Resting and exercise physiology in interstitial lung diseases

Effect of breathing exercises on patients with interstitial lung disease: A systematic review and meta-analysis

PURPOSE

This study was designed to synthesize the efficacy and safety of breathing exercises in interstitial lung disease (ILD) patients by reviewing the literature and comparing the impact of different control group types, ILD subtypes, breathing exercise action modes or methods, and intervention durations on clinical efficacy.

METHODS

Systematic searches were conducted across 9 electronic databases, including PubMed, to retrieve English and Chinese studies reporting on ILD patients from inception to February 12, 2024. Study selection and data extraction were independently conducted by two researchers. The quality of the included studies was assessed using the Cochrane risk of bias tool. The data were analysed using RevMan 5.4 and STATA 17.0 software.

RESULTS

The search identified 25 studies. Compared to the control group, the breathing exercise group exhibited significantly improved lung function (FVC%pred: MD  =  3.46, 95%CI = 1.04 to 5.88; DLCO%pred: MD = 3.20, 95% CI = 2.91 to 3.48), dyspnoea (MRC or mMRC scale: MD = - 0.50, 95%CI = - 0.77 to - 0.22), exercise capacity (6MWD: MD = 32.65, 95% CI = 14.77 to 50.53), and HRQoL (SGRQ: MD = - 6.53, 95% CI = - 8.72 to - 4.34) in ILD patients. According to the subgroup analysis, significant improvements consistent with the overall results were observed in the control group with usual treatment. Compared with the control group, breathing exercises had varying degrees of improvement in the mixed diagnostic group, known-cause group, and fibrotic group of ILD patients; breathing exercises alone significantly improved DLCO%pred, MRC (or mMRC), and SGRQ; and the improvement in breathing exercises as part of pulmonary rehabilitation (PR) was more notable. Different durations of breathing exercise could promote the efficacy of different aspects of treatment for ILD patients.

CONCLUSIONS

Compared with usual treatment, breathing exercises can improve lung function, exercise capacity, and HRQoL in ILD patients, particularly without high requirements for intervention duration. The efficacy of breathing exercises varies for different ILD subtypes, and incorporating breathing exercises as part of PR can be more beneficial for ILD patients. No studies have shown significant risks for ILD patients engaging in breathing exercises.

Effects of different exercise training programs on the functional performance in fibrosing interstitial lung diseases: A randomized trial

Objectives

We aimed to compare the effects of different aerobic exercise training (ET) programs on respiratory performance, exercise capacity, and quality of life in fibrosing interstitial lung diseases (f-ILD).

Methods

A case-control study where 31 patients with f-ILD diagnosis based on chest high-resolution computed tomography were recruited from Main Alexandria University hospital-Egypt. Ten patients were randomly assigned for only lower limbs (LL) endurance training program, and 10 patients for upper limbs, lower limbs, and breathing exercises (ULB) program for consecutive 18 sessions (3 sessions/week for 6 consecutive weeks). Eleven patients who refused to participate in the ET program were considered as control. All patients were subjected for St George’s respiratory questionnaire (SGRQ), 6-minute walk test (6-MWT), forced spirometry and cardiopulmonary exercise testing (CPET) before and after ET programs.

Results

Fibrosing non-specific interstitial pneumonia (NSIP) and collagenic associated-ILD were the commonest pathologies among the ET groups (30% each) with mean age of 44.4±12.25 and 41.90±7.58 years for LL and ULB groups respectively and moderate-to-severe lung restriction. 6-MWT and SGRQ significantly improved after both ET programs (p<0.001). Peak oxygen consumption (VO2) improved significantly after both LL training (median of 22 (interquartile range (IQR) = 17.0–24.0) vs. 17.5 (IQR = 13.0–23.0) ml/kg/min, p = 0.032) and ULB training (median of 13.5 (IQR = 11.0–21.0) vs. 10.5 (IQR = 5.0–16.0) ml/kg/min, p = 0.018). Further, maximal work load and minute ventilation (VE) significantly improved after both types of ET training (p<0.05); however, neither ventilation equivalent (VE/VCO2) nor FVC% improved after ET (p = 0.052 and 0.259 respectively). There were no statistically significant important differences between LL and ULB training programs regarding 6-MWT, SGRQ or CPET parameters (p>0.05).

Conclusions

ET was associated with improvements in exercise capacity and quality of life in f-ILD patients irrespective of the type of ET program provided.

Effects of High and Moderate-Intensity Interval Training on Pulmonary and Performance Parameters in Miners Suffering From Chronic Obstructive Pulmonary Diseases

OBJECTIVE

To characterize the effect of 12 weeks of high and moderate-intensity interval training on pulmonary and functional parameters in miners with chronic obstructive pulmonary disease working in the polluted environment.

METHODS

Forty-five miners with COPD (average degree: 60 > FEV1 < 70), were randomly divided into HIIT (with 100%-125% ISWT); MIIT (with 60%-85% ISWT), and control. The study period was 12 weeks (3 sessions per week). At the beginning and end of the study, pulmonary and functional indices was evaluated.

RESULTS

Based on results, HIIT and MIIT significantly increased FVC, FEV1, and mean traveled distance in ISWT compared with control. Comparison of training intensities showed that HIIT led to a significant change in FVC, FEV1, and ISWT record compared to MIIT.

CONCLUSION

It is suggested that miners suffering from COPD, consider HIIT as part of their treatment plan.

Pulmonary rehabilitation for interstitial lung disease

BACKGROUND

Interstitial lung disease (ILD) is characterised by reduced functional capacity, dyspnoea and exercise-induced hypoxia. Pulmonary rehabilitation is often used to improve symptoms, health-related quality of life and functional status in other chronic lung conditions. There is accumulating evidence for comparable effects of pulmonary rehabilitation in people with ILD. However, further information is needed to clarify the long-term benefit and to strengthen the rationale for pulmonary rehabilitation to be incorporated into standard clinical management of people with ILD. This review updates the results reported in 2014.

OBJECTIVES

To determine whether pulmonary rehabilitation in people with ILD has beneficial effects on exercise capacity, symptoms, quality of life and survival compared with no pulmonary rehabilitation in people with ILD. To assess the safety of pulmonary rehabilitation in people with ILD.

SEARCH METHODS

We searched CENTRAL, MEDLINE (Ovid), Embase (Ovid), CINAHL (EBSCO) and PEDro from inception to April 2020. We searched the reference lists of relevant studies, international clinical trial registries and respiratory conference abstracts to look for qualifying studies.

SELECTION CRITERIA

We included randomised controlled trials and quasi-randomised controlled trials in which pulmonary rehabilitation was compared with no pulmonary rehabilitation or with other therapy in people with ILD of any origin.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted data and assessed risk of bias. We contacted study authors to request missing data and information regarding adverse effects. We specified a priori subgroup analyses for participants with idiopathic pulmonary fibrosis (IPF) and participants with severe lung disease (low diffusing capacity or desaturation during exercise). There were insufficient data to perform the prespecified subgroup analysis for type of exercise training modality.

MAIN RESULTS

For this update, we included an additional 12 studies resulting in a total of 21 studies. We included 16 studies in the meta-analysis (356 participants undertook pulmonary rehabilitation and 319 were control participants). The mean age of participants ranged from 36 to 72 years and included people with ILD of varying aetiology, sarcoidosis or IPF (with mean transfer factor of carbon dioxide (TLCO) % predicted ranging from 37% to 63%). Most pulmonary rehabilitation programmes were conducted in an outpatient setting, with a small number conducted in home-based, inpatient or tele-rehabilitation settings. The duration of pulmonary rehabilitation ranged from three to 48 weeks. There was a moderate risk of bias due to the absence of outcome assessor blinding and intention-to-treat analyses and the inadequate reporting of randomisation and allocation procedures in 60% of the studies. Pulmonary rehabilitation probably improves the six-minute walk distance (6MWD) with mean difference (MD) of 40.07 metres, 95% confidence interval (CI) 32.70 to 47.44; 585 participants; moderate-certainty evidence). There may be improvements in peak workload (MD 9.04 watts, 95% CI 6.07 to 12.0; 159 participants; low-certainty evidence), peak oxygen consumption (MD 1.28 mL/kg/minute, 95% CI 0.51 to 2.05; 94 participants; low-certainty evidence) and maximum ventilation (MD 7.21 L/minute, 95% CI 4.10 to 10.32; 94 participants; low-certainty evidence). In the subgroup of participants with IPF, there were comparable improvements in 6MWD (MD 37.25 metres, 95% CI 26.16 to 48.33; 278 participants; moderate-certainty evidence), peak workload (MD 9.94 watts, 95% CI 6.39 to 13.49; low-certainty evidence), VO₂ (oxygen uptake) peak (MD 1.45 mL/kg/minute, 95% CI 0.51 to 2.40; low-certainty evidence) and maximum ventilation (MD 9.80 L/minute, 95% CI 6.06 to 13.53; 62 participants; low-certainty evidence). The effect of pulmonary rehabilitation on maximum heart rate was uncertain. Pulmonary rehabilitation may reduce dyspnoea in participants with ILD (standardised mean difference (SMD) -0.36, 95% CI -0.58 to -0.14; 348 participants; low-certainty evidence) and in the IPF subgroup (SMD -0.41, 95% CI -0.74 to -0.09; 155 participants; low-certainty evidence). Pulmonary rehabilitation probably improves health-related quality of life: there were improvements in all four domains of the Chronic Respiratory Disease Questionnaire (CRQ) and the St George's Respiratory Questionnaire (SGRQ) for participants with ILD and for the subgroup of people with IPF. The improvement in SGRQ Total score was -9.29 for participants with ILD (95% CI -11.06 to -7.52; 478 participants; moderate-certainty evidence) and -7.91 for participants with IPF (95% CI -10.55 to -5.26; 194 participants; moderate-certainty evidence). Five studies reported longer-term outcomes, with improvements in exercise capacity, dyspnoea and health-related quality of life still evident six to 12 months following the intervention period (6MWD: MD 32.43, 95% CI 15.58 to 49.28; 297 participants; moderate-certainty evidence; dyspnoea: MD -0.29, 95% CI -0.49 to -0.10; 335 participants; SGRQ Total score: MD -4.93, 95% CI -7.81 to -2.06; 240 participants; low-certainty evidence). In the subgroup of participants with IPF, there were improvements at six to 12 months following the intervention for dyspnoea and SGRQ Impact score. The effect of pulmonary rehabilitation on survival at long-term follow-up is uncertain. There were insufficient data to allow examination of the impact of disease severity or exercise training modality. Ten studies provided information on adverse events; however, there were no adverse events reported during rehabilitation. Four studies reported the death of one pulmonary rehabilitation participant; however, all four studies indicated this death was unrelated to the intervention received.

AUTHORS' CONCLUSIONS

Pulmonary rehabilitation can be performed safely in people with ILD. Pulmonary rehabilitation probably improves functional exercise capacity, dyspnoea and quality of life in the short term, with benefits also probable in IPF. Improvements in functional exercise capacity, dyspnoea and quality of life were sustained longer term. Dyspnoea and quality of life may be sustained in people with IPF. The certainty of evidence was low to moderate, due to inadequate reporting of methods, the lack of outcome assessment blinding and heterogeneity in some results. Further well-designed randomised trials are needed to determine the optimal exercise prescription, and to investigate ways to promote longer-lasting improvements, particularly for people with IPF.

Clinical Improvement and Effectiveness of Exercise-Based Pulmonary Rehabilitation in Patients With Idiopathic Pulmonary Fibrosis: A BRIEF ANALYTICAL REVIEW

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease associated with high mortality rates and poor clinical condition. Exercise-based pulmonary rehabilitation (EBPR) has been demonstrated to be effective in improving 6-min walk distance (6MWD), although the clinical improvement and effectiveness are less characterized. The current review examined the existing evidence of EBPR among patients with IPF and aimed to analyze the effect of EBPR on clinical improvement and effectiveness.

METHODS

A systematic databases search (MEDLINE/PubMed, EMBASE, and the Cochrane Library) was conducted for available publications as of January 2020. Randomized controlled trials (RCTs) and meta-analyses of RCTs examining the effect of EBPR in patients with IPF were reviewed. Mean difference for RCTs and weighted mean difference for meta-analyses between the EBPR arm and the usual-care arm in 6MWD were compared with the established minimal clinically important difference (MCID) of 30 m. Clinical improvement following EBPR was determined when mean difference and weighted mean difference were equal or exceeding the MCID. Effectiveness of EBPR was assessed using the number needed to treat (NNT) analysis.

RESULTS

Five independent RCTs (including 21-61 patients/study) and five meta-analyses (including two to five studies with 62-169 patients/meta-analysis) were included. The mean difference of 6MWD ranged from 16-81 m in RCTs. Three of five RCTs demonstrated an average improvement that meets or exceeds the MCID. Two RCTs showed favorable improvement in 6MWD but did not reach the MCID. The weighted mean difference of 6MWD ranged from 27-49 m in the meta-analyses. Four of five meta-analyses showed an average improvement that meets or exceeds the MCID. One early meta-analysis of only two RCTs showed significant improvement, although did not reach the MCID. The NNT in three RCTs and four meta-analyses that met clinical improvement in 6MWD was one.

CONCLUSIONS

This review provides novel evidence with respect to clinical improvement and high effectiveness of EBPR among patients with IPF. The results suggest that, on average, the majority of patients would be expected to clinically improve by completing the EBPR program. The findings further support the prescription of EBPR as clinically effective therapy and implementation as standard of care for patients with IPF. Future studies examining clinical improvement and effectiveness utilizing additional outcomes with the MCID are warranted.

Cardiopulmonary Exercise Testing in Patients With Interstitial Lung Disease

Interstitial lung disease (ILD) is a heterogeneous group of conditions characterized by fibrosis and/or inflammation of the lung parenchyma. The pathogenesis of ILD consistently results in exertional dyspnea and exercise intolerance. Cardiopulmonary exercise testing (CPET) provides important information concerning the pathophysiology of ILD that can help inform patient management. Despite the purported benefits of CPET, its clinical utility in ILD is not well defined; however, there is a growing body of evidence that provides insight into the potential value of CPET in ILD. Characteristic responses to CPET in patients with ILD include exercise-induced arterial hypoxemia, an exaggerated ventilatory response, a rapid and shallow breathing pattern, critically low inspiratory reserve volume, and elevated sensations of dyspnea and leg discomfort. CPET is used in ILD to determine cause(s) of symptoms such as exertional dyspnea, evaluate functional capacity, inform exercise prescription, and determine the effects of pharmacological and non-pharmacological interventions on exercise capacity and exertional symptoms. However, preliminary evidence suggests that CPET in ILD may also provide valuable prognostic information and can be used to ascertain the degree of exercise-induced pulmonary hypertension. Despite these recent advances, additional research is required to confirm the utility of CPET in patients with ILD. This brief review outlines the clinical utility of CPET in patients with ILD. Typical patterns of response are described and practical issues concerning CPET interpretation in ILD are addressed. Additionally, important unanswered questions relating to the clinical utility of CPET in the assessment, prognostication, and management of patients with ILD are identified.

Safety of exertional desaturation in idiopathic pulmonary fibrosis: An electrocardiography study

INTRODUCTION

Exertional desaturation is a cardinal manifestation of idiopathic pulmonary fibrosis (IPF) which raises concerns for serious complications.

OBJECTIVES

To evaluate the safety of clinically significant desaturation (CSD) during exercise and to assess whether abnormal electrocardiographic (ECG) changes are associated with mortality and hospitalizations in patients with IPF.

METHODS

Thirty-four IPF patients (68 ± 8 years, 35% women) underwent maximal cycle cardiopulmonary exercise testing (CPET) using 12-lead ECG and pulse oximetry (SpO₂ ) and were followed up to 40 months. CSD was considered as SpO₂ <95% or decline from baseline ≥5%. The level of agreement between abnormal ECG changes and CSD was evaluated. Risks for mortality and hospitalizations were assessed in relation to abnormal ECG changes.

RESULTS

All patients completed CPET without adverse events or life-threating ECG changes. Comparing rest to exercise conditions, the prevalence of mild ventricular arrhythmia rose from 3% to 18% (P = .025) and CSD rose from 21% to 79% (P < .001). There was no agreement between the prevalence of arrhythmia and CSD during exercise (kappa = -.065, χ²  = .72, P = .40). A trend for lower prevalence was observed in ST-T segment deviation during exercise. Resting and exercise ECG abnormalities were not associated with mortality or hospitalizations during the follow-up.

CONCLUSIONS

CSD during CPET was not associated with ventricular arrhythmias, ischemia, or complications in patients with IPF. These findings suggest that CPET is generally a safe procedure for IPF, although carefully monitoring for signs and symptoms including ECG is strongly recommended. Additional research is warranted to confirm these results.

Differential Pulmonary Rehabilitation Outcomes in Patients With and Without COPD: ROLE OF GENDER

PURPOSE

Individuals with all forms of pulmonary disease are referred for pulmonary rehabilitation. This study examines pulmonary rehabilitation outcomes between individuals with chronic obstructive lung disease (COPD) and non-COPD disease and the impact of gender.

METHODS

This is a retrospective study at a tertiary center. The primary endpoint was the difference in 6-min walk test distance. Secondary measurements included treadmill and NuStep minutes; biceps curls and front arm raises load; quality of life measured by the St George's Respiratory Questionnaire; and University of California San Diego-Shortness of Breath Questionnaire (UCSD-SOBQ) scores.

RESULTS

Eighty patients were included: 38 men (23 COPD, 15 non-COPD) and 42 women (31 COPD, 11 non-COPD). There was a statistically significant improvement in 6-min walk test distances pre- to post-pulmonary rehabilitation for all participants, P = .0003. Although both the COPD and non-COPD groups demonstrated overall improvement (P < .0004 and P = .02, respectively), subgroup analysis showed no statistically significant change in the non-COPD group when divided by gender. There was a significant statistical improvement in lower and upper extremity strength in all participants. Only women with COPD showed a statistically significant improvement with respect to overall quality of life as measured by St. George's Respiratory Questionnaire (P = .01). Women showed significant improvement in their depression score, as well as a trend toward improvement in the University of California San Diego-Shortness of Breath Questionnaire, while only men with COPD showed any improvement in their sleep quality measured by the Pittsburgh Sleep Quality Index.

CONCLUSIONS

Pulmonary rehabilitation results in different but improved outcomes regardless of gender or disease state.

Idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease characterized by progressive lung scarring and the histological picture of usual interstitial pneumonia (UIP). It is associated with increasing cough and dyspnoea and impaired quality of life. IPF affects ∼3 million people worldwide, with incidence increasing dramatically with age. The diagnostic approach includes the exclusion of other interstitial lung diseases or overlapping conditions and depends on the identification of the UIP pattern, usually with high-resolution CT; lung biopsy might be required in some patients. The UIP pattern is predominantly bilateral, peripheral and with a basal distribution of reticular changes associated with traction bronchiectasis and clusters of subpleural cystic airspaces. The biological processes underlying IPF are thought to reflect an aberrant reparative response to repetitive alveolar epithelial injury in a genetically susceptible ageing individual, although many questions remain on how to define susceptibility. Substantial progress has been made in the understanding of the clinical management of IPF, with the availability of two pharmacotherapeutic agents, pirfenidone and nintedanib, that decrease physiological progression and likely improve progression-free survival. Current efforts are directed at identifying IPF early, potentially relying on combinations of biomarkers that include circulating factors, demographics and imaging data.

Cardiorespiratory Response to Different Exercise Tests in Interstitial Lung Disease

INTRODUCTION

The 6-min stepper test (6MST) has been used as an alternative to the 6-min walk test (6MWT) to assess exercise tolerance in patients with interstitial lung disease (ILD). Recent data suggest that the tests may involve different energy pathways and cardiorespiratory responses. We thus aimed to compare the cardiorespiratory responses of ILD patients during the 6MWT and the 6MST.

METHODS

Thirty-one patients with ILD were randomized to perform both tests in the order 6MST → 6MWT (n = 16) or 6MWT → 6MST (n = 15). Gas exchange, HR, and pulse O2 saturation (SpO2) were measured continuously, and dyspnoea, leg discomfort, and blood lactate concentration were assessed before and immediately after each test.

RESULTS

Oxygen uptake (V˙O2) was lower (P = 0.002) and respiratory equivalent ratio for O2 (V˙E/V˙O2) and RER were higher (both P < 0.001) during the 6MST compared with the 6MWT. The 6MST was also associated with higher blood lactate concentrations (6MST, 4.16 ± 1.95 mmol·L; 6MWT, 2.84 ± 1.17 mmol·L; P = 0.01), higher leg discomfort scores (6MST 5 ± 3 points, 6MWT 3 ± 2 points; P < 0.001), and smaller decreases in SpO2 (6MST -5% ± 5%, 6MWT -9% ± 6%; P < 0.001).

CONCLUSIONS

ILD patients exhibited greater ventilatory responses and lower arterial O2 desaturation during the 6MST compared with the 6MWT. The higher lactate concentrations and perceived muscle fatigue observed during the 6MST may indicate the presence of intertest differences in active muscle metabolism that could contribute to the distinct cardiorespiratory responses.

Exertional dyspnoea in interstitial lung diseases: the clinical utility of cardiopulmonary exercise testing

Interstitial lung diseases (ILDs) represent a heterogeneous group of pathologies characterised by alveolar and interstitial damage, pulmonary inflammation (usually associated with fibrosis), decreased lung function and impaired gas exchange, which can be attributed to either a known or an unknown aetiology. Dyspnoea is one of the most common and disabling symptoms in patients with ILD, significantly impacting quality of life. The mechanisms causing dyspnoea are complex and not yet fully understood. However, it is recognised that dyspnoea occurs when there is an imbalance between the central respiratory efferent drive and the response of the respiratory musculature. The respiratory derangement observed in ILD patients at rest is even more evident during exercise. Pathophysiological mechanisms responsible for exertional dyspnoea and reduced exercise tolerance include altered respiratory mechanics, impaired gas exchange, cardiovascular abnormalities and peripheral muscle dysfunction.

This review describes the respiratory physiology of ILD, both at rest and during exercise, and aims to provide comprehensive and updated evidence on the clinical utility of the cardiopulmonary exercise test in the assessment and management of these pathological entities. In addition, the role of exercise training and pulmonary rehabilitation programmes in the ILD population is addressed.

Exercise training in idiopathic pulmonary fibrosis: is it of benefit?

Key points

Educational aims

Exercise is a well-documented safe and effective intervention for prevention and rehabilitation of chronic diseases. Idiopathic pulmonary fibrosis (IPF) is a chronic deadly lung disease associated with severe signs and symptoms, exercise intolerance, diminished quality of life and poor prognosis. In the short term, supervised exercise training programmes have demonstrated clinical benefits in improving exercise capacity, dyspnoea and quality of life in patients with IPF. The underlying mechanisms of chronic adaption to a regular exercise regimen in IPF have yet to be well described and require further investigation. The available data underscore the importance of implementing training principles to target the pathophysiological impairments of IPF in order to optimise training adaption and enhance the outcomes. The current exercise training data in IPF provide sufficient evidence of clinical benefit for consideration to be given to recommending exercise-based pulmonary rehabilitation as standard of care for IPF.

An overview of data on exercise for IPF patients, highlighting the importance of exercise training in IPF managementhttp://ow.ly/4mWCCd

Exercise training in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic devastating interstitial lung disease associated with exercise intolerance, dyspnea, hypoxemia, diminished quality of life and poor prognosis. A growing body of evidence with respect to short-term effects of exercise training has demonstrated clinical benefits in IPF patients. A recent systematic review showed significant improvements in 6-min walking distance, peak aerobic capacity, reduced dyspnea and improved quality of life. However, aspects of training programs, maintenance and predictors of improvement and the impact on prognosis need to be further explored. The aim of this paper was to comprehensively review the existing scientific literature regarding exercise training in patients with IPF and identify important gaps that should be studied in the future.

Are 30 minutes of rest between two incremental shuttle walking tests enough for cardiovascular variables and perceived exertion to return to baseline values?

Objective:

To verify whether 30 minutes of rest between two incremental shuttle walking tests (ISWT) are enough for cardiovascular variables and perceived exertion to return to baseline values in healthy subjects in a broad age range.

Method:

The maximal exercise capacity of 334 apparently healthy subjects (age ≥18) was evaluated using the ISWT. The test was performed twice with 30 minutes of rest in between. Heart rate (HR), arterial blood pressure (ABP), dyspnea, and leg fatigue were evaluated before and after each test. Subjects were allocated to 6 groups according to their age: G1: 18-29 years; G2: 30-39 years; G3: 40-49 years; G4: 50-59 years; G5: 60-69 years and G6: ≥70 years.

Results:

All groups had a good performance in the ISWT (median >90% of the predicted distance). The initial HR (HRi) of the second ISWT was higher than the first ISWT in the total sample (p<0.0001), as well as in all groups (p<0.0001). No difference was observed in the behavior of ABP (systolic and diastolic) and dyspnea between the two tests, but this difference occurred for leg fatigue (greater before the second ISWT) in G1 (p<0.05). Most subjects (58%) performed better in the second test.

Conclusion:

30 minutes of rest between two ISWTs are not enough for all cardiovascular variables and perceived exertion to return to baseline values. However, this period appears to be sufficient for blood pressure and performance to recover in most subjects.

Pulmonary rehabilitation for interstitial lung disease

BACKGROUND

Interstitial lung disease (ILD) is characterised by reduced functional capacity, dyspnoea and exercise-induced hypoxia. Pulmonary rehabilitation, an intervention that includes exercise training, is beneficial for people with other chronic lung conditions; however its effects in ILD have not been well characterised.

OBJECTIVES

• To determine whether pulmonary rehabilitation in patients with ILD has beneficial effects on exercise capacity, symptoms, quality of life and survival compared with no pulmonary rehabilitation in patients with ILD.• To assess the safety of pulmonary rehabilitation in patients with ILD.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2014, Issue 6), MEDLINE (Ovid), EMBASE (Ovid), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (EBSCO) and the Physiotherapy Evidence Database (PEDro) (all searched from inception to June 2014). We also searched the reference lists of relevant studies, international clinical trial registries and respiratory conference abstracts to look for qualifying studies.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials in which pulmonary rehabilitation was compared with no pulmonary rehabilitation or with other therapy in people with ILD of any origin were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted data and assessed risk of bias. Study authors were contacted to provide missing data and information regarding adverse effects. A priori subgroup analyses were specified for participants with idiopathic pulmonary fibrosis (IPF) and participants with severe lung disease (low diffusing capacity or desaturation during exercise). We planned to subgroup according to training modality applied, but there were insufficient data.

MAIN RESULTS

Nine studies were included, six of which were published as abstracts. Five studies were included in the meta-analysis (86 participants who undertook pulmonary rehabilitation and 82 control participants). One study used a blinded assessor and intention-to-treat analysis. No adverse effects of pulmonary rehabilitation were reported. Pulmonary rehabilitation improved the six-minute walk distance with weighted mean difference (WMD) of 44.34 metres (95% confidence interval (CI) 26.04 to 62.64 metres) and improved oxygen consumption (VO2) peak with WMD of 1.24 mL/kg/min(-1) (95% CI 0.46 to 2.03 mL/kg/min(-1)). Improvements in six-minute walk distance and VO2 peak were also seen in the subgroup of participants with idiopathic pulmonary fibrosis (IPF) (WMD 35.63 metres, 95% CI 16.02 to 55.23 metres; WMD 1.46 mL/kg/min(-1), 95% CI 0.54 to 2.39 mL/kg/min(-1), respectively). Reduced dyspnoea (standardised mean difference (SMD) -0.66, 95% CI -1.05 to -0.28) following pulmonary rehabilitation was also seen in the IPF subgroup (SMD -0.68, 95% CI -1.12 to -0.25). Quality of life improved following pulmonary rehabilitation for all participants on a variety of measures (SMD 0.59, 95% CI 0.20 to 0.98) and for the subgroup of people with IPF (SMD 0.59, 95% CI 0.14 to 1.03). Two studies reported longer-term outcomes, with no significant effects of pulmonary rehabilitation on clinical variables or survival at three or six months. Available data were insufficient to allow examination of the impact of disease severity or exercise training modality.

AUTHORS' CONCLUSIONS

Pulmonary rehabilitation seems to be safe for people with ILD. Improvements in functional exercise capacity, dyspnoea and quality of life are seen immediately following pulmonary rehabilitation, with benefits also evident in IPF. Because of inadequate reporting of methods and small numbers of included participants, the quality of evidence was low to moderate. Little evidence was available regarding longer-term effects of pulmonary rehabilitation.

Idiopathic pulmonary fibrosis and coronary artery disease

Idiopathic pulmonary fibrosis (IPF) is defined as a chronic fibrosing interstitial disease of unknown cause, limited to the lungs, and associated with the histopathologic and/or radiologic pattern of usual interstitial pneumonia (UIP); it generally progresses into respiratory failure and death. Although progression of the disease is the most common cause of death, there are increasing reports of its association with other pathologies has been reported: e.g., IPF patients seem more susceptible to cardiovascular diseases. Therefore, other pathologies might also influence the natural course. In this paper, we describe a case of IPF and coronary artery disease (CAD). We emphasize the importance of cardiopulmonary exercise test (CPET) as a useful procedure to monitor disease progression in IPF patients. We also stress the importance of a careful analysis of variables measured for an accurate interpretation of the clinical picture and an improvement of the clinical management of patients. Moreover, we suggest that a careful assessment of CPET parameters may additionally help in the early detection of high cardiovascular ischemic risk.

Sleep oxygen desaturation predicts survival in idiopathic pulmonary fibrosis

BACKGROUND

Recent studies suggest poor sleep quality in patients with idiopathic pulmonary fibrosis (IPF). However, so far, the impact of IPF-related sleep breathing disorders (SBDs) on survival has not been extensively studied.

METHODS

In a cohort of 31 (24 males) treatment-naïve, newly diagnosed consecutive IPF patients, we prospectively investigated the relationship of SBD parameters such as apnea-hypopnea index (AHI), maximal difference in oxygen saturation between wakefulness and sleep (maxdiff SpO2), and lowest sleep oxygen saturation (lowest SpO2) with clinical (survival, dyspnea, daytime sleepiness), pulmonary function, submaximal (6-min walk test [6MWT]) and maximal exercise variables (cardiopulmonary exercise test [CPET]), and right ventricular systolic pressure (RVSP).

RESULTS

Sleep oxygen desaturation exceeded significantly that of maximal exercise (p < 0.001). Maxdiff SpO2 was inversely related to survival, DLCO%, and SpO2 after 6MWT, and directly with dyspnea, AHI, and RVSP. The lowest SpO2 was directly related to survival and to functional (TLC%, DLCO%) as well as submaximal and maximal exercise variables (6MWT distance, SpO2 after 6MWT, peak oxygen consumption/kg, SpO2 at peak exercise), while an inverse association with dyspnea score, AHI, and RVSP was observed.

CONCLUSIONS

Our findings provide evidence that intermittent sleep oxygen desaturation significantly exceeds that of maximal exercise and is associated with survival in IPF patients. Furthermore, they imply the existence of a link between lung damage and apnea events resulting to the induction and severity of intermittent sleep oxygen desaturation that aggravate pulmonary arterial hypertension and influence IPF survival.

The benefits of exercise training in interstitial lung disease: protocol for a multicentre randomised controlled trial

Background

Interstitial lung disease encompasses a diverse group of chronic lung conditions characterised by distressing dyspnoea, fatigue, reduced exercise tolerance and poor health-related quality of life. Exercise training is one of the few treatments to induce positive changes in exercise tolerance and symptoms, however there is marked variability in response. The aetiology and severity of interstitial lung disease may influence the response to treatment. The aims of this project are to establish the impact of exercise training across the range of disease severity and to identify whether there is an optimal time for patients with interstitial lung disease to receive exercise training.

Methods/Design

One hundred and sixteen participants with interstitial lung disease recruited from three tertiary institutions will be randomised to either an exercise training group (supervised exercise training twice weekly for eight weeks) or a usual care group (weekly telephone support). The 6-minute walk distance, peripheral muscle strength, health-related quality of life, dyspnoea, anxiety and depression will be measured by a blinded assessor at baseline, immediately following the intervention and at six months following the intervention. The primary outcome will be change in 6-minute walk distance following the intervention, with planned subgroup analyses for participants with idiopathic pulmonary fibrosis, dust-related interstitial lung disease and connective-tissue related interstitial lung disease. The effects of disease severity on outcomes will be evaluated using important markers of disease severity and survival, such as forced vital capacity, carbon monoxide transfer factor and pulmonary hypertension.

Discussion

This trial will provide certainty regarding the role of exercise training in interstitial lung disease and will identify at what time point within the disease process this treatment is most effective. The results from this study will inform and optimise the clinical management of people with interstitial lung disease.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12611000416998

Highlights of the Brazilian Thoracic Association guidelines for interstitial lung diseases

Interstitial lung diseases (ILDs) are heterogeneous disorders, involving a large number of conditions, the approach to which continues to pose an enormous challenge for pulmonologists. The 2012 Brazilian Thoracic Association ILD Guidelines were established in order to provide Brazilian pulmonologists with an instrument that can facilitate the management of patients with ILDs, standardizing the criteria used for the diagnosis of different conditions and offering guidance on the best treatment in various situations. The objective of this article was to briefly describe the highlights of those guidelines.

Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a specific clinicopathologic ­syndrome presenting in older adults with the predominant features: dyspnea, dry cough, restrictive defect on pulmonary function tests (PFTs), hypoxemia, characteristic abnormalities on high-resolution thin section computed tomographic (HRCT) scans, usual interstitial pneumonitis (UIP) pattern on lung biopsy. Surgical lung biopsy is the gold standard of diagnosis, but the diagnosis can be established in some cases by HRCT, provided the clinical features are consistent. The cause of IPF is unknown. However, IPF is more common in adults >60 years old, smokers (current or ex), and patients with specific occupational or noxious exposures. Familial IPF, associated with several distinct genetic mutations, accounts for 1.5–3% of cases. Unfortunately, the prognosis is poor, and most patients die of respiratory failure within 3–6 years of diagnosis. However, the course is highly variable. In some patients, the disease is fulminant, progressing to lethal respiratory failure within months, whereas the course may be indolent, spanning >5 years in some patients. Therapy has not been proven to alter the course of the disease or influence mortality, but recent studies with pirfenidone and tyrosine kinase inhibitors are promising. Lung transplantation is the best therapeutic option, but is limited to selected patients with severe, life-threatening disease and no contraindications to transplant.

Diagnostic assessment of patients with interstitial lung disease

The diagnosis of interstitial lung disease (ILD) is frequently delayed because clinical clues are neglected and respiratory symptoms are ascribed to more common pulmonary diagnoses such as chronic obstructive pulmonary disease (COPD) in the primary care setting. While ILD cases ultimately require referral to a pulmonologist, general practitioners can play a crucial role in recognising the need for, and initiating, a diagnostic evaluation. An initial assessment hinges upon a structured history and physical examination with careful attention paid to occupational, environmental and drug exposures as well as a history of symptoms suggesting connective tissue disease. Ultimately a surgical lung biopsy may be indicated, but high resolution computed tomography (HRCT) chest scans are essential to the diagnostic workup since each ILD form is characterised by a specific pattern of abnormalities.

The prognostic value of cardiopulmonary exercise testing in idiopathic pulmonary fibrosis

RATIONALE

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive dyspnea, impaired gas exchange, and ultimate mortality.

OBJECTIVES

To test the hypothesis that maximal oxygen uptake during cardiopulmonary exercise testing at baseline and with short-term longitudinal measures would predict mortality in patients with idiopathic pulmonary fibrosis.

METHODS

Data from 117 patients with IPF and longitudinal cardiopulmonary exercise tests were examined retrospectively. Survival was calculated from the date of the first cardiopulmonary exercise test.

MEASUREMENTS AND MAIN RESULTS

Patients with baseline maximal oxygen uptake less than 8.3 ml/kg/min had an increased risk of death (n = 8; hazard ratio, 3.24; 95% confidence interval, 1.10-9.56; P = 0.03) after adjusting for age, gender, smoking status, baseline forced vital capacity, and baseline diffusion capacity for carbon monoxide. We were unable to define a unit change in maximal oxygen uptake that predicted survival in our cohort.

CONCLUSIONS

We conclude that a threshold maximal oxygen uptake of 8.3 ml/kg/min during cardiopulmonary exercise testing at baseline adds prognostic information for patients with IPF.

Physical training for interstitial lung disease

BACKGROUND

Interstitial lung disease (ILD) is characterised by reduced functional capacity, dyspnoea and exercise-induced hypoxia. Physical training is beneficial for people with other chronic lung conditions, however its effects in ILD have not been well characterised.

OBJECTIVES

To assess the effects of physical training on exercise capacity, symptoms, quality of life and survival compared to no physical training in people with ILD.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2007, Issue 4), MEDLINE, EMBASE, CINAHL and the Physiotherapy Evidence Database (PEDro) (all searched from inception to December 2007). The reference lists of relevant studies were hand-searched for qualifying studies.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials in which physical training was compared to no physical training or to other therapy in people with ILD of any aetiology were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted data and assessed risk of bias. Authors were contacted to obtain missing data and information regarding adverse effects. A priori subgroup analyses were specified for participants with idiopathic pulmonary fibrosis (IPF), severe lung disease and training modality.

MAIN RESULTS

Five studies were included, three of which were published as abstracts. Two studies were included in the meta-analysis (43 participants who undertook physical training and 42 control participants). One study used a blinded assessor and intention-to-treat analysis. No adverse effects of physical training were reported. Physical training improved the 6-minute walk distance with weighted mean difference (WMD) 38.61 metres (95% confidence interval 15.37 to 61.85 metres). Improvement in 6-minute walk distance was also seen in the subgroup of participants with IPF (WMD 26.55 metres, 2.81 to 50.30 metres). No effect of physical training on VO(2)peak was evident. There was a reduction in dyspnoea (standardised mean difference (SMD) -0.47, 95% CI: -0.91 to -0.04) however this did not reach significance in the IPF subgroup (SMD -0.43, 95% CI: -0.94 to 0.08). Quality of life improved following physical training in all participants (SMD 0.58, 95% CI: 0.15 to 1.02) and in IPF (SMD 0.57, 95% CI: 0.06 to 1.09). Only one study reported longer-term outcomes, with no significant effects of physical training on clinical variables or survival at six months. Insufficient data were available to examine the impact of disease severity or training modality.

AUTHORS' CONCLUSIONS

Physical training is safe for people with ILD. Improvements in functional exercise capacity, dyspnoea and quality of life are seen immediately following training, with benefits also evident in IPF. There is little evidence regarding longer-term effects of physical training.

Six-Minute Walk Test and Health Status Assessment in Sarcoidosis

BACKGROUND

The 6-min walk test has proved useful in assessing impairment and prognosis in various lung diseases.

METHODS

A prospective study of 142 sarcoidosis patients seen during a 6-week period at one tertiary sarcoidosis clinic. All patients completed spirometry, 6-min walk testing, St. George Respiratory Questionnaire (SGRQ), fatigue assessment scale, and dyspnea score. Parameters assessed included the 6-min walk distance (6MWD) and the initial and lowest oxygen saturations during the test.

RESULTS

One hundred three of 142 patients had extrapulmonary manifestations, 10 patients had left ventricular dysfunction, and 14 patients had documented pulmonary hypertension. Seventy-three patients (51%) completed a 6MWD < 400 m, and 32 patients (22%) walked < 300 m. The 14 patients with documented pulmonary hypertension had a shorter 6MWD (median, 280 m; range, 61 to 404) than those without documented pulmonary arterial hypertension (median, 411 m; range, 46 to 747; p < 0.0001). Several components of the pulmonary function and quality of life correlated with 6MWD. Using a stepwise multiple regression analysis, only SGRQ activity component (t = - 7.498, p < 0.0001), FVC (t = 4.415, p < 0.0001), and lowest oxygen saturation (t = 2.55, p < 0.02) were independent predictors of 6MWD.

CONCLUSIONS

6MWD was reduced in the majority of sarcoidosis patients. Several factors were associated with a reduced 6MWD, including FVC, oxygen saturation with exercise, and self-reported respiratory health. Both 6MWD and quality of life measures are useful in assessing the functional status of sarcoidosis patients.

Pulmonary function testing in idiopathic interstitial pneumonias

Diffuse parenchymal lung diseases are a group of disorders that involve the space between the epithelial and endothelial basement membranes and are generally segregated into four major categories. These include the idiopathic interstitial pneumonias, which are further categorized into seven clinical/radiologic/pathologic subsets. These disorders generally share a common pattern of physiologic abnormality characterized by a restrictive ventilatory defect and reduced diffusing capacity (DLCO). Pulmonary function testing is often used and recommended in their assessment and management. The potential clinical application of physiologic testing includes to aid in diagnosis, although its value in differential diagnosis is limited. Pulmonary function testing also aids in establishing disease severity and in defining prognosis. In nonspecific interstitial pneumonia and idiopathic pulmonary fibrosis, severely decreased DLCO has proven valuable in this regard. Similarly, exertional desaturation to less than 88% at baseline testing and a decrease in FVC (greater than 10%) over the course of short-term follow-up identify patients at particular risk of mortality. Finally, physiologic testing, especially spirometry and DLCO, have demonstrated value in monitoring response to therapy and identifying disease progression.