Preliminary evidence that low ankle-brachial index is associated with reduced bilateral hip extensor strength and functional mobility in peripheral arterial disease

ObjectivePeripheral arterial disease (PAD) has been associated with skeletal muscle pathology, including atrophy of the affected muscles. In addition, oxidative metabolism is impaired, muscle function is reduced, and gait and mobility are restricted. We hypothesized that greater severity of symptomatic PAD would be associated with lower levels of muscle mass, strength, and endurance, and that these musculoskeletal abnormalities in turn would impair functional performance and walking ability in patients with PAD.MethodsWe assessed 22 persons with intermittent claudication from PAD in this cross-sectional pilot study. Outcome assessments included initial claudication distance and absolute claudication distance via treadmill protocols and outcomes from the 6-minute walk (6MW). Secondary outcomes included one repetition maximum strength/endurance testing of hip extensors, hip abductors, quadriceps, hamstrings, plantar flexors, pectoral, and upper back muscle groups, as well as performance-based tests of function. Univariate and stepwise multiple regression models were constructed to evaluate relationships and are presented.ResultsTwenty-two participants (63.6% male; mean [standard deviation] age, 73.6 [8.2] years; range, 55-85 years) were studied. Mean (standard deviation) resting ankle-brachial index (ABI) was 0.54 ([0.13]; range, 0.28-0.82), and participants ranged from having mild claudication to rest pain. Lower resting ABI was significantly associated with reduced bilateral hip extensor strength (r = 0.54; P = .007) and reduced whole body strength (r = 0.32; P = .05). In addition, lower ABI was associated with a shorter distance to first stop during the 6MW (r = 0.38; P = .05) and poorer single leg balance (r = 0.44; P = .03). Reduced bilateral hip extensor strength was also significantly associated with functional outcomes, including reduced 6MW distance to first stop (r = 0.74; P = .001), reduced 6MW distance (r = 0.75; P < .001), and reduced total short physical performance battery score (worse function; r = 0.75; P = .003).ConclusionsOur results suggest the existence of a causal pathway from a reduction in ABI to muscle atrophy and weakness, to whole body disability represented by claudication outcomes and performance-based tests of functional mobility in an older cohort with symptomatic PAD. Longitudinal outcomes from this study and future trials are required to investigate the effects of an anabolic intervention targeting the muscles involved in mobility and activities of daily living and whether an increase in muscle strength will improve symptoms of claudication and lead to improvements in other functional outcomes in patients with PAD

Exercise training for intermittent claudication:a narrative review and summary of guidelines for practitioners

Peripheral artery disease (PAD) is caused by atherosclerotic narrowing of the arteries supplying the lower limbs often resulting in intermittent claudication, evident as pain or cramping while walking. Supervised exercise training elicits clinically meaningful benefits in walking ability and quality of life. Walking is the modality of exercise with the strongest evidence and is recommended in several national and international guidelines. Alternate forms of exercise such as upper- or lower-body cycling may be used, if required by certain patients, although there is less evidence for these types of programmes. The evidence for progressive resistance training is growing and patients can also engage in strength-based training alongside a walking programme. For those unable to attend a supervised class (strongest evidence), home-based or ‘self-facilitated’ exercise programmes are known to improve walking distance when compared to simple advice. All exercise programmes, independent of the mode of delivery, should be progressive and individually prescribed where possible, considering disease severity, comorbidities and initial exercise capacity. All patients should aim to accumulate at least 30 min of aerobic activity, at least three times a week, for at least 3 months, ideally in the form of walking exercise to near-maximal claudication pain

Resistance training as a treatment for older persons with peripheral artery disease: A systematic review and meta-analysis

Objective: Resistance training (RT) improves walking ability in persons with peripheral artery disease. We conducted a meta-analysis of randomised controlled trials (RCTs) investigating the effect of RT on peripheral artery disease (as measured by walking ability). Design: We included RCTs that investigated the effect of RT on treadmill and/or 6 min walk (6-MWT) distances. RT intensity was assessed according to the American College of Sports Medicine guidelines by 1 repetition maximum or rating of perceived exertion. Standardised mean (SMD) and mean differences (MD) were calculated using a random-effects inverse variance model. Heterogeneity and bias were assessed using RevMan V.5.3. Meta-regression and meta-analysis of variance were performed as moderator analyses. Data sources: Databases (Medline, Embase, Web of Science, Cinahl and Google Scholar) were searched until July 2018. Results: Fifteen trials isolated RT; 7 trials compared RT with aerobic exercise. We analysed 826 patients (n=363 completing RT), with a mean age of 67.1±3.8 years. Training ranged from low-high intensity, 2-7 times per week for 17±7 weeks, with a mix of upper, lower or whole body training. Overall RT significantly improved constant load treadmill claudication onset (COD) (SMD 0.66 [0.40, 0.93],

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

Background: Physical activity is recommended for people with peripheral arterial disease (PAD), and can improve walking capacity and quality of life; and reduce pain, requirement for surgery and cardiovascular events. This trial will assess the efficacy of a brief behavioral counselling intervention delivered by allied health professionals to improve physical activity in people with PAD. Methods: This is a multi-center randomised controlled trial in four cities across Australia. Participants (N = 200) will be recruited from specialist vascular clinics, general practitioners and research databases and randomised to either the control or intervention group. Both groups will receive usual medical care, a written PAD management information sheet including advice to walk, and four individualised contacts from a protocol-trained allied health professional over 3 months (weeks 1, 2, 6, 12). The control group will receive four 15-min telephone calls with general discussion about PAD symptoms and health and wellbeing. The intervention group will receive behavioral counselling via two 1-h face-to-face sessions and two 15-min telephone calls. The counselling is based on the 5A framework and will promote interval walking for 3 × 40 min/week. Assessments will be conducted at baseline, and 4, 12 and 24 months by staff blinded to participant allocation.Objectively assessed outcomes include physical activity (primary), sedentary behavior, lower limb body function, walking capacity, cardiorespiratory fitness, event-based claudication index, vascular interventions, clinical events, cardiovascular function, circulating markers, and anthropometric measures. Self-reported outcomes include physical activity and sedentary behavior, walking ability, pain severity, and health-related quality of life. Data will be analysed using an intention-to-treat approach. An economic evaluation will assess whether embedding the intervention into routine care would likely be value for money. A cost-effectiveness analysis will estimate change in cost per change in activity indicators due to the intervention, and a cost-utility analysis will assess change in cost per quality-adjusted life year. A full uncertainty analysis will be undertaken, including a value of information analysis, to evaluate the economic case for further research. Discussion: This trial will evaluate the efficacy and cost-effectiveness of a brief behavioral counselling intervention for a common cardiovascular disease with significant burden. Trial registration: ACTRN 12614000592640 Australian New Zealand Clinical Trials Registry. Registration Date 4 June 2014

Exercise for improving management of peripheral arterial disease

Peripheral arterial disease significantly impacts on the independence, quality of life and health of older adults. Lifestyle management provides an important course of action with exercise being a key contributor to improving long-term patient health. Incorporation of various exercise types and intensities with guidance from qualified exercise practitioners and clinicians will contribute to effective and successful patient management

Authors' Reply to Li et al.: "Alternative Statistical Analysis Shows Exercise Training-Induced Improvements in Peak VO₂ are Clinically Significant"

We thank Dr. Li et al. for their commentary on our recently published meta-analysis in Sports Medicine. While there is no doubt that there is an argument for the use of a random-effects model in the presence of significant heterogeneity, such a model can introduce inherent problems of its own

Exercise Training for Management of Peripheral Arterial Disease: A Systematic Review and Meta-Analysis

Background: Peripheral arterial disease (PAD), a chronic condition with debilitating clinical sequelae, leads to reduced walking activity and increased mortality risk. Objective: We sought to quantify expected benefits elicited via exercise training in people with PAD and aimed to clarify which prescriptions were optimal. Data sources: We conducted a systematic search (Pub- Med, CINAHL, Cochrane controlled trials registry; 1966-31 July 2013). Study selection: We included randomized controlled trials (RCTs) of exercise training versus usual medical care in persons with PAD. Studies were assessed by two reviewers, 41 of 57 (72 %) of RCTs met selection criteria. Data extraction and synthesis: Data extraction sheets were used to record data and two reviewers cross-checked data. Included study authors were asked for missing data. Main outcomes and measures: Primary outcome: change in aerobic capacity (peak VO₂). Secondary outcomes: anklebrachial index (ABI), flow-mediated dilatation, 6-minute walk claudication distances (initial and absolute) and graded treadmill (initial and absolute) distances. The primary hypothesis was that peak VO₂ would increase with exercise training. Using sub-analyses, we also aimed to clarify what types of exercise prescription would provide patients with most benefit; hypotheses were developed a priori

Exercise Training for Management of Peripheral Arterial Disease: a Systematic Review and Meta-Analysis

Objective: To quantify expected benefits of exercise training in people with peripheral arterial disease (PAD). Hypothesis: Walking as a training modality and training to mild pain were optimal for improving peak VO₂ and symptoms. Methods: We conducted a systematic search (PubMed, CINAHL, Cochrane controlled trials registry; 1966-May 31, 2014). We included randomized controlled trials (RCT's) of exercise training versus usual medical care in persons with PAD, 42 of 60 (70%) RCT's met selection criteria. ... Conclusions and Relevance: Various modes of exercise improve cardio-respiratory fitness, pain free and total flat ground walking distances and graded treadmill performance in PAD. Alternative modes of exercise are understudied in terms of quality of life, however walking to some level of claudication pain improves WIQ speed, distance and stair climbing scores in PAD as well as SF-36 physical component score

Exercise training for health-related quality of life in peripheral artery disease: A systematic review and meta-analysis

We sought to quantify whether health-related quality of life (HRQoL) is improved through exercise training in people with peripheral artery disease (PAD) and to clarify which prescriptions were optimal for improving HRQoL when compared to usual care. We conducted a systematic search (PubMed, CINAHL, Cochrane Central Register of Controlled Trials; 1966 - 31 August 2014). We only included randomized controlled trials (RCTs) of exercise training versus usual medical care in persons with PAD that included the Walking Impairment Questionnaire (WIQ) and Short-Form Health Survey component summary scores as outcomes. Of 15 RCTs, 1257 participants were studied: 543 participated in supervised exercise, with only 61 undertaking resistance training and 316 unsupervised exercise. When compared to controls, participants who completed any form of exercise training significantly improved their WIQ speed [mean difference (MD) 9.60 (95% CI 6.98 to 12.23,