Lung clearance index (LCI2.5) changes after initiation of Elexacaftor/Tezacaftor/Ivacaftor in children with cystic fibrosis aged between 6 and 11 years: The "real-world" differs from trial data.

BACKGROUND: Elexacaftor in combination with Tezacaftor and Ivacaftor (ETI) became licensed in the United Kingdom in early 2022 for children aged 6-11 years with cystic fibrosis (CF) and an eligible mutation. Many in this age group have excellent prior lung health making quantitative measurement of benefit challenging. Clinical trials purport that lung clearance index (LCI2.5) measurement is most suitable for this purpose. OBJECTIVES: This study aimed to understand the clinical utility of LCI2.5 in detecting change after commencing ETI in the real world. PATIENT SELECTION/METHODS: Baseline anthropometric data were collected along with spirometry (forced expiratory volume in 1 s [FEV1], forced vital capacityFV and LCI2.5 measures in children aged 6-11 years with CF before starting ETI. Measures were repeated after a mean (range) of 8.2 (7-14) months of ETI treatment. The primary endpoint was a change in LCI2.5, with secondary endpoints including change in FEV1 and change in body mass index (BMI) also reported. RESULTS: Twelve children were studied (seven male, mean age 9.5 years at baseline). Our study population had a mean (SD) LCI2.5 of 7.01 (1.14) and FEV1 of 96 (13) %predicted at baseline. Mean (95% confidence interval) changes in LCI2.5 [-0.7 (-1.4, 0), p = .06] and BMI [+0.7 (+0.1, +1.3), p = .03] were observed, along with changes in FEV1 of +3.1 (-1.9, +8.1) %predicted. CONCLUSIONS: Real-world changes in LCI2.5 (-0.7) are different to those reported in clinical trials (-2.29). Lower baseline LCI2.5 as a result of prior modulator exposure, high baseline lung health, and new LCI2.5 software analyses all contribute to lower LCI2.5 values being recorded in the real world of children with CF.

Cardiopulmonary Exercise Testing Provides Prognostic Information in Advanced Cystic Fibrosis Lung Disease.

Rationale: Cardiopulmonary exercise testing (CPET) provides prognostic information in cystic fibrosis (CF); however, its prognostic value for patients with advanced CF lung disease is unknown. Objectives: To determine the prognostic value of CPET on the risk of death or lung transplant (LTX) within 2 years. Methods: We retrospectively collected data from 20 CF centers in Asia, Australia, Europe, and North America on patients with a forced expiratory volume in 1 second (FEV1) ⩽ 40% predicted who performed a cycle ergometer CPET between January 2008 and December 2017. Time to death/LTX was analyzed using mixed Cox proportional hazards regression. Conditional inference trees were modeled to identify subgroups with increased risk of death/LTX. Results: In total, 174 patients (FEV1, 30.9% ± 5.8% predicted) were included. Forty-four patients (25.5%) died or underwent LTX. Cox regression analysis adjusted for age, sex, and FEV1 revealed percentage predicted peak oxygen uptake ([Formula: see text]o2peak) and peak work rate (Wpeak) as significant predictors of death/LTX: adjusted hazard ratios per each additional 10% predicted were 0.60 (95% confidence interval, 0.43-0.90; P = 0.008) and 0.60 (0.48-0.82; P < 0.001). Tree-structured regression models, including a set of 11 prognostic factors for survival, identified Wpeak to be most strongly associated with 2-year risk of death/LTX. Probability of death/LTX was 45.2% for those with a Wpeak ⩽ 49.2% predicted versus 10.9% for those with a Wpeak > 49.2% predicted (P < 0.001). Conclusions: CPET provides prognostic information in advanced CF lung disease, and Wpeak appears to be a promising marker for LTX referral and candidate selection.

Global birth prevalence of Robin sequence in live-born infants: a systematic review and meta-analysis.

Robin sequence (RS), a congenital disorder of jaw maldevelopment and glossoptosis, poses a substantial healthcare burden and has long-term health implications if airway obstruction is suboptimally treated. This study describes the global birth prevalence of RS and investigates whether prevalence estimates differ by geographical location, ethnicity or study data source (registry versus non-registry data). The protocol was prospectively registered with PROSPERO.Databases were searched using keywords and subject terms for "Robin sequence", "epidemiology", "incidence" and "birth prevalence". Meta-analysis was performed fitting random effects models with arcsine transformation.From 34 eligible studies (n=2722 RS cases), pooled birth prevalence was 9.5 per 100 000 live births (95% CI 7.1-12.1) with statistical heterogeneity. One third of studies provided a case definition for RS and numerous definitions were used. A total of 22 countries were represented, predominantly from European populations (53% of studies). There was a trend towards higher birth prevalence in European populations and lower prevalence from registry-based studies. Only two studies reported ethnicity.This study indicates that RS occurs globally. To investigate geographical differences in prevalence, additional studies from non-European populations and reporting of ethnicity are needed. Heterogeneity of estimates may be due to variable diagnostic criteria and ascertainment methods. Recently published consensus diagnostic criteria may reduce heterogeneity among future studies.

Guidance and standard operating procedures for functional exercise testing in cystic fibrosis.

Regular exercise testing is recommended for all people with cystic fibrosis (PwCF). A range of validated tests, which integrate both strength and aerobic function, are available and increasingly being used. Together, these tests offer the ability for comprehensive exercise evaluation. Extensive research and expert consensus over recent years has enabled the adaptation and standardisation of a range of exercise tests to aid the understanding of the pathophysiology related to exercise limitation in PwCF and has led to the development of novel exercise tests which may be applied to PwCF. This article provides expert, opinion-based clinical practice guidance, along with test instructions, for a selection of commonly used valid tests which have documented clinimetric properties for PwCF. Importantly, this document also highlights previously used tests that are no longer suggested for PwCF and areas where research is mandated. This collaboration, on behalf of the European Cystic Fibrosis Society Exercise Working Group, represents expert consensus by a multidisciplinary panel of physiotherapists, exercise scientists and clinicians and aims to improve global standardisation of functional exercise testing of PwCF. In short, the standardised use of a small selection of tests performed to a high standard is advocated.

Retrospective cohort analysis of weight changes during the COVID-19 pandemic in a pediatric asthma population.

OBJECTIVE: To investigate the BMI trajectories of children attending a tertiary asthma clinic during the COVID-19 pandemic. METHODS: Data were collected retrospectively on children and young people with asthma who attended the Royal Hospital for Children and Young People (RHCYP) before March 2020 (pre-COVID-19) and after August 2021 (the lifting of national restrictions). MAIN OUTCOME MEASURES: Changes in weight, height, and BMI Z score measured between 13/03/2019 and 13/03/2020 (timepoint 1) and then again during the period 01/08/2021 to 01/10/2022 (timepoint 2); changes in lung function parameters (FEV1) between the timepoints; proportion of study sample classed as obese and overweight at both timepoints; interaction analyses according to deprivation indices (SIMD decile), the use of high dose inhaled corticosteroid (ICS) therapy, and the presence of atopy. RESULTS: Eighty-nine children aged 5-18 years were studied. Weight and height Z scores significantly increased between timepoint 1 and 2 [weight Z score: +0.19 (0.08, +0.30), height Z score: +0.15 (+0.07, +0.23)], such that no significant change was observed in the BMI Z score [+ 0.07 (-0.05, +0.20)] or BMI centile [+0.5 (-3.1, +4.1)]. There was also no change in FEV1%predicted [-0.1 (-3.8, +3.6)] between the timepoints. CONCLUSIONS: No changes in BMI were observed in children with asthma before and after COVID-19 lockdowns. Improved linear growth was noted, implying an improvement in the overall physical health of our study cohort. This may suggest improved asthma control, which may reflect avoidance of viral triggers and/or improved adherence to treatment.

Survey of exercise testing and training in cystic fibrosis clinics in the UK: a decade of progress.

OBJECTIVES: Regular exercise testing is recommended for people with cystic fibrosis (pwCF), as is the provision and regular review of exercise training programmes. A previous survey on exercise testing and training for pwCF in the UK was conducted over a decade ago. With the landscape of CF changing considerably during this time, this survey aimed to evaluate UK-based exercise testing and training practices for pwCF a decade on. DESIGN: Cross-sectional, online survey. PARTICIPANTS: A survey was distributed electronically to UK CF clinics and completed by the individual primarily responsible for exercise services. Descriptive statistics and qualitative analyses were undertaken. RESULTS: In total, 31 CF centres participated, representing ~50% of UK specialist clinics. Of these, 94% reported using exercise testing, 48% of which primarily use cardiopulmonary exercise testing. Exercise testing mostly occurs at annual review (93%) and is most often conducted by physiotherapists (62%). A wide variation in protocols, exercise modalities, normative reference values and cut-offs for exercise-induced desaturation are currently used. All centres reportedly discuss exercise training with pwCF; 94% at every clinic appointment. However, only 52% of centres reportedly use exercise testing to inform individualised exercise training. Physiotherapists typically lead discussions around exercise training (74%). CONCLUSIONS: These data demonstrate that the majority of respondent centres in the UK now offer some exercise testing and training advice for pwCF, representing a marked improvement over the past decade. However, continued efforts are now needed to standardise exercise practices, particularly regarding field testing practices and the translation of test results into personalised training programmes for pwCF.

Systematic review and meta-analysis: Associations of vitamin D with pulmonary function in children and young people with cystic fibrosis.

BACKGROUND: Increasing evidence suggests that vitamin D is associated with pulmonary health, which may benefit children and young people diagnosed with Cystic Fibrosis (cypCF). Therefore, the aim of this systematic review was to evaluate primary research to establish associations between 25OHD and pulmonary health in cypCF. METHODS: Electronic databases were searched with keywords related to CF, vitamin D, children/young people and pulmonary function. Included studies were cypCF (aged ≤21 years) treated in a paediatric setting. The primary outcome was lung function [forced expiratory volume in 1 s (FEV1% predicted)] and secondary outcomes were rate of pulmonary exacerbations, 25OHD status and growth. Evidence was appraised for risk of bias using the CASP tool, and quality using the EPHPP tool. A Meta-analysis was performed. RESULTS: Twenty-one studies were included with mixed quality ratings and heterogeneity of reported outcomes. The Meta-analysis including 5 studies showed a significantly higher FEV1% predicted in the 25OHD sufficiency compared to the deficiency group [FEV1% predicted mean difference (95% CI) was 7.71 (1.69-13.74) %; p = 0.01]. The mean ± SD FEV1% predicted for the sufficient (≥75 nmol/L) vs. deficient (<50 nmol/L) group was 94.7 ± 31.9% vs. 86.9 ± 13.2%; I2 = 0%; χ2 = 0.5; df = 4). Five studies (5/21) found significantly higher rate of pulmonary exacerbations in those who were 25OHD deficient when compared to the sufficient group and negative associations between 25OHD and FEV% predicted. The effects of vitamin D supplementation dosages on 25OHD status (10/21) varied across studies and no study (12/21) showed associations between 25OHD concentration and growth. CONCLUSION: This systematic review suggests that 25OHD concentration is positively associated with lung function and a concentration of >75 nmol/L is associated with reduced frequency of pulmonary exacerbations, which may slow lung function decline in cypCF. Future randomised clinical trials and mechanistic studies are warranted.

Cystic fibrosis related diabetes is not associated with maximal aerobic exercise capacity in cystic fibrosis: a cross-sectional analysis of an international multicenter trial.

BACKGROUND: Previous studies have reported differences in aerobic exercise capacity, expressed as peak oxygen uptake (VO2peak), between people with and without cystic fibrosis (CF) related diabetes (CFRD). However, none of the studies controlled for the potential influence of physical activity on VO2peak. We investigated associations between CFRD and VO2peak following rigorous control for confounders including objectively measured physical activity. METHODS: Baseline data from the international multicenter trial ACTIVATE-CF with participants ≥12 years performing up to 4 h per week of vigorous physical activity were used for this project. Multivariable models were computed to study associations between CFRD and VO2peak (mL.min-1) adjusting for a set of pre-defined covariates: age, sex, weight, forced expiratory volume in 1 s (FEV1), breathing reserve index, Pseudomonas aeruginosa infection, and physical activity (aerobic step counts from pedometry). Variables were selected based on their potential confounding effect on the association between VO2peak and CFRD. RESULTS: Among 117 randomized individuals, 103 (52% female) had a maximal exercise test and were included in the analysis. Participants with (n = 19) and without (n = 84) CFRD did not differ in FEV1, physical activity, nutritional status, and other clinical characteristics. There were also no differences in VO2peak (mL.min-1 or mL.kg-1.min-1 or% predicted). In the final multivariable model, all pre-defined covariates were significant predictors of VO2peak (mL.min-1), however CFRD [coefficient 82.1, 95% CI -69.5 to 233.8, p = 0.28] was not. CONCLUSIONS: This study suggests no meaningful differences in VO2peak between people with and without CFRD given comparable levels of physical activity.

The Exeter Activity Unlimited statement on physical activity and exercise for cystic fibrosis: methodology and results of an international, multidisciplinary, evidence-driven expert consensus.

BACKGROUND: The roles of physical activity (PA) and exercise within the management of cystic fibrosis (CF) are recognised by their inclusion in numerous standards of care and treatment guidelines. However, information is brief, and both PA and exercise as multi-faceted behaviours require extensive stakeholder input when developing and promoting such guidelines. METHOD: On 30th June and 1st July 2021, 39 stakeholders from 11 countries, including researchers, healthcare professionals and patients participated in a virtual conference to agree an evidence-based and informed expert consensus about PA and exercise for people with CF. This consensus presents the agreement across six themes: (i) patient and system centred outcomes, (ii) health benefits, iii) measurement, (iv) prescription, (v) clinical considerations, and (vi) future directions. The consensus was achieved by a stepwise process, involving: (i) written evidence-based synopses; (ii) peer critique of synopses; (iii) oral presentation to consensus group and peer challenge of revised synopses; and (iv) anonymous voting on final proposed synopses for adoption to the consensus statement. RESULTS: The final consensus document includes 24 statements which surpassed the consensus threshold (>80% agreement) out of 30 proposed statements. CONCLUSION: This consensus can be used to support health promotion by relevant stakeholders for people with CF.

The impact of COVID-19 upon the delivery of exercise services within cystic fibrosis clinics in the United Kingdom.

OBJECTIVES: The COVID-19 pandemic has resulted in unprecedent changes to clinical practice, and as the impact upon delivery of exercise services for people with cystic fibrosis (CF) in the United Kingdom was unknown, this was characterised via a national survey. METHODS: An electronic survey was distributed to healthcare professionals involved in the exercise management of CF via established professional networks. RESULTS: In total, 31 CF centres participated. Findings included significant reductions in exercise testing and widespread adaptation to deliver exercise training using telehealth methods. Promisingly, 71% stated that they would continue using virtual methods of engaging patients in future practice. CONCLUSION: These findings highlight adaptation to the COVID-19 pandemic and the need to develop sustainable and standardised telehealth services to manage patients moving forwards.

Exercise as an Airway Clearance Technique in people with Cystic Fibrosis (ExACT-CF): rationale and study protocol for a randomised pilot trial.

Background: Chest physiotherapy is an established cornerstone of care for people with cystic fibrosis (pwCF), but is often burdensome. Guidelines recommend at least one chest physiotherapy session daily, using various airway clearance techniques (ACTs). Exercise (with huffs and coughs) may offer an alternative ACT, however the willingness of pwCF to be randomised into a trial needs testing. The 'ExACT-CF: Exercise as an Airway Clearance Technique in people with Cystic Fibrosis' trial will test the feasibility of recruiting pwCF to be randomised to continue usual care (chest physiotherapy) or replace it with exercise ACT (ExACT) for 28-days. Secondary aims include determining the short-term clinical impact (and safety) of stopping routine chest physiotherapy and replacing it with ExACT, and effects on physical activity, sleep, mood, quality of life and treatment burden, alongside preliminary health economic measures and acceptability. Methods: Multi-centre, two-arm, randomised (1:1 allocation using minimisation), pilot trial at two sites. Fifty pwCF (≥10 years, FEV 1 >40% predicted, stable on Elexacaftor/Tezacaftor/Ivacaftor (ETI)) will be randomised to an individually-customised ExACT programme (≥once daily aerobic exercise of ≥20-minutes duration at an intensity that elicits deep breathing, with huffs and coughs), or usual care. After baseline assessments, secondary outcomes will be assessed after 28-days, with additional home lung function and exacerbation questionnaires at 7, 14 and 21-days, physical activity and sleep monitoring throughout, and embedded qualitative and health-economic components. Feasibility measures include recruitment, retention, measurement completion, adverse events, interviews exploring the acceptability of trial procedures, and a trial satisfaction questionnaire. Discussion: Co-designed with the UK CF community, the ExACT-CF pilot trial is the first multi-centre RCT to test the feasibility of recruiting pwCF stable on ETI into a trial investigating ExACT. This pilot trial will inform the feasibility, design, management, likely external validity for progression to a main phase randomised controlled trial. Registration: Clinicaltrials.gov ( NCT05482048).

Cystic fibrosis (CF) is the UK's most common inherited genetic condition and affects > 10,500 people. CF causes problems with the movement of salt and water in the body, resulting in sticky mucus building up, mostly in the lungs and gut. Thick mucus in the airways leads to repeated infections which can damage the lungs. Chest physiotherapy is routinely prescribed to keep pwCF healthy, by loosening and clearing sticky, thick mucus from the airways. However, many find it time-consuming and burdensome. People with CF (pwCF) have asked if doing exercise could have the same effect for clearing mucus. Surveys show that many pwCF have occasionally replaced chest physiotherapy with exercise for airway clearance. We also showed that many pwCF, their families, physiotherapists and doctors in the UK consider that hard exercise with huffs and coughs may be able to clear mucus from the airways. We now need to know if they would be willing to take part in research that asks some to stop chest physiotherapy and do intense exercise with huffs and coughs instead. We will study 50 pwCF (> 10 years old) for 28 days. We will ask half to continue their usual care, and half to stop chest physiotherapy and do exercise that gets them breathing deeply (with huffs and coughs) instead. We will see if people are willing to start and continue with such a study and what they think of the processes. We will also see how stopping chest physiotherapy and replacing it with exercise affects measurements of their lung function. Within the study we will talk with pwCF and members of their CF team to understand their experiences. This information will tell us whether a larger study can answer whether certain forms of exercise can safely be used as an alternative to chest physiotherapy.

Effects of a Partially Supervised Conditioning Program in Cystic Fibrosis: An International Multicenter, Randomized Controlled Trial (ACTIVATE-CF).

Rationale: The long-term effects of vigorous physical activity (PA) on lung function in cystic fibrosis are unclear. Objectives: To evaluate effects of a 12-month partially supervised PA intervention using motivational feedback. Methods: In a parallel-arm multicenter randomized controlled trial (ACTIVATE-CF), relatively inactive patients aged at least 12 years were randomly assigned (1:1 ratio) to an intervention group or control group. The intervention group consented to add 3 hours of vigorous PA per week, whereas the control group was asked not to change their PA behavior. Primary endpoint was change in percent predicted FEV1 (ΔFEV1) at 6 months. Secondary endpoints included PA, exercise capacity, exercise motives, time to first exacerbation and exacerbation rates, quality of life, anxiety, depression, stress, and blood glucose control. Data were analyzed using mixed linear models. Measurements and Main Results: A total of 117 patients (40% of target sample size) were randomized to an intervention (n = 60) or control group (n = 57). After 6 months, ΔFEV1 was significantly higher in the control group compared with the intervention group (2.70% predicted [95% confidence interval, 0.13-5.26]; P = 0.04). The intervention group reported increased vigorous PA compared with the control group at each study visit, had higher exercise capacity at 6 and 12 months, and higher PA at 12 months. No effects were seen in other secondary outcomes. Conclusions: ACTIVATE-CF increased vigorous PA and exercise capacity, with effects carried over for the subsequent 6 months, but resulted in better FEV1 in the control group.

Rethinking physical exercise training in the modern era of cystic fibrosis: A step towards optimising short-term efficacy and long-term engagement.

Exercise is considered as an important component of the package of care delivered to people with cystic fibrosis (pwCF). However, despite the well-known short-term physiological and psychological benefits, training effects are heterogenous and the transfer of structured exercise programmes to the daily life of pwCF is challenging. Training concepts and strategies developed over the last decades must be adapted to consider the aging population of pwCF with associated comorbidities, and also a new generation of young pwCF that are healthier than ever. In the present review we propose a new framework for optimising the choice among available exercise training procedures and we provide a theoretical and scientifically justified rationale for considering and testing new exercise training modalities. We propose a multidisciplinary approach, considering various physiological, psychological and logistical factors, with the aim to increase effects of exercise training and build positive long-term exercise behaviour.

The impact of plasma 25-hydroxyvitamin D on pulmonary function and exercise physiology in cystic fibrosis: A multicentre retrospective study.

BACKGROUND: A 25-hydroxyvitamin D (25OHD) may exert immunomodulatory effects on respiratory health, which may translate to improvements in exercise physiology. Thus, we aimed to investigate whether plasma 25OHD is associated with lung function and aerobic fitness in people with cystic fibrosis (pwCF). METHODS: A multicentre retrospective review of pwCF (> 9 years old) attending the Royal Hospital for Sick Children (Edinburgh) or Wessex CF-Unit (Southampton) was performed between July 2017 and October 2019. Demographic and clinical data were collected. Plasma 25OHD measured closest in time to clinical cardiopulmonary exercise testing and/or spirometry [forced expiratory volume (FEV1 )% predicted] was recorded. Pancreatic insufficiency was diagnosed based on faecal elastase of < 100 µg g-1 . We performed multiple-regression analysis with aerobic fitness outcomes [peak oxygen uptake (VO2 peak )] and FEV1 % predicted as primary outcomes. RESULTS: Ninety pwCF [mean ± SD age: 19.1 ± 8.6 years, 54 (60%) children, 48 (53%) males and 88 (98%) Caucasian] were included. 25OHD deficiency and insufficiency was 15 (17%) and 44 (49%), respectively. 25OHD deficiency and insufficiency was significantly associated with pancreatic insufficiency (χ2  = 4.8, p = 0.02). Plasma 25OHD was not significantly associated with FEV1 % predicted (r2  = 0.06, p = 0.42, 95% CI = -0.09 to 0.19) or VO2 peak (r2  = 0.04, p = 0.07, 95% CI = -011 to 0.005) in all pwCF. However, 25OHD was significantly associated with both FEV1 % (r2  = 0.15, p = 0.02, 95% CI = 1.99-2.64) and VO2 peak (r2  = 0.13, p = 0.05, 95% CI = -0.26 to -0.005) in the paediatric cohort. CONCLUSIONS: We showed that 25OHD is associated with improved lung function and aerobic fitness in children and adolescents with CF. Mechanistic and high-quality prospective studies including both lung function and aerobic fitness as primary outcomes are now warranted.

Obstructive sleep apnea syndrome as a rare presentation in a young girl with a central nervous system tumor.

Sleep-related breathing disorders are a common problem in infancy and childhood. The most common type of sleep-related breathing disorder in this age group is obstructive sleep apnea syndrome (OSAS), generally caused by factors affecting airway patency, such as tonsillar hypertrophy or obesity. However, in adults OSAS can also be caused by processes affecting the brainstem, such as central nervous system tumors. This report describes a 2-year-old girl who presented with symptoms of snoring, restless sleep, repeated night-time waking, and apneic events while asleep. She had no comorbidities, and examination revealed normal-sized tonsils. A sleep study demonstrated severe OSAS with an obstructive apnea/hypopnea index of 34. Her OSAS completely resolved on excision of the tumor. The case highlights the importance of neurological examination as part of evaluation of OSAS, especially in cases where tonsils are not enlarged and there are no other risk factors for OSAS. CITATION: Buller F, Kamal MA, Brown SK, et al. Obstructive sleep apnea syndrome as a rare presentation in a young girl with a central nervous system tumor. J Clin Sleep Med. 2022;18(4):1211-1214.

VO2max as an exercise tolerance endpoint in people with cystic fibrosis: Lessons from a lumacaftor/ivacaftor trial.

BACKGROUND: The impact of lumacaftor/ivacaftor on exercise tolerance in people with cystic fibrosis (CF) has not been thoroughly studied. METHODS: We conducted a multisite Phase 4 trial comparing the impact of lumacaftor/ivacaftor on exercise tolerance with that of placebo in participants ≥ 12 years of age with CF homozygous for F508del-CFTR. The primary endpoint was relative change from baseline in maximum oxygen consumption (VO2max) during cardiopulmonary exercise testing (CPET) at Week 24. The key secondary endpoint was relative change from baseline in exercise duration during CPET at Week 24. Other secondary endpoints included changes in other indices of exercise tolerance and changes in CF assessments; safety and tolerability were assessed as an endpoint. RESULTS: Seventy participants were randomized to receive lumacaftor/ivacaftor (n = 34) or placebo (n = 36). The least-squares mean difference for lumacaftor/ivacaftor versus placebo in relative change in VO2max from baseline at Week 24 was -3.2% (95% CI: -9.2, 2.9; P=0.3021); the least-squares mean difference in relative change from baseline in exercise duration at Week 24 was -3.2% (95% CI: -8.0, 1.6). Safety results were consistent with the known lumacaftor/ivacaftor safety profile. CONCLUSIONS: Definitive conclusions regarding the impact of lumacaftor/ivacaftor on exercise tolerance cannot be drawn from these results; however, multicenter studies using CPETs can be reliably performed with multiple time points and conventional methods, provided that calibration can be achieved. Future studies of exercise tolerance may benefit from lessons learned from this study. NCT02875366.

Adaptation to reduced lung function in children and young people with spinal deformity.

BACKGROUND: Severe scoliosis can affect respiratory function in growing patients and produce cardiopulmonary complications, leading to significant morbidity. The development of spinal deformity may impact on young patients' level of function and reported quality of life (QOL). The aim of this study was to investigate the relationship between lung function, exercise capacity and quality of life in young patients with spinal deformity. METHODS: This is a retrospective analysis of 104 patients (31% male, 69% female with mean age 14.9yrs). 77% of patients had an adolescent idiopathic scoliosis, with the remainder having other scoliosis diagnoses or Scheuermann's kyphosis. Principal outcomes included Spirometry [FEV1, FVC], Whole Body Plethysmography, Cardiopulmonary Exercise Testing [CPET] and patient outcome questionnaires (with SRS-22). CPET measures included maximal exercise capacity [VO2peak] as well as VO2 at ventilatory threshold [VT] expressed as %predicted VO2max-a measure of physical conditioning, and minute ventilation [VE] from which breathing reserve [BR] could be calculated. RESULTS: Mean (±SD) main thoracic scoliosis was 59.9° (±15.2°), and mean kyphosis in those with Scheuermann's condition was 95.3° (±11.5°). No correlation was elicited between FEV1 or FVC (%predicted) and VO2peak (%predicted) in this patient cohort. Greater thoracic curves were associated with lower FEV1 (%predicted), r = -0.343, p = 0.001, FVC (%predicted), r = -0.307, p = 0.003 and BR (%) at the end of exercise (r = -0.-0.459, p < 0.001). The patient cohort had a mean (sd) VO2peak of 98(17) %predicted, with greater VO2peak levels recorded in female subjects, those of younger age and those with higher scoliosis angles. Those with better lung function [FEV1 (%predicted)] had better BR (%) at the end of exercise (r = 0.483, p < 0.001). SRS-22 scores correlated significantly with VO2peak (%predicted) (total SRS-22 versus VO2peak (%predicted), r = 0.336, p = 0.002). CONCLUSION: Larger thoracic scoliotic curves are associated with poorer lung function but better exercise capacity, likely related to higher levels of physical conditioning. Higher QOL scores were recorded in patients who had greater VO2peak levels, suggesting that exercise capacity may be a protective factor for emotional well-being in patients with spinal deformity.

ERS statement on standardisation of cardiopulmonary exercise testing in chronic lung diseases.

The objective of this document was to standardise published cardiopulmonary exercise testing (CPET) protocols for improved interpretation in clinical settings and multicentre research projects. This document: 1) summarises the protocols and procedures used in published studies focusing on incremental CPET in chronic lung conditions; 2) presents standard incremental protocols for CPET on a stationary cycle ergometer and a treadmill; and 3) provides patients' perspectives on CPET obtained through an online survey supported by the European Lung Foundation. We systematically reviewed published studies obtained from EMBASE, Medline, Scopus, Web of Science and the Cochrane Library from inception to January 2017. Of 7914 identified studies, 595 studies with 26 523 subjects were included. The literature supports a test protocol with a resting phase lasting at least 3 min, a 3-min unloaded phase, and an 8- to 12-min incremental phase with work rate increased linearly at least every minute, followed by a recovery phase of at least 2-3 min. Patients responding to the survey (n=295) perceived CPET as highly beneficial for their diagnostic assessment and informed the Task Force consensus. Future research should focus on the individualised estimation of optimal work rate increments across different lung diseases, and the collection of robust normative data.

Cardiopulmonary Exercise Testing Provides Additional Prognostic Information in Cystic Fibrosis.

RATIONALE: The prognostic value of cardiopulmonary exercise testing (CPET) for survival in cystic fibrosis (CF) in the context of current clinical management, when controlling for other known prognostic factors, is unclear. OBJECTIVES: To determine the prognostic value of CPET-derived measures beyond peak oxygen uptake ( V. o2peak) following rigorous adjustment for other predictors. METHODS: Data from 10 CF centers in Australia, Europe, and North America were collected retrospectively. A total of 510 patients completed a cycle CPET between January 2000 and December 2007, of which 433 fulfilled the criteria for a maximal effort. Time to death/lung transplantation was analyzed using Cox proportional hazards regression. In addition, phenotyping using hierarchical Ward clustering was performed to characterize high-risk subgroups. MEASUREMENTS AND MAIN RESULTS: Cox regression showed, even after adjustment for sex, FEV1% predicted, body mass index (z-score), age at CPET, Pseudomonas aeruginosa status, and CF-related diabetes as covariates in the model, that V. o2peak in % predicted (hazard ratio [HR], 0.964; 95% confidence interval [CI], 0.944-0.986), peak work rate (% predicted; HR, 0.969; 95% CI, 0.951-0.988), ventilatory equivalent for oxygen (HR, 1.085; 95% CI, 1.041-1.132), and carbon dioxide (HR, 1.060; 95% CI, 1.007-1.115) (all P < 0.05) were significant predictors of death or lung transplantation at 10-year follow-up. Phenotyping revealed that CPET-derived measures were important for clustering. We identified a high-risk cluster characterized by poor lung function, nutritional status, and exercise capacity. CONCLUSIONS: CPET provides additional prognostic information to established predictors of death/lung transplantation in CF. High-risk patients may especially benefit from regular monitoring of exercise capacity and exercise counseling.