goal step count is gradually increased in the gamification arm, with follow-up for an additional 8 weeks to evaluate the durability of behavior change. The trial has met its enrollment goal of 102 participants, with a primary endpoint of change from baseline in daily steps over the 16-week intervention period. Key secondary endpoints include change from baseline in daily steps over the 8-week postintervention follow-up period and changes in patient-reported measures of PAD symptoms and quality of life over the intervention and follow-up periods.

CONCLUSIONS

GAMEPAD is a virtual, pragmatic randomized clinical trial of a novel, fully home-based walking intervention informed by concepts from behavioral economics to increase physical activity and PAD-specific quality of life in patients with PAD. Its results will have important implications for the application of behavioral economic concepts to scalable home-based strategies to promote physical activity in patients with PAD and other disease processes where physical activity is limited by exertional symptoms.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov; NCT04536012.

Exercise therapy for chronic symptomatic peripheral artery disease

All guidelines worldwide strongly recommend exercise as a pillar in the management of patients affected by lower extremity peripheral artery disease (PAD). Exercise therapy in this setting presents different modalities, and a structured programme provides optimal results. This clinical consensus paper is intended to promote and assist the set up of comprehensive exercise programmes and best advice for patients with symptomatic chronic PAD. Different exercise training protocols specific for patients with PAD are presented. Data on patient assessment and outcome measures are described based on the current best evidence. The document ends by highlighting supervised exercise programme access disparities across Europe and the evidence gaps requiring further research.

Comparison of home-based rehabilitation and a centre-based exercise in terms of functional capacity, muscle oxygenation and quality of life in people with peripheral arterial disease: a protocol for a randomised controlled trial

INTRODUCTION

Peripheral arterial disease (PAD) is increasingly prevalent, and supervised physical exercise programmes are recommended as the first-line treatment. However, these programmes are underused. Alternative delivery models may be able to expand treatment coverage. The objective of this study was to compare a home-based exercise programme (HBEP) and a centre-based exercise (CBE) in terms of their effects on functional capacity, peripheral muscle oxygenation and quality of life in individuals with PAD.

METHODS AND ANALYSIS

This single-blind, parallel randomised clinical trial will consist of two groups: HBEP and CBE. A qualitative analysis will be carried out to investigate acceptability and satisfaction. The primary outcome will be functional capacity, assessed by the incremental shuttle walk test. Secondary outcomes will include functional capacity, assessed by a treadmill walking test; peripheral muscle oxygenation and quality of life; and self-reported functional impairment, risk factors, morbidity, level of physical activity, adherence, acceptability and satisfaction. The intervention protocols will consist of 12 weeks of intermittent walking until claudication symptoms, three times a week. Participants randomly assigned to the CBE group will participate in supervised face-to-face sessions. The HBEP group will perform exercises at home with remote supervision, monitored by a pedometer and heart rate monitor, and subjective perception of effort during each session will be recorded by participants in a training diary; follow-up will be conducted by telephone calls. Statistical analyses will follow the intention-to-treat principle. Participants allocated to the HBEP group will be interviewed about their experience of remote treatment using a qualitative approach.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Ethics Committee of the Universidade Federal de Minas Gerais. The results will be disseminated in a peer-reviewed journal and presented at international congresses. This research has the potential to improve the care of people with PAD because if home-based rehabilitation demonstrates effectiveness, it could be considered an alternative or support resource to the usual centre-based treatment models, expanding access, coverage and participation in vascular physiotherapy TRIAL REGISTRATION: https://ensaiosclinicos.gov.br/rg/RBR-97vy9n7 on 14 April 2022.

Illness beliefs relation to physical activity and quality of life in patients with peripheral arterial disease

Intermittent claudication is the most common symptom of Peripheral Arterial Disease (PAD) and is associated with decreased quality of life (QoL) due to walking impairment. The level of threat attributed to the disease affects QoL and physical activity. This study explores beliefs and illness drawings, and their relationship with quality of life and physical activity in patients undergoing conservative treatment for PAD. A cross-sectional study was carried out including 119 patients with PAD and Intermittent Claudication, in which patients were asked to freely draw their disease and 33 agreed to participate. The profile of beliefs about PAD is characterized by a low level of threat. Belief in the emotional impact of the disease, representations about the consequences and concern about the disease were associated with worse quality of life; the belief of having a high personal control over the disease was associated with more physical activity. The analysis of the disease drawings revealed three categories: extension of the disease (category 1), location and representations of the disease (category 2), and level of detail and complexity of the drawings (category 3). Greater disease extent was associated with more disease symptoms (IPQ 6) (rs = 0.399, p = .021). It is necessary to address beliefs and representations about the disease in consultations with patients with PAD. Patient drawings are a useful, practical, and free tool that does not require a lot of time and can facilitate the approach of health professionals to patient training and education.

Participants' experiences and acceptability of a home-based walking exercise behaviour-change intervention (MOtivating Structure walking Activity in people with Intermittent Claudication (MOSAIC))

OBJECTIVES

This study explored the experiences and acceptability of a novel, home-based, walking exercise behaviour-change intervention (MOtivating Structured walking Activity in people with Intermittent Claudication (MOSAIC)) in adults with Peripheral Arterial Disease (PAD).

DESIGN AND SETTING

Individual semi-structured audio-recorded interviews were conducted with adults with Peripheral Arterial Disease who had completed the MOSAIC intervention as part of a randomised clinical trial. Data were analysed using inductive reflexive thematic analysis and interpreted using the seven-construct theoretical framework of acceptability of healthcare interventions (TFA).

PARTICIPANTS

Twenty participants (mean age (range) 67(54-80) years, 70% male, 55% White British) were interviewed.

RESULTS

One central theme was identified: Acceptability of walking exercise as a treatment. This theme was explained by four linked themes: Exploring walking exercise with a knowledgeable professional, Building confidence with each step, Towards self-management-learning strategies to continue walking and The impact of walking exercise. These themes were interpreted using six of the seven TFA constructs: affective attitude, burden, perceived effectiveness, intervention coherence, opportunity costs, and self-efficacy.

CONCLUSIONS

Participants perceived MOSAIC as an effective, acceptable, and low burden intervention. Physiotherapists were regarded as knowledgeable and supportive professionals who helped participants understand PAD and walking exercise as a treatment. Participants developed confidence to self-manage their condition and their symptoms. As participants confidence and walking capacity improved, they expanded their activities and gained a more positive outlook on their future. MOSAIC is an acceptable intervention that may facilitate adoption of and access to exercise for people with PAD.

IMPLICATIONS FOR PRACTICE

Supervised Exercise Therapy for Intermittent Claudication: A Propensity Score Matched Analysis of Retrospective Data on Long Term Cardiovascular Outcomes

OBJECTIVE

This study aimed to explore the long term outcomes of patients with intermittent claudication (IC) who completed supervised exercise therapy (SET) vs. those who declined or prematurely discontinued SET, focusing on the incidence of chronic limb threatening ischaemia (CLTI), revascularisation, major adverse limb events (MALE), and major adverse cardiovascular events (MACE).

METHODS

A retrospective registry analysis of consecutive patients with IC who were referred for SET between March 2015 and August 2016 and followed up for a minimum of five years. Serial univariable analysis and logistic regression were performed to identify the statistically significant clinical variables that were independent predictors of each outcome measure. The resulting statistically significant variables were used to guide 1:1 propensity score matching (PSM) using the nearest neighbour method with a calliper of 0.2. Cox proportional hazards regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association between SET and the outcomes of interest.

RESULTS

Two hundred and sixty-six patients were referred to SET between March 2015 and August 2016. Of these, 64 patients completed SET and 202 patients did not. After PSM, 49 patients were analysed in each cohort. The Cox proportional hazards analysis revealed a significant association between completion of SET and revascularisation requirement (HR 0.46 95% CI 0.25 - 0.84; p = .011), completion of SET and progression to CLTI (HR 0.091, 95% CI 0.04 - 0.24; p < .001), completion of SET and MACE (HR 0.52; 95% CI 0.28 - 0.99; p = .05) and completion of SET and MALE (HR 0.28, 95% CI 0.13 - 0.65; p = .003). The Harrell's C index for all of these models was greater than 0.75, indicating good predictive accuracy.

CONCLUSION

Completion of SET is associated with better outcomes in patients who completed SET compared with patients who declined or discontinued SET with respect to clinically important cardiovascular outcomes over seven years.

Exercise Therapy for Chronic Symptomatic Peripheral Artery Disease: A Clinical Consensus Document of the European Society of Cardiology Working Group on Aorta and Peripheral Vascular Diseases in Collaboration With the European Society of Vascular Medicine and the European Society for Vascular Surgery

All guidelines worldwide strongly recommend exercise as a pillar in the management of patients affected by lower extremity peripheral artery disease (PAD). Exercise therapy in this setting presents different modalities, and a structured programme provides optimal results. This clinical consensus paper is intended to promote and assist the set up of comprehensive exercise programmes and best advice for patients with symptomatic chronic PAD. Different exercise training protocols specific for patients with PAD are presented. Data on patient assessment and outcome measures are described based on the current best evidence. The document ends by highlighting supervised exercise programme access disparities across Europe and the evidence gaps requiring further research.

Mobile health technologies to improve walking distance in people with intermittent claudication

BACKGROUND

Peripheral arterial disease (PAD) is the obstruction or narrowing of the large arteries of the lower limbs, which can result in impaired oxygen supply to the muscle and other tissues during exercise, or even at rest in more severe cases. PAD is classified into five categories (Fontaine classification). It may be asymptomatic or various levels of claudication pain may be present; at a later stage, there may be ulceration or gangrene of the limb, with amputation occasionally being required. About 20% of people with PAD suffer from intermittent claudication (IC), which is muscular discomfort in the lower extremities induced by exertion and relieved by rest within 10 minutes; IC causes restriction of movement in daily life. Treatment for people with IC involves addressing lifestyle risk factors. Exercise is an important part of treatment, but supervised exercise programmes for individuals with IC have low engagement levels and high attrition rates. The use of mobile technologies has been suggested as a new way to engage people with IC in walking exercise interventions. The novelty of the intervention, low cost for the user, automation, and ease of access are some of the advantages mobile health (mhealth) technologies provide that give them the potential to be effective in boosting physical activity in adults.

OBJECTIVES

To assess the benefits and harms of mobile health (mhealth) technologies to improve walking distance in people with intermittent claudication.

SEARCH METHODS

The Cochrane Vascular Information Specialist conducted systematic searches of the Cochrane Vascular Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and CINAHL, and also searched the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov. The most recent searches were carried out on 19 December 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in people aged 18 years or over with symptomatic PAD and a clinical diagnosis of IC. We included RCTs comparing mhealth interventions to improve walking distance versus usual care (no intervention or non-exercise advice), exercise advice, or supervised exercise programmes. We excluded people with chronic limb-threatening ischaemia (Fontaine III and IV).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were change in absolute walking distance from baseline, change in claudication distance from baseline, amputation-free survival, revascularisation-free survival. Our secondary outcomes were major adverse cardiovascular events, major adverse limb events, above-ankle amputation, quality of life, and adverse events. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included four RCTs involving a total of 614 participants with a clinical diagnosis of IC. The duration of intervention of the four included RCTs ranged from 3 to 12 months. Participants were randomised to either mhealth or control (usual care or supervised exercise programme). All four studies had an unclear or high risk of bias in one or several domains. The most prevalent risk of bias was in the area of performance bias, which was rated high risk as it is not possible to blind participants and personnel in this type of trial. Based on GRADE criteria, we downgraded the certainty of the evidence to low, due to concerns about risk of bias, imprecision, and clinical inconsistency. Comparing mhealth with usual care, there was no clear evidence of an effect on absolute walking distance (mean difference 9.99 metres, 95% confidence interval (CI) -27.96 to 47.93; 2 studies, 503 participants; low-certainty evidence). None of the included studies reported on change in claudication walking distance, amputation-free survival, or revascularisation-free survival. Only one study reported on major adverse cardiovascular events (MACE) and found no clear difference between groups (risk ratio 1.37, 95% CI 0.07 to 28.17; 1 study, 305 participants; low-certainty evidence). None of the included studies reported on major adverse limb events (MALE) or above-ankle amputations.

AUTHORS' CONCLUSIONS

Mobile health technologies can be used to provide lifestyle interventions for people with chronic conditions, such as IC. We identified a limited number of studies that met our inclusion criteria. We found no clear difference between mhealth and usual care in improving absolute walking distance in people with IC; however, we judged the evidence to be low certainty. Larger, well-designed RCTs are needed to provide adequate statistical power to reliably evaluate the effects of mhealth technologies on walking distance in people with IC.

Tailored risk assessment and forecasting in intermittent claudication

BACKGROUND

Guidelines recommend cardiovascular risk reduction and supervised exercise therapy as the first line of treatment in intermittent claudication, but implementation challenges and poor patient compliance lead to significant variation in management and therefore outcomes. The development of a precise risk stratification tool is proposed through a machine-learning algorithm that aims to provide personalized outcome predictions for different management strategies.

METHODS

Feature selection was performed using the least absolute shrinkage and selection operator method. The model was developed using a bootstrapped sample based on patients with intermittent claudication from a vascular centre to predict chronic limb-threatening ischaemia, two or more revascularization procedures, major adverse cardiovascular events, and major adverse limb events. Algorithm performance was evaluated using the area under the receiver operating characteristic curve. Calibration curves were generated to assess the consistency between predicted and actual outcomes. Decision curve analysis was employed to evaluate the clinical utility. Validation was performed using a similar dataset.

RESULTS

The bootstrapped sample of 10 000 patients was based on 255 patients. The model was validated using a similar sample of 254 patients. The area under the receiver operating characteristic curves for risk of progression to chronic limb-threatening ischaemia at 2 years (0.892), risk of progression to chronic limb-threatening ischaemia at 5 years (0.866), likelihood of major adverse cardiovascular events within 5 years (0.836), likelihood of major adverse limb events within 5 years (0.891), and likelihood of two or more revascularization procedures within 5 years (0.896) demonstrated excellent discrimination. Calibration curves demonstrated good consistency between predicted and actual outcomes and decision curve analysis confirmed clinical utility. Logistic regression yielded slightly lower area under the receiver operating characteristic curves for these outcomes compared with the least absolute shrinkage and selection operator algorithm (0.728, 0.717, 0.746, 0.756, and 0.733 respectively). External calibration curve and decision curve analysis confirmed the reliability and clinical utility of the model, surpassing traditional logistic regression.

CONCLUSION

The machine-learning algorithm successfully predicts outcomes for patients with intermittent claudication across various initial treatment strategies, offering potential for improved risk stratification and patient outcomes.

Pre-participation Withdrawal and Noncompletion of Cardiac Rehabilitation in Peripheral Artery Disease: MATCHED COMPARISONS TO CORONARY ARTERY DISEASE

PURPOSE

Despite the mortality benefit of cardiac rehabilitation (CR) participation, as well as its cost-effectiveness for people with peripheral artery disease (PAD), there are limited data on adherence and completion of CR in those with and without concomitant coronary artery disease (CAD). The objective of this study was to compare CR pre-participation withdrawal and noncompletion between patients with PAD and concomitant PAD and CAD (PAD/CAD) versus matched and unmatched patients with CAD (uCAD).

METHODS

Consecutively referred patients between 2006-2017 with PAD (n = 271) and PAD/CAD (n = 610) were matched to CAD by age, sex, diabetes, smoking status, and referral year. The uCAD (n = 14 487) group was included for comparison. Reasons for withdrawal were ascertained by interview.

RESULTS

There were no significant differences in pre-participation withdrawal between PAD and matched CAD (46 vs 43%, P = .49), nor in noncompletion (22 vs 18%, P = .28). Results were similar for PAD/CAD and matched CAD (withdrawal: 36 vs 34%, P = .37) and (noncompletion: 25 vs 23%, P = .46). A smaller proportion of patients with uCAD withdrew (28%) than patients with PAD ( P < .001) and PAD/CAD ( P < .001), with no difference in noncompletion ( P > .40, both). There were no differences between PAD and PAD/CAD and their matched counterparts for medical and nonmedical reasons for withdrawal and noncompletion ( P ≥ .25, all).

CONCLUSION

Pre-participation withdrawal rates were similar between patients with PAD, PAD/CAD, and their matched cohorts but greater than patients with uCAD. Once patients started CR, there were similar completion rates among all groups. Reports that patients with PAD are less likely to start CR may be related to their complex medical profile rather than PAD alone. Strategies to improve participation among patients with PAD should focus on the immediate post-referral period.

Low-intensity resistance exercise with blood flow restriction for patients with claudication: A randomized controlled feasibility trial

BACKGROUND

Claudication is a common and debilitating symptom of peripheral artery disease, resulting in poor exercise performance and quality of life (QoL). Supervised exercise programs are an effective rehabilitation for patients with claudication, but they are poorly adhered to, in part due to the high pain and effort associated with walking, aerobic, and resistance exercise. Low-intensity resistance exercise with blood flow restriction (BFR) represents an alternative exercise method for individuals who are intolerant to high-intensity protocols. The aim of this study was to evaluate the feasibility of a supervised BFR program in patients with claudication.

METHODS

Thirty patients with stable claudication completed an 8-week supervised exercise program and were randomized to either BFR (n = 15) or a control of matched exercise without BFR (control; n = 15). Feasibility, safety, and efficacy were assessed.

RESULTS

All success criteria of the feasibility trial were met. Exercise adherence was high (BFR = 78.3%, control = 83.8%), loss to follow up was 10%, and there were no adverse events. Clinical improvement in walking was achieved in 86% of patients in the BFR group but in only 46% of patients in the control group. Time to claudication pain during walking increased by 35% for BFR but was unchanged for the control. QoL for the BFR group showed improved mobility, ability to do usual activities, pain, depression, and overall health at follow up.

CONCLUSION

A supervised blood flow restriction program is feasible in patients with claudication and has the potential to increase exercise performance, reduce pain, and improve QoL. (Clinicaltrials.gov Identifier: NCT04890275).

Neuromuscular Electrical Stimulation for Intermittent Claudication (NESIC): multicentre, randomized controlled trial

METHODS

This was an open, multicentre, randomized controlled trial. Patients with intermittent claudication attending vascular surgery outpatient clinics were randomized (1:1) to receive either neuromuscular electrical stimulation (NMES) or not in addition to local standard care available at study centres (best medical therapy alone or plus supervised exercise therapy (SET)). The objective of this trial was to investigate the clinical efficacy of an NMES device in addition to local standard care in improving walking distances in patients with claudication. The primary outcome was change in absolute walking distance, measured by a standardized treadmill test at 3 months. Secondary outcomes included intermittent claudication (IC) distance, adherence, quality of life, and haemodynamic changes.

RESULTS

Of 200 participants randomized, 160 were included in the primary analysis (intention to treat, Tobit regression model). The square root of absolute walking distance was analysed (due to a right-skewed distribution) and, although adjunctive NMES improved it at 3 months, no statistically significant effect was observed. SET as local standard care seemed to improve distance compared to best medical therapy at 3 months (3.29 units; 95 per cent c.i., 1.77 to 4.82; P < 0.001). Adjunctive NMES improved distance in mild claudication (2.88 units; 95 per cent c.i., 0.51 to 5.25; P = 0.02) compared to local standard care at 3 months. No serious adverse events relating to the device were reported.

CONCLUSION

Supervised exercise therapy is effective and NMES may provide further benefit in mild IC.This trial was supported by a grant from the Efficacy and Mechanism Evaluation Program, a Medical Research Council and National Institute for Health and Care Research partnership. Trial registration: ISRCTN18242823.

Multimodal prehabilitation for peripheral arterial disease patients with intermittent claudication - A pilot randomized controlled trial

OBJECTIVE

To establish the feasibility and safety of multimodal prehabilitation (MP), and to obtain pilot data on the change in quality of life, functional walking capacity, and the need for surgery for a full-scale trial.

DESIGN

Pilot randomized controlled trial that included patients older than 50 years old suffering from moderate to severe intermittent claudication and who were candidates for endovascular revascularization (ER). Participants were excluded if they presented with ischemic rest pain, gangrene or ulceration of the index leg, significant lesions in the iliac vessels, planned surgical bypass, comorbidities in which exercise was contraindicated or if they were unable to speak English or French.

METHODS

Participants were randomized in a 1:1 ratio to 12 weeks of MP or institutional standard of care (unsupervised walking advice). MP consisted of i)1 weekly supervised exercise session; ii) home-based exercise prescription; iii) nutritional counseling and supplementation iv) smoking cessation therapy and v) psychosocial support. Feasibility and safety were measured with recruitment and retention rates, as well as the occurrence of any adverse events. In addition, barriers to attend supervised sessions and compliance to each component were assessed. Change in functional walking capacity, health-related quality of life, and the rates of patients deciding not to undergo ER were collected and analyzed throughout the follow-up period of 12 months.

RESULTS

Of the 37 patients referred for eligibility, 27 (73%) accepted to participate in the trial and were randomized. Of the 27 patients included, 24 completed the 12-week program. Adherence to each prehabilitation component was 83% IQR [72,93] for supervised exercise, 90% [83,96] for home-based exercise and 69% [45,93] for nutritional sessions. 50% of patients were referred for and underwent psychosocial intervention and 40% of the active smokers enrolled in the smoking cessation program. No adverse events were observed during the program. The two main barriers for not fully adhering to the intervention were excessive pain while performing the exercises and the difficulty to keep up with the prescribed exercises. A statistically significant mean change (SD) was seen in the MP group vs standard of care for functional capacity, mean (SD) 6MWT 60 (74) vs -11 (40) meters p<0.05, and quality of life mean (SD) VascuQol 1.15 (0.54) vs -0.3 (1.09) points p<0.05. There was no statistically significant difference between groups in the rates of patients deciding to undergo ER during the 1-year follow-up period.

CONCLUSIONS

The results of this pilot trial demonstrate that MP is safe and feasible. A 12-week MP program seems to improve quality of life and functional walking capacity to a greater extent than unsupervised walking advice. There is a need for a large-scale trial to investigate the effectiveness of MP at improving quality of life and assessing its impact on the rates of patients deciding not to undergo or delay ER. The long-term functional and quality of life outcomes of the patients deciding to undergo ER after prehabilitation also needs to be assessed.

Effects of Long-Term Home Exercise in Participants With Peripheral Artery Disease

Background This randomized controlled trial compared long-term changes in peak walking time (PWT) and exercise time-to-minimum calf muscle oxygen saturation (StO2) in symptomatic participants with peripheral artery disease following a long-term home exercise program (HEP), a short-term supervised exercise therapy (SET) program that transitioned to a long-term HEP (SET/HEP), and a control intervention. Methods and Results For the first 3 months, HEP and SET/HEP groups performed intermittent walking to mild-to-moderate claudication pain, whereas the control group performed light resistance training. For the subsequent 15 months, the HEP group continued their exercise program, the SET/HEP group transitioned from SET to the HEP program, and the control group transitioned to only receive walking advice. PWT increased significantly from baseline to month 18 in the HEP group (408±279 meters to 814±393 meters, P<0.001) and in the SET/HEP group (457±288 meters to 818±313 meters, P<0.001). Exercise time-to-minimum calf muscle StO2 increased significantly from baseline to month 18 in the HEP group (238±241 seconds to 497±485 seconds, P<0.05) and in the SET/HEP group (296±289 seconds to 620±450 seconds, P<0.001). These changes in PWT and exercise time-to-minimum calf muscle StO2 were greater than in the control group (P<0.001 and P<0.01, respectively). Additionally, the change in exercise time-to-minimum calf muscle StO2 was correlated with the change in PWT in both exercise groups combined (r=0.601, P=0.0015). Conclusions Long-term HEP and SET/HEP were efficacious in improving PWT and exercise time-to-minimum calf muscle StO2 in symptomatic participants with peripheral artery disease, and these changes were correlated with each other. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00618670.

Pathology, Progression, and Emerging Treatments of Peripheral Artery Disease-Related Limb Ischemia

PURPOSE

This narrative review summarizes recent research examining treatment targets for peripheral artery disease (PAD)-related limb ischemia.

METHODS

Targeted searches of the PubMed and clinical trial registry databases were performed to identify recent findings from animal models of limb ischemia and clinical studies examining PAD progression and treatment. Ongoing clinical trials testing new treatments for PAD were also reviewed. Relevant full-text articles were retrieved and critically reviewed. Where indicated, data were tabulated and summarized in the text.

FINDINGS

Most people with PAD need treatment to improve their walking and function and limit leg pain. Currently, the available treatments of cilostazol, exercise therapy, and revascularization have several deficiencies, including limited access, poor uptake, limited efficacy, and risk of complications. Severe PAD threatens limb viability and is treated by endovascular or open surgical revascularization but is not always successful in achieving limb salvage. Research is ongoing to develop and test new therapies, including new exercise programs, drugs, stem cell treatments and RNA therapeutics, so that new and adjunctive PAD treatments can be offered. Results from multiple clinical trials are expected within the next 5 years.

IMPLICATIONS

It is envisaged that a range of new therapies for PAD will be available in the future.

Time-course evolution of functional performance during a 3-month supervised exercise training program in patients with symptomatic peripheral artery disease

INTRODUCTION

Functional performance is impaired in patients with peripheral artery disease (PAD). The effects of a supervised exercise training (SET) program on functional performance have yet to be clearly determined. The aim was to investigate the time-course evolution of functional performance during a 3-month SET program.

METHODS

Patients with chronic symptomatic PAD participating in a 3-month SET program were investigated. Six-minute walking distance (6MWD), the stair climbing test (SCT), and the Short Physical Performance Battery (SPPB) were assessed before SET, after the first and second months of SET, and following the SET program. The ankle- and toe-brachial indices were measured before and after the SET program.

RESULTS

Ninety patients with PAD (age 65.4 ± 10.2 years) were analyzed. The 6MWD significantly improved after the first (+7%, p ⩽ 0.001) and second months (+13%, p ⩽ 0.001) and following SET (+14%, p ⩽ 0.001) compared to before the SET program. The 6MWD significantly improved after the 2nd month (+6%, p ⩽ 0.001) and following SET (+7%, p ⩽ 0.001) compared to after the first month of the SET program. The SPPB score and SCT performance significantly improved after the first (SPPB score: +9%, p ⩽ 0.001; SCT: +17%, p ⩽ 0.001) and second months (SPPB score: +11%, p ⩽ 0.001; SCT: +24%, p ⩽ 0.001) and following SET (SPPB score: +12%, p ⩽ 0.001; SCT: +25%, p ⩽ 0.001) compared to before the SET program. No significant differences were observed following SET compared to the second month of the SET program. Vascular parameters did not change significantly.

CONCLUSIONS

A 3-month SET program improves several components of functional performance, and adaptations mainly occur during the 1st and 2nd months of the SET program.

High-intensity interval training in patients with intermittent claudication

OBJECTIVE

Provision, uptake, adherence, and completion rates for supervised exercise programs (SEP) for intermittent claudication (IC) are low. A shorter, more time-efficient, 6-week, high-intensity interval training (HIIT) program may be an effective alternative that is more acceptable to patients and easier to deliver. The aim of this study was to determine the feasibility of HIIT for patients with IC.

METHODS

A single arm proof-of-concept study, performed in secondary care, recruiting patients with IC referred to usual-care SEPs. Supervised HIIT was performed three times per week for 6 weeks. The primary outcome was feasibility and tolerability. Potential efficacy and potential safety were considered, and an integrated qualitative study was undertaken to consider acceptability.

RESULTS

A total of 280 patients were screened: 165 (59%) were eligible, and 40 (25%) were recruited. The majority (n = 31; 78%) of participants completed the HIIT program. The remaining nine patients were withdrawn or chose to withdraw. Completers attended 99% of training sessions, completed 85% of sessions in full, and performed 84% of completed intervals at the required intensity. There were no related serious adverse events. Maximum walking distance (+94 m; 95% confidence interval, 66.6-120.8 m) and the SF-36 physical component summary (+2.2; 95% confidence interval, 0.3-4.1) were improved following completion of the program.

CONCLUSIONS

Uptake to HIIT was comparable to SEPs in patients with IC, but completion rates were higher. HIIT appears feasible, tolerable, and potentially safe and beneficial for patients with IC. It may provide a more readily deliverable, acceptable form of SEP. Research comparing HIIT with usual-care SEPs appears warranted.

The Mechanism of Effort Intolerance in Patients with Peripheral Arterial Disease: A Combined Stress Echocardiography and Cardiopulmonary Exercise Test

AIM

We used a combined stress echocardiography and cardiopulmonary exercise test (CPET) to explore effort intolerance in peripheral arterial disease (PAD) patients.

METHODS

Twenty-three patients who had both PAD and coronary artery disease (CAD) were compared with twenty-four sex- and age-matched CAD patients and fifteen normal controls using a symptom-limited ramp bicycle CPET on a tilting dedicated ergometer. Echocardiographic images were obtained concurrently with gas exchange measurements along predefined stages of exercise. Oxygen extraction was calculated using the Fick equation at each activity level.

RESULTS

Along the stages of exercise (unloaded; anaerobic threshold; peak), in PAD + CAD patients compared with CAD or controls, diastolic function worsened (p = 0.051 and p = 0.013, respectively), and oxygen consumption (p < 0.001 and p < 0.001, respectively) and oxygen pulse (p = 0.0024 and p = 0.0027, respectively) were reduced. Notably, oxygen pulse was blunted due to an insufficient increase in both stroke volume (p = 0.025 and p = 0.028, respectively) and peripheral oxygen extraction (p = 0.031 and p = 0.038, respectively). Chronotropic incompetence was more prevalent in PAD patients and persisted after correction for beta-blocker use (62% vs. 42% and 11%, respectively).

CONCLUSIONS

In PAD patients, exercise limitation is associated with diastolic dysfunction, chronotropic incompetence and peripheral factors.

Peripheral Artery Disease: Treatment of Claudication and Surgical Management

Peripheral artery disease (PAD) affects approximately 230 million people worldwide and is associated with an increased risk of major adverse cardiovascular and limb events. Even though this condition is considered a cardiovascular equivalent, it remains an under-recognized and under-treated entity. Anti-platelet and statin therapy, along with smoking cessation, are the foundations of therapy to reduce adverse events but are challenging to fully implement in this patient population. Race and socioeconomic status also have profound impacts on PAD outcomes. Exercise therapy is the gold standard treatment of claudication while revascularization procedures are often reserved for patients with limb-threatening ischemia.

Transcriptomic and Proteomic of Gastrocnemius Muscle in Peripheral Artery Disease

BACKGROUND

Few effective therapies exist to improve lower extremity muscle pathology and mobility loss due to peripheral artery disease (PAD), in part because mechanisms associated with functional impairment remain unclear.

METHODS

To better understand mechanisms of muscle impairment in PAD, we performed in-depth transcriptomic and proteomic analyses on gastrocnemius muscle biopsies from 31 PAD participants (mean age, 69.9 years) and 29 age- and sex-matched non-PAD controls (mean age, 70.0 years) free of diabetes or limb-threatening ischemia.

RESULTS

Transcriptomic and proteomic analyses suggested activation of hypoxia-compensatory mechanisms in PAD muscle, including inflammation, fibrosis, apoptosis, angiogenesis, unfolded protein response, and nerve and muscle repair. Stoichiometric proportions of mitochondrial respiratory proteins were aberrant in PAD compared to non-PAD, suggesting that respiratory proteins not in complete functional units are not removed by mitophagy, likely contributing to abnormal mitochondrial activity. Supporting this hypothesis, greater mitochondrial respiratory protein abundance was significantly associated with greater complex II and complex IV respiratory activity in non-PAD but not in PAD. Rate-limiting glycolytic enzymes, such as hexokinase and pyruvate kinase, were less abundant in muscle of people with PAD compared with non-PAD participants, suggesting diminished glucose metabolism.

CONCLUSIONS

In PAD muscle, hypoxia induces accumulation of mitochondria respiratory proteins, reduced activity of rate-limiting glycolytic enzymes, and an enhanced integrated stress response that modulates protein translation. These mechanisms may serve as targets for disease modification.

The Ability to Look Beyond: The Treatment of Peripheral Arterial Disease

This paper offers a practical overview of the contemporary management of patients with peripheral arterial disease presenting intermittent claudication (IC), including clinical and instrumental diagnosis, risk factors modification, medical management, and evidence-based revascularization indications and techniques. Decision making represents a crucial element in the management of the patient with IC; for this, we think a review of this type could be very useful, especially for non-vascular specialists.

Physical Performance and Skeletal Muscle Transcriptional Adaptations Are Not Impacted by Exercise Training Frequency in Mice with Lower Extremity Peripheral Artery Disease

Exercise training is an important therapeutic strategy for lower extremity peripheral artery disease (PAD). However, the effects of different exercise frequency on physiological adaptations remain unknown. Thus, this study compared the effects of a 7-week moderate-intensity aerobic training performed either three or five times/week on skeletal muscle gene expression and physical performance in mice with PAD. Hypercholesterolemic male ApoE-deficient mice were subjected to unilateral iliac artery ligation and randomly assigned to sedentary or exercise training regimens either three or five times/week. Physical performance was assessed using a treadmill test to exhaustion. Expression of genes related to glucose and lipid metabolism, mitochondrial biogenesis, muscle fiber-type, angiogenesis, and inflammation was analyzed in non-ischemic and ischemic gastrocnemius muscles by real-time polymerase chain reaction. Physical performance was improved to the same extent in both exercise groups. For gene expression patterns, no statistical differences were observed between three or five times/week exercised mice, both in the non-ischemic and ischemic muscles. Our data show that exercising three to five times a week induces similar beneficial effects on performance. Those results are associated with muscular adaptations that remain identical between the two frequencies.

Effect of Brief Counseling by Allied Health Professionals on Step Count of People With Peripheral Artery Disease: A Randomized Clinical Trial

Importance

It is unclear how to effectively promote walking in people with peripheral artery disease (PAD).

Objective

To test whether brief counseling delivered by allied health professionals increases step count in participants with PAD.

Design, Setting, and Participants

In this randomized clinical trial, participants with symptomatic PAD were recruited from sites in Australia and randomly allocated 1:1 to the counseling intervention or an attention control. Data were collected from January 2015 to July 2021, and data were analyzed from March to November 2022.

Interventions

Two 1-hour face-to-face and two 15-minute telephone counseling sessions designed to increase walking.

Main Outcomes and Measures

The primary outcome was the between-group difference in change in daily step count estimated by accelerometer recordings over 7 days at baseline and 4 months, using imputation for missing values. Other outcomes at 4, 12, and 24 months included step count, 6-minute walk distance, and disease-specific and generic measures of health-related quality of life. Risk of major adverse limb events was assessed over 24 months.

Results

Of 200 included participants, 144 (72.0%) were male, and the mean (SD) age was 69.2 (9.3) years. The planned sample of 200 participants was allocated to the counseling intervention group (n = 102) or attention control group (n = 98). Overall, 198 (99.0%), 175 (87.5%), 160 (80.0%) and 143 (71.5%) had step count assessed at entry and 4, 12, and 24 months, respectively. There was no significant between-group difference in the primary outcome of change in daily step count over 4 months (mean steps, 415; 95% CI, -62 to 893; P = .07). Participants in the counseling group had significantly greater improvement in the secondary outcome of disease-specific Intermittent Claudication Questionnaire score at 4 months (3.2 points; 95% CI, 0.1-6.4; P = .04) and 12 months (4.3 points; 95% CI, 0.5-8.1; P = .03) but not at 24 months (1.2 points; 95% CI, -3.1 to 5.6; P = .57). Findings were similar for mean PAD Quality of Life Questionnaire component assessing symptoms and limitations in physical functioning (4 months: 1.5 points; 95% CI, 0.3-2.8; P = .02; 12 months: 1.8 points; 95% CI, 0.3-3.3; P = .02; 24 months: 1.3 points; 95% CI. -0.5 to 3.1; P = .16). There was no significant effect of the intervention on change in mean 6-minute walking distance (4 months: 9.3 m; 95% CI, -3.7 to 22.3; P = .16; 12 months: 13.8 m; 95% CI, -4.2 to 31.7; P = .13; 24 months: 1.2 m; 95% CI, -20.0 to 22.5; P = .91). The counseling intervention did not affect the rate of major adverse limb events over 24 months (12 [6.0%] in the intervention group vs 11 [5.5%] in the control group; P > .99).

Conclusions and Relevance

This randomized clinical trial found no significant effect of brief counseling on step count in people with PAD. Alternate interventions are needed to enable walking.

Trial Registration

Australian New Zealand Clinical Trials Registry Identifier: ACTRN12614000592640.

Evaluation of the Effects of Extracorporeal Shockwave Therapy in Patients With Peripheral Arterial Disease: A Meta-Analysis of Randomized Control Trials

The aim of this meta-analysis is to assess the efficacy of extracorporeal shockwave therapy (ESWT) in patients with peripheral arterial disease (PAD). This meta-analysis was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search was conducted independently by two authors using PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) from inception to January 15, 2023. Primary clinical outcomes assessed in this meta-analysis were changes in maximum waking distance (MWD) and pain-free walking distance (PFWD) from baseline. Other outcomes assessed included change in ankle brachial pressure index (ABI) and degree of arterial stenosis. Four RCTs involving a total of 228 patients were included. Change of PFWD and MWD from baseline was significantly higher in patients randomized in the ESWT group as compared to the control group. No significant differences were reported between the two groups in terms of change in ABI from baseline. In conclusion, this meta-analysis of four randomized controlled trials found evidence that ESWT is an effective treatment for patients with PAD in terms of improving PFWD and MWD and reducing stenosis. However, there was no significant difference in the improvement of the ankle-brachial index between the study groups.

Barriers to participation in supervised exercise therapy reported by people with peripheral artery disease

OBJECTIVE

This study identified barriers to participation in supervised exercise therapy covered by the Centers for Medicare and Medicaid Services (CMS), reported by people with lower extremity peripheral artery disease (PAD).

METHODS

People with PAD participating in research studies of walking impairment due to PAD in the Chicagoland area were asked to complete a questionnaire between March 15, 2019, and July 12, 2022, assessing their experience and attitudes about supervised exercise therapy. Participants were identified using mailed postcards to people aged 50 and older in Chicagoland, from medical centers in Chicago, and using bus and train advertisements. The questionnaire was developed based on focus group feedback from people with PAD.

RESULTS

Of 516 participants with PAD approached, 489 (94.8%) completed the questionnaire (mean age: 71.0 years [standard deviation: 8.7], mean ankle-brachial index: 0.71 [standard deviation: 0.25]; 204 [41.7%] women and 261 [53.4%] Black). Of the 489 participants, 416 (85.1%) reported that their physician had never prescribed or recommended supervised exercise therapy. Overall, 357 (73.2%) reported willingness to travel three times weekly to the medical center for supervised exercise participation. However, of these, 214 (59.9%) reported that they were unwilling or unable to pay the $11 per exercise session copay required for supervised exercise covered by CMS. Of 51 people with PAD who reported prior participation in supervised exercise, only 5 (9.8%) completed the 12 weeks of supervised exercise therapy covered by CMS and 29 (56.9%) completed 6 or fewer weeks. Of 131 (26.8%) unwilling to travel three times weekly to a center for supervised exercise, the most common reasons for unwillingness to participate were "too time-consuming" (55.0%), "too inconvenient" (45.8%), and "lack of interest in treadmill exercise" (28.2%).

CONCLUSIONS

Approximately 2 to 4 years after CMS began covering supervised exercise for PAD, most people with PAD in this study from a large urban area had not participated in supervised exercise therapy. Of those who participated, most completed fewer than half of the sessions covered by CMS. The required CMS copayment was a common barrier to supervised exercise participation by people with PAD.

Patient and Healthcare Professional Priorities for a Mobile Phone Application for Patients With Peripheral Arterial Disease

Introduction Supervised exercise therapy (SET) is the first-line treatment for the peripheral arterial disease (PAD), however, access and compliance are low. An alternative method of delivering this therapy is through mobile health applications, which can be more accessible and convenient for patients. The aim of this study is to evaluate patient, public and healthcare professional (HCP) priorities with regard to a dedicated mobile phone application to deliver remote SET. Methods Bespoke questionnaires were designed for patients and HCPs to assess app functionality and prioritisations for development. These were distributed through social media and the Norfolk and Norwich University Hospital. Results Functionality questionnaires were completed by 62 patients and 44 HCPs. Eighty-four per cent of patients wanted their therapy to be monitored by their vascular team with the majority (78%) interested in measuring walking distances. Most patients (76%) were interested in watching exercise videos. These views were shared by HCPs. A communication platform was prioritised for messaging and pictures by the patient (74% and 68% respectively), but not so by HCPs (40%). Documenting other forms of physical activity and the use of wearable technology was less valuable to patients but favoured by HCPs (50%). The ability to interact with other users was not prioritised by either group. Conclusion Delivery of a mobile phone application to deliver health programmes for SET in patients with PAD is an acceptable method for patients and HCPs. This data will enable the next stages of mobile phone application development to be appropriately prioritised, focusing on building exercise videos, a communication platform and further walking tests.

Attendance at Supervised Exercise Sessions and Walking Outcomes in Peripheral Artery Disease: Results From 2 Randomized Clinical Trials

Background Supervised exercise therapy (SET) is the first-line therapy for walking impairment in peripheral artery disease (PAD). This study evaluated the association between attendance at SET and improved walking performance, compared with a control group, in PAD. Methods and Results Data from 2 randomized clinical trials of SET for PAD were combined. In each trial, participants were randomized to 3 times weekly supervised treadmill exercise or an attention control group for 6 months (maximum, 77 exercise sessions). Participants randomized to SET were categorized into tertiles, according to the proportion of exercise sessions they attended. Results adjusted for age, sex, race, baseline walking performance, comorbidities, and other potential confounders. A total of 272 participants with PAD (mean age, 67.9±9.3 years; 44% women; 61% Black race) were included. For participants randomized to SET, tertiles of attendance rates at exercise sessions were as follows: 11% to 68% (N=45), 69% to <85% (N=46), and ≥85% (N=46). Compared with control, mean improvement in 6-minute walk was significantly greater in each SET tertile: mean (95% CI) for tertile 1, 27.9 m (1.3-54.4 m; P=0.04), tertile 2, 38.2 m (12.2-64.2 m; P=0.001), and tertile 3, 56.9 m (29.9-83.8 m; P<0.0001). Among participants randomized to SET, greater SET attendance was associated with greater improvement in 6-minute walk distance (overall P for trend=0.025). Compared with control, improvement in maximal treadmill walking time was greater in each SET attendance tertile: tertile 1 (3.3 minutes [95% CI, 1.7-4.8 minutes]; P<0.0001), tertile 2 (3.8 minutes [95% CI, 2.3-5.3 minutes]; P<0.0001), and tertile 3 (5.4 minutes [95% CI, 3.9-7.0 minutes]; P:<0.0001). Among participants randomized to SET, greater attendance at SET was not significantly associated with greater improvement in maximal treadmill walking time (overall P for trend=0.064). Conclusions Among people with PAD randomized to SET, better attendance at exercise sessions was associated with significantly greater 6-minute walk improvement. Among all participants with PAD, even relatively low SET attendance was associated with significantly greater improvement in walking performance, compared with a control group who did not exercise. Registration URL: https://clinicaltrials.gov/ct2/show/NCT01408901. URL: https://clinicaltrials.gov/ct2/show/NCT00106327.

A Multicenter, Investigator-Blinded, Randomized Controlled Trial to Assess the Efficacy of Calf Neuromuscular Electrical Stimulation Program on Walking Performance in Peripheral Artery Disease: The ELECTRO-PAD Study Protocol

This paper describes a currently on-going multicenter, randomized controlled trial designed to assess the efficacy of calf neuromuscular electrical stimulation (NMES) on changes in maximal walking distance in people with lower extremity peripheral artery disease (PAD), compared with a non-intervention control-group. This study (NCT03795103) encompasses five participating centers in France. PAD participants with a predominant claudication at the calf level and a maximal treadmill walking distance ≤300 m are randomized into one of the two groups: NMES group or Control group. The NMES program consists of a 12-week program of electrical stimulations at the calf-muscle level. The primary outcome of the study is the change in maximal treadmill walking distance at 12 weeks. Main secondary outcomes include changes in the pain-free treadmill walking distance; 6 min total walking distance; global positioning system (GPS)-measured outdoor walking capacity; daily physical activity level by accelerometry; self-reported walking impairment; self-reported quality of life; ankle-brachial index; and skin microvascular function, both at the forearm and calf levels. Recruitment started in September 2019 and data collection is expected to end in November 2022.

Network Meta-Analysis of Trials Testing If Home Exercise Programs Informed by Wearables Measuring Activity Improve Peripheral Artery Disease Related Walking Impairment

Background: This study aimed to investigate whether home exercise programs informed by wearable activity monitors improved walking ability of patients with peripheral artery disease (PAD). Methods: A systematic literature search was performed to identify randomised controlled trials (RCT) testing home exercise that were or were not informed by wearable activity monitors. The primary outcome was the change in walking distance measured by a six-minute walking test or treadmill test over the course of the trial. Network meta-analysis (NMA) was performed using the gemtc R statistical package. The risk of bias was assessed using Cochrane tool for assessing risk of bias in RCTs (RoB 2.0). Results: A total of 14 RCTs involving 1544 participants were included. Nine trials used wearable activity monitors to inform the home exercise program tested, while five trials did not use wearable activity monitors to inform the home exercise program tested. Overall quality assessment showed 12 trials to be at low risk of bias and two trials at high risk of bias. Home exercise programs informed by wearable activity monitors significantly improved walking distance compared to non-exercise controls (Mean difference, MD: 32.8 m [95% credible interval, CrI: 6.1, 71.0]) but not compared to home exercise programs not informed by wearable activity monitors (MD: 4.7 m [95% CrI: -38.5, 55.4]). Conclusions: Home exercise informed by wearable activity monitors improve walking ability of patients with PAD. It is, however, unclear if activity monitoring informed exercise programs are more effective than exercise programs not using activity monitors.

Supervised exercise training in patients with lower extremity peripheral artery disease

Summary: The optimal first line management of patients with symptomatic chronic lower extremity peripheral artery disease (PAD) includes secondary prevention of cardiovascular risk factors, pharmacological treatment, and supervised exercise therapy (SET). SET programs have shown to be effective in improving walking performance, functional performance, and quality of life. However, despite a large body of evidence, and despite national and international guidelines recommending SET as first line therapy, SET remains largely underused in patients with chronic PAD. This position paper aims to describe how SET is perceived, its accessibility and structure through Europe. An anonymous web-based survey was used. It comprised 21 questions developed in conjunction with an angiologist and a clinical exercise physiologist specialist in vascular rehabilitation. We had 131 responders from 17 countries. For patients with PAD, SET programs exist only in 59% of European countries. SET reimbursement is available in 41% of countries. SET programs showed to be heterogeneous across countries. Thirty-four percent of the SET programs are PAD-dedicated, while 23% are part of a cardiac rehabilitation program. In addition, among existing SET programs, 65% are dedicated to symptomatic patients with PAD only, 9% to both asymptomatic and symptomatic, 8% to post-revascularized patients only, and 1% to asymptomatic patients with PAD only. Finally, 17% reported not knowing which patients are eligible for enrolment in a SET program. Duration, frequency, and modality of SET also varied from country to country. Overall, these data indicate that a large variability of SET availability and characteristics exists across Europe. Therefore, there is an urgent need to provide detailed guidance to deliver optimal exercise therapeutic care in patients with PAD.

Effects of home-based leg heat therapy on walking performance in patients with symptomatic peripheral artery disease: a pilot randomized trial

Few noninvasive therapies currently exist to improve functional capacity in people with lower extremity peripheral artery disease (PAD). The goal of the present study was to test the hypothesis that unsupervised, home-based leg heat therapy (HT) using water-circulating trousers perfused with warm water would improve walking performance in patients with PAD. Patients with symptomatic PAD were randomized into either leg HT (n = 18) or a sham treatment (n = 16). Patients were provided with water-circulating trousers and a portable pump and were asked to apply the therapy daily (7 days/wk, 90 min/session) for 8 wk. The primary study outcome was the change from baseline in 6-min walk distance at 8-wk follow-up. Secondary outcomes included the claudication onset-time, peak walking time, peak pulmonary oxygen consumption and peak blood pressure during a graded treadmill test, resting blood pressure, the ankle-brachial index, postocclusive reactive hyperemia in the calf, cutaneous microvascular reactivity, and perceived quality of life. Of the 34 participants randomized, 29 completed the 8-wk follow-up. The change in 6-min walk distance at the 8-wk follow-up was significantly higher (P = 0.029) in the group exposed to HT than in the sham-treated group (Sham: median: -0.9; 25%, 75% percentiles: -5.8, 14.3; HT: median: 21.3; 25%, 75% percentiles: 10.1, 42.4, P = 0.029). There were no significant differences in secondary outcomes between the HT and sham group at 8-wk follow-up. The results of this pilot study indicate that unsupervised, home-based leg HT is safe, well-tolerated, and elicits a clinically meaningful improvement in walking tolerance in patients with symptomatic PAD.NEW & NOTEWORTHY This is the first sham-controlled trial to examine the effects of home-based leg heat therapy (HT) on walking performance in patients with peripheral artery disease (PAD). We demonstrate that unsupervised HT using water-circulating trousers is safe, well-tolerated, and elicits meaningful changes in walking ability in patients with symptomatic PAD. This home-based treatment option is practical, painless, and may be a feasible adjunctive therapy to counteract the decline in lower extremity physical function in patients with PAD.

Inequity in exercise-based interventions for adults with intermittent claudication due to peripheral arterial disease: a systematic review

PURPOSE

To determine the equity in access to trials of exercise interventions for adults with intermittent claudication due to peripheral arterial disease.

METHODS

Systematic electronic database searches of MEDLINE, Embase, CINAHL, Cochrane Central Register of Controlled Clinical Trials, PEDRO, Opengrey, ISRCTN and ClinincalTrials.gov for randomised controlled trials of exercise interventions for adults with intermittent claudication were conducted. Data extraction was informed by Cochrane's PROGRESS-Plus framework.

RESULTS

Searches identified 6412 records. Following the screening of 262 full texts, 49 trials including 3695 participants were included. All trials excluded potential participants on at least one equity factor. This comprised place of residence, language, sex, personal characteristics (e.g., age and disability), features of relationships (e.g., familial risk factors) and time-dependent factors, (e.g., time since revascularisation). Overall, 1839 of 7567 potential participants (24.3%) were excluded based on equity factors. Disability was the most frequently reported factor for exclusions.

CONCLUSION

Trialists endeavour to enrol a representative sample in exercise trials whilst preserving the safety profile of the intervention. This review highlights that these efforts can inadvertently lead to inequities in access as all trials excluded potential participants on at least one equity factor. Future exercise trials should optimise participation to maximise generalisability of findings. PROSPERO registration no. CRD42020189965.Implications for rehabilitationEquity factors influence health opportunities and outcomes.All trials of exercise for people with intermittent claudication excluded adults on at least one equity factor.Disability was the predominant factor for exclusions from trials.Trials should optimise participation to maximise generalisability of results as these findings are used to inform treatment and service design.

Effectiveness of supervised exercise, home-based exercise or walk advice strategies on walking performance and muscle endurance in patients with intermittent claudication (SUNFIT trial)-a randomized clinical trial

BACKGROUND

Supervised exercise is a guideline-recommended treatment in intermittent claudication (IC). Hospital-based supervised exercise-programmes (SEP) are underutilized while home-based structured exerciseprogrammes (HSEP) have attracted interest. The results from HSEP in IC are inconsistent and may confer no benefit over walk advice (WA) and be less effective than SEP.

AIMS

To compare the effectiveness of best medical treatment, including Nordic pole WA alone, or WA + SEP or WA + HSEP for patients with IC.

METHODS

This three-armed, multicentre randomized clinical trial enrolled patients with IC, all patients received best medical treatment including walking poles and the advice of regular Nordic pole walking (WA). For HSEP and SEP, additional exercise programmes were provided. The primarily investigated hypothesis was a non-inferiority analysis of SEP vs HSEP regarding the six-minute walk test (6MWT) maximum distance, with a pre-defined non-inferiority margin of 50 m. Supporting outcomes included muscle endurance tests and the Walking Impairment Questionnaire. Outcomes were assessed at baseline, 3, 6 and 12 months by a blinded evaluator.

RESULTS

Altogether 166 patients (mean age 72 years; 59% males) were randomized. In HSEP were 24% and SEP 26% fully exercise adherent. All three groups improved pain-free walking distance over time, but there were no significant intergroup differences. The intergroup 6MWT difference between SEP and HSEP from 0-12 months was -11.6  m, 95% CI: -36.4 to 13.0  m (i.e., within the pre-specified non-inferiority margin).

CONCLUSION

HSEP was non-inferior to SEP in patients with IC. There were no significant differences observed between the three groups at one year.

CLINICAL TRIAL DATABASE ID

Registration: ClinicialTrials.gov (NCT02341716). Trial registry name: Hospital- and Home-based Supervised Exercise Versus Unsupervised Walk Advice For Patients With InTermittent Claudication (SUNFIT).

Current Management of Peripheral Artery Disease: Focus on Pharmacotherapy

Peripheral artery disease (PAD) is the occlusion or narrowing of the arteries supplying the lower extremities. Peripheral artery disease has been estimated to affect approximately 240 million people worldwide, approximately 70% of whom are within low- or middle-income countries. Due to the ageing population and diabetes epidemic, the prevalence of PAD is rapidly rising. The symptoms of PAD are heterogeneous and thus a high index of suspicion is needed to prevent delays in diagnosis and treatment. Measurement of ankle brachial pressure index or arterial duplex ultrasound are traditionally used to diagnose PAD. Patients with PAD have a high risk of major adverse cardiovascular events. Early diagnosis and implementation of secondary cardiovascular prevention is therefore critical. This includes therapies to reduce low-density lipoprotein cholesterol, such as statins, ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, blood-pressure reducing medications and anti-thrombotic drugs. Treatments to facilitate smoking cessation and control blood sugar if relevant and an exercise programme are also critical in reducing cardiovascular risk. Currently, these treatments are not well implemented. This review summarises the clinical presentation, risk factors and medical management of PAD. Global efforts are needed to reduce the burden from the growing PAD epidemic by implementing best practices and improving outcomes through further research.

A Systematic Review on Smartphone Use for Activity Monitoring During Exercise Therapy in Intermittent Claudication

OBJECTIVE

Supervised exercise therapy (SET) is recommended as first line in the management of intermittent claudication (IC). Its use is often limited by accessibility, compliance and cost. Home-based exercise therapy (HBET) programs emerged as an alternative solution, but have shown inferior results. Employment of structured monitoring with the use of external wearable activity monitors (WAM) has been shown to improve outcomes. Mobile applications can make use of built-in accelerometers of modern smartphones and become an alternative solution for monitoring patients during HBET, potentially providing wider accessibility. This review aims to assess current use of smartphone technology (i.e., mobile apps) for monitoring or tracking patients' activity in exercise therapy for peripheral arterial disease (PAD).

METHODS

The PubMed database was searched from January 2011 to September 2021. Eligible articles had to include a population of patients with PAD, conduct a mobile-health (m-health) exercise intervention and use smartphone technology for monitoring or tracking patients' activity. Randomized control trials (RCTs), prospective studies, and study protocols were included.

RESULTS

A total of seven articles met the selection criteria. These described six different studies and five different mobile applications. Three were fitness apps (FitBit, Nike+ FuelBand and Garmin Connect) that synchronized with commercially available WAMs to provide users with feedback. Two were PAD-specific apps (TrackPAD and Movn) developed specifically to assess patients' activity during exercise therapy. PAD-specific apps also incorporated coaching and educational elements such as weekly goal setting, claudication reminders, messaging, gamification, training advice and PAD education.

CONCLUSION

Current HBET programs use smartphone applications mainly via commercially available fitness apps that synchronize with WAM devices to register and access data. PAD-specific apps are scarce but show promising features that can be used to monitor, train, coach, and educate patients during HBET programs. Larger studies combining these elements into HBET programs should provide future direction.

Decision Aids for Determining Facility Versus Non-Facility-Based Exercise in Those with Symptomatic Peripheral Artery Disease

Purpose of Review

This paper sought to provide rationale for determining when a patient with symptomatic peripheral artery disease (PAD) might be referred for home-based versus facility-based exercise therapy.

Recent Findings

Multiple randomized controlled studies have embedded supervised, structured exercise therapy as a class IA recommended therapy for those with symptomatic PAD. More recently, there is interest in non-facility-based exercise training as an alternative. The current literature is mixed on the effectiveness of non-facility-based training and is influenced by the amount of contact with clinical staff providing some supervision (e.g., occasional facility-based exercise or coaching phone calls), and the intensity (e.g., performed intermittently by inducing pain or continually and not inducing pain) and frequency (e.g., 12-week common supervised exercise program or those longer than 24 weeks) of exercise. Certainly, the data suggests non-facility-based exercise, while possibly improving walking performance, is inferior to facility-based supervised exercise training. Comprehensive data is lacking on utilization of supervised exercise therapy in those with symptomatic PAD, but is likely <2% of those eligible who participate. This suggests a possible important role for alternatives including non-facility-based (e.g., home, fitness center).

Summary

Exercise training in the supervised, facility-based setting appears to be greatly underutilized. Non-facility-based exercise may help to overcome some of the most common barriers to participating in facility-based exercise including those related to motivation, transportation, and proximity. However, facility-based training is considered the gold standard so decisions about allowing a patient to exercise train at home must take into account issues including disease severity, patient motivation and available exercise resources, mobility and balance, cognitive function, and other medical concerns (e.g., symptomatic coronary artery disease or heart failure).

Assessing Wear Time and Perceptions of Wearing an Ankle Foot Orthosis in Patients with Peripheral Artery Disease

BACKGROUND

Peripheral artery disease (PAD) is a cardiovascular disease that effects patients' walking ability. An ankle foot orthosis (AFO) may improve patients' walking distances. Little research has explored if patients wear a prescribed AFO and their perceptions of wearing the device.

OBJECTIVE

To assess wear time of an AFO and explore perceptions of wearing the device in patients with peripheral artery disease.

DESIGN

Convergent mixed methods.

SETTING

The study was administered through a tertiary care medical center and the research subjects used the device in an outpatient setting in and out of their homes during their regular activities.

PARTICIPANTS

Patients were referred to the study by their vascular surgeon. Thirty-six patients, all older adult males, were enrolled in this study. Fourteen patients completed the study and 11 supplied sufficient accelerometer data.

INTERVENTIONS

An AFO was worn for 3 months. An accelerometer was placed on the AFO for 7 days at midpoint (1.5 months) and endpoint of the intervention (3 months) to assess wear time. Semi-structured interviews explored patients' perceptions of wearing the AFO.

MAIN OUTCOME MEASURE

The primary outcome measure was wear time measured objectively via accelerometer and subjectively via interview.

RESULTS

Patients (n = 14) wore the AFO around 8 hours/day. Most patients felt they wore the AFO a majority of the time. Patients reported barriers such as challenges wearing the AFO during daily household activities (using stairs, being on uneven terrain), discomfort, clothing or footwear issues, and driving challenges. Positive impacts of wearing the AFO were also reported, primarily the ability to walk further.

CONCLUSIONS

An AFO may be an acceptable therapeutic intervention to improve perceived walking performance in older adult males with PAD. Addressing patients' perceptions of the AFO and barriers to wear are essential to increasing the positive impact the device has on patients' ambulatory activity. This article is protected by copyright. All rights reserved.

Improvement in walking impairment following surgical and endovascular revascularization: Insights from VOYAGER PAD

BACKGROUND

Peripheral artery disease (PAD) affects 200 million people worldwide and is associated with impaired quality of life, increased morbidity, and mortality. Supervised exercise therapy (SET) and lower-extremity revascularization (LER) are both proven strategies to improve patient symptoms. Short and long-term functional outcomes after LER for symptomatic PAD in a large, international cohort have not previously been described.

METHODS

The VOYAGER PAD trial (ClinicalTrials.gov identifier: NCT02504216) enrolled subjects after LER for symptomatic PAD (Rutherford category 2-6). Participants completed the Walking Impairment Questionnaire (WIQ) at baseline, 1, 3 and 6 months, and every 6 months thereafter. The primary outcome analysis was degree of difficulty walking two blocks at each of the aforementioned time points. Difficulty walking three blocks and climbing one flight of stairs at these time points was also analyzed. Data about supervised and home exercise therapy before or after revascularization were not collected in the VOYAGER PAD trial.

RESULTS

Of the 5614 VOYAGER PAD participants completing the WIQ at baseline, three-quarters presented with claudication and one-quarter with critical limb ischemia. Of these, the majority (62% with claudication and 74% with CLI) reported inability or much difficulty walking two blocks prior to LER. Walking improved after LER regardless of revascularization strategy, but one-fifth with claudication and one-third with CLI reported continued inability or much difficulty walking two blocks 1 month after LER. Participants who reported improved walking ability 1 month after LER experienced a durable functional result out to 3 years. Although the proportion of participants reporting significant baseline difficulty climbing one flight of stairs or walking three blocks differed, the trend in immediate and sustained improvement after LER was similar to that observed for walking two blocks.

CONCLUSION

In this large, international cohort undergoing LER for symptomatic PAD, nearly two-thirds reported inability or much difficulty walking two blocks at baseline. Although many participants reported improved walking ability after LER, a substantial proportion remained severely disabled. These observations may help motivate providers, patients, and medical systems to improve awareness and engagement in SET referral after LER.

The effect of 12-week treatment with intermittent negative pressure on blood flow velocity and flowmotion, measured with a novel Doppler device (earlybird). Secondary outcomes from a randomized sham-controlled trial in patients with peripheral arterial disease

OBJECTIVES

Treatment with intermittent negative pressure (INP) is proposed as an adjunct to standard care in patients with peripheral arterial disease (PAD). The aims of this study were to evaluate the applicability of a novel ultrasound Doppler device (earlybird) to assess blood flow characteristics in patients with PAD during a treatment session with INP, and whether certain flow-properties could determine whom could benefit INP treatment.

METHODS

Secondary outcomes of data from a randomized sham-controlled trial were explored. Patients were randomized to 12 weeks of treatment with 40 mmHg or 10 mmHg INP, for one hour twice daily. Earlybird blood flow velocity recordings were made before and after the 12-week treatment-period and consists of a 5-minute recording in rest, 3-minute during INP treatment and 5-minute recording after ended INP test-treatment. Mean blood flow velocity (v_mean), relative changes in flow and frequency spectrum by Fourier-transform of the respective bandwidths of endothelial, sympathetic, and myogenic functions, were analyzed for the different series of blood flow measurements.

RESULTS

In total, 62 patients were eligible for analysis, where 32 patients were treated with 40 mmHg INP. The acquired recordings were of good quality and was used for descriptive analyses of flow characteristics. An immediate increase in v_mean during the negative pressure periods of the INP test-treatment was observed in the 40 mmHg INP treatment group at both pre- and post-test. There was a significant difference between the treatment groups, with a difference between the medians of 13.7 (p < 0.001) at pretest and 10.7 (p < 0.001) at posttest. This finding was confirmed with spectrum analysis by Fourier-transform of the bandwidth corresponding to INP treatment. The change in amplitude corresponding to myogenic function after 12 weeks of treatment, was significantly different in favor of the 40 mmHg INP treatment group. We were not able to detect specific flow characteristics indicating whom would benefit INP-treatment.

CONCLUSIONS

Earlybird is an applicable tool for assessing blood flow velocity in patients with PAD. Analysis of the flow velocity recordings shows that INP induce an immediate increase in blood flow velocities during INP. The positive effects of INP may be attributed to recruitment of arterioles, and thereby increasing blood flow. In these analyses no flow characteristics was determined which could predict whom would benefit INP-treatment.

Society for Vascular Surgery Appropriate Use Criteria for Management of Intermittent Claudication

The Society for Vascular Surgery (SVS) Appropriate Use Criteria (AUC) for Management of Intermittent Claudication were created using the RAND appropriateness method (RAM) which is a validated and standardized methodology that combines best-available evidence from medical literature with expert opinion, using a modified-Delphi process. These criteria serve as a framework upon which individualized patient and clinician shared decision-making can grow. These criteria are not absolute. AUC should not be interpreted as a requirement to administer treatments rated as appropriate (benefit outweighs risk). Nor should AUC be interpreted as a prohibition on treatments rated as inappropriate (risk outweighs benefit). There will be clinical situations in which moderating factors, not included in these AUC, will shift the appropriateness level of a treatment for an individual patient. Proper implementation of AUC calls for a description of those moderating patient factors. For scenarios with an indeterminate rating, clinician judgement combined with best available evidence should determine treatment strategy. Importantly, these are scenarios in need of mechanisms to track treatment decisions and outcomes. AUC should be revisited on a periodic basis to ensure that these criteria remain relevant. The panelists rated 2280 unique scenarios for the treatment of intermittent claudication (IC) in the aortoiliac, common femoral and femoropopliteal segment in Round 2 rating. Of these, only 9 (0.4%) had disagreement according to the IPRAS formula, indicating an exceptionally high degree of consensus among the panelists. [Note, post-hoc, the term, "inappropriate," was replaced with the term "R>B" (risk outweighs benefit). The term "appropriate" was also replaced with "B>R" (benefit outweighs risk)]. The key principles for the management of intermittent claudication reflected within these AUC are: (1) Exercise therapy is a preferred initial management strategy for all patients with IC. (2) For patients who have not completed exercise therapy, invasive therapy may provide net benefit in selected patients with IC who are non-smokers, are taking optimal medical therapy, are considered low physiologic and technical risk, and who are experiencing severe lifestyle limitation and/or short walking distance. (3) Considering the long-term durability of currently available technology, invasive interventions for femoropopliteal disease should be reserved for patients with severe lifestyle limitation and short walking distance. (4) In the common femoral segment, open common femoral endarterectomy provides greater net benefit than endovascular intervention for the treatment of IC. (5) In the infrapopliteal segment, invasive intervention for the treatment of intermittent claudication is of unclear benefit and may be harmful.

WalkingPad protocol: a randomized clinical trial of behavioral and motivational intervention added to smartphone-enabled supervised home-based exercise in patients with peripheral arterial disease and intermittent claudication

Background

Physical exercise is a first-line treatment for peripheral arterial disease (PAD) and intermittent claudication (IC) reducing pain and increasing the distances walked. Home-based exercise therapy (HBET) has the advantage of reaching a higher number of patients and increasing adherence to physical exercise as it is performed in the patient’s residential area and does not have the time, cost, and access restrictions of supervised exercise therapy (SET) implemented in a clinical setting. Even so, rates of adherence to physical exercise are relatively low, and therefore, m-health tools are promising in increasing motivation to behavior change and adherence to physical exercise. A built-in virtual assistant is a patient-focused tool available in a mobile interface, providing a variety of functions including health education, motivation, and implementation of behavior change techniques.

Methods

This is a single-center, prospective, three-arm, single-blind, randomized, controlled, superior clinical trial with stratified and blocked random allocation. Three hundred participants with PAD and IC will be recruited from an Angiology and Vascular Surgery Department, Centro Hospitalar Universitário Porto (CHUPorto), Porto, Portugal. All patients will receive the same medical care recommended by  current guidelines. Participants in all three groups will receive a personalized prescription for an HBET program and a behavioral change and motivational intervention. Participants in experimental groups 1 and 2 will receive a smartphone with the WalkingPad app to monitor exercise sessions. Experimental group 2 WalkingPad app will have a built-in virtual assistant that will promote behavioral change and provide motivational support. Participants allocated to the active control group will not receive the m-health tool, but a practice diary to encourage monitoring. The  program will last for 6 months with three evaluation moments (baseline, 3, and 6 months). The primary outcome will be the change in distances walked (maximal and pain-free) from baseline to 3 and 6 months. Secondary outcomes will be changes in quality of life, patients’ perception of resistance, and walking speed.

Discussion

This study will allow measuring the effectiveness of an m-health tool in increasing motivation for behavior change and adherence to an HBET program in patients with PAD. The superiority of experimental group 2 in the primary and secondary outcomes will indicate that the virtual assistant is effective for motivating behavioral change and encouraging the practice and adherence to physical exercise. The use of m-health tools and virtual health assistants can potentially fill a gap in the access and quality of health services and information, reducing the burden on the health system and promoting self-management and self-care in chronic illness.

Trial registration

ClinicalTrials.govNCT04749732. Registered on 10 February 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06279-9.