Six-minute walk test closely correlates to “real-life” outdoor walking capacity and quality of life in patients with intermittent claudication

Effect of gait speed on clinical outcomes after crural and pedal bypass in patients with chronic limb-threatening ischemia

ObjectivesMany factors affect long-term outcomes after open bypass in patients with chronic limb-threatening ischemia (CLTI). Ambulatory status has been suggested to be associated with clinical outcomes, but there is limited knowledge on the effect of gait speed on outcomes. The purpose of this study is to evaluate the effect of gait speed assessed in a 6-min walk test (6MWT) on outcomes after crural and pedal bypass in patients with CLTI.MethodsA retrospective analysis was performed in patients with CLTI who underwent a 6MWT at 1 month after crural and pedal bypass at a single center from 2014 to 2021. Comparisons were made between those with high gait speed (HG group, 6-min walk distance (6MWD) > 288 m) and those with low gait speed (LG group, 6MWD ≤288 m). The primary endpoint was survival, and the secondary endpoints were graft patency, limb salvage, wound healing, major adverse cardiovascular events (MACEs), and hospital outcomes.ResultsOf 104 patients with CLTI who underwent a 6MWT after crural and pedal bypass, 46 (44%) and 58 (56%) were placed in the HG and LG groups, respectively. The LG group was older (p < .001), had more female subjects (p = .006), and had a higher prevalence of cerebrovascular disease (p = .042) and tissue loss (p = .007). The median follow-up was 36 (22-57) months. The HG group had significantly higher 3-year primary patency (65% vs 42%, p = .013), 3-year secondary patency (87% vs 66%, p = .018), 3-year overall survival (89% vs 58%, p < .001), and 3-year freedom from MACE (79% vs 67%, p = .039). The 3-year limb salvage and 12-month wound healing rates did not differ between the groups.ConclusionsGait speed in patients with CLTI after crural and pedal bypass was associated with survival, freedom from MACE, and graft patency but not with limb salvage and wound healing. A detailed study of walking ability in these patients may be needed in the future.

Minimal Clinically Important Difference in the Six-Minute Walking Distance 12 Months After Lumbar Spinal Stenosis Surgery

STUDY DESIGN

This was a prospective single-center study.

PURPOSE

This study aimed to calculate the minimal clinically important difference (MCID) of the six-minute walk distance (6MWD) postoperatively. Overview of the literature: The 6MWD and Zurich Claudication Questionnaire (ZCQ) have recently been used to evaluate the intermittent claudication of lumbar spinal stenosis (LSS). However, there is no report concerning the MCID of postoperative changes of 6MWD in patients with LSS.

METHODS

This prospective study included patients aged 60 or older who underwent surgery for LSS with intermittent claudication as the primary symptom at a single institution from 2022 to 2024. The 6MWD and the ZCQ were assessed preoperatively and 12 months postoperatively. The MCID was evaluated using an anchor-based approach using ZCQ. The Spearman's rank correlation coefficient was used to determine the correlation between the pre-and postoperative changes in 6MWD and ZCQ. The MCID was calculated using the receiver operating characteristic (ROC) curve. Calculated MCID and area under the curve (AUC) were evaluated by internal validation using the bootstrap method. A significance level of <0.05 was used, and bootstrap validation was performed with a 95% confidence interval.

RESULTS

One hundred and five patients were included in the study. The average preoperative and postoperative 6MWD were 282 meters and 385 meters, respectively (p<0.01). The ZCQ significantly improved from 2.64 to 1.73 postoperatively (p<0.01). Postoperative 6MWD and ZCQ correlated substantially with change (r=-0.58, p<0.01). In the anchor-based approach, 67 patients (63%) responded to the anchor ZCQ with an MCID of 80.0 m. This MCID had a sensitivity of 92.1%, a specificity of 76.1%, and an AUC of 90.6%, which was excellent. Internal validation showed moderate to excellent reliability with 95% confidence intervals for MCID and AUC ranging from 40 m to 100 m and 86% to 95%, respectively.

CONCLUSIONS

In this study, the MCID of postoperative changes of the 6MWD in patients with LSS was 80 m. This value helps evaluate the surgical results of patients with LSS.

Expanded-access use of elamipretide in a patient with membrane protein-associated neurodegeneration

This case report presents a progressively declining 17-year-old patient with membrane protein-associated neurodegeneration who demonstrated symptomatic improvements in her dysarthria, dysphagia, and gait, and objective improvements in her 6-minute walk test and 5 times sit-to-stand test during elamipretide treatment.

Assessment of Mobility Trajectories Using Wearable Inertial Sensors During Autologous Hematopoietic Cell Transplant

OBJECTIVE

This study aimed to characterize mobility patterns using wearable inertial sensors and serial assessment across autologous hematopoietic cell transplant (autoHCT) and investigate the relation between mobility and perceived function in patients with hematologic cancer.

DESIGN

Prospective longitudinal study.

SETTING

Hospital adult transplant clinic followed by discharge.

PARTICIPANTS

78 patients with hematological cancer receiving autoHCT.

MAIN OUTCOME MEASURES

Mobility was measured across 3 clinical phases (pretransplant, pre-engraftment, and post-engraftment) in using inertial sensors worn during prescribed performance tests in the hospital. Perceived function was assessed using validated provider-reported (Eastern Cooperative Oncology Group [ECOG] Performance Status Scale) and patient-reported [European Organization for Research and Treatment of Cancer Quality of Life Questionnaire [EORTC QLQ-C30]) measures. Trajectories of 5 selected mobility characteristics (turn duration, gait speed, stride time variability, double support time, and heel strike angle) across the clinical phases were also evaluated using piecewise linear mixed-effects models.

RESULTS

Using Principal Components Analysis, 4 mobility patterns were identified pretransplant: Gait Limitation, Sagittal Sway, Coronal Sway, and Balance Control. Gait Limitation measured pretransplant was significantly inversely associated with perceived function reported by the provider- (β = -0.11; 95% CI: -0.19, -0.02) and patient- (β = -4.85; 95% CI: -7.72, -1.99) post-engraftment in age-adjusted linear regression models. Mobility characteristics demonstrated immediate declines early pre-engraftment with stabilization by late pre-engraftment.

CONCLUSION

Patients with hematological cancer experiencing gait limitations pretransplant are likely to have worse perceived function post-engraftment. Mobility declines in early phases post-transplant and may not fully recover, indicating an opportunity for timely rehabilitation referrals. Wearable inertial sensors can be used to identify early mobility problems and patients who may be at risk for future functional decline who may be candidates for early physical rehabilitation.

A "test in-train out" program versus a "go home and walk" intervention for home-based exercise therapy in patients with peripheral artery disease: A randomized controlled trial

OBJECTIVE

In this single-blinded randomized controlled trial, we compared the "Test in-Train Out" structured home-based exercise program (TiTo-SHB) with the traditional "go home and walk" exercise intervention in people with peripheral artery disease (PAD).

METHODS

Peripheral artery disease patients at Leriche-Fontaine's stage II were randomized to receive TiTo-SHB or walking advice (C-WA). The TiTo-SHB group performed two daily 8-min sessions of pain-free interval walking at progressive low-to-moderate speed maintained with a metronome. The C-WA group was recommended to walk for 30 min at least three times per week and to endure claudication pain. Outcomes collected at baseline and at the end of the program (6 months) included: 6-min and pain-free walking distance (6MWD, PFWD), ankle-brachial index (ABI), 5-time sit-to-stand test (5STS), and health-related quality of life (HRQoL) by the VascuQoL-6 questionnaire.

RESULTS

A total of 68 patients were randomized (males n = 50; aged 73 ± 9; TiTo-SHB n = 34). At the end of the program, patients in the TiTo-SHB group compared with the C-WA group had significantly improved 6MWD (Δ + 60 ± 32 m vs. Δ - 5 ± 37 m; p < 0.001) and PFWD (Δ + 140 ± 92 m vs. Δ - 7 ± 87 m; p < 0.001). A significant between-group difference in favor of the TiTo-SHB group was also recorded for all the secondary outcomes, including 5STS (Δ - 2.6 ± 1.8 s vs. Δ + 0.8 ± 2.6 s; p < 0.001), ABI of the more impaired limb (Δ + 0.10 ± 0.11 vs. Δ + 0.02 ± 0.08; p = 0.003), and VascuQoL-6 score (Δ +2 ± 2 vs. -1 ± 4; p < 0.001).

CONCLUSION

In PAD patients with claudication, the pain-free in-home TiTo-SHB program was more effective in improving exercise capacity and HRQoL than the traditional walking advice recommendation.

Validation of the Lithuanian Version of the Walking Impairment Questionnaire in Patients with Peripheral Arterial Disease

Background and Objectives: The Walking Impairment Questionnaire (WIQ) is a short and simple tool to measure walking impairment for patients with peripheral arterial disease requiring no special equipment or trained staff. The aim of this study was to assess the validity and reliability of the culturally adapted Lithuanian WIQ version in patients with intermittent claudication. Materials and Methods: In total, 40 patients with intermittent claudication and ankle-brachial index < 0.90 participated in this study. Reliability and internal consistency of the questionnaire were assessed by the intra-class correlation coefficient (ICC) and Cronbach's alpha (α), respectively. Validity was determined by correlations between the WIQ scores and a subjective test (Quality of Life 5 Dimension Questionnaire 3 Level Version (EQ-5D-3L)) and objective tests (6 min walk test (6MWT), treadmill test, and ankle-brachial index). Results: The test-retest reliability was assessed as excellent with an intraclass correlation coefficient of 0.90. The values of Cronbach's alpha were 0.957 (I time) and 0.948 (II time) and indicated an excellent internal consistency. Statistically significant Spearman correlations were detected between the WIQ and walking distances on the 6MWT (rho 0.514, p < 0.001) and treadmill test (rho 0.515, p < 0.001). Higher WIQ scores were associated with longer walking distances and duration. Moderate negative and low negative correlations were found between the WIQ and EQ-5D-3L scores. Conclusions: The Lithuanian version of culturally adapted WIQ demonstrates reliability and validity for patients with intermittent claudication, supported by two different walking tests showing statistically significant moderate Spearman correlations.

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).

The Impact of Nordic Pole Walk Advice Alone or in Combination With Exercise Strategies on Daily Physical Activity in Patients With Intermittent Claudication: A Randomized Clinical Trial

OBJECTIVE

The impact of exercise interventions on physical activity (PA) remains undetermined in intermittent claudication, which is why it is important to include objectively measured PA as an additional endpoint. The aim of this prespecified secondary analysis of a randomized clinical trial was to investigate the impact of unsupervised Nordic pole walk advice (WA) alone or in combination with hospital-based supervised exercise (SEP) or home-based structured exercise (HSEP) on PA in patients with intermittent claudication.

METHODS

In total, 166 patients with intermittent claudication (mean age = 72 [SD = 7.4] y; 41% women) were randomized to 3 intermittent claudication-treatment strategies: WA, WA + SEP, or WA + HSEP. All patients received Nordic poles and standardized WA (≥30 min, 3 times weekly). Patients randomized to HSEP and SEP accepted participation in an additional 6-months exercise program. PA was measured with an accelerometer-based activPAL3 monitor for 7 days at baseline and at 3, 6, and 12 months. PA outcomes were steps per day, time spent within a stepping cadence ≥100 steps per minute, time spent upright, number of body transitions from sitting to standing, and number of sitting bouts of >30 minutes and >60 minutes.

RESULTS

At 1 year, no intergroup differences were observed in any of the PA variables, whereas significant intergroup differences were observed at 3 months regarding time spent within a stepping time cadence ≥100 steps per minute. The mean change for HSEP (2.47 [SD = 10.85] min) was significantly different from the mean change for WA (-3.20 [SD = 6.24] min). At 6 months, the number of sitting bouts (>60 min) for SEP was significantly different from WA (mean change = 0.24 [SD = 0.69] vs -0.23 [SD = 0.81]).

CONCLUSION

This study indicates that the addition of 6 months of HSEP or SEP does not improve PA at 1 year, as compared to unsupervised WA alone. Factors of importance for increasing PA in patients with intermittent claudication require further investigation.

IMPACT

At the 1-year follow-up, the addition of intermittent claudication-tailored additional exercise strategies did not improve daily PA in patients with intermittent claudication compared with unsupervised Nordic pole WA alone. Future studies may explore the role of behavior change techniques to increase PA in this patient group.

Systematic Review of the Use of the 6-Minute Walk Test in Measuring and Improving Prognosis in Patients With Ischemic Heart Disease

Introduction

The 6-minute walk test (6MWT) has been used for over 30 years to assess exercise capacity in patients with respiratory disease, and more recently, in those with heart failure. However, despite being a simple and reproducible test of real-world exercise capacity, its use in patients with ischemic heart disease (IHD) is less well accepted. We sought to review systematically the evidence surrounding the 6MWT in IHD.

Methods

We searched the Medline, PubMed, Embase, and Scopus databases for the following key terms: "six minute walk test/6 minute walk test/6MWT" and "angina/coronary artery disease/coronary disease/IHD/ischemic heart disease." We followed Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines to select publications for full-text review and analyzed the collated data.

Results

A total of 1228 unique papers were found, of which 71 were chosen for full-text review and 37 for detailed analysis. Most (23) concerned the effect on 6MWT distance (6MWTd) of cardiac rehabilitation, with measurements commenced after an intervention (acute myocardial infarction, n = 4; open heart surgery (OHS), n = 5; percutaneous coronary intervention (PCI), n = 3; or other, n = 11). The effect on 6MWTd of OHS was investigated in 6 studies and of PCI in one study. The 6MWT is a useful measurement of physical capacity; data are limited on its ability to assess benefit following PCI.

Conclusions

The 6MWT has been studied inconsistently in IHD. The majority of data are on patients before and after CR. Data are limited concerning the effect on 6MWTd of OHS or PCI. The available data support the 6MWT as a measure of change in performance status following coronary intervention. More work is required to confirm this hypothesis.

Objective assessment of functional capacity in patients with peripheral artery disease: a narrative review

INTRODUCTION

Peripheral artery disease (PAD) patients with claudication symptoms exhibit impaired functional capacity, which has been associated with disease severity, worse quality of life and higher risk of cardiovascular events. Different tests have been used to assess functional capacity in PAD patients. Therefore, understanding the characteristics, strengths and limitations of these tests are important to support the choice of tests to be used in clinical practice.

AREAS COVERED

This review summarizes the main methods to assess functional capacity in PAD patients, discussing their psychometric properties, applications, and limitations.

EXPERT OPINION

Robust evidence supports the use of treadmill and six-minute walk tests in PAD patients, as their results are associated with clinically meaningful outcomes, adequate psychometric properties and are sensitive to effects of interventions. On the other hand, other functional tests (Shuttle-walk test, outdoor walking capacity test, timed-up and go, four-meter walk test, heel-rise test, short physical performance battery and modified physical performance battery) are related to activities of daily living and do not require sophisticated equipment and can be easily used in clinical practice. However, these other tests still need evidence regarding their clinical relevance, reliability, and ability to detect long-term intervention changes, providing further investigation directions.

Using Wearable Inertial Sensors to Assess Mobility of Patients With Hematologic Cancer and Associations With Chemotherapy-Related Symptoms Before Autologous Hematopoietic Stem Cell Transplant: Cross-sectional Study

BACKGROUND

Wearable sensors could be a simple way to quantify and characterize mobility in patients with hematologic cancer scheduled to receive autologous hematopoietic stem cell transplant (autoHSCT) and how they may be related to common treatment-related symptoms and side effects of induction chemotherapy.

OBJECTIVE

We aimed to conduct a cross-sectional study comparing mobility in patients scheduled to receive autoHSCT with that in healthy, age-matched adult controls and determine the relationships between patient mobility and chemotherapy-related symptoms.

METHODS

Patients scheduled to receive autoHSCT (78/156, 50%) and controls (78/156, 50%) completed the prescribed performance tests using wearable inertial sensors to quantify mobility including turning (turn duration and number of steps), gait (gait speed, stride time, stride time variability, double support time, coronal trunk range of motion, heel strike angle, and distance traveled), and balance (coronal sway, coronal range, coronal velocity, coronal centroidal frequency, sagittal sway, sagittal range, sagittal velocity, and sagittal centroidal frequency). Patients completed the validated patient-reported questionnaires to assess symptoms common to chemotherapy: chemotherapy-induced peripheral neuropathy (Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity subscale), nausea and pain (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire), fatigue (Patient-Reported Outcomes Measurement Information System Fatigue Short Form 8a), vertigo (Vertigo Symptom Scale-short form), and depression (Center for Epidemiological Studies-Depression). Paired, 2-sided t tests were used to compare mobility between patients and controls. Stepwise multivariable linear regression models were used to evaluate associations between patient mobility and symptoms.

RESULTS

Patients aged 60.3 (SD 10.3) years had significantly worse turning (turn duration; P<.001), gait (gait speed, stride time, stride time variability, double support time, heel strike angle, stride length, and distance traveled; all P<.001), and balance (coronal sway; P<.001, range; P<.001, velocity; P=.02, and frequency; P=.02; and sagittal range; P=.008) than controls. In patients, high nausea was associated with worse stride time variability (ß=.001; P=.005) and heel strike angle (ß=-.088; P=.02). Pain was associated with worse gait speed (ß=-.003; P=.003), stride time variability (ß=.012; P=.02), stride length (ß=-.002; P=.004), and distance traveled (ß=-.786; P=.005). Nausea and pain explained 17% to 33% and 14% to 36% of gait variance measured in patients, respectively.

CONCLUSIONS

Patients scheduled to receive autoHSCT demonstrated worse mobility in multiple turning, gait, and balance domains compared with controls, potentially related in part to nausea and pain. Wearable inertial sensors used in the clinic setting could provide granular information about mobility before further treatment, which may in turn benefit from rehabilitation or symptom management. Future longitudinal studies are needed to better understand temporal changes in mobility and symptoms across the treatment trajectory to optimally time, design, and implement strategies, to preserve functioning in patients with hematologic cancer in the long term.

The Value of a Standardized Knee Functional Assessment in Predicting the Outcomes of Total Knee Arthroplasty

Questionnaires and physical tests are tools to determine the ability of an individual to perform tasks of the daily living. In our institution, a standardized knee performance evaluation including patient-reported outcome measures (PROMs) and physical performance tests has been applied to all patients undergoing total knee arthroplasty (TKA). Our goal was to identify which preoperative tools influence the outcomes of a TKA and if physical performance tests can be of value if used along with PROMs in predicting functional outcomes. Classification and regression tree was used to analyze which preoperative factors influence function after TKA. Western Ontario and McMaster Universities Arthritis Index (WOMAC) function (WOMAC-F), 6-minute walk test (6MWT), and timed up and go (TUG) test at the 12th postoperative month were the dependent variables. Age, body mass index, preoperative WOMAC function and pain score, muscle strength, 6MWT, and TUG test score were used as preoperative predictors of dependent variables. TUG ≤19.3 seconds and age <62 years were preoperative predictors of better scores in the WOMAC-F (5.5). Strength of extensor muscles of the nonoperated knee ≥99.43 N·m/kg and 6MWT> 328 m were preoperative predictors of a better postoperative 6MWT (499 m). TUG <12.3 seconds and 6MWT ≥421 m were preoperative predictors of better postoperative TUG (7.3 seconds). Preoperative performance in physical tests had an influence on postoperative outcome scores than PROMs after TKA. Less age, good muscular strength, greater capacity of walking, and smaller TUG times were associated with better outcomes.

Beyond the Patient's Report: Self-Reported, Subjective, Objective and Estimated Walking Disability in Patients with Peripheral Artery Disease

Among patients with peripheral artery disease, an altered estimation of walking ability reported to the physician may influence the choice of treatment. We compared claudication distance (CD) values reported by patients or assessed by validated protocols to elaborate a formula capable of estimating more reliable values. Three hundred fifty-nine patients with claudication were measured at the time of entry into a rehabilitation program. Walking performance was obtained by patients' reports (self-reported claudication distance, SR-CD) and was directly assessed to determine the claudication and maximal walking distance by the 6-min test (6-CD and 6-MWD) and an incremental treadmill test (T-CD and T-MWD). The degree of muscle deoxygenation was objectively determined at the calf by near-infrared spectroscopy (NIRS) during the treadmill test. Among the 289 subjects analyzed, SR-CD exceeded both 6-CD and T-CD (+155 and +182 m, respectively). SR-CD was moderately correlated with T-CD (r = 0.30), 6-CD (r = 0.32), and 6-MWD (r = 0.29) but not with muscle deoxygenation per meter walked, unlike T-CD and 6-CD. A formula adjusted for the presence of diabetes reduced patient overestimation by 92%. The patient's reported claudication distance was generally overestimated compared to objective measures, and it was made more reliable through a corrective factor for easy use in a clinical setting.

Measuring Outdoor Walking Capacities Using Global Positioning System in People with Multiple Sclerosis: Clinical and Methodological Insights from an Exploratory Study

We aimed at showing how Global Positioning System (GPS) along with a previously validated speed processing methodology could be used to measure outdoor walking capacities in people with multiple sclerosis (MS). We also deal with methodological issues that may occur when conducting such measurements, and explore to what extent GPS-measured outdoor walking capacities (maximal walking distance [MWD_GPS] and usual walking speed) could be related to traditional functional outcomes (6-min total walking distance) in people with MS. Eighteen people with MS, with an Expanded Disability Status Scale score ≤6, completed a 6-min walking test and an outdoor walking session (60 min maximum) at usual pace during which participants were wearing a DG100 GPS receiver and could perform several walking bouts. Among the 12 participants with valid data (i.e., who correctly completed the outdoor session with no spurious GPS signals that could prevent the detection of the occurrence of a walking/stopping bout), the median (90% confidence interval, CI) outdoor walking speed was 2.52 km/h (2.17; 2.93). Ten participants (83% (56; 97)) had ≥1 stop during the session. Among these participants, the median of MWD_GPS was 410 m (226; 1350), and 40% (15; 70) did not reach their MWD_GPS during the first walking bout. Spearman correlations of MWD_GPS and walking speed with 6-min total walking distance were, respectively, 0.19 (-0.41; 0.95) and 0.66 (0.30; 1.00). Further work is required to provide guidance about GPS assessment in people with MS.

Validation of an Adapted Questionnaire for Outdoor Walking Among Older Adults: The CHAMPS-OUTDOORS

The aim of this study was to examine the construct and known-groups validity of the total score of five items adapted from the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire to measure outdoor walking (CHAMPS-OUTDOORS) in older adults. Data from the baseline assessment of the Getting Older Adult OUTdoors (GO-OUT) trial were used. Construct validity of the CHAMPS-OUTDOORS used objective measures of outdoor walking (accelerometry-GPS), Ambulatory Self-Confidence Questionnaire, RAND-36, 6-min walk test, 10-m walk test, and Mini-Balance Evaluation System Test. For known-groups validity, we compared the CHAMPS-OUTDOORS of those who walked < or ≥1.2 m/s. Sixty-five participants had an average age of 76.5 ± 7.8 years. The CHAMPS-OUTDOORS was moderately correlated with total outdoor walking time (r = .33) and outdoor steps (r = .33) per week measured by accelerometry-GPS, and weakly correlated with Mini-Balance Evaluation System Test score (r = .27). The CHAMPS-OUTDOORS did not distinguish known groups based on crosswalk speed (p = .33). The CHAMPS-OUTDOORS may be used to assess outdoor walking in the absence of accelerometry GPS. Further research examining reliability is needed.

Differences in Physical Activity between Patients with Peripheral Artery Disease and Healthy Subjects

Objectives

Peripheral artery disease (PAD) is a significant prognostic marker of poor long-term survival due to limited physical activity associated with various functional problems, such as intermittent claudication. A physically active lifestyle has the potential to modify peripheral artery risk factors and promote general health. While low daily physical activity levels have been recognized in the population of PAD, the exact level has yet to be quantified due to lack of research. The aim of the present study was to compare physical activity level (PAL) and time spent at activities of different intensity levels between patients with PAD and healthy individuals. The study subjects were 10 patients with PAD and 10 age-matched healthy control subjects. We measured the time spent at light, moderate, or vigorous physical activity using triaxial accelerometer and calculated PAL. Intermittent claudication onset distance and maximum walking distance were defined as the distance walked at which the subject first reported leg pain and the distance at which the subject was unable to continue walking because of leg pain, respectively.

Results

Our results showed (i) lower PAL in patients with PAD compared with the controls; (ii) while there was no significant difference in the high-intensity activity between the two groups, the light- and moderate-intensity activities of the PAD group were significantly lower than the controls, the time spent at moderate-intensity activity was approximately 50% less; and (iii) among patients with PAD, low PAL did not correlate directly with intermittent claudication.

Conclusions

PAD patients limit the amount of their physical activity, especially light and moderate intensities. Our study highlights the importance of spending more time walking in daily life.

Association of six-minute walk distance with subsequent lower extremity events in peripheral artery disease

The prognostic significance of the six-minute walk distance for lower extremity events in people with peripheral artery disease (PAD) is unknown. This longitudinal study assessed whether a poorer six-minute walk distance at baseline was associated with higher rates of subsequent lower extremity atherosclerotic disease events in PAD. A total of 369 patients (mean age 69.4 ± 10.0 years; mean ankle-brachial index (ABI) 0.67 ± 0.17; 31% women; 30% black individuals) from Chicago-area medical centers with PAD were enrolled. Participants underwent baseline six-minute walk testing and returned for annual study visits. Lower extremity events consisted of one or more of the following: ABI decline greater than 15% or medical record adjudicated lower extremity revascularization, critical limb ischemia, or amputation. At a mean follow-up of 33.3 months, lower extremity events occurred in 66/123 (53.7%) people in the first (worst) tertile of six-minute walk performance, 55/124 (44.4%) in the second tertile, and 56/122 (45.9%) in the third (best) tertile. After adjusting for age, sex, race, ABI, comorbidities, and other confounders, participants in the first (worst) tertile of six-minute walk distance at baseline had higher rates of lower extremity events during follow-up, compared to those in the best tertile at baseline (HR = 1.74, 95% CI 1.17-2.60, p = 0.0067). Among people with PAD, a poorer six-minute walk distance was associated with higher rates of subsequent lower extremity PAD-related events after adjusting for confounders. Further study is needed to determine whether interventions that improve six-minute walk distance can reduce lower extremity adverse events in people with PAD.

Combined Aerobic and Resistance Exercise in Walking Performance of Patients With Intermittent Claudication: Systematic Review

Background: The short-term benefits of aerobic and resistance exercise in subjects affected by Peripheral Arterial Disease (PAD) are scarcely examined in interaction. This study aimed to identify the effects of combined aerobic and resistance exercise programs on walking performance compared with isolated aerobic exercise or with the usual care in patients with intermittent claudication.

Methods: A systematic review was conducted following the PRISMA statement. A total of five electronic databases were searched (until October 2019) for randomized and non-randomized controlled trials. The focus comprised PAD patients with intermittent claudication who performed a combined aerobic and resistance exercise program that assessed the walking performance.

Results: Seven studies include combined aerobic and resistance exercise vs. isolated aerobic or vs. usual care. The studies represented a sample size of 337 participants. The follow-up ranged from 4 to 12 weeks, 2 to 5 times-per-week. The risk of bias in the trials was a deemed moderate-to-high risk. After the interventions, the percent change in walking performance outcomes had a large variation. In the combined and isolated aerobic programs, the walking performance always improved, while in the usual care group oscillates between the deterioration and the improvement in all outcomes. Combined exercise and isolated aerobic exercise improved the claudication onset distance from 11 to 396%, and 30 to 422%, the absolute claudication distance from 81 to 197%, and 53 to 121%, and the maximal walking distance around 23 and 10%, respectively.

Conclusions: Currently, there is insufficient evidence about the effects of combined aerobic and resistance exercise compared to isolated aerobic exercise or usual care on walking performance. However, despite the low quality of evidence, the combined aerobic and resistance exercise seems to be an effective strategy to improve walking performance in patients with intermittent claudication. These combined exercise modes or isolated aerobic exercise produce positive and significant results on walking performance. The usual care approach has a trend to deteriorate the walking performance. Thus, given the scarcity of data, new randomized controlled trial studies that include assessments of cardiovascular risk factors are urgently required to better determine the effect of this exercise combination.

Test-retest reliability, agreement, and minimal detectable change in the 6-minute walk test in patients with intermittent claudication

OBJECTIVE

Standardized walk tests are important for objective assessment of walking distance in patients with intermittent claudication (IC). The 6-minute walk test (6MWT) has been suggested to correlate more closely than testing on a treadmill with everyday ambulatory function, but its measurement properties have hardly been studied in IC. The aim of this study was to determine the test-retest reliability, agreement, standard error of measurement (SEM), and minimal detectable change of the 6MWT in patients with IC.

METHODS

This reliability and agreement study recruited 102 patients with stable IC (mean age, 72 ± 7.4 years; 43 women) from the vascular surgery outpatient clinic at Sahlgrenska University Hospital in Sweden. The patients performed the 6MWT twice, with at least 30 minutes of rest between tests. To determine test-retest reliability, the intraclass correlation coefficient was calculated. Bland-Altman plots were used to measure agreement.

RESULTS

The mean walking distance in both test and retest was 397.8 m (standard deviation, 81.2 m; N = 100), and the individual walking distance varied from 175 to 600 m. Excellent test-retest reliability for the 6MWT (intraclass correlation coefficient, 0.95; 95% confidence interval, 0.9-0.97) was observed. The SEM was 16.6 m (95% confidence interval, 14.6-19.3), the SEM percentage was 4.2%, and the minimal detectable change was 46 m. Five observations (5%) were positioned outside the limits of agreement; there was a small proportional bias, and the scatter of values for differences decreased as the average values increased.

CONCLUSIONS

The excellent test-retest reliability implies that it is sufficient for a patient with IC to perform the 6MWT once, at every test occasion. For the individual, an improvement or deterioration in maximum walking distance of >46 m after an intervention would be required to be 95% confident that the change is significant. Being a simple and clinically useful test, the 6MWT can be widely used to evaluate the effects of different interventions in patients with IC.

Safety of Nebulized Epinephrine in Smoke Inhalation Injury

This pilot study was conducted to profile safety of nebulized racemic epinephrine when used as a therapy for smoke inhalation injury in severely burned children. We enrolled 16 patients who were 7 to 19 years of age ([mean ± SD], 12 ± 4 years) with burns covering more than 30% of the TBSA (55 ± 17%) and smoke inhalation injury, as diagnosed by bronchoscopy at burn center admission. Patients were randomized to receive either standard of care (n = 8), which consisted of nebulized acetylcysteine, nebulized heparin, and nebulized albuterol, or to receive standard of care plus nebulized epinephrine (n = 8). Primary endpoints were death, chest pain, and adverse changes in cardiopulmonary hemodynamics (arrhythmia, arterial blood pressure, electrocardiographic [ST segment] changes, and peak inspiratory pressure). Additional endpoints included total days on ventilator, pulmonary function, and physiological cardiopulmonary measurements at intensive care unit discharge. No adverse events were observed during or after the nebulization of epinephrine, and no deaths were reported that were attributable to the administration of nebulized epinephrine. The groups did not significantly differ with regard to age, sex, burn size, days on ventilator, pulmonary function, or cardiopulmonary fitness. Results of this pilot trial indicate epinephrine to be safe when administered to pediatric burn patients with smoke inhalation injury. Current data warrant future efficacy studies with a greater number of patients.

Identifying content gaps in health status measures for intermittent claudication using the International Classification of Functioning, Disability and Health

OBJECTIVE

The Walking Impairment Questionnaire (WIQ) and Intermittent Claudication Questionnaire (ICQ) are commonly used patient-reported functional outcome measures for intermittent claudication, but their functional representation has not been characterized. The World Health Organization's International Classification of Functioning, Disability and Health (ICF) framework comprehensively describes health-related function and has been used to evaluate health status and quality of life (QOL) measures. We applied a content analysis technique commonly used in functional rehabilitation research to evaluate ICF domains represented by WIQ and ICQ to characterize their health status and functional representation.

METHODS

The overall perspective of each question was assigned as health status-function, health status-disability, Environment-facilitator, Environment-barrier, or QOL. All meaningful concepts in each question were identified and linked to the most appropriate and precise ICF code from the hierarchy of component, chapter, or category using the validated technique. A 20% random sample of questions was secondarily coded with disagreements resolved by discussion.

RESULTS

Codability was agreed upon for 87% of questions; agreement was 100% on component and chapter and 88% on category. WIQ contains 18 concepts among 14 questions (1.3 concepts per question); all questions are from the health status-disability perspective. All WIQ concepts are from the "Activities/Participation-d" ICF component, "Mobility-d4" chapter. "Walking long distances" (d4501, >1 km) is omitted. ICQ contains 37 codable concepts among 16 questions (2.3 concepts per question). Thirteen questions are from health status-disability perspective, three from QOL. Sox of the nine chapters of the "Activities/Participation-d" ICF component are represented by 20 of 37 concepts; 11 of 20 in the "Mobility-d4" chapter. The other "Activities/Participation-d" chapters and categories in ICQ are "Learning/applying knowledge" ("thinking-d163"), "General tasks/demands" ("carrying out daily routine-d230"), "Domestic life" ("shopping-d6200," "doing housework-d640"), "Major life areas" ("Maintaining a job-d8451"), and "Community life" ("socializing-d9205," "hobbies-d9204"). "Body Functions-b" ICF component is represented 11 times, covering pain, numbness, emotion, mood, and cardiovascular functions. "Body Structures-s" is represented three times as lower extremity. Neither WIQ nor ICQ specifically addresses "Walking on different surfaces," (64,502) "Walking around obstacles" (d4503), or "Moving around using equipment" (d465), which includes assistive devices. Walking on an incline is not addressed in WIQ, ICQ, or the ICF.

CONCLUSIONS

Applying this ICF-based content assessment methodology to patient-reported vascular disease outcome measures is feasible, representing a novel method of assessing such instruments. WIQ's scope is limited; it does not address functional capacity and covers only health status pertaining to walking disability. The ICQ is more inclusive, but concept density may obscure meaning. Neither instrument is functionally comprehensive and both have significant omissions that should be considered for inclusion.

Stent placement in the superficial femoral and proximal popliteal arteries with the innova self-expanding bare metal stent system

OBJECTIVES

The SuperNOVA trial was designed to evaluate performance of the Innova Vascular Self-Expanding Stent System (Boston Scientific, Marlborough, MA) for treating lesions in the femoropopliteal arteries.

METHODS

Patients with chronic lower limb peripheral artery disease (Rutherford category 2, 3, or 4) and atherosclerotic lesions in the native superficial femoral and/or proximal popliteal artery (lengths 30-190 mm) were enrolled in this single-arm, multinational study. Major adverse events (MAEs) were defined as all-cause death through 1 month, target limb major amputation, and target lesion revascularization (TLR). Vessel primary patency was defined as core laboratory-adjudicated duplex ultrasonography-derived peak systolic velocity ratio ≤2.4 in the absence of TLR, surgical bypass of the target lesion, or major amputation of the target limb. Primary safety and efficacy endpoints were evaluated at 12 months, with follow-up through 24 months also reported.

RESULTS

SuperNOVA patients (N = 299; mean age 67.4 ± 9.7 years, 74% men, 41% with diabetes) had a mean lesion length of 93.2 mm. The MAE-free rate was 99.7% at 30 days, 85.8% at 12 months, and 77% at 24 months. Kaplan-Meier estimates of primary patency and TLR-free rates were 68.7% and 78.0%, respectively, at 24 months. Clinical improvements were sustained through 2 years, with 80% of patients displaying no or minimal symptoms (Rutherford category 0-1) at 24 months.

CONCLUSIONS

In the SuperNOVA study, the Innova Stent System demonstrated an excellent safety profile and acceptable clinical outcomes despite the challenging anatomical characteristics of the lesions. © 2017 Wiley Periodicals, Inc.

Two-year results from a randomized clinical trial of revascularization in patients with intermittent claudication

Background

Intermittent claudication is associated with significant impairment of health-related quality of life. The use of revascularization techniques to improve health-related quality of life remains controversial.

Methods

Patients with intermittent claudication due to iliac or femoropopliteal peripheral artery disease were enrolled in the IRONIC trial. They were randomized to either best medical therapy (BMT), including a structured, non-supervised exercise programme, or revascularization with either endovascular or open techniques in addition to BMT. The primary outcome was health-related quality of life at 2 years assessed using the Short Form 36 (SF-36®) questionnaire. Secondary outcomes included VascuQoL questionnaire results, treadmill walking distances and achievement of patient-specified treatment goals.

Results

Both randomized groups had improved health-related quality of life and treadmill walking distance at 2-year follow-up. Overall SF-36® physical component summary score, three SF-36® physical domain scores, overall VascuQoL score, and three of five VascuQoL domain scores showed significantly greater improvement in the group that also received invasive treatment. Intermittent claudication distance on a graded treadmill improved more in the revascularization + BMT group (117 versus 55 m; P = 0·003) whereas maximum walking distance and 6-min walk test distance were similar. Some 44 per cent of patients in the revascularization + BMT group reported they had fully achieved their treatment goal versus 10 per cent in the BMT group.

Conclusion

A revascularization strategy with unsupervised exercise improved health-related quality of life and intermittent claudication distance more than standard BMT and an unsupervised exercise programme in patients with lifestyle-limiting claudication. Registration number: NCT01219842 (http://www.clinicaltrials.gov).

Intensive walking exercise for lower extremity peripheral arterial disease: A systematic review and meta-analysis

BACKGROUND

Supervised treadmill exercise is the recommended therapy for peripheral arterial disease (PAD) patients with intermittent claudication (IC). However, most PAD patients do not exhibit typical symptoms of IC. The aim of the present study was to explore the efficacy and safety of intensive walking exercise in PAD patients with and without IC.

METHODS

The PubMed, Embase and Cochrane Library databases were systematically searched. Randomized controlled trials comparing the effects of intensive walking exercise with usual care in patients with PAD were included for systematic review and meta-analysis.

RESULTS

Eighteen trials with 1200 patients were eligible for the present analysis. Compared with usual care, intensive walking exercise significantly improved the maximal walking distance (MWD), pain-free walking distance, and the 6-min walking distance in patients with PAD (P < 0.00001 for all). Subgroup analyses indicated that a lesser improvement in MWD was observed in the subgroup with more diabetes patients, and that the subgroup with better baseline walking ability exhibited greater improvement in walking performance. In addition, similar improvements in walking performance were observed for exercise programs of different durations and modalities. No significant difference was found in adverse events between the intensive walking and usual care groups (relative risk 0.84; 95% confidence interval 0.51, 1.39; P = 0.50).

CONCLUSIONS

Regardless of exercise length and modality, regularly intensive walking exercise improves walking ability in PAD patients more than usual care. The presence of diabetes may attenuate the improvements in walking performance in patients with PAD following exercise.

Consumption of star fruit juice on pro-inflammatory markers and walking distance in the community dwelling elderly

PURPOSE

This study aimed to evaluate the effect of star fruit juice supplementation on tumor necrosis factor-alpha (TNF-α), interleukin-23 (IL-23) and interleukin-2 (IL-2), nitric oxide (NO), and 6 min walking distance (6MWD) in a group of elderly individuals.

METHODS

Twenty-nine individuals (20 males, 9 females) with a mean age of 72.4±8.3 years completed this study. A two-week control period was followed by four weeks of 100g fresh star fruit juice consumption twice per day after meals.

RESULTS

Plasma TNF-α, IL-23, IL-2, NO and the 6MWD were evaluated twice during the control period (weeks 0 and 2) and once after the star fruit juice consumption (week 6).

RESULTS

The results showed that all parameters in the blood did not change significantly during the control period. After 4 weeks of star fruit juice consumption, a significant reduction in NO, TNF-α and IL-23 was found; however, there was no change in IL-2. Moreover, the 6MWD increased significantly at week 6, when compared to that at week 0 and 2. Furthermore, the results also showed a significantly positive and negative correlation of NO and TNF-α to the 6MWD, but no correlation of IL-23 and IL-2.

CONCLUSION

This preliminary study concluded that consumption of star fruit juice at 100g twice daily for one month can significantly depress the pro-inflammation cytokines: TNF-α, IL-23, and NO, while increasing walking distance. Low TNF-α and high NO also present a significant correlation to walking capacity in elderly individuals.

Is asymptomatic peripheral arterial disease associated with walking endurance in patients with COPD?

Objective

Symptomatic peripheral arterial disease (PAD) is associated with impaired walking endurance in patients with chronic obstructive pulmonary disease (COPD). However, it is unknown whether asymptomatic PAD is associated with impaired walking endurance in patients with COPD.

Methods

This prospective cross-sectional study enrolled 200 COPD patients (mean age: 70.9 years) who volunteered to perform ankle-brachial index (ABI) and 6-minute walk test (6MWT) consecutively. Demographic data, lung function, dyspnea scales, and cardiovascular risk factors were recorded. The ABI was used to detect PAD (ABI <0.90). All patients were free of PAD symptoms at enrollment.

Results

Of the 200 COPD patients, 17 (8.5%) were diagnosed with asymptomatic PAD. The COPD patients without asymptomatic PAD did not walk significantly further on the 6MWT than the COPD patients with asymptomatic PAD (439±86 m vs 408±74 m, P=0.159). The strongest correlation with the distance walked on the 6MWT was Medical Research Council dyspnea scale (r²=−0.667, P<0.001), followed by oxygen-cost diagram (r²=0.582, P<0.001) and forced expiratory volume in 1 second (r²=0.532, P<0.001). In multivariate linear regression analysis, only age, forced expiratory volume in 1 second, and baseline pulse oximetry were independently correlated with the distance covered on the 6MWT (P<0.05). However, body mass index, baseline heart rate, and ABI were not correlated with the distance covered on the 6MWT.

Conclusion

Asymptomatic PAD is not associated with walking endurance in patients with COPD. Therefore, it is important to detect and treat asymptomatic PAD early so that COPD patients do not progress to become exercise intolerant. Limited by the small sample size and predominantly male (99%) population in the study, further large-scale prospective studies are needed to verify the results.

Clinical Interest of Ambulatory Assessment of Physical Activity and Walking Capacity in Peripheral Artery Disease

The purpose of the present review was to provide, for the first time, a comprehensive analysis and synthesis of the available studies that highlighted the clinical interest of the ambulatory assessment of either physical activity (PA) or walking capacity in patients with lower extremity peripheral artery disease (PAD). We identified 96 related articles published up to March 2015 through a computer-assisted search of the MEDLINE, EMBASE, and Web of Science databases. Ambulatory-measured PA or related energy expenditure (EE) in PAD patients was performed in 87 of the 96 included studies. The main clinical interests of these measurements were (a) the assessment of PA/EE pattern; (b) the characterization of walking pattern; and (c) the control of training load during home-based walking programs. Ambulatory-measured walking capacity was performed in the remaining studies, using either Global Positioning System receivers or the Peripheral Arterial Disease Holter Control device. Highlighted clinical interests were (a) the assessment of community-based walking capacity; (b) the use of new outcomes to characterize walking capacity, besides the conventional absolute claudication distance; and (c) the association with the patient's self-perception of walking capacity. This review also provides for the clinicians step-by-step recommendations to specifically assess PA or walking capacity in PAD patients.

Global positioning system use in the community to evaluate improvements in walking after revascularization: a prospective multicenter study with 6-month follow-up in patients with peripheral arterial disease

Revascularization aims at improving walking ability in patients with arterial claudication. The highest measured distance between 2 stops (highest-MDCW), the average walking speed (average-WSCW), and the average stop duration (average-DSCW) can be measured by global positioning system, but their evolution after revascularization is unknown.We included 251 peripheral artery diseased patients with self-reported limiting claudication. The patients performed a 1-hour stroll, recorded by a global positioning system receiver. Patients (n = 172) with confirmed limitation (highest-MDCW <2000m) at inclusion were reevaluated after 6 months. Patients revascularized during the follow-up period were compared with reference patients (ie, with unchanged lifestyle medical or surgical status). Other patients (lost to follow-up or treatment change) were excluded (n = 89).We studied 44 revascularized and 39 reference patients. Changes in highest-MDCW (+442 vs. +13 m) and average-WSCW (+0.3 vs. -0.2 km h) were greater in revascularized than in reference patients (both P < 0.01). In contrast, no significant difference in average-DSCW changes was found between the groups. Among the revascularized patients, 13 (29.5%) had a change in average-WSCW, but not in highest-MDCW, greater than the mean + 1 standard deviation of the change observed for reference patients.Revascularization may improve highest-MDCW and/or average-WSCW. This first report of changes in community walking ability in revascularized patients suggests that, beyond measuring walking distances, average-WSCW measurement is essential to monitor these changes. Applicability to other surgical populations remains to be evaluated.

REGISTRATION

http://www.clinicaltrials.gov/ct2/show/NCT01141361.