Walking performance in individuals with lumbar spinal stenosis-possible outcome measures and assessment of known-group validity.

BACKGROUND CONTEXT: One of the primary goals of treatments received by individuals with lumbar spinal stenosis with neurogenic claudication is to improve walking ability. Thus, a thorough and valid assessment of walking ability in patients with lumbar spinal stenosis is needed. Duration of continuous walking and steps per day could be relevant when evaluating walking ability in daily living. PURPOSE: To describe and evaluate a method for estimating continuous walking periods in daily living and to evaluate the known-group validity of steps per day in individuals with lumbar spinal stenosis. STUDY DESIGN: This is a cross-sectional observational study. PATIENT SAMPLE: The study contains three study groups: individuals with lumbar spinal stenosis, individuals with low back pain, and a background population from the Lolland-Falster Health Study (LOFUS). OUTCOME MEASURES: Participants in all three study groups wore an accelerometer on the thigh for seven days. METHODS: Accelerometer data were processed to summarize the continuous walking periods according to their length: the number of short (4-9 seconds), moderate (10-89 seconds), and extended (≥90 seconds) continuous walking periods per day, and the number of steps per day. Results from the three groups were compared using negative binomial regression with lumbar spinal stenosis as the reference level. RESULTS: Continuous walking periods of moderate length were observed 1.48 (95% CI 1.27, 1.72) times more often in individuals from the background population than in individuals with LSS. Continuous walking periods of extended length were observed 1.53 (95% CI 1.13, 2.06) times more often by individuals with low back pain and 1.60 (95% CI 1.29, 1.99) times more often by individuals from the background population. The number of steps per day was 1.22 (95% CI 1.03, 1.46) times larger in individuals with LBP and 1.35 (95% CI 1.20, 1.53) times larger in individuals from background population. CONCLUSIONS: The impact of neurogenic claudication on walking ability in daily living seems possible to describe by continuous walking periods along with steps per day. The results support known-group validity of steps per day. This is the next step toward a clinically relevant and comprehensive assessment of walking in daily living in individuals with lumbar spinal stenosis.

Telephone Health Coaching and Remote Exercise Monitoring (TeGeCoach) in Peripheral Arterial Occlusive Disease.

BACKGROUND: Supervised exercise programs are used to treat intermittent claudication (IC). Home-based exercise programs have been developed to lower barriers to participation. We studied the effects of one such exercise program (TeGeCoach) on self-reported walking ability in patients with IC. METHODS: In a pragmatic multicenter randomized controlled trial (registration number NCT03496948), 1982 patients with symp - tomatic IC insured by one of three German statutory health insurance funds received either telephone health coaching with remote exercise monitoring (TeGeCoach; n = 994) or routine care (n = 988). The primary outcome was the change in Walking Impairment Questionnaire (WIQ) scores after 12 and 24 months in the intention-to-treat population. The secondary outcomes were healthrelated quality of life, symptoms of depression or anxiety, health competence, patient activation, alcohol use, and nicotine depen - dence. RESULTS: There was a significant group difference in WIQ score in favor of TeGeCoach (p < 0.0001), amounting to 6.30 points at 12 months (Bonferroni-corrected 95% CI [4.02; 8.59], Cohen's d = 0.26) and 4.55 points at 24 months ([2.20; 6.91], d = 0.19). Some of the secondary outcomes also showed positive results in favor of TeGeCoach at 12 months with small effect sizes (d ≥ 0.20), including physical health-related quality of life and patient activation. The average daily step count was not higher in the TeGeCoach group. CONCLUSION: Significant improvements regarding symptom burden demonstrate the benefit of a home-based exercise program and thus expand the opportunities for guideline-oriented treatment of IC. Future studies should additionally address the effect of home-based exercise programs on clinical variables by means of, for example, the 6-minute walk test.

Registry Assessment of Peripheral Interventional Devices objective performance goals for superficial femoral and popliteal artery peripheral vascular interventions.

BACKGROUND: The Superficial Femoral Artery-Popliteal EvidencE Development Study Group developed contemporary objective performance goals (OPGs) for peripheral vascular interventions (PVI) for superficial femoral artery (SFA)-popliteal artery disease using the Registry Assessment of Peripheral Interventional Devices. METHODS: The Society for Vascular Surgery Vascular Quality Initiative PVI registry from January 2010 to October 2016 was used to develop OPGs based on SFA-popliteal procedures (n = 21,377) for intermittent claudication and critical limb ischemia (CLI). OPGs included 1-year rates for target lesion revascularization (TLR), major amputation, and 1 and 4-year survival rates. OPGs were calculated for the SFA and popliteal arteries and stratified by four treatments: angioplasty alone (percutaneous transluminal angioplasty [PTA]), self-expanding stenting, atherectomy, and any treatment type. Outcomes were illustrated by unadjusted Kaplan-Meier analyses. RESULTS: Cohorts included PTA (n = 7505), stenting (n = 9217), atherectomy (n = 2510) and any treatment (n = 21,377). The mean age was 69 years, 58% were male, 79% were White, and 52% had CLI. The freedom from TLR OPGs at 1 year in the SFA were 80.3% (PTA), 83.2% (stenting), 83.9% (atherectomy), and 81.9% (any treatments). The freedom from TLR OPGs at 1 year in the popliteal were 81.3% (PTA), 81.3% (stenting), 80.2% (atherectomy), and 81.1% (any treatments). The freedom from major amputation OPGs at 1 year after SFA PVI were 93.4% (PTA), 95.7% (stenting), 95.1% (atherectomy), and 94.8% (any treatments). The freedom from major amputation OPG at 1 year after popliteal PVI were 90.5% (PTA), 93.7% (stenting), 91.8% (atherectomy), and 91.8%, (any treatments). The 4-year survival OPGs after SFA PVI were 76% (PTA), 80% (stenting), 82% (atherectomy), and 79% (any treatments), and for the popliteal artery were 72% (PTA), 77% (stenting), 82% (atherectomy), and 75% (any treatment). On a multivariable analysis, which included patient-level, leg-level, and lesion-level covariates, CLI was the single independent factor associated with increased TLR, amputation, and mortality. CONCLUSIONS: The Superficial Femoral Artery-Popliteal EvidencE Development OPGs define a new, contemporary benchmark for SFA-popliteal interventions using a large subset of real-world evidence to inform more efficient peripheral device clinical trial designs to support regulatory and clinical decision-making. It is appropriate to discuss proposals intended for regulatory approval with the US Food and Drug Administration to refine the OPG to match the specific trial population. The OPGs may be updated using coordinated registry networks to assess long-term real-world device performance.

Absence of Long-Term Benefit of Revascularization in Patients With Intermittent Claudication: Five-Year Results From the IRONIC Randomized Controlled Trial.

BACKGROUND: The long-term benefit of revascularization for intermittent claudication is poorly understood. The aim of this study was to investigate the long-term effectiveness and cost-effectiveness compared with a noninvasive approach. METHODS: The IRONIC trial (Invasive Revascularization or Not in Intermittent Claudication) randomized patients with mild-to-severe intermittent claudication to either revascularization + best medical therapy + structured exercise therapy (the revascularization group) or best medical therapy + structured exercise therapy (the nonrevascularization group). The health-related quality of life short form 36 questionnaire was primary outcome and disease-specific health-related quality of life (vascular quality of life questionnaire) and treadmill walking distances were secondary end points. Health-related quality of life has previously been reported superior in the revascularization group at 1- and 2-year follow-up. In this study, the 5-year results were determined. The cost-effectiveness of the treatment options was analyzed from a payer/healthcare standpoint. RESULTS: Altogether, 158 patients were randomized in a 1:1 ratio. Regarding the primary end point, no intergroup differences were observed for the short form 36 sum or domain scores from baseline to 5 years, except for the short form 36 role emotional domain score, with greater improvement in the nonrevascularization group (n=116, P=0.007). No intergroup differences were observed in the vascular quality of life questionnaire total and domain scores (n=116, NS) or in treadmill walking distances (n=91, NS). A revascularization strategy resulted in almost twice the cost per patient compared with a noninvasive treatment approach ($13 098 versus $6965, P=0.02). CONCLUSIONS: After 5 years of follow-up, a revascularization strategy had lost its early benefit and did not result in any long-term improvement in health-related quality of life or walking capacity compared to a noninvasive treatment strategy. Revascularization was not a cost-effective treatment option from a payer/healthcare point of view. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01219842.

Overuse of early peripheral vascular interventions for claudication.

OBJECTIVE: Guidelines from the Society for Vascular Surgery and the Choosing Wisely campaign recommend that peripheral vascular interventions (PVIs) be limited to claudication patients with lifestyle-limiting symptoms only after a failed trial of medical and exercise therapy. We sought to explore practice patterns and physician characteristics associated with early PVI after a new claudication diagnosis to evaluate adherence to these guidelines. METHODS: We used 100% Medicare fee-for-service claims to identify patients diagnosed with claudication for the first time between 2015 and 2017. Early PVI was defined as an aortoiliac or femoropopliteal PVI performed within 6 months of initial claudication diagnosis. A physician-level PVI utilization rate was calculated for physicians who diagnosed >10 claudication patients and performed at least one PVI (regardless of indication) during the study period. Hierarchical multivariable logistic regression was used to identify physician-level factors associated with early PVI. RESULTS: Of 194,974 patients who had a first-time diagnosis of claudication during the study period, 6286 (3.2%) underwent early PVI. Among the 5664 physicians included in the analysis, the median physician-level early PVI rate was low at 0% (range, 0%-58.3%). However, there were 320 physicians (5.6%) who had an early PVI rate ≥14% (≥2 standard deviations above the mean). After accounting for patient characteristics, a higher percentage of services delivered in ambulatory surgery center or office settings was associated with higher PVI utilization (vs 0%-22%; 23%-47%: adjusted odds ratio [aOR], 1.23; 48%-68%: aOR, 1.49; 69%-100%: aOR, 1.72; all P < .05). Other risk-adjusted physician factors independently associated with high PVI utilization included male sex (aOR, 2.04), fewer years in practice (vs ≥31 years; 11-20 years: aOR, 1.23; 21-30 years: aOR, 1.13), rural location (aOR, 1.25), and lower volume claudication practice (vs ≥30 patients diagnosed during study period; ≤17 patients: aOR, 1.30; 18-29 patients: aOR, 1.35; all P < .05). CONCLUSIONS: Outlier physicians with a high early PVI rate for patients newly diagnosed with claudication are identifiable using a claims-based practice pattern measure. Given the shared Society for Vascular Surgery and Choosing Wisely initiative goal to avoid interventions for first-line treatment of claudication, confidential data-sharing programs using national benchmarks and educational guidance may be useful to address high utilization in the management of claudication.

A low-cost, wireless near-infrared spectroscopy device detects the presence of lower extremity atherosclerosis as measured by computed tomographic angiography and characterizes walking impairment in peripheral artery disease.

BACKGROUND: Patients with peripheral artery disease (PAD) who experience intermittent claudication report a range of symptoms. Patients with symptoms other than classically described intermittent claudication may be at the highest risk for functional decline and mobility loss. Therefore, technologies allowing for characterization of PAD severity are desirable. Near-infrared spectroscopy (NIRS) allows for measurements of muscle heme oxygen saturation (StO2) during exercise. We hypothesized lower extremities affected by PAD would exhibit distinct NIRS profiles as measured by a low-cost, wireless NIRS device and that NIRS during exercise predicts walking limitation. METHODS: We recruited 40 patients with PAD and 10 control participants. All patients with PAD completed a computed tomographic angiography, 6-minute walk test, and a standardized treadmill test. Controls completed a 540-second treadmill test for comparison. StO2 measurements were continuously taken from the gastrocnemius during exercise. Variables were analyzed by Fischer's exact, χ2, Wilcoxon rank-sum, and Kruskal-Wallis tests as appropriate. Correlations were assessed by partial Spearman correlation coefficients adjusted for occlusive disease pattern. RESULTS: Patients with PAD experienced claudication onset at a median of 108 seconds with a median peak walking time of 288 seconds. The baseline StO2 was similar between PAD and control. The StO2 of PAD and control participants dropped below baseline at a median of 1 and 104 seconds of exercise, respectively (P < .0001). Patients with PAD reached minimum StO2 earlier than control participants (119 seconds vs 522 seconds, respectively; P < .001) and experienced a greater change in StO2 at 1 minute of exercise (-73.2% vs 8.3%; P < .0001) and a greater decrease at minimum exercise StO2 (-83.4% vs -16.1%; P < .0001). For patients with PAD, peak walking time, and 6-minute walking distance correlated with percent change in StO2 at 1 minute of exercise (r = -0.76 and -0.67, respectively; P < .001) and time to minimum StO2 (r = 0.79 and 0.70, respectively; P < .0001). CONCLUSIONS: In this initial evaluation of a novel, low-cost NIRS device, lower extremities affected by PAD exhibited characteristic changes in calf muscle StO2, which differentiated them from healthy controls and were strongly correlated with walking impairment. These findings confirm and expand on previous work demonstrating the potential clinical value of NIRS devices and the need for further research investigating the ability of low-cost NIRS technology to evaluate, diagnose, and monitor treatment response in PAD.

Delayed gratification and adherence to exercise among patients with claudication.

Few studies have explicitly identified factors that explain an individual's willingness to engage in community-based exercise for claudication. Identifying the unique characteristics of those inclined toward physical activity would inform interventions that encourage walking. We examined the utility of behavioral economics-related concepts in understanding walking among Veterans with claudication. Patients who received care at the Michael E. DeBakey Veterans Affairs Medical Center in Houston, Texas, were surveyed on symptom severity, behavioral economics, stress, and depression. The primary outcome was a binary variable measuring current walking for exercise and defined as walking for at least 30 minutes every day. Multivariable logistic regression models were used to identify variables, both clinically and statistically significant, at a p-value < 0.05. Between April 2017 and March 2018, we received 148 (30%) responses. A total of 35% (n = 51) of respondents indicated that they walked recreationally for exercise compared to 65% (n = 94) who did not. Characteristics that were significantly associated with walking included regularly saving money (adjusted odds ratio (aOR) = 10.7, p = 0.001), seeking complex problem-solving (aOR = 0.12, p = 0.002), and severe symptoms (aOR = 0.24, p = 0.017). Individuals describing a preference for the future rather than immediate benefit also reported currently walking for exercise. Defining the characteristics of those who exercise may help inform strategies designed to increase walking among those who do not adhere to recommendations.

Echocardiographic assessment at rest and during stress in patients with intermittent claudication.

Objective. Skeletal muscle perfusion during walking relies on complex interactions between cardiac activity and vascular control mechanisms, why cardiac dysfunction may contribute to intermittent claudication (IC) symptoms. The study aims were to describe cardiac function at rest and during stress in consecutive IC patients, to explore the relations between cardiac function parameters and treadmill performance, and to test the hypothesis that clinically silent myocardial ischemia during stress may contribute to IC limb symptomatology. Design. Patients with mild to severe IC (n = 111, mean age 67 y, 52% females, mean treadmill distance 195 m) underwent standard echocardiography, dobutamine stress echocardiography (SE) and treadmill testing. The patient cohort was separated in two groups based on treadmill performance (HIGH and LOW performance). Results. Ten patients (9%) had regional wall motion abnormalities of which three had left ventricular ejection fraction <50% at standard echocardiography. A majority had lower than expected systolic- and diastolic ventricular volumes. LOW performers had smaller diastolic left ventricular volumes and lower global peak systolic velocity during dobutamine stress. No patient demonstrated significant cardiac dysfunction during dobutamine provocation that was not also evident at standard echocardiography. Conclusions. Most IC patients were without signs of ischemic heart disease or cardiac failure. The majority had small left ventricular volumes. The hypothesis that clinically silent myocardial ischemia impairing left ventricular function during stress may contribute to IC limb symptomatology was not supported.

A multicenter randomized controlled study to evaluate whether neuromuscular electrical stimulation improves the absolute walking distance in patients with intermittent claudication compared with best available treatment.

OBJECTIVE: To assess the clinical efficacy of a neuromuscular electrical stimulation (NMES) device to improve the absolute walking distance in patients with intermittent claudication as an adjunct to the local standard care available at the study sites compared with local standard care alone. METHODS: This open, multicenter, randomized controlled trial included eight participating centers in England. Sites are equally distributed between those that provide supervised exercise therapy programs and those that do not. Patients with intermittent claudication meeting the eligibility criteria and providing consent will be randomized, depending on the center type, to either NMES and locally available standard care or standard care alone. The primary end point is change in absolute walking distance at 3 months (the end of the intervention period) by treadmill testing. Secondary outcomes include quality of life, compliance with the interventions, economic evaluation of the NMES device, and lower limb hemodynamic measures to further the understanding of underlying mechanisms. Recruitment commenced in March 2018 and will continue for a total of 15 months. The Neuromuscular Electrical Stimulation Improves the Absolute Walking Distance in Patients with Intermittent Claudication trial is funded by the UK Efficacy and Mechanism Evaluation Programme, Medical Research Council, and National Institute for Health Research partnership.

Ankle-brachial index in patients with intermittent claudication is a poor indicator of patient-centered and clinician-based evaluations of functional status.

BACKGROUND: The association between the severity of ankle-brachial index (ABI), a traditional measure of the severity of peripheral artery disease (PAD), and patients' perceptions of their health status is poorly characterized. In Patient-Centered Outcomes Related to Treatment Practices in Peripheral Artery Disease: Investigating Trajectories (PORTRAIT), a study of patients with intermittent claudication (IC), we studied the correlation of ABI values and Rutherford symptom classification with PAD-specific health status as measured by the Peripheral Artery Questionnaire (PAQ). METHODS: Among 1251 patients with new onset or exacerbation of IC enrolled at 16 sites in the United States, Netherlands, and Australia, ABI values were categorized as mild (>0.80), moderate (0.40-0.79), and severe (<0.40). Spearman rank correlation coefficients were calculated between raw ABI values and PAQ scores and between the Rutherford classification and PAQ scores. RESULTS: Mean ABI was 0.67 (standard deviation, 0.19); 24.3% had mild, 67.6% moderate, and 8.1% severe PAD. According to the Rutherford classification, 22.7% were stage 1 (mild claudication), 49.5% stage 2 (moderate claudication), and 27.8% stage 3 (severe claudication). Correlations (95% confidence interval) were found between ABI and the PAQ summary score (r = 0.09 [0.04-0.15]) and the PAQ physical limitations score (r = 0.14 [0.09-0.20]); no correlations were found between ABI and the PAQ quality of life score (r = 0.03 [-0.02 to 0.09]) and the PAQ symptoms score (r = 0.04 [-0.01 to 0.10]). With the correlations between ABI and PAQ scores, ABI explained only 0.1% to 2.1% of the variation in PAQ scores. Rutherford classification had stronger but still modest associations with PAQ scores (PAQ summary, r = -0.27 [-0.21 to -0.32]; PAQ quality of life, r = -0.21 [-0.16 to -0.27]; PAQ symptoms, r = -0.18 [-0.13 to -0.23]; PAQ physical limitations, r = -0.27 [-0.22 to -0.32]); Rutherford class explained 3.2% to 7.3% of the variation in PAQ scores. CONCLUSIONS: In a large, international cohort of patients with IC, patient-centered health status assessments are weakly associated with physicians' or hemodynamic assessments. To best measure the impact of PAD on patients' symptoms, functional capacity, and quality of life, direct assessment from patients is needed, rather than relying on physiologic or clinician-assigned assessments.

High Reintervention and Amputation Rates After Outpatient Atherectomy for Claudication.

Outpatient use of atherectomy for peripheral arterial disease has grown rapidly and outcomes are poorly understood. We analyzed outcomes of atherectomy done for claudication, comparing office and hospital outpatient settings. Analysis of Medicare Part B claims data was performed for incident femoral-popliteal or tibial-peroneal atherectomy from 2012 to 2014. Longitudinal analysis assessed services 18 months before, during, and up to 18 months after the incident peripheral vascular intervention (PVI). Differences between office-based and hospital outpatient-based settings were assessed using χ2 and Fisher exact tests. Comparing procedure settings, significant differences in race (femoral-popliteal: P = .04, tibial-peroneal: P = .001), chronic renal failure (femoral-popliteal: P = .002), and hypertension (femoral-popliteal: P = .01, tibial-peroneal: P = .006) were found. Nine hundred twenty-four patients undergoing femoral-popliteal atherectomy were analyzed (262 office based, 662 hospital outpatient based); 42.7% of office-based and 36.9% of hospital outpatient-based femoral-popliteal atherectomy patients had repeat PVI within 18 months ( P = .10). Major amputation was performed in 2.3% and 3.2% of patients in office and hospital outpatient settings, respectively ( P = .47). Four hundred twenty-three patients undergoing tibial-peroneal atherectomy were analyzed (202 office based, 221 hospital outpatient based); 46.5% of office-based and 38.9% of hospital outpatient-based tibial-peroneal atherectomy patients had repeat PVI within 1 year ( P = .11). Major amputation was performed in 5.0% and 8.1% of patients in office and hospital outpatient settings, respectively ( P = .19). Our study demonstrates higher than expected rates of major amputation for patients undergoing peripheral arterial atherectomy with regard to previously reported rates. Further studies may be required to prove the efficacy and safety of atherectomy for occlusive disease in the femoral-popliteal and tibial-peroneal segments to ensure outcomes are not worse than the natural history of medically managed claudicants.

Directional Atherectomy Is Associated with Better Long-Term Efficiency Compared with Angioplasty for Common Femoral Artery Occlusive Disease in Rutherford 2-4 Patients.

BACKGROUND: Despite increased interest in treating common femoral artery (CFA) with endovascular technology, there are little data regarding the long-term outcomes of different endovascular treatment modalities. We report the results after endovascular therapy of symptomatic obstructions of the CFA in a single center. METHODS: We retrospectively reviewed the records of consecutive patients with eligible CFA lesions who were treated with endovascular methods between 2011 and 2013. The preoperative demographic operative details and postoperative outcomes were compared and statistically analyzed. RESULTS: Ninety patients with CFA lesions were treated, and 76 (84.4%) completed a follow-up. Claudication was present in 62 of 76 (81.6%) patients, and stenosis was present in 60 of 76 (78.9%) patients. Angioplasty was performed in 45 patients, and atherectomy was performed in 31 patients. There was no significant difference in the preoperative demographic data, procedure time, contrast administration, or length of hospital stay between the 2 groups. In-hospital treatment costs were significantly higher in the atherectomy group (69,822 RenMinBi Yuan vs. 49,078 RenMinBi Yuan; P = 0.043). During the 4-year primary patency, for whole group or bifurcated/claudicant subgroup, all patients within the atherectomy group were significantly better than those in the angioplasty group. CONCLUSIONS: Atherectomy may be a better alternative to angioplasty for CFA atherosclerotic obstructions lesions. Compared with angioplasty, atherectomy seems to have better results in bifurcated lesions or claudicant patients. In diabetic patients, no superiority was found on either patency or improvement in walking distance.

PORTRAIT (Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories): Overview of Design and Rationale of an International Prospective Peripheral Arterial Disease Study.

BACKGROUND: Health status outcomes, including symptoms, functional status, and quality of life, are critically important outcomes from patients' perspectives. The PORTRAIT study (Patient-Centered Outcomes Related to Treatment Practices in Peripheral Arterial Disease: Investigating Trajectories) was designed to prospectively define health status outcomes and examine associations between patients' characteristics and care to these outcomes among those presenting with new-onset or worsened claudication. METHODS AND RESULTS: PORTRAIT screened 3637 patients with an abnormal ankle-brachial index and new, or worsened, claudication symptoms from 16 peripheral arterial disease (PAD) specialty clinics in the United States, the Netherlands, and Australia between June 2, 2011, and December 3, 2015. Of the 1608 eligible patients, 1275 (79%) were enrolled. Before treatment, patients were interviewed to obtain their demographics, PAD symptoms and health status, psychosocial characteristics, preferences for shared decision-making, socioeconomic, and cardiovascular risk factors. Patients' medical history, comorbidities, and PAD diagnostic information were abstracted from patients' medical records. Serial information about patients' health status, psychosocial, and lifestyle factors was collected at 3, 6, and 12 months by a core laboratory. Follow-up rates ranged from 84.2% to 91%. Clinical follow-up for PAD-related hospitalizations and major cardiovascular events is ongoing. CONCLUSIONS: PORTRAIT systematically collected serial PAD-specific health status data as a foundation for risk stratification, comparative effectiveness studies, and clinicians' adherence to quality-based performance measures. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01419080.

Association between health status and sociodemographic, clinical and treatment disparities in the Patient-centered Outcomes Related to TReatment Practices in Peripheral Arterial Disease: Investigating Trajectories (PORTRAIT) registry.

Patients with peripheral artery disease (PAD) and intermittent claudication (IC) have impaired functional status and quality of life. However, little is known about which factors are associated with poorer health status at the time of initial presentation for PAD specialty care. Characterization of such features might provide insight into disparities that impact health status in this population. A total of 1258 patients from the United States, the Netherlands and Australia with new or worsened IC were enrolled at their first PAD specialty care visit between June 2011 and December 2015. The mean Peripheral Artery Questionnaire (PAQ) Summary Score (range 0-100), a disease-specific health status measure, was 49.2 ± 21.9. Hierarchical, multivariable linear regression was used to relate patient characteristics to baseline PAQ. Patient characteristics independently associated with poorer health status were age ( p < 0.001), female sex ( p < 0.001), not being married ( p = 0.02), economic burden (moderate/severe vs none, moderate/severe vs some; p = 0.03), difficulty getting care (moderate/severe vs none, moderate/severe vs some; p < 0.001), chronic lung disease ( p = 0.02), back pain ( p < 0.001), bilateral vs unilateral PAD ( p = 0.02), intermittent claudication severity (moderate vs mild, severe vs mild, p < 0.001), and lack of prior participation in an exercise program ( p = 0.005). Disparities in both vascular and non-vascular factors were associated with patients' health status at the time of presentation and should be addressed by all who care for patients with vascular disease.

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.

Hemodynamic Assessment Before and After Endovascular Therapy for Critical Limb Ischemia and Association With Clinical Outcomes.

OBJECTIVES: This study sought to determine the relationship between change in ankle-brachial index (ABI) and toe-brachial index (TBI) and outcomes following revascularization of critical limb ischemia (CLI). BACKGROUND: An increase in ABI of 0.15 after revascularization for peripheral artery disease with claudication is considered significant. However, the utility of using change in ABI or TBI to predict outcomes in patients with CLI is unproven. METHODS: This was an observational study of 218 patients with Rutherford class V or VI CLI that underwent endovascular therapy. Receiver-operating characteristic curve analysis determined cutpoints in post-procedure ABI and TBI, as well as change in these values for endpoints of wound healing, major adverse limb events (MALE), and repeat revascularization. RESULTS: After multivariable Cox proportional hazards analysis adjusting for age, diabetes, glomerular filtration rate, smoking, Rutherford class, and baseline ABI or TBI, neither static post-procedure ABI nor post-procedure TBI were associated with wound healing (hazard ratio [HR]: 1.21; 95% confidence interval [CI]: 0.77 to 1.89; p = 0.40; HR: 1.49; 95% CI: 0.98 to 2.27; p = 0.065, respectively). However, change in ABI ≥0.23 was independently associated with wound healing (HR: 1.87; 95% CI: 1.12 to 3.15; p = 0.018) and less repeat revascularization (HR: 0.40; 95% CI: 0.19 to 0.84; p = 0.015), but not MALE. Increase in TBI ≥0.21 was independently associated with wound healing (HR: 1.63; 95% CI: 1.02 to 2.59; p = 0.039), and reduced MALE (HR: 0.27; 95% CI: 0.09 to 0.77; p = 0.014), but not repeat revascularization. CONCLUSIONS: A change in ABI and TBI from pre-procedural values provides prognostic value in determining which patients may have wound healing and reduced MALE.

Exercise training for intermittent claudication.

OBJECTIVE: The objective of this study was to provide an overview of evidence regarding exercise therapies for patients with lower extremity peripheral artery disease (PAD). METHODS: This manuscript summarizes the content of a lecture delivered as part of the 2016 Crawford Critical Issues Symposium. RESULTS: Multiple randomized clinical trials demonstrate that supervised treadmill exercise significantly improves treadmill walking performance in people with PAD and intermittent claudication symptoms. A meta-analysis of 25 randomized trials demonstrated a 180-meter increase in treadmill walking distance in response to supervised exercise interventions compared with a nonexercising control group. Supervised treadmill exercise has been inaccessible to many patients with PAD because of lack of medical insurance coverage. However, in 2017, the Centers for Medicare and Medicaid Services issued a decision memorandum to support health insurance coverage of 12 weeks of supervised treadmill exercise for patients with walking impairment due to PAD. Recent evidence also supports home-based walking exercise to improve walking performance in people with PAD. Effective home-exercise programs incorporate behavioral change interventions such as a remote coach, goal setting, and self-monitoring. Supervised treadmill exercise programs preferentially improve treadmill walking performance, whereas home-based walking exercise programs preferentially improve corridor walking, such as the 6-minute walk test. Clinical trial evidence also supports arm or leg ergometry exercise to improve walking endurance in people with PAD. Treadmill walking exercise appears superior to resistance training alone for improving walking endurance. CONCLUSIONS: Supervised treadmill exercise significantly improves treadmill walking performance in people with PAD by approximately 180 meters compared with no exercise. Recent evidence suggests that home-based exercise is also effective and preferentially improves over-ground walking performance, such as the 6-minute walk test.

Assessment of Minimum Important Difference and Substantial Clinical Benefit with the Vascular Quality of Life Questionnaire-6 when Evaluating Revascularisation Procedures in Peripheral Arterial Disease.

OBJECTIVES: Patient reported outcomes are increasingly used to assess outcomes after peripheral arterial disease (PAD) interventions. VascuQoL-6 (VQ-6) is a PAD specific health-related quality of life (HRQoL) instrument for routine clinical practice and clinical research. This study assessed the minimum important difference for the VQ-6 and determined thresholds for the minimum important difference and substantial clinical benefit following PAD revascularisation. MATERIALS AND METHODS: This was a population-based observational cohort study. VQ-6 data from the Swedvasc Registry (January 2014 to September 2016) was analysed for revascularised PAD patients. The minimum important difference was determined using a combination of a distribution based and an anchor-based method, while receiver operating characteristic curve analysis (ROC) was used to determine optimal thresholds for a substantial clinical benefit following revascularisation. RESULTS: A total of 3194 revascularised PAD patients with complete VQ-6 baseline recordings (intermittent claudication (IC) n = 1622 and critical limb ischaemia (CLI) n = 1572) were studied, of which 2996 had complete VQ-6 recordings 30 days and 1092 a year after the vascular intervention. The minimum important difference 1 year after revascularisation for IC patients ranged from 1.7 to 2.2 scale steps, depending on the method of analysis. Among CLI patients, the minimum important difference after 1 year was 1.9 scale steps. ROC analyses demonstrated that the VQ-6 discriminative properties for a substantial clinical benefit was excellent for IC patients (area under curve (AUC) 0.87, sensitivity 0.81, specificity 0.76) and acceptable in CLI (AUC 0.736, sensitivity 0.63, specificity 0.72). An optimal VQ-6 threshold for a substantial clinical benefit was determined at 3.5 scale steps among IC patients and 4.5 in CLI patients. CONCLUSIONS: The suggested thresholds for minimum important difference and substantial clinical benefit could be used when evaluating VQ-6 outcomes following different interventions in PAD and in the design of clinical trials.