Ryan J. Mays

Assessment of functional status and quality of life in claudication.

BACKGROUND Treadmill walking is commonly used to evaluate walking impairment and efficacy of treatment for intermittent claudication (IC) in clinical and research settings. Although this is an important measure, it does not provide information about how patients perceive the effects of their treatments on more global measures of health-related quality of life (HRQOL). METHODS PubMed/Medline was searched to find publications about the most commonly used questionnaires to assess functional status and/or general and disease-specific HRQOL in patients with peripheral artery disease (PAD) who experience IC. Inclusion criteria for questionnaires were based on existence of a body of literature in symptomatic PAD. RESULTS Six general questionnaires and seven disease-specific questionnaires are included, with details about the number of domains covered and how each tool is scored. The Medical Outcomes Study Short Form 36-item questionnaire and Walking Impairment Questionnaire are currently the most used general and disease-specific questionnaires at baseline and after treatment for IC, respectively. CONCLUSIONS The use of tools that assess functional status and HRQOL has importance in both the clinical and research areas to assess treatment efficacy from the patients perspective. Therefore, assessing HRQOL in addition to treadmill-measured walking ability provides insight as to the effects of treatments on patient outcomes and may help guide therapy.

Community walking programs for treatment of peripheral artery disease.

BACKGROUND Supervised walking programs offered at medical facilities for patients with peripheral artery disease (PAD) and intermittent claudication (IC), although effective, are often not used due to barriers, including lack of reimbursement and the need to travel to specialized locations for the training intervention. Walking programs for PAD patients that occur in community settings, such as those outside of supervised settings, may be a viable treatment option because they are convenient and potentially bypass the need for supervised walking. This review evaluated the various methods and outcomes of community walking programs for PAD. METHODS A literature review using appropriate search terms was conducted within PubMed/MEDLINE and the Cochrane databases to identify studies in the English language that used community walking programs to treat PAD patients with IC. Search results were reviewed, and relevant articles were identified that form the basis of this review. The primary outcome was peak walking performance on the treadmill. RESULTS Ten randomized controlled trials examining peak walking outcomes in 558 PAD patients demonstrated that supervised exercise programs were more effective than community walking studies that consisted of general recommendations for patients with IC to walk at home. Recent community trials that incorporated more advice and feedback for PAD patients in general resulted in similar outcomes, with no differences in peak walking time compared with supervised walking exercise groups. CONCLUSIONS Unstructured recommendations for patients with symptomatic PAD to exercise in the community are not efficacious. Community walking programs with more feedback and monitoring offer improvements in walking performance for patients with claudication and may bypass some obstacles associated with facility-based exercise programs.

A comparison of practical assessment methods to determine treadmill, cycle, and elliptical ergometer VO2 peak.

Mays, RJ, Boér, NF, Mealey, LM, Kim, KH, and Goss, FL. A comparison of practical assessment methods to determine treadmill, cycle, and elliptical ergometer &OV0312;O2peak. J Strength Cond Res 24(5): 1325-1331, 2010-This investigation compared estimated and predicted peak oxygen consumption (&OV0312;O2peak) and maximal heart rate (HRmax) among the treadmill, cycle ergometer, and elliptical ergometer. Seventeen women (mean ± SE: 21.9 ± 0.3 y) exercised to exhaustion on all modalities. American College of Sports Medicine metabolic equations were used to estimate &OV0312;O2peak. Digital displays on the elliptical ergometer were used to estimate &OV0312;O2peak. Two individual linear regression methods were used to predict &OV0312;O2peak: (a) 2 steady state heart rate (HR) responses up to 85% of age-predicted HRmax and (b) multiple steady state/nonsteady state HR responses up to 85% of age-predicted HRmax. Estimated &OV0312;O2peak for the treadmill (46.3 ± 1.3 ml·kg−1·min−1) and the elliptical ergometer (44.4 ± 1.0 ml·kg−1·min−1) did not differ. The cycle ergometer estimated &OV0312;O2peak (36.5 ± 1.0 ml·kg−1·min−1) was lower (p < 0.001) than the estimated &OV0312;O2peak values for the treadmill and elliptical ergometer. Elliptical ergometer &OV0312;O2peak predicted from steady-state (51.4 ± .8 ml·kg−1·min−1) and steady-state/nonsteady-state (50.3 ± 2.0 ml·kg−1·min−1) models were higher than estimated elliptical ergometer &OV0312;O2peak, p < 0.01. HRmax, and estimates of &OV0312;O2peak were similar between the treadmill and elliptical ergometer; thus, crossmodal exercise prescriptions may be generated. The use of digital display estimates of submaximal oxygen uptake for the elliptical ergometer may not be an accurate method for predicting &OV0312;O2peak. Health-fitness professionals should use caution when utilizing submaximal elliptical ergometer digital display estimates to predict &OV0312;O2peak.

Exercise Therapy for Claudication: Latest Advances

Opinion statementPeripheral artery disease (PAD) creates a significant national and international healthcare burden. A first line treatment for PAD is supervised walking exercise in hospitals and clinics. Specifically, supervised walking exercise seeks to improve the classic symptom associated with PAD, intermittent claudication (IC), which is characterized by cramping, aching, and pain of the muscles in the lower extremities during walking. While effective, supervised walking exercise is often not prescribed or utilized due to a number of treatment barriers such as lack of transportation to clinical centers and lack of insurance reimbursement. Walking exercise in community settings is an option that has gained attention due to the limitations of supervised walking exercise, as community walking is generally more convenient in terms of a patient’s schedule and may circumvent potential barriers such as treatment cost and transportation difficulties. However, more research is needed to improve the effectiveness of community-based walking programs since far less is known about the optimal structure of such programs. Other exercise therapy options are becoming available for PAD patients in addition to walking exercise. These modalities include but are not limited to leg and arm ergometry, polestriding and resistance training. These exercise therapy options have not to date been as well validated as supervised walking exercise. However, they may potentially be used in the event supervised walking exercise is not feasible or patient preference warrants an alternative exercise strategy.

Community-based walking exercise for peripheral artery disease: An exploratory pilot study

Supervised walking exercise is an effective treatment to improve walking ability of patients with peripheral artery disease (PAD), but few exercise programs in community settings have been effective. The aim of this study was to determine the efficacy of a community-based walking exercise program with training, monitoring and coaching (TMC) components to improve exercise performance and patient-reported outcomes in PAD patients. This was a randomized, controlled trial including PAD patients (n=25) who previously received peripheral endovascular therapy or presented with stable claudication. Patients randomized to the intervention group received a comprehensive community-based walking exercise program with elements of TMC over 14 weeks. Patients in the control group did not receive treatment beyond standard advice to walk. The primary outcome in the intent-to-treat (ITT) analyses was peak walking time (PWT) on a graded treadmill. Secondary outcomes included claudication onset time (COT) and patient-reported outcomes assessed via the Walking Impairment Questionnaire (WIQ). Intervention group patients (n=10) did not significantly improve PWT when compared with the control group patients (n=10) (mean±standard error: +2.1±0.7 versus 0.0±0.7 min, p=0.052). Changes in COT and WIQ scores were greater for intervention patients compared with control patients (COT: +1.6±0.8 versus −0.6±0.7 min, p=0.045; WIQ: +18.3±4.2 versus −4.6±4.2%, p=0.001). This pilot using a walking program with TMC and an ITT analysis did not improve the primary outcome in PAD patients. Other walking performance and patient self-reported outcomes were improved following exercise in community settings. Further study is needed to determine whether this intervention improves outcomes in a trial employing a larger sample size.

Validation of adult OMNI perceived exertion scales for elliptical ergometry

This investigation examined the validity of newly developed Adult OMNI Elliptical Ergometer Ratings of Perceived Exertion Scales. 60 men and women performed a graded exercise test on an elliptical ergometer. Oxygen consumption (VO2), heart rate (HR), and ratings of perceived exertion were recorded at each stage from the Borg 15 Category scale and two different OMNI scales. One scale employed an elliptical ergometer format of the OMNI Picture System of Perceived Exertion. The second scale modified verbal, numerical, and pictorial descriptors at the low end of the response range. Concurrent and construct validity were established by the positive relation between ratings of perceived exertion from each OMNI scale with VO2, HR, and Borg scale ratings of perceived exertion (men, r = .94–.97; women, r = .93–.98). Validity was established for both OMNI scales, indicating either metric can be used to estimate ratings of perceived exertion during partial weight-bearing exercise.

Therapy for Peripheral Artery Disease Gaps in Treating Patients With Claudication

Peripheral artery disease (PAD) is estimated to affect up to 29% of people ≥50 years of age in the United States1 and >200 million people worldwide.2 Diagnosis of PAD is associated with an increased risk of adverse medical events and premature mortality from cardiovascular disease.3,4 The classic symptom of PAD, intermittent claudication (IC), is characterized by exertional leg pain that resolves with rest and is estimated to affect up to 35% of PAD patients ≥50 years of age.5,6 Patients with PAD and IC have impaired walking ability, poor functional outcomes, and a reduced quality of life resulting at least in part from the leg pain experienced.7 Thus, PAD with IC is a significant international healthcare concern with an adverse impact on patients resulting from systemic atherosclerosis and IC symptoms. Few pharmacological therapy options are available to treat PAD symptoms. The most efficacious option currently to improve IC is supervised walking exercise. However, this treatment is not widely available despite strong evidence of its efficacy. In contrast, options that are more readily available to provide symptom relief for IC include invasive treatments such as endovascular therapy and surgical procedures.8 Article see p 939 In this issue of Circulation , Nordanstig and colleagues9 present their results of a comparison of invasive and noninvasive treatments in a prospective, single-center, randomized, clinical trial of patients with stable IC symptoms. The aim of the Invasive Revascularization or Not in Intermittent Claudication (IRONIC) trial was to compare outcomes for PAD patients receiving peripheral revascularization in combination with noninvasive therapy with outcomes in patients who received only noninvasive medical therapy. The noninvasive therapy included the provision of educational materials and medical management of the systemic atherosclerosis, prescription of cilostazol (100 mg twice daily), and general advice …

Patient perspectives on claudication: An opportunity to improve the adoption and adherence of exercise therapy

The impact of exercise on perception of claudication among patients with peripheral artery disease (PAD) is a largely understudied area in vascular medicine. Studies that have examined assessments of leg pain among patients with PAD have highlighted claudication as a barrier to walking exercise.1–3 However, there is not a clear consensus as to why claudication is an impediment to ambulation, specifically when looking through the lens of the PAD patient. If patients are uninformed and believe that leg pain should not be provoked by physical activity, participation in and subsequent compliance with exercise programs will be poor. Thus, assessing how claudication affects a patient, particularly when linked to treatment options and outcomes, may be essential for ensuring optimal uptake and delivery of any PAD exercise program. In this issue of Vascular Medicine, Sharath and colleagues4 provide the results of a pilot study assessing the influence of fear-avoidance beliefs related to physical activity among patients with PAD and claudication (n=20) who were referred to a vascular surgery clinic. The fearavoidance model5 suggests that patients may fear a specific behavior due to negative beliefs and confusion, which ultimately leads to its corollary: avoidance of the behavior. Using this premise, a variety of questionnaires were used to better understand the patients’ physical activity levels and claudication experience. Most notably, patients were asked to complete a modified version of the Fear-Avoidance Beliefs Questionnaire5 to determine if they avoided physical activity because it was perceived to cause harm. Additionally, the Physical Activity Scale for the Elderly6 was used to assess whether fear of exercise was related to patient-reported daily activity. The study findings indicate that the majority of patients were misinformed, and lacked a thorough understanding of the relation between claudication and physical activity. A majority of patients feared exercise was the cause of claudication (n=12/19, 63%), and thought that physical activity would not only make their pain worse (n=18/20, 90%), but would also harm their legs (n=10/18, 56%).4 Conversely, patients with lower fearavoidance belief scores expected greater benefit from exercise, and were less likely to believe they should avoid physical activity due to their leg symptoms. While these results are intuitive, providing objective data of a potential psychological mechanism for why leg pain is a barrier to physical activity among patients with PAD is a key contribution of this study. The authors also conclude that there was no relation of patient-reported physical activity levels and fear-avoidance beliefs. Despite this, linking the etiology of pain from the patient’s perspective and to selfreported levels of physical activity is an important concept to explore.

Understanding sex differences in health status: A frontier in the field of vascular medicine

Although the effects of peripheral artery disease (PAD), including claudication, have been well described in men, much less is known about the effects of PAD on health in women. This is, in part, because for many years PAD was considered a disease that mostly affected men, and only more recently have studies included both women and men in numbers that enable determination of sex differences. Available studies suggest that women with PAD may fare worse than men with regard to health status and quality of life,1,2 but there have not been enough data to enable understanding of the potential causes of these sex differences.3 In this issue of Vascular Medicine, Roumia and colleagues4 provide results and interpretation of an international multicenter registry examining the characteristics of PAD patients (n=1274) with new or worsening PAD symptoms. In the sub-study of the Patient-centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease Investigating Trajectories (PORTRAIT) study, sex differences for disease-specific and overall health status, as measured by the Peripheral Artery Questionnaire (PAQ) and generic health status from the European Quality of Life five dimensions questionnaire, were evaluated cross-sectionally to outline sex differences prior to treatment for PAD. Results indicated that women (n=481) had significantly worse PAQ scores compared to men (n=793) for all domains (p<0.001) except treatment satisfaction (p=0.90). In contrast, men did not have any PAQ domains that were worse than those of women. As observed above, the finding that women have lower health status (which is comprised of elements associated with symptom presentation, functioning, and quality of life) compared to men has been noted in several reports.1,2,5 What is more remarkable is that the PORTRAIT study not only considered physical outcomes, but also a wide array of social, psychological, and economic factors that may have links to lower health status outcomes in women. The outcomes assessed included (but were not limited to) higher rates of depression and financial concerns for women with PAD compared to men, as well as lower rates of married status, possession of health insurance, cohabitation, and health care utilization due to cost. The authors concluded that these factors could not definitively account for the lower health status scores. However, raising these issues opens the door to improved studies of health status by introducing the importance of understanding a broad-based array of determinants of health among patients with vascular disease. How does the current study move the needle toward enhancing outcomes in women with PAD? It highlights the concept that simply treating the classic symptoms of PAD alone may not be the optimal strategy, but rather a comprehensive approach with targeted, sex-specific therapy may be needed.

Research Gaps and Opportunities in Sensor-Based Medical Exploration Capabilities in Extravehicular Astronaut Suits

NASA’s Human Research Program has identified the need to improve their capability to predict estimated medical risks during exploration missions, as well as the need to provide computed medical decision support while minimizing medical resource utilization. From May 2017 through October 2017, a research team with the University of Mississippi Electrical Engineering Department conducted interviews with a dozen NASA personnel from the Human Research Program, Life Support Systems Technology Development, Game Changing Development Program, the Wyle Science, Technology and Engineering Group, and MEI Technologies. This report outlines the challenges and gaps identified as a result of these interviews in the Human Research Roadmap towards implementing a sensor-based medical monitoring system in EVA suits, as well as the opportunities in pursuing solutions towards these challenges. We describe the knowledge gaps in determining a clear definition for which measurable EVA suit environment and astronaut medical conditions are mission critical. We detail the current principle and special challenges of monitoring mission critical measurables in micro-gravity and zero-gravity environments with respect to their sensing ability. We then propose a three-stage research framework for meeting these objectives that is robust in scope, yet partitioned such that innovations or setbacks in one stage will not unduly harm progress. First, identifying a set mission critical measurable will enable innovations in sensor networks in EVA suits. We discuss proposed approaches to monitoring astronaut health and environments and relevant gaps. The second stage is using data from the sensor network as inputs to algorithms for determining when mission-critical parameters have been violated, as well as priorities for reporting that information. The third research area focuses on secure and reliable delivery of sensor information to the IV crewmembers, along with rendering of mission-critical information in a Heads-Up Display (HUD) worn by the astronaut. We discuss the current status of HUD technology in EVA suits and the challenges towards advancing that technology for mission deployment. We also discuss challenges in how the astronaut and IV crewmembers will utilize logged health and tracking information operationally. Finally, the status of the work already conducted under the proposed research framework is discussed.