The shuttle walk exercise test in idiopathic pulmonary fibrosis

Validity and reliability of the Glittre-ADL test in individuals with idiopathic pulmonary fibrosis

BACKGROUND

Patients with idiopathic pulmonary fibrosis (IPF) often present with dyspnea, fatigue, and desaturation. These symptoms can be highly limiting, as they lead to a decrease in performing activities of daily living (ADL). Therefore, it is essential to evaluate the degree of functional limitation of these individuals.

OBJECTIVE

The present study aimed to evaluate the validity and reliability of the Glittre-ADL test (TGlittre) and its association with self-reported limitation in ADL and health-related quality of life (HRQoL) in patients with IPF.

METHODS

Twenty-seven individuals with IPF (60.5 ± 10.6 years), with forced vital capacity 2.26 ± 1.03 L (51.09 ± 20.62% of predicted) were assessed for the time spent in TGlittre, 6-minute walking distance (6MWD), limitation in ADL and HRQoL.

RESULTS

TGlittre was reliable (intraclass correlation coefficient3,1 = 0.96; P < .001); however, a learning effect of 10.6% was observed between the first and second execution of TGlittre. The time spent in TGlittre correlated with 6MWD, limitation in ADL, and disease-specific HRQoL (P < .05).

CONCLUSION

TGlittre is valid and reliable for assessing functional capacity in patients with IPF. Still, it presents a learning effect and should be performed twice when assessing functional capacity in clinical practice.

Effect of home-based pulmonary rehabilitation on functional capacity in people with idiopathic pulmonary fibrosis-a systematic review protocol

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is one of the common types of interstitial lung disease having high prevalence and mortality worldwide. As a result of patient-centred hindering factors of adherence to centre-based pulmonary rehabilitation (PR), home-based PR is an alternate mode of rehabilitating individuals with IPF. This systematic review will evaluate the effectiveness of unsupervised home-based PR on functional capacity and health-related quality of life (HRQoL) in individuals with IPF.

METHODS

Clinically stable, high resolution computed tomography and physician diagnosed IPF participants having modified Medical Research Council score below 5 will be considered for the systematic review. Studies involving home-based PR as an intervention to treat individuals with IPF will be considered. Randomised controlled trials and quasi-randomised studies (with two groups followed up) are eligible to be included. Outcomes of our interest are functional capacity (6-min walk distance, shuttle walk test and incremental shuttle walk test) and secondary outcome measure would include assessment of quality of life and adverse effects of intervention. Electronic databases such as SCOPUS, Medline (PubMed and Web of Science), PEDRo and CINAHL will be searched using database specific terms. Additionally, forward and backward citations of included studies will be searched to identify potential records. Two review authors, independently, will conduct the screening, data extraction using a customised standard tool, and critical appraisal using Cochrane Risk of Bias 2 tool of included studies. If data permits, meta-analysis will be conducted. In case of substantial heterogeneity, we will do a narrative synthesis. Subgroup analysis will be undertaken based on various contextual and interventional factors.

DISCUSSION

This review will provide comprehensive evidence on the effectiveness of unsupervised home-based PR to physiotherapists, policy makers and researchers who are interested in IPF management. Findings from this review may guide the development and evaluation of more robust evidence based home-based PR that aimed to improve functional capacity among people with IPF.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020213883.

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.

Peak aerobic capacity from incremental shuttle walk test in chronic kidney disease

BACKGROUND

Assessment of cardiorespiratory fitness is an important outcome in chronic kidney disease (CKD). We aimed to develop a predictive equation to estimate peak oxygen uptake (VO_2peak ) and power output (W_Peak ), as measured during a cardiopulmonary exercise test (CPET), from the distance walked (DW) during the incremental shuttle walk test (ISWT).

METHODS

Thirty-six non-dialysing patients with CKD [17 male, age: 61 ± 12 years, eGFR: 25±7 ml/min/1.73 m² , body mass index (BMI): 31 ± 6 kg/m² ] carried out laboratory-based CPET on a cycle ergometer and ISWT on two separate occasions.

RESULTS

Linear regression revealed that DW/BMI was a significant predictor of VO_2Peak (r = 0.78) (VO_2Peak (ml/min/kg) = [0.5688 × (DW/BMI) (m)] + 11.50). No difference (p = 0.66) between CPET VO_2Peak (19.9 ± 5.5 ml/min/kg) and predicted VO_2Peak (19.9 ± 4.3 ml/min/kg) was observed. DW multiplied by body mass (BM) was a significant predictor of W_Peak (r = 0.80) [W_Peak (W) = (0.0018 × (DW × BM)) + 50.47]. No difference (p = 0.97) between CPET W_Peak (116.2 ± 38.9 W) and estimated W_Peak (113.9 ± 30.1 W) was seen.

CONCLUSION

The present study demonstrates that VO_2Peak and W_Peak can be accurately estimated using the DW during an ISWT in CKD populations.

Incremental shuttle walk test performed in a hallway and on a treadmill: are they interchangeable?

ABSTRACT The performances of healthy individuals in an incremental shuttle walking test performed in a hallway (ISWT-H) and on a treadmill (ISWT-T) were compared to assess their physiological responses during aerobic training sessions with the speeds estimated from both tests. This was a cross-sectional study with 55 healthy subjects, who were randomized to perform the ISWT tests with 24 hours between them. Training sessions were held using a treadmill at 75% of the speeds obtained from the ISWT-H and ISWT-T. Measurements included walking distance, oxygen uptake (VO2), carbon dioxide (VCO2) production, heart rate (HR), and ventilation (VE). There was a significant difference between walking distances (ISWT-T: 823.9±165.2 m and ISWT-H:685.4±141.4 m), but similar physiological responses for VO2 (28.6±6.6 vs. 29.0±7.3 ml-1.kg-1.min-1), VCO2 (1.9±0.7 vs. 1.9±0.5 1), HR (158.3±17.8 vs. 158.6±17.7 bpm), and VE (41.5±10.4 vs. 43.7±12.9 1). The estimated speeds were different for the training sessions (5.5±0.5 km/h and 4.9±0.3 km/h), as well as the VO2, VCO2, VE, and HR. It was concluded that in healthy young adults, ISWTs carried out in a hallway and on a treadmill are not interchangeable. Since the ISWT-H was determined to have lower speed, the training intensity based on this test may underestimate a patient’s responses to aerobic training.

Validity, responsiveness and minimum clinically important difference of the incremental shuttle walk in idiopathic pulmonary fibrosis: a prospective study

The incremental shuttle walk (ISW) is well validated in COPD but limited psychometric data restrict its use in idiopathic pulmonary fibrosis (IPF). Study 1: 50 patients performed the ISW and 6 min walk test (6MWT). Study 2: 72 patients completed the ISW before and after pulmonary rehabilitation (PR). The ISW correlated strongly with 6MWT distance (r=0.81,p<0.0001). Mean (95% confidence interval) improvement in ISW with PR was 54 (38 to 70) m with an effect size of 0.29. Distribution-based and anchor-based minimum clinically important difference (MCID) estimates ranged from 31 to 46 m. The ISW is valid and responsive in IPF, with an anchor-based MCID estimate similar to that observed in chronic obstructive pulmonary disease.

TRIAL REGISTRATION NUMBER

Pre-results; NCT02530736, NCT02436278.

Cardiorespiratory responses and prediction of peak oxygen uptake during the shuttle walking test in healthy sedentary adult men

Background

The application of the Shuttle Walking Test (SWT) to assess cardiorespiratory fitness and the intensity of this test in healthy participants has rarely been studied. This study aimed to assess and correlate the cardiorespiratory responses of the SWT with the cardiopulmonary exercise testing (CEPT) and to develop a regression equation for the prediction of peak oxygen uptake (VO2 peak) in healthy sedentary adult men.

Methods

In the first stage of this study, 12 participants underwent the SWT and the CEPT on a treadmill. In the second stage, 53 participants underwent the SWT twice. In both phases, the VO2 peak, respiratory exchange ratio (R), and heart rate (HR) were evaluated.

Results

Similar results in VO2 peak (P>0.05), R peak (P>0.05) and predicted maximum HR (P>0.05) were obtained between the SWT and CEPT. Both tests showed strong and significant correlations of VO2 peak (r = 0.704, P = 0.01) and R peak (r = 0.737, P<0.01), as well as the agreement of these measurements by Bland-Altman analysis. Body mass index and gait speed were the variables that explained 40.6% (R2 = 0.406, P = 0.001) of the variance in VO2 peak. The results obtained by the equation were compared with the values obtained by the gas analyzer and no significant difference between them (P>0.05) was found.

Conclusions

The SWT produced maximal cardiorespiratory responses comparable to the CEPT, and the developed equation showed viability for the prediction of VO2 peak in healthy sedentary men.

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.

Reference values for the incremental shuttle walk test in healthy subjects: from the walk distance to physiological responses

OBJECTIVE:

To determine reference values for incremental shuttle walk distance (ISWD) and peak physiological responses during the incremental shuttle walk test (ISWT), as well as to develop a series of predictive equations for those variables in healthy adults.

METHODS:

We evaluated 103 healthy participants ≥ 40 years of age (54 women and 49 men). We fitted each participant with a gas analysis system for use during the ISWT. Oxygen consumption (VO₂), carbon dioxide production, minute ventilation, heart rate (HR), ISWD, and maximal walking velocity (MWV) were obtained as primary outcomes. We also assessed hand grip strength (HGS) and lean body mass (LBM).

RESULTS:

The regression analysis models, including physiological variables, ISWD, and MWV (adjusted for age, body mass, height, and sex), produced R² values ranging from 0.40 to 0.65 (for HR and peak VO₂, respectively). Using the models including LBM or HGS, we obtained no significant increase in the R² values for predicting peak VO₂, although the use of those models did result in slight increases in the R² values for ISWD and MWV (of 8% and 12%, respectively). The variables ISWD, MWV, and ISWD × body mass, respectively, explained 76.7%, 73.3%, and 81.2% of peak VO₂ variability.

CONCLUSIONS:

Our results provide reference values for ISWD and physiological responses to the ISWT, which can be properly estimated by determining simple demographic and anthropometric characteristics in healthy adults ≥ 40 years of age. The ISWT could be used in assessing physical fitness in the general adult population and in designing individualized walking programs.

Physiological responses to maximal exercise testing and the modified incremental shuttle walk test in adults after thermal injury: a pilot study

The ongoing hypermetabolic response associated with burn injury contributes significantly to loss of function, morbidity, and mortality. Exercise is strongly recommended to assist recovery and overall functional outcome. To date, there have been limited studies investigating the validity and practicality of both maximal laboratory and field tests in adult burns survivors. The objective of this study was to determine the metabolic and ventilatory response to cardiopulmonary maximal exercise testing (CPET) and the modified shuttle walk test (MSWT) in adult burns patients. Fifteen people (13 male) with a mean TBSA of 38.5% (16.0%) underwent both MSWT and CPET within a 5-day period in random order. The majority of participants demonstrated a normal response to CPET. Two participants with a history of inhalation burns demonstrated a respiratory limitation to exercise with desaturation (91 and 89%) at the end of the CPET, which returned to normal within 2 minutes after exercise. The correlation between VO(2peak) as measured via CPET and distance as measured in MSWT was 0.7. Mean results measured in MSWT for maximal heart rate and perceived exertion scores were lower than those achieved with CPET results: 91 and 88%, respectively. There were no adverse events during both the MSWT and CPET. This study demonstrates that after burn injury, CPET and MSWT can be performed safely in the majority of patients early in the postdischarge rehabilitation period. MSWT is likely to be submaximal at 80 to 90% of CPET results but is easy to replicate and cost-effective, thus a viable mechanism for monitoring aerobic capacity.

Ganciclovir antiviral therapy in advanced idiopathic pulmonary fibrosis: an open pilot study

Hypothesis. Repeated epithelial cell injury secondary to viruses such as Epstein Barr and subsequent dysfunctional repair may be central to the pathogenesis of IPF. In this observational study, we evaluated whether a combination of standard and anti-viral therapy might have an impact on disease progression. Methods. Advanced IPF patients who failed standard therapy and had serological evidence of previous EBV, received ganciclovir (iv) at 5 mg/kg twice daily. Forced vital capacity (FVC), shuttle walk test, DTPA scan and prednisolone dose were measured before and 8 weeks post-treatment. Results. Fourteen patients were included. After ganciclovir, eight patients showed improvement in FVC and six deteriorated. The median reduction of prednisolone dose was 7.5 mg (44%). Nine patients were classified “responders” of whom four showed an improvement in all four criteria, while three of the five “non-responders” showed no response in any of the criteria. Responders showed reduction in prednisolone dosage (P = .02) and improved DTPA clearance (P = .001). Conclusion. This audit outcome suggests that 2-week course of ganciclovir (iv) may attenuate disease progression in a subgroup of advanced IPF patients. These observations do not suggest that anti-viral treatment is a substitute for the standard care, however, suggests the need to explore the efficacy of ganciclovir as adjunctive therapy in IPF.

Exercise limitation in interstitial lung disease - mechanisms, significance and therapeutic options

Exercise limitation is a cardinal feature of the interstitial lung diseases and is frequently associated with marked dyspnoea on exertion. People with interstitial lung disease exhibit a rapid, shallow breathing pattern during exercise that worsens as disease progresses. Despite this, ventilatory mechanics are not the major limitation to exercise in most patients, with impaired gas exchange and circulatory limitation playing a more important role. Peripheral and respiratory muscle dysfunction may also contribute to impaired exercise tolerance, either due to systemic manifestations of the underlying disease, treatment side-effects or deconditioning. Measures of exercise capacity or desaturation obtained from maximal and submaximal exercise tests are good predictors of survival in patients with idiopathic pulmonary fibrosis. However, to date few pharmaceutical treatments have affected exercise outcomes despite improvements in other important clinical markers. Supplemental oxygen acutely improves exercise capacity in interstitial lung disease and is recommended for hypoxic patients, although quality of life or survival benefits have not yet been demonstrated. Exercise training improves walking capacity and dyspnoea in short-term trials and is useful to maximize functional capacity. The role of exercise testing in the routine management of patients with interstitial lung disease is not clearly defined. However, given the poor prognosis in patients with idiopathic pulmonary fibrosis and the marked variation in clinical course, assessment of exercise capacity may provide useful information for both clinicians and patients when evaluating the risks and benefits of new treatments. The extent of resting or exercise-induced hypoxia in patients with interstitial lung disease may influence the selection of an appropriate exercise test, and oxygen administration should be standardized on repeat testing.

Use of the 15-steps climbing exercise oximetry test in patients with idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is often associated with exercise-induced hypoxemia. Although maximal oxygen consumption (VO2(max)) is considered the gold-standard index of functional capacity in IPF, its measurement requires sophisticated equipment and trained personnel. The aim of the present study was to investigate the value of the simple 15-steps climbing exercise oximetry test in patients with IPF. The 15-steps climbing test was administered to 51 patients with IPF. Pulmonary function tests (PFTs), cardiopulmonary exercise test (CPET), and the 6-min walk distance (6MWD) test were performed in the same session. Oxygen saturation in the 15-steps climbing test was measured by continuous oximetry, and quantified oxygen desaturation was determined by calculating the area under the curve of oxygen saturation from the beginning of exercise through the lowest desaturation point until recovery to baseline ("desaturation area"). There was a statistically significant correlation between all parameters of the 15-steps climbing test and both VO2(max)) on the CPET (lowest saturation, p=0.002, r=0.43; saturation difference, p=0.02, r=-0.33; recovery time, p=0.02, r=-0.32; and desaturation area, p=0.005, r=-0.39), and carbon dioxide diffusion in the lungs (DLCO) on the PFTs (lowest saturation, p=0.0001, r=0.52; saturation difference, p=0.0002, r=-0.50; recovery time, p=0.0001, r=-0.53; and desaturation area, p=0.0001, r=-0.53). On stepwise linear regression analysis, independent significant predictors of VO2(max) were lowest saturation on the 15-steps test and the 6MWD. We concluded that the 15-steps oximetry test is a simple and accurate bedside tool for the evaluation of functional capacity in patients with IPF.

A double blind randomised placebo controlled pilot study of oral co-trimoxazole in advanced fibrotic lung disease

BACKGROUND

In 1996, clinical improvement with oral co-trimoxazole was noted in a patient with biopsy proven advanced fibrotic lung disease who was awaiting a lung transplant. Subsequently, 14 patients with end stage fibrotic lung disease also responded to oral co-trimoxazole. This prompted a double blind randomised placebo controlled pilot study in patients with advanced stages of idiopathic interstitial pneumonias (IIP) to objectively measure benefit.

PATIENTS

Twenty patients (aged 49-84 years; 11 males) with progressive fibrotic lung disease who had differing subtype diagnosis from CT scans of progressive fibrotic IIP, and showed oxygen desaturation on exertion were selected.

METHOD

A detailed assessment of arterial gases, lung function, and progressive shuttle-walking tests combined with oxygen saturation monitoring. Quality of life data was recorded. Randomisation was to co-trimoxazole or identical placebo for 3 months followed by 6 weeks of pulmonary rehabilitation before decoding. Placebo patients received active treatment upon decoding with continued follow up of all patients.

MAIN OUTCOME MEASURES

Primary 1. Shuttle walking test. Secondary 2. FVC and quality of life.

RESULTS

Active treatment showed a significant improvement in shuttle walking test from 255 to 355 m (p=0.002) (95% CI 200-450) with reduced oxygen desaturations during exercise (p=0.003). FVC improved on treatment (+21%) from median 1.9 to 2.3 L (p=0.05) (95% CI 1.3-3.0) but TLC and DLCO were not significantly changed although stable at 12 months. The MRC 5 Point Dyspnoea Score showed improvement (p=0.05) at 3 months for the active group which was maintained at 12 months. The SGHRQ showed a significant reduction in symptom scores at 12 months (p=0.05). The placebo group showed no significant change in any parameters, but demonstrated identical improvement following oral co-trimoxazole. Serum vascular endothelial growth factor (VEGF) was reduced 50% in the active group at 3 months, but just failed to reach statistical significance. 'Out of study' HRCT scans in 12 patients showed significant reduction in ground glass changes (p=0.05) after 12 months of continuous co-trimoxazole treatment.

CONCLUSION

The findings of the pilot study show significant improvements in objective and subjective parameters which fulfil the ATS/ERS (2000) criteria of 'a favourable response to treatment'.

Tests de marche : une avancée dans l'évaluation fonctionnelle cardiorespiratoire

Exercise testing provides information on physical capacity during exercise in addition to spirometric measures of lung function or assessment on treadmills or ergonomic cycle. The "gold standard" assessment of exercise tolerance is measured in the laboratory using treadmills or ergonomic cycle but the necessary equipment is expensive and may not be readily accessible; such tests require people used to work with children. Walking tests are field tests providing a valid and easily accessible method of measuring function-limited exercise tolerance in patients with respiratory or cardiac chronic diseases. These walking tests are non-threatening, inexpensive, easy to perform and to understand for children. Walking tests performed in daily practice are the following: "time-based" tests (2-, 6- or 12-min walking test), 3-min step test (on a step) and the shuttle walking test. It may be a useful measure to assess therapeutic intervention and provide information on the prognosis. They are simple and safe methods to evaluate quality of life in these patients.

Exercise testing determines survival in patients with diffuse parenchymal lung disease evaluated for lung transplantation

STUDY OBJECTIVES

Diffuse parenchymal lung disease is associated with a high risk of mortality despite early referral and listing for lung transplantation. We hypothesized that cardiopulmonary exercise test results and the distance walked in 6min (6MWTD) would be associated with survival in patients with diffuse parenchymal lung disease referred for lung transplantation.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care center.

PATIENTS

We included 51 consecutive patients with diffuse parenchymal lung disease who underwent exercise testing after referral to the Lung Transplant Program at the New York Presbyterian Hospital between January 2000 and December 2002. Thirty-three patients were listed, and 7 underwent transplantation during the study period. There were 17 deaths with 1 death post-transplantation.

RESULTS

A 6MWTD < 350 m was associated with an increased risk of death (HR = 4.6, 95% CI 1.5-14.2, P = 0.009). Oxygen saturation with unloaded exercise (HR = 0.91, 95% CI 0.84-0.98, P = 0.015) and oxygen consumption at peak exercise adjusted for weight (HR = 0.88, 95% CI 0.79-0.99, P = 0.039) were also associated with the risk of death. A patient with oxygen saturation <95% during unloaded exercise had a 75% chance of dying on the list for transplantation. A patient with 6MWTD < 350 m had a 67% chance of dying on the list.

CONCLUSIONS

Cardiopulmonary exercise test parameters and the 6MWTD were associated with the risk of death. Measures during exercise may be useful for determination of prognosis and for prioritizing patients with diffuse parenchymal lung disease for lung transplantation.