The Reliability of Walking Tests in People with Claudication

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

INTRODUCTION

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

METHODS AND ANALYSIS

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

ETHICS AND DISSEMINATION

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

Normative reference values, determinants and regression equations for the incremental shuttle walk test (ISWT) in healthy Asian population aged 21 to 80 years

BACKGROUND

The validated Incremental Shuttle Walk Test (ISWT) is widely used for evaluating maximal exercise capacity, with the distance-walked (IWSD) as the primary outcome. However, there are no normative reference values (NRV) and reference equations to predict ISWD for the Singaporean population.

OBJECTIVES

This study aims to establish the NRV and reference equations for ISWD in healthy Singaporeans aged 21 to 80 and investigate the determining variables during ISWT.

METHODS

This cross-sectional study recruited community-dwelling healthy subjects aged 21-80 from the community via convenience sampling. Each subject completed two trials of the ISWT according to the standard protocol. Variables measured during the trials included ISWD, pre-and post-test heart rate (HR), oxygen saturation, blood pressure (BP), modified Borg's dyspnoea score and Borg's rate of perceived exertion (RPE).

RESULTS

199 healthy Singaporean (females = 114, males = 85) participated in the study. The overall median ISWD was 660.0 metres (m) [interquartile range (IQR):440.0-850.0]. The age-stratified mean ISWD ranged from 430.0 m (IQR:350.0-450.0) (aged 60-80) to 480.0 m (IQR:438.0-650.0) (aged 40-59) to 780.0 m (IQR:670.0-960.0) (aged 21-39). Gender, age, weight, height and HR change (highest post-test HR minus pre-test HR) were the most significant variables (p < 0.001). IWSD (m) = 651.4(Height, m) +89.7(Gender, male = 1; female = 0) -6.31(Age, years) -3.61(Weight, kilograms) +2.54(HR change, beats per minute); R2 = 0.741. Previously published ISWT reference equations cannot accurately predict the ISWD in the Singaporean population.

CONCLUSIONS

This study investigated the ISWD NRV and established reference equations for healthy Singaporeans aged 21-80. The information would be beneficial in setting performance benchmarks to guide physical assessment, intervention and rehabilitation.

Chinese (Mandarin) translation of the incremental shuttle walk test and its validity and reliability: A cross-sectional study

BACKGROUND/PURPOSE

To date, there are no published validated Chinese versions of the incremental shuttle walk test (ISWT) instructions despite its wide clinical applications. Translation of the Chinese ISWT instruction is done in an ad-hoc manner within the Chinese-speaking populations, affecting the test's reliability and validity since translation can differ significantly between individuals. This warrants the need for psychometric testing of such translation.

OBJECTIVES

To develop a Chinese (Mandarin) version of the ISWT instructions (ISWT-CHN) that is conceptually equivalent to the original English version (ISWT-ENG) and establish its reliability and validity.

METHODS

Forward and backward translations from the ISWT-ENG were done to generate the ISWT-CHN. Face and content validity was determined during the translation process. Intra-rater and inter-rater reliability of the ISWT-CHN, construct and criterion validity were established by analysing the ISWT and the gold standard cardiopulmonary exercise test results.

RESULTS

The Item-Content validity index (I-CVI), Scale-level-Content validity index (S-CVI), and content validity ratio (CVR) of the ISWT-CHN were 1.0. Intra-class Correlation Coefficient (ICC) for inter-rater reliability between two raters were excellent (ICC = 0 . 99 , 95% CI 0.97-1.0, p < 0 . 001 ; SEM = 0 . 85 m, MDC = 2 . 35 m). The intra-rater reliability of both Raters A (ICC = 0 . 92 , 95% CI 0.53-0.98, p = 0 . 003 ; SEM = 35 m, MDC = 97 m) and B (ICC = 0 . 90 , 95% CI 0.76-0.96, p < 0 . 001 ; SEM = 32 m, MDC = 88 m) were good. In a sample of 32 healthy participants, both ISWT-CHN and ISWT-ENG instruction results showed low-positive correlations with the VO2 max determined from the cardiopulmonary exercise test (r = 0.439, p < 0 . 001 ; r = 0 . 448 , p < 0 . 001 ). There is a very high correlation between ISWT-ENG and ISWT-CHN results with no statistically significant differences (r = 0 . 967 , p < 0 . 001 ). The construct and criterion validity of the ISWT-CHN were established.

CONCLUSION

This study developed the ISWT-CHN and showed that it is a valid and reliable measure conceptually comparable to the ISWT-ENG. It will benefit the determination of functional exercise capacity in Chinese-speaking populations.

KEY MESSAGES

•This study is aimed to develop a Chinese (Mandarin) version of the ISWT instructions.•The ISWT Chinese translation is valid and reliable that is conceptually comparable to the original English instruction.•The translated ISWT-Chinese instruction will enable the use of ISWT among the Chinese-speaking populations.

Rehabilitation of patients with peripheral arterial disease

Vascular rehabilitation is an essential and effective treatment of peripheral arterial obstructive disease (PAOD). It is recommended in the first line by the European and American scientific societies. The rehabilitation to the walk remains the basic treatment of the arteriopathy of the lower limbs. Different walking protocols can be proposed. For similar effectiveness, vascular rehabilitation consists of an outpatient or specialized institution management program based on a comprehensive approach involving all or many of the following techniques: relaxation, active analytical exercises, gait rehabilitation, exercise re-entry, physical activities adapted to the patient's daily life and illness, respiratory physiotherapy, therapeutic education of the patient, smoking cessation aid. Vascular rehabilitation of arteritis requires a variety of skills but still faces a clear lack of suitable structures; it remains poorly prescribed and poorly known by usual prescribers (general practitioner, vascular surgeon).

The reliability and validity of the 30-seconds sit-to-stand test and its capacity for assessment of the functional status of hemodialysis patients

PURPOSE

To investigate the validity of the 30-seconds sit-to-stand test (STS-30) and its reliability in hemodialysis patients.

METHODS

Patients receiving hemodialysis treatment three times a week for at least six months were evaluated using STS-30, Incremental Shuttle Walking Test, and health-related quality of life by KDQOL-SF questionnaire. The data obtained from the Incremental Shuttle Walking Test were divided into tertiles, and the STS-30 results were compared among tertiles. The accuracy of the STS-30 to identify low exercise capacity was evaluated. A second STS-30 was performed after 6 to 8-weeks for the reliability analyses using Intraclass Correlation Coefficient (ICC). Minimal detectable change scores were calculated.

RESULTS

Sixty-three individuals (66.7% men) aged 48.3 years (95%CI 44.6-51.9) were evaluated. There were significant correlations between STS-30, exercise capacity (r = 0.72), and physical domains of health-related quality of life (0.30 ≤ r ≤ 0.51). Tertile 1 of the Incremental Shuttle Walking Test was different from tertiles 2 and 3 for STS-30 [difference of 3.4 repetitions (95%CI 1.5-5.4) and 4.7 repetitions (95%CI 2.8-6.7), respectively]. The value of 12 repetitions was the cut-off points for stratification of individuals with low exercise capacity. The STS-30 had a high test-retest reliability (ICC = 0.93) and the minimal detectable change was 2.1 repetitions.

CONCLUSION

The STS-30 is a reliable test, associated with exercise capacity and physical domains of health-related quality of life. Thus, is a valid method for functional evaluation in hemodialysis patients.

Efficacy of inspiratory muscle training on inspiratory muscle function, functional capacity, and quality of life in patients with asthma: A randomized controlled trial

OBJECTIVE

To evaluate the efficacy of an inspiratory muscle training protocol on inspiratory muscle function, functional capacity, and quality of life in patients with asthma.

DESIGN

A single-blind, randomized controlled clinical trial.

SETTING

Community-based.

SUBJECTS

Patients with asthma, aged between 20 and 70 years old, non-smokers.

INTERVENTIONS

Participants were randomized into two groups: inspiratory muscle training group performed inspiratory muscle training 5 days a week for 8 weeks, consisting of six sets of 30 breaths per day with a training load ⩾50% of maximal inspiratory pressure, plus an educational program; the control group only received the educational program.

MAIN MEASUREMENTS

Maximal inspiratory pressure, inspiratory muscle endurance, and the distance performed on the incremental shuttle walking test were assessed pre-intervention, post-intervention and at follow-up (3 months after the end of the intervention). The asthma quality of life questionnaire was applied pre and post-intervention.

RESULTS

Data from 39 participants were analyzed. Maximal inspiratory pressure in percentage of predicted and endurance test duration were significantly higher post-intervention in the inspiratory muscle training group (∆ post-pre: 50.8% vs 7.3% of predicted - P < 0.001 and ∆ post-pre: 207.9 seconds vs 2.7 seconds - P < 0.001, respectively). There was no significant difference in the incremental shuttle walking distance between groups (∆ post-pre: 30.9 m vs -8.1 m, P = 0.165). Quality of life was perceived as significantly better, without a difference between groups (P > 0.05).

CONCLUSIONS

About 8 weeks of inspiratory muscle training in patients with controlled asthma significantly increased inspiratory muscle strength and endurance.

Reliability and responsiveness of incremental shuttle walk test to estimate exercise capacity in patients with pulmonary arterial hypertension

The purpose of the present study was to evaluate the reliability and responsiveness of the incremental shuttle walk test (ISWT) to estimate exercise capacity in patients with pulmonary arterial hypertension (PAH). This was a cross-sectional longitudinal study performed on stable PAH patients (n=30, mean age ± standard deviation, 60±13.6 years) with World Health Organization functional class II & III. Reliability was assessed by comparing the distance covered between ISWT-1 (initial) and ISWT-2 (retest). Responsiveness was determined by comparing the distance covered in the ISWT-3 post pulmonary rehabilitation (PR) to the ISWT-1. The distance covered between ISWT-1 (177±87.85 m) and ISWT-2 (191.67±96.39 m) was not statistically significant. The result of the relative reliability has shown to be excellent with an intraclass correlation coefficient (ICC2,1= 0.98, 95%CI = 0.95-0.99). Absolute reliability was evaluated through the standard error of the measurement and minimal detectable change at a 95% confidence interval (MDC95) were 12.29 and 33.9 m, respectively. Bland Altman plot showed good agreement between the two ISWTs. Following PR, the effect size (ES=0.78) and standardised response mean (SRM=1.50) were moderate and large respectively. ISWT is considered to be a reliable and responsive measure to estimate exercise capacity in patients with PAH. The ISWT may be considered a suitable alternative tool over a 6-min walk test and in the absence of equipment availability or expertise for conducting cardiopulmonary exercise test for the assessment of exercise capacity in these patients.

Reliability, Validity, and Responsiveness of the Incremental Shuttle Walk Test in Patients With Interstitial Lung Disease

PURPOSE

To determine the reliability, validity, and responsiveness of the incremental shuttle walk test (ISWT) in patients with interstitial lung disease (ILD).

METHODS

This was a cross-sectional longitudinal study. Patients (n = 27, 10 males; mean age ± SD, 61 ± 9.8 y) with ILD of any etiology, who participated in an outpatient pulmonary rehabilitation (PR) program, were recruited. Reliability was determined by comparing the distance covered in meters between the ISWT-1 and the ISWT-2. Validity was assessed by correlating the distance covered in the ISWT-1, with the maximum oxygen consumption ((Equation is included in full-text article.)O2max) obtained through cardiopulmonary exercise testing and distance covered during the 6-min walk test (6MWT). Responsiveness was assessed by comparing the distance covered in the ISWT-3, undertaken after the completion of PR, to the ISWT-1.

RESULTS

The distance covered was equivalent between the ISWT-1 (216.7 ± 64.9 m) and the ISWT-2 (220.7 ± 67.3 m), with an excellent intraclass correlation coefficient (ICC2,1 = 0.91; 95% CI, 0.81-0.95). The standard error of measurement and minimal detectable change at the 95% CI (MDC95) values for the ISWT were 19.5 m and 53.9m, respectively. There were significant correlations between the distance covered on the ISWT and (Equation is included in full-text article.)O2max (r = 0.79, P < .0001) and the distance covered on the 6MWT (r = 0.76, P < .0001). Following PR, the change in the ISWT distance showed large effect size (ES = 0.85) and standardized response mean (SRM = 1.58).

CONCLUSIONS

The ISWT is a reliable, valid, and responsive measure of estimated functional capacity in patients with ILD.

Effects of modified aerobic training on muscle metabolism in individuals with peripheral arterial disease: a randomized clinical trial

The primary objective of this study was to compare the effects on muscle metabolism of two types of aerobic training, with and without a load on the lower limbs, in adults with peripheral arterial disease (PAD). A simple blind randomized clinical trial was conducted using two groups: conventional aerobic (CG) and modified aerobic with a load on the lower limbs (MG). Both groups underwent training by walking three times a week over a 12-week period. The ratings of muscle metabolism were determined after a treadmill test with constant velocity and inclination concomitant with the use of near infrared spectroscopy (NIRS). Altogether 40 individuals with PAD (CG = 65.45 ± 10.60 and MG = 63.10 ± 10.54) were included in the study. After the intervention, in both groups, there was a reduction in the relative time to recovery (p = 0.002), an improvement in the re-oxygenation rate (p = 0.017), an increased time of resistance after reaching the lowest muscle oxygen saturation (StO₂) (p < 0.001), an increase in the distance walked (p < 0.001), and an improvement of the walking economy relative to StO₂ (p < 0.001). After 12 weeks of training, an improvement in the deoxygenation rate was observed in both groups (p = 0.002), but with a greater magnitude in the CG (p = 0.017). Only the CG presented an increase in time to reach the lowest StO₂ on the treadmill after the intervention (p = 0.010). The traditional aerobic training was superior to the modified training in relation to the improvement of muscle metabolism in patients with PAD.

Peripheral arterial disease screening and diagnostic practice: A scoping review

Early reliable, valid screening, diagnosis, and treatment improve peripheral arterial disease outcomes, yet screening and diagnostic practices vary across settings and specialties. A scoping literature review described reliability and validity of peripheral ischaemia diagnosis or screening tools. Clinical studies in the PUBMED database January 1, 1970, to August 13, 2018, were reviewed summarising ranges of reliability and validity of peripheral ischaemia diagnostic and screening tools for patients with non-neuropathic lower leg ischaemia. Peripheral ischaemia screening and diagnostic practices varied in parameters measured such as timing, frequency, setting, ordering clinicians, degree of invasiveness, costs, definitions, and cut-off points informing clinical and referral decisions. Traditional ankle/brachial systolic blood pressure index <0.9 was a reliable, valid lower leg ischaemia screening test to trigger specialist referral for detailed diagnosis. For patients with advanced peripheral ischaemia or calcified arteries, toe-brachial index, claudication, or invasive angiographic imaging techniques that can have complications were reliable, valid screening, and diagnostic tools to inform management decisions. Ankle/brachial index testing is sufficiently reliable and valid for use during routine examinations to improve timing and consistency of peripheral ischaemia screening, triggering prompt specialist referral for more reliable, accurate Doppler, or other diagnosis to inform treatment decisions.

Influence of Mild Peripheral Arterial Obstructive Disease in the Functional Capacity

AbstractThe peripheral arterial obstructive disease (PAOD) is a chronic illnes that has as main symptom intermittent claudication and causes a progressive functional impairment of the patient. The literature is still inconclusive when it addresses the relationship among functional capacity, endurance, muscle contraction speed, and degree of blood flow impairment in patients with PAOD. The objective of this study was to evaluate the physical fitness individuals with bilateral PAOD, claudication and ankle-brachial index between 0.8 and 0.9, to verify the impact of the disease in this outcome and to analyze the association among the tests. Forty individuals, with mean age 56 years were divided in: group PAOD (n=20) and control group (n=20) were subjected to the following tests: Five-Times-Sit-to-Stand Test (FTSST), Heel-rise test (HRT), test of gait speed usual (UV) and maximum (MV), shuttle walking test (SWT). There was a significant difference among the variables obtained through HRT, UV, MV and SWT, showing a worse performance of the group with PAOD compared to the control. The FTSST test showed no differences among the groups. Analyzing the whole sample, the presence of PAOD is an indicator of poor performance in TDBP. This study suggests that people with mild PAOD present reduced performance in functional endurance tests of the lower limbs and that there is a direct relationship between walking speed and patency of local arterial flow, demonstrating in an unprecedented way the need for evaluation of this public, considering the possibility of initial identification of the symptoms and giving greater efficiency in the therapeutic planning of maintenance of the functionality.Keywords: Physical Fitness. Intermittent Claudication. Peripheral Vascular Diseases.ResumoA doença arterial obstrutiva periférica (DAOP) é uma doença crônica que tem como sintoma principal a claudicação intermitente e causa um progressivo comprometimento funcional do paciente. A literatura ainda é inconclusiva quando aborda a relação entre a capacidade funcional, endurance, velocidade de contração muscular e grau de comprometimento de fluxo sanguíneo em pacientes com DAOP. O objetivo deste estudo foi avaliar a aptidão física de indivíduos com DAOP bilateral, claudicantes e Índice tornozelo-braço entre 0,8 e 0,9, verificar o impacto da doença neste desfecho e analisar a associação entre os testes. Quarenta indivíduos, com faixa etária média de 56 anos, divididos em grupo DAOP (n=20) e grupo controle (n=20), foram submetidos aos testes: Teste senta-levanta (TSL), teste ponta de pé (TPP), testes de velocidade usual (VU) e máxima (VM), teste de deslocamento bidirecional progressivo (TDBP). Houve diferença significativa entre as variáveis do TPP, VU, VM e TDBP, mostrando pior performance do grupo com DAOP comparado ao controle. O teste TSL não apresentou diferença entre os grupos. Analisando os grupos em conjunto a presença de DAOP foi indicadora de pior desempenho no TDBP. Este estudo sugere que pacientes com DAOP leve apresentam redução da performance nos testes funcionais de endurance dos membros inferiores e que existe uma relação direta entre a velocidade da marcha e a patência do fluxo arterial local, demonstrando de forma inédita, a necessidade de avaliação deste público, considerando a possibilidade de identificação inicial dos sintomas e conferindo maior eficiência no planejamento terapêutico de manutenção da funcionalidade.Palavras-chave: Aptidão Física. Claudicação Intermitente. Doenças Vasculares Periféricas.

Effects of the inspiratory muscle training and aerobic training on respiratory and functional parameters, inflammatory biomarkers, redox status and quality of life in hemodialysis patients: A randomized clinical trial

Objective

Evaluate and compare the isolated and combined effects of Inspiratory Muscle Training (IMT) and Aerobic Training (AT) on respiratory and functional parameters, inflamatory biomarkers, redox status and health-related quality of life (HRQoL) in hemodialysis patients.

Methods

A randomised controlled trial with factorial allocation and intention-to-treat analysis was performed in hemodialysis patients. Volunteers were randomly assigned to performe 8-weeks of IMT at 50% of maximal inspiratory pressure (MIP), low intensity AT or combined training (CT). Before the interventions, all the volunteers went 8-weeks through a control period (without training). Measures are taken at baseline, 8-week (after control period) and 16-week (after the interventions). Primary outcomes were functional capacity (incremental shuttle walk test), MIP and lower limbs strength (Sit-to-Stand test of 30 seconds). Plasma levels of interleukin-6 (IL-6), soluble tumor necrosis factor receptor 1 (sTNFR1) and 2 (sTNFR2), adiponectin, resistin and leptin, redox status parameters and HRQoL (KDQOL-SF questionnaire) were the scondary outcomes. Data analyses were performed by two-way repeated measurements ANOVA.

Results

37 hemodialysis patients aged 48.2 years old (IC95% 43.2–54.7) were randomized. Increase of MIP, functional capacity, lower limbs strength and resistin levels, and reduction of sTNFR2 levels in 16-week, compared to baseline and 8-week, were observed in all the groups (p<0.001). IMT improved functional capacity, MIP and lower limbs strength in 96.7m (IC95% 5.6–189.9), 34.5cmH₂O (IC95% 22.4–46.7) and 2.2repetitions (IC95% 1.1–3.2) respectively. Increase in resistin leves and reduction in sTNFR2 leves after IMT was 0.8ng/dL (IC95% 0.5–1.1) and 0.8ng/dL (IC95% 0.3–1.3), respectively, without between-group differences. Compared to baseline and 8-week, adiponectin levels (p<0.001) and fatigue domain of the HRQoL (p<0.05) increased in 16-week only in CT.

Conclusion

IMT, AT and CT improved functional parameters and modulated inflammatory biomarkers, in addition, IMT provoked a similar response to low intensity AT in hemodialysis patients.

Trial registration

Registro Brasileiro de Ensaios clínicos RBR-4hv9rs.

Evaluation of the Glittre-ADL test as an instrument for classifying functional capacity of individuals with cardiovascular diseases

•

Conventional cardiovascular tests exclusively evaluate lower limb function.

•

The functional evaluation should include upper limb activities.

•

The Glittre-ADL test has the potential to be used in cardiovascular evaluation.

•

Glittre-ADL test can discriminate functional classes of individuals with CVD.

Background

The assessment of functional capacity in individuals with cardiovascular disease is closely related to lower limb function. The Glittre-ADL test is a global test to evaluate this patients.

Objective

We aimed to verify whether the Glittre-ADL test discriminates functional status while evaluating individuals with cardiovascular disease.

Methods

A total of 42 participants were evaluated using the Glittre-ADL test Incremental Shuttle Walking Test (shuttle test), Human Activity Profile, and Duke Activity Status Index. Data from the shuttle test, Human Activity Profile, and DASI were divided into tertiles for statistical analysis. The time required to complete the Glittre-ADL test was compared among tertiles of the shuttle test, Duke Activity Status Index and Human Activity Profile using analysis of variance.

Results

There were significant differences between the tertiles of the shuttle test. Tertile 1 was different from tertiles 2 (mean difference, 47.63; 95% CI, 19.86–75.39) and 3 (mean difference, 67.15; 95% CI, 41.25–93.05). For the Duke Activity Status Index there were significant between-group differences. Tertile 1 was different from tertiles 2 (mean difference, 42.45; 95% CI, 8.82–76.09) and 3 (mean difference, 43.56; 95% CI, 13.68–73.44). For the Human Activity Profile there were significant between-group differences. Tertile 3 was different from tertiles 1 (mean difference, 51.46; 95% CI, 21.27–81.64) and 2 (mean difference, 33.01; 95% CI, 3.52–62.51).

Conclusion

The Glittre-ADL test is able to discriminate the functional status in individuals with cardiovascular disease, most of whom have hypertension. The Glittre-ADL test was sensitive to discriminate more functionally affected individuals.

Avaliação da saturação tecidual de oxigênio durante o sintoma claudicante em pacientes com doença arterial periférica

Resumo Contexto O relato de sintoma claudicante em pacientes com doença arterial periférica é utilizado como modulador da intensidade de exercício físico para o tratamento clínico, entretanto os valores de oxigenação tecidual nesse momento são desconhecidos. Objetivo Descrever o suprimento tecidual de oxigênio por meio da espectroscopia de luz próxima ao infravermelho ou Near-Infrared Spectroscopy (NIRS) nos momentos em que o paciente relata sintoma claudicante inicial e máximo em testes de exercício. Métodos Nove pacientes, oito homens com 65,63 ± 6,02 anos de idade, previamente diagnosticados com doença arterial periférica, realizaram teste de exercício de carga constante e de carga incremental com monitorização do nível de oxigenação tecidual através da NIRS. As saturações de oxigênio obtidas no momento em que o paciente relata sintoma claudicante inicial e no momento em que relata sintoma claudicante máximo foram comparadas com os valores de saturação da manobra de oclusão arterial por meio do intervalo de confiança de 95% da diferença. Resultados Verificou-se que os valores de saturação nos momentos de sintoma claudicante inicial e máximo são estatisticamente distintos quando comparados àqueles obtidos na manobra de oclusão arterial, entretanto, através da análise percentual do quão distante esses valores encontram-se é possível observar que, do ponto de vista clínico, eles estão próximos. Conclusões A saturação no momento em que o paciente relata sintomas claudicantes inicial e máximo é bastante próxima do valor de saturação no momento de oclusão e do ponto de vista clínico o relato subjetivo de sintoma do paciente é adequado como parâmetro para a prescrição do exercício físico.

Comparison of two walk tests in determining the claudication distance in patients suffering from peripheral arterial occlusive disease

BACKGROUND

The purpose of this study was to compare the six-minute walk test (6MWT) and the incremental shuttle walk test (ISWT) in terms of the initial onset of pain (IOP), maximal claudicating pain (MCP), maximum walking distance (MWD), initial ankle brachial index (IABI), post ankle brachial index (PABI), and difference in ankle brachial index (DFABI), as well as to correlate changes in IOP and MWD, MCP and MWD, IABI and MWD, PABI and MWD, and DFABI and MWD in the 6MWT and ISWT.

MATERIALS AND METHODS

Participants (n = 19, 17 men and 2 women) were randomly allocated to the 6MWT or ISWT and crossed over to the other test after 24 hours. The baseline ankle brachial index (ABI) measurements were taken using the Doppler, following which the participants performed the tests. Post-test MWD, IOP, MCP, and ABI were measured. The paired t test was used pre- and post the walk test and the Pearson correlation was used to find any relationship between the desired variables.

RESULTS

The paired t test at 95% confidence interval for IABI and PABI (P > 0.05) was insignificant for the 6MWT and ISWT. The Pearson correlation of MWD with IOP showed a fair correlation, and the correlation of MWD to MCP showed a strong correlation in ISWT.

CONCLUSION

ISWT can be of vital importance as a tool to assess the functional status of patients suffering from Peripheral Arterial Occlusive Disease (PAOD) in both the clinical and research areas, and reflects a better assessment of the functional limitation when walking with PAOD as compared to the 6MWT.

Measurement properties of the incremental shuttle walk test. a systematic review

Background: The incremental shuttle walk test (ISWT) was developed > 20 years ago and has been used to assess peak exercise capacity in a variety of chronic diseases. The aim of this systematic review is to describe the measurement properties of the ISWT in a clinical population.Methods: Of 800 articles identified by electronic and hand searches, 35 were included. Twenty-one articles included data on the validity of the ISWT, 18 on the reliability, four on the responsiveness,and four on the interpretability.Results: Most of the studies were conducted in patients with COPD (n = 13) or cardiac disease(n = 8). For criterion validity, comparisons between distance covered during the ISWT and peak oxygen consumption reported correlations ranging from 0.67 to 0.95 ( P <.01). Intraclass correlation coefficients for test-retest reliability ranged from 0.76 to 0.99. The ISWT was shown to be responsive to pulmonary rehabilitation and bronchodilator administration. The minimal clinically important difference (MCID) in patients with COPD was 48 m. Predictive equations for the distance in the ISWT are available for healthy individuals.Conclusions: The ISWT can be considered a valid and reliable test to assess maximal exercise capacity in individuals with chronic respiratory diseases. The ISWT has been shown to be responsive to pulmonary rehabilitation and bronchodilator use in individuals with COPD, cystic fibrosis,and asthma. Further studies examining responsiveness and the MCID of the ISWT in patients with conditions other than lung diseases are required for the interpretation of interventions in other populations.

[Vascular rehabilitation in patients with peripheral arterial disease]

Lower limb peripheral arterial disease (PAD) is a frequent debilitating disease associated with a high morbidity and mortality rate. The benefit of rehabilitation in PAD patients has been largely demonstrated, both for patients that undergo amputation, and for patients with claudication. In these latter patients, rehabilitation programs rely on a variety of additional techniques or tools, among which: stretching, specific muscle proprioception, walking and a variety of other physical activities, exercise or situations adapted to community life, lower limb and respiratory physiotherapy, patient's education, support for smoking cessation and healthy nutrition, social support, etc. Whether rehabilitation is performed in specialised integrated structures or performed on a home-based basis, various clinicians are involved. Despite evidence-based proof of efficacy, rehabilitation of PAD patients with claudication is still under-used.

Exercício físico, receptores β-adrenérgicos e resposta vascular

O exercício aeróbio promove efeitos benéficos na prevenção e tratamento de doenças como hipertensão arterial, aterosclerose, insuficiência venosa e doença arterial periférica. Os receptores β-adrenérgicos estão presentes em várias células. No sistema cardiovascular, promovem inotropismo e cronotropismo positivo cardíaco e relaxamento vascular. Embora os efeitos do exercício tenham sido investigados em receptores cardíacos, estudos focados nos vasos são escassos e controversos. Esta revisão abordará os efeitos do exercício físico sobre os receptores β-adrenérgicos vasculares em modelos animais e humanos e os mecanismos celulares envolvidos na resposta relaxante. Em geral, os estudos mostram resultantes conflitantes, onde observam diminuição, aumento ou nenhum efeito do exercício físico sobre a resposta relaxante. Assim, os efeitos do exercício na sensibilidade β-adrenérgica vascular merecem maior atenção, e os resultados mostram que a área de fisiopatologia vascular é um campo aberto para a descoberta de novos compostos e avanços na prática clínica.

The walking impairment questionnaire: an effective tool to assess the effect of treatment in patients with intermittent claudication

OBJECTIVE

Assessment of walking distance by treadmill testing is the most commonly used method to evaluate the effect of treatment in patients with peripheral arterial disease. However, treadmill testing is time consuming, relatively expensive, and does not adequately reflect real life functional ability. We hypothesized that the Walking Impairment Questionnaire (WIQ) could be an alternative tool to assess objective improvement in functional walking ability of patients with intermittent claudication.

METHODS

This was a validation study. It was conducted through the outpatient clinic for vascular surgery. Patients with intermittent claudication were referred for supervised exercise therapy. Treadmill testing (absolute claudication distance [ACD]), WIQ, and quality of life questionnaires (RAND-36 and EuroQol) were administered at study onset and after 3 months of supervised exercise therapy. Responsiveness was determined by mean changes in and correlation coefficients of WIQ, ACD, and quality of life questionnaires. Patients were categorized into quartiles based on the increase in ACD, which were subsequently related to change in WIQ and quality of life.

RESULTS

The mean pre- and post-treatment total WIQ scores of 91 patients were 0.45 (0.22) and 0.58 (0.22), respectively. The correlation coefficient between the change in total WIQ score and ACD was 0.331 (P = .004). A 0.1 change in total WIQ score corresponded to a change of 345 meters in ACD. Analysis of the four quartiles compared to an increase in ACD showed that a greater increase in ACD corresponded with a greater increase in WIQ score, from 0.06 to 0.25 (P = .011).

CONCLUSION

These data indicate that the WIQ is a valid tool to detect improvement or deterioration in the daily walking ability of patients with intermittent claudication. Hence, the WIQ can be used as an alternative to treadmill testing for objective assessment of functional walking ability, both in daily practice and in clinical trials.

Correlação entre o índice tornozelo-braço antes e após teste de deslocamento bidirecional progressivo

CONTEXTO: A alteração de fluxo sangüíneo observada nos pacientes com doença arterial obstrutiva periférica (DAOP) contribui para a redução da capacidade deambulatórida. Entretanto, ainda existe uma grande variabilidade nas correlações entre medidas inferenciais de comprometimento de fluxo e testes de deslocamento. OBJETIVO: Estabelecer o nível de correlação entre as medidas do índice tornozelo-braço (ITB), pré e pós-esforço, com um novo teste de deambulação chamado teste de deslocamento bidirecional progressivo (TDBP). MÉTODOS: Vinte e um pacientes claudicantes, com diagnóstico de DAOP, tiveram registrados o ITB antes e após a realização de um teste de caminhada no solo, com controle externo e progressivo de velocidade (TDBP). RESULTADOS: Foram registrados a distância (261,07±160,63 metros), o tempo (292,30±122,61 segundos) e a velocidade (1,23±0,34 m/s) obtidos no início do surgimento de sintoma claudicante, bem como durante o surgimento de sintoma limitante (369,52±157,97 metros, 377,71±104,60 segundos, 1,46±0,29 m/s, respectivamente). A média do ITB de repouso foi de 0,66±0,14, e de pós-esforço foi de 0,42±0,19. Não se observou nenhuma correlação importante entre as variáveis do teste (distância, tempo e velocidade) com o ITB de repouso e nem após esforço. CONCLUSÃO: O tempo, velocidade e distância de surgimento de sintoma claudicante e de sintoma claudicante limitante durante o teste de caminhada progressiva são independentes da medida inferencial de fluxo sangüíneo através do ITB de repouso e pós-exercício.