The presence of extra-pulmonary treatable traits increases the likelihood of responding to pulmonary rehabilitation

INTRODUCTION

Studies suggest that people with chronic obstructive pulmonary disease (COPD) who are worse at baseline respond better to pulmonary rehabilitation (PR). Identifying treatable traits (TTs) may help to distinguish responders from non-responders. We explored the impact of PR on extra-pulmonary traits of people with COPD and whether the presence of TT influences the type of response to PR.

METHODS

A comprehensive assessment of 9 TT including symptoms (dyspnoea, fatigue, anxiety and depression), functional capacity, deconditioning, balance, impact of the disease and health-related quality of life was conducted before and after a 12-week community-based PR programme. Pre-post differences between people with or without each TT at baseline were compared with independent samples t-tests or Mann-Whitney U tests. Proportion of responders between groups were explored with chi-square tests and odds ratio.

RESULTS

102 people with COPD were included (70 [65; 75] years old, 78% male, FEV₁ 47 [36; 60] %predicted). They had a median of 3 (out of 9) TTs per person and each patient responded on average to 5 (out of 9) outcomes of PR. People with TT were more responsive than those without them in all outcomes (p < 0.05) except for the 1-min sit-to-stand test. The presence of TT increased 4 to 20 times the likelihood of being a good responder.

CONCLUSIONS

Identification of baseline extra-pulmonary TT in people with COPD showed the potential to inform on PR responsiveness and might therefore be an important strategy for patient prioritization, treatment personalisation (i.e., activation of the most suitable components) and optimisation.

Short-Term Oxygen Therapy Outcomes in COPD

Rationale

Short-term oxygen therapy (STOT) is often prescribed to allow patients with chronic obstructive pulmonary disease (COPD) to be discharged safely from hospital following an acute illness. This practice is widely accepted without being based on evidence.

Purpose

Our objective was to describe the characteristics and outcomes of patients with COPD who received STOT.

Patients and Methods

The study was a secondary analysis of the INOX trial, a 4-year randomised trial of nocturnal oxygen in COPD. The trial indicated that nocturnal oxygen has no significant effect on survival or progression to LTOT, allowing our merging of patients who received nocturnal oxygen and those who received placebo into a single cohort to study the predictors and outcomes of STOT regardless of the treatment received during the trial.

Results

Among the 243 participants in the trial, 60 required STOT on at least one occasion during follow-up. Patients requiring STOT had more severe dyspnoea and lung function impairment, and lower PaO₂ at baseline than those who did not. STOT was associated with subsequent LTOT requirement (hazard ratio [HR]: 4.59; 95% confidence interval [CI]: 2.98–7.07) and mortality (HR: 1.93; 95% CI: 1.15–3.24). The association between STOT and mortality was confounded by age, disease severity and comorbidities. Periods of STOT of more than one month and/or repeated prescriptions of STOT increased the probability of progression to LTOT (OR: 5.07; 95% CI: 1.48–18.8).

Conclusion

Following an acute respiratory illness in COPD, persistent hypoxaemia requiring STOT is a marker of disease progression towards the requirement for LTOT.

The effects of inspiratory muscle training in adults with muscular dystrophy

Background/Aims Patients with muscular dystrophy usually have impaired lung function and respiratory muscle strength, leading to pneumonia and respiratory failure, which are significant causes of morbidity and mortality. Inspiratory muscle training might be a safe adjunct treatment to increase the strength and endurance of weakened respiratory muscles. The researchers have developed a new protocol for inspiratory muscle training and evaluated its effect on inspiratory muscle strength and coughing capacity.

Methods A total of 12 participants diagnosed with muscle dystrophy and decreased maximal inspiratory pressure (<60 cmH2O) participated in this prospective study. Training was individually tailored, starting with low resistance levels and progressing according to tolerance and symptoms. The primary outcome measure was maximal inspiratory pressure. Secondary outcomes were maximal expiratory pressure, peak cough flow and the feasibility of the intervention.

Results There were two participants who did not complete the study, and three were lost to follow-up; therefore, only seven patients finished the intervention. In these patients, the authors found a statistically significant improvement in the maximal inspiratory pressure (P=0.018) and peak cough flow (P=0.046) after 3 months of training. There was also an improvement in the maximal expiratory pressure, although this was not statistically significant (P=0.176). Median compliance to training was 99% (94.5–100).

Conclusions This intervention led to statistically significant improvements in inspiratory muscles strength and coughing capacity in patients with muscular dystrophy. The results were significantly positive and contribute to the evidence in support of this underused, yet possibly beneficial, treatment, although larger randomised controlled trials are required to verify this.

Monthly Follow-Ups of Functional Status in People with COPD: A Longitudinal Study

Functional status is an important and meaningful outcome in people with chronic obstructive pulmonary disease (COPD), although its measurement is not embedded in routine clinical assessments. This study described the functional status of people with COPD using the 1-min sit-to-stand test (1minSTS) over a 6-month period and the examined sociodemographic and clinical characteristics associated with this outcome. Data from a prospective study including people with COPD were analyzed. Functional status was assessed monthly with the 1minSTS over 6 months. Linear-mixed effect models assessed the 1minSTS number of repetitions mean change. One-hundred and eight participants (82.4% men; 66.9 ± 9.5 years) were included. A significantly lower number of repetitions in the 1minSTS over the 6-month period was associated with being female (estimate: −4.69, 95%CI: −8.20; −1.18), being older (estimate: −0.56, 95%CI: −0.77; −0.34), having higher BMI (estimate: −0.55, 95%CI: −0.81; −0.28) and having higher activity-related dyspnea (estimate: −2.04, 95%CI: −3.25; −0.83). Half of the participants showed improvements above three repetitions in the 1minSTS over the 6-month period, independently of their baseline impairment (1minSTS < 70% predicted: 52.5%; ≥70% predicted: 54.4%). To conclude, monthly follow-up assessments were associated with clinically relevant benefits in the functional status of people with COPD. Age, body composition, and activity-related dyspnea were the main predictors of functional status over time. Further research is needed to corroborate our findings and to support the beneficial effects of regular COPD monitoring.

Evaluation of the genetic risk for COVID-19 outcomes in COPD and differences among worldwide populations

Background

Populations seem to respond differently to the global pandemic of severe acute respiratory syndrome coronavirus 2. Recent studies show individual variability in both susceptibility and clinical response to COVID-19 infection. People with chronic obstructive pulmonary disease (COPD) constitute one of COVID-19 risk groups, being already associated with a poor prognosis upon infection. This study aims contributing to unveil the underlying reasons for such prognosis in people with COPD and the variability in the response observed across worldwide populations, by looking at the genetic background as a possible answer to COVID-19 infection response heterogeneity.

Methods

SNPs already associated with susceptibility to COVID-19 infection (rs286914 and rs12329760) and severe COVID-19 with respiratory failure (rs657152 and rs11385942) were assessed and their allelic frequencies used to calculate the probability of having multiple risk alleles. This was performed on a Portuguese case-control COPD cohort, previously clinically characterized and genotyped from saliva samples, and also on worldwide populations (European, Spanish, Italian, African, American and Asian), using publicly available frequencies data. A polygenic risk analysis was also conducted on the Portuguese COPD cohort for the two mentioned phenotypes, and also for hospitalization and survival to COVID-19 infection.

Findings

No differences in genetic risk for COVID-19 susceptibility, hospitalization, severity or survival were found between people with COPD and the control group (all p-values > 0.01), either considering risk alleles individually, allelic combinations or polygenic risk scores. All populations, even those with European ancestry (Portuguese, Spanish and Italian), showed significant differences from the European population in genetic risk for both COVID-19 susceptibility and severity (all p-values < 0.0001).

Conclusion

Our results indicate a low genetic contribution for COVID-19 infection predisposition or worse outcomes observed in people with COPD. Also, our study unveiled a high genetic heterogeneity across major world populations for the same alleles, even within European sub-populations, demonstrating the need to build a higher resolution European genetic map, so that differences in the distribution of relevant alleles can be easily accessed and used to better manage diseases, ultimately, safeguarding populations with higher genetic predisposition to such diseases.

How well do covariates perform when adjusting for sampling bias in online COVID-19 research? Insights from multiverse analyses

COVID-19 research has relied heavily on convenience-based samples, which-though often necessary-are susceptible to important sampling biases. We begin with a theoretical overview and introduction to the dynamics that underlie sampling bias. We then empirically examine sampling bias in online COVID-19 surveys and evaluate the degree to which common statistical adjustments for demographic covariates successfully attenuate such bias. This registered study analysed responses to identical questions from three convenience and three largely representative samples (total N = 13,731) collected online in Canada within the International COVID-19 Awareness and Responses Evaluation Study ( www.icarestudy.com ). We compared samples on 11 behavioural and psychological outcomes (e.g., adherence to COVID-19 prevention measures, vaccine intentions) across three time points and employed multiverse-style analyses to examine how 512 combinations of demographic covariates (e.g., sex, age, education, income, ethnicity) impacted sampling discrepancies on these outcomes. Significant discrepancies emerged between samples on 73% of outcomes. Participants in the convenience samples held more positive thoughts towards and engaged in more COVID-19 prevention behaviours. Covariates attenuated sampling differences in only 55% of cases and increased differences in 45%. No covariate performed reliably well. Our results suggest that online convenience samples may display more positive dispositions towards COVID-19 prevention behaviours being studied than would samples drawn using more representative means. Adjusting results for demographic covariates frequently increased rather than decreased bias, suggesting that researchers should be cautious when interpreting adjusted findings. Using multiverse-style analyses as extended sensitivity analyses is recommended.

Treatable Traits in COPD - A Proposed Approach

The well-recognized individual heterogeneity within COPD patients has led to a growing interest in greater personalization in the approach of these patients. Thus, the treatable traits strategy has been proposed as a further step towards precision medicine in the management of chronic airway disease, both in stable phase and acute exacerbations. The aim of this paper is to perform a critical review on the treatable traits strategy and propose a guide to approach COPD patients in the light of this new concept. An innovative stepwise approach is proposed - a multidisciplinary model based on two distinct phases, with the potential to be implemented in both primary care and hospital settings. The first phase is the initial and focused assessment of a selected subset of treatable traits, which should be addressed in all COPD patients in both settings (primary care and hospital). As some patients may present with advanced disease at diagnosis or may progress despite this initial treatment requiring a more specialized assessment, they should progress to a second phase, in which a broader approach is recommended. Beyond stable COPD, we explore how the treatable traits strategy may be applied to reduce the risk of future exacerbations and improve the management of COPD exacerbations. Since many treatable traits have already been related to exacerbation risk, the strategy proposed here represents an opportunity to be proactive. Although it still lacks prospective validation, we believe this is the way forward for the future of the COPD approach.

Responsiveness and Minimal Clinically Important Difference of the Brief-BESTest in People With COPD After Pulmonary Rehabilitation

OBJECTIVE

he Brief-Balance Evaluation Systems Test (Brief-BESTest) is a comprehensive, reliable, and valid balance test that provides valuable information to guide balance training in people with chronic obstructive pulmonary disease (COPD). Its clinical interpretability is, however, currently limited, because cutoff points to identify clinically relevant changes in people with COPD after pulmonary rehabilitation are still lacking. This study aimed to establish the responsiveness and minimal clinically important difference (MCID) for the Brief-BESTest in people with COPD after pulmonary rehabilitation (PR).

METHODS

A secondary analysis of data from 2 previous studies was conducted. The modified British Medical Research Council (mMRC) dyspnea scale, the 6-Minute Walk Test (6-MWT), and the Brief-BESTest (0-24 points) were collected in people with COPD pre/post a 12-week PR program including balance training. The MCID was computed using anchor- and distribution-based methods. Changes in the 6-MWT and the mMRC were assessed and used as anchors. The pooled MCID was computed using the arithmetic weighted mean (2/3 anchor- and 1/3 distribution-based methods).

RESULTS

Seventy-one people with COPD (69 years [SD = 8]; 76% male; FEV1 = 49.8%predicted [SD = 18%]) were included. There was a significant improvement in the Brief-BESTest after PR (mean difference = 3 points [SD = 3]). Significant correlations were found between the Brief-BESTest and the mMRC (r = -.31) and the 6-MWT (r = .37). The pooled MCID was 3.3 points.

CONCLUSION

An improvement of at least 3 points in the Brief-BESTest in people with COPD will enhance the interpretability of PR effects on balance performance of this population and guide tailored interventions.

IMPACT

The Brief-BESTest outcome measure is comprehensive, easily administered, and simple to interpret in clinical practice. This study represents a significant contribution toward the clinical interpretation of changes in balance in people with COPD following PR.

Inspiratory muscle training in neuromuscular patients: Assessing the benefits of a novel protocol

BACKGROUND

Neuromuscular diseases are characterized by the compromise of respiratory muscles, thoracic ventilation, muscle strength and coughing capacity. Patients have low quality of life and increased morbidity and mortality mostly due to respiratory impairment.

OBJECTIVE

To assess the benefits of adding inspiratory muscle training to neuromuscular patients' treatment and their compliance to the approach.

METHODS

We conducted a single-center prospective study with neuromuscular patients with decreased maximal inspiratory pressure. We developed an inspiratory muscle training protocol with three-month duration and once-daily training. The protocol had a progressive intensity that was individually tailored based on patients' baseline characteristics and tolerance. We used Powerbreathe Medic Classic devices to perform the training.

RESULTS

There were 21 patients who met the inclusion criteria and were enrolled in the study. Muscular dystrophy (n= 12, 57.3%) and amyotrophic lateral sclerosis (n= 4, 19%) were the most common diseases. After three months of training, patients increased their maximal inspiratory muscle pressure (p= 0.002) and peak cough flow (p= 0.011). Compliance to the protocol was 99 ± 5.5%.

CONCLUSIONS

This protocol showed significant improvements on pulmonary muscles function and might be considered as an adjunct treatment to neuromuscular treatment. However, these positive results require larger further studies to validate the clinical benefits long-term.

Follow-up loss in smoking cessation consultation: can we predict and prevent it?

Background

Cigarette smoking has a considerable health and economic burden in modern society, with increased risk of morbidity and mortality. Therefore, smoking cessation policies and medical treatments are essential. However, cessation rates are low and the abandonment of the consultation is common. The identification of characteristics that may predict adherence will help defining the best treatment strategy. This study aimed to identify predictors of follow-up loss in smoking cessation consultation.

Methods

We made a retrospective observational study, including a cohort of patients who started smoking cessation consultation (April-December 2018). Clinical data from consultations was collected and analyzed with IBM SPSS Statistics (SPSS, RRID:SCR_002865).

Results

A total of 175 patients was selected (41.1% female), with a mean age of 53±12 years. Eighty-five patients (48.6%) were discharged for abandonment. They had a median pack-year unit 38±36 (P=0.011), Fagerström and Richmond scores of 5±2 and 7±2, respectively. There was an association between women (P<0.001), younger age (P<0.001), depression/anxiety (P=0.023), lower smoking load (P=0.019), starting the treatment in the first appointment (P=0.004) and the abandonment of the consultation. In binary logistic regression, younger age (less than 50 years) (OR =4.39; 95% CI: 1.99-9.70), starting the treatment in the first appointment (OR =3.04; 95% CI: 1.44-6.42) and depression/anxiety (OR =2.30; 95% CI: 1.08-4.88) remained independent predictors of loss in follow-up.

Conclusions

Women, younger age, depression/anxiety, lower smoking load and starting treatment in the first appointment are predictors of follow-up loss, so, these patients may benefit from more frequent evaluations and intensive cognitive approach. This study also raises awareness about the adequate timing to start pharmacological support for smoking cessation.

Minimal Clinically Important Difference for Quadriceps Muscle Strength in People with COPD following Pulmonary Rehabilitation

Quadriceps strength training is a key component of pulmonary rehabilitation (PR). Clinical interpretability of changes in muscle strength following PR is however limited due to the lack of cut-off values to define clinical improvement. This study estimated the minimal clinically important difference (MCID) for the isotonic and isometric quadriceps muscle strength assessed with the one-repetition maximum (1RM) and hand-held dynamometry (HHD) in people with chronic obstructive pulmonary disease (COPD) following PR.A secondary analysis of a real life non-randomised controlled study was conducted in people with COPD enrolled in a 12-week community-based PR programme. Anchor and distribution-based methods were used to compute the MCIDs. The anchors explored were the St. George's respiratory questionnaire (SGRQ) and the six-minute walk test (6MWT) using Pearson's correlations. Pooled MCIDs were computed using the arithmetic weighted mean (2/3 anchor, 1/3 distribution-based methods) and reported as absolute and/or percentage of change values.Eighty-nine people with COPD (84% male, 69.9 ± 7.9 years, FEV₁ 49.9 ± 18.9% predicted) were included. No correlations were found between changes in 1RM and the SGRQ neither between changes in HHD and the SGRQ and 6MWT (p > 0.05). Thus, anchor-based methods were used only in the MCID of the 1RM with the 6MWT as the anchor. The pooled MCIDs were 5.7Kg and 26.9% of change for the isotonic quadriceps muscle strength with 1RM and 5.2KgF for isometric quadriceps muscle strength assessed with HHD.The MCIDs found are estimates to improve interpretability of community-based PR effects on quadriceps muscle strength and may contribute to guide interventions.

Is the 1-Minute Sit-To-Stand Test a Good Tool to Evaluate Exertional Oxygen Desaturation in Chronic Obstructive Pulmonary Disease?

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is frequently associated with exertional oxygen desaturation, which may be evaluated using the 6-minute walking test (6MWT). However, it is a time-consuming test. The 1-minute sit-to-stand test (1STST) is a simpler test, already used to evaluate the functional status. The aim of this study was to compare the 1STST to the 6MWT in the evaluation of exertional desaturation.

METHODS

This was a cross-sectional study including 30 stable COPD patients who performed the 6MWT and 1STST on the same day. Six-minute walking distance (6MWD), number of 1STST repetitions (1STSTr), and cardiorespiratory parameters were recorded.

RESULTS

A significant correlation was found between the 6MWD and the number of 1STSTr (r = 0.54; p = 0.002). The minimum oxygen saturation (SpO₂) in both tests showed a good agreement (intraclass correlation coefficient (ICC) 0.81) and correlated strongly (r = 0.84; p < 0.001). Regarding oxygen desaturation, the total agreement between the tests was 73.3% with a fair Cohen´s kappa (κ = 0.38; p = 0.018), and 93.33% of observations were within the limits of agreement for both tests in the Bland-Altman analysis.

CONCLUSION

The 1STST seems to be a capable tool of detecting exercise-induced oxygen desaturation in COPD. Because it is a less time- and resources-consuming test, it may be applied during the outpatient clinic consultation to regularly evaluate the exercise capacity and exertional desaturation in COPD.

Randomized Trial of Nocturnal Oxygen in Chronic Obstructive Pulmonary Disease

BACKGROUND

Long-term oxygen therapy improves survival in patients with chronic obstructive pulmonary disease (COPD) and chronic severe daytime hypoxemia. However, the efficacy of oxygen therapy for the management of isolated nocturnal hypoxemia is uncertain.

METHODS

We designed this double-blind, placebo-controlled, randomized trial to determine, in patients with COPD who have nocturnal arterial oxygen desaturation without qualifying for long-term oxygen therapy, whether nocturnal oxygen provided for a period of 3 to 4 years would decrease mortality or the worsening of disease such that patients meet current specifications for long-term oxygen therapy. Patients with an oxygen saturation of less than 90% for at least 30% of the recording time on nocturnal oximetry were assigned, in a 1:1 ratio, to receive either nocturnal oxygen or ambient air from a sham concentrator (placebo). The primary outcome was a composite of death from any cause or a requirement for long-term oxygen therapy as defined by the Nocturnal Oxygen Therapy Trial (NOTT) criteria in the intention-to-treat population.

RESULTS

Recruitment was stopped prematurely because of recruitment and retention difficulties after 243 patients, of a projected 600, had undergone randomization at 28 centers. At 3 years of follow-up, 39.0% of the patients assigned to nocturnal oxygen (48 of 123) and 42.0% of those assigned to placebo (50 of 119) met the NOTT-defined criteria for long-term oxygen therapy or had died (difference, -3.0 percentage points; 95% confidence interval, -15.1 to 9.1).

CONCLUSIONS

Our underpowered trial provides no indication that nocturnal oxygen has a positive or negative effect on survival or progression to long-term oxygen therapy in patients with COPD. (Funded by the Canadian Institutes of Health Research; INOX ClinicalTrials.gov number, NCT01044628.).

Improving access to community-based pulmonary rehabilitation: 3R protocol for real-world settings with cost-benefit analysis

Background

Pulmonary rehabilitation (PR) has demonstrated patients’ physiological and psychosocial improvements, symptoms reduction and health-economic benefits whilst enhances the ability of the whole family to adjust to illness. However, PR remains highly inaccessible due to lack of awareness of its benefits, poor referral and availability mostly in hospitals. Novel models of PR delivery are needed to enhance its implementation while maintaining cost-efficiency. We aim to implement an innovative community-based PR programme and assess its cost-benefit.

Methods

A 12-week community-based PR will be implemented in primary healthcare centres where programmes are not available. Healthcare professionals will be trained. 73 patients with CRD and their caregivers (dyads patient-caregivers) will compose the experimental group. The control group will include dyads age- and disease-matched willing to collaborate in data collection but not in PR. Patients/family-centred outcomes will be dyspnoea (modified Medical Research Council Questionnaire), fatigue (Checklist of individual strength and Functional assessment of chronic illness therapy – fatigue), cough and sputum (Leicester cough questionnaire and Cough and sputum assessment questionnaire), impact of the disease (COPD Assessment Test), emotional state (The Hospital Anxiety and Depression Scale), number of exacerbations, healthcare utilisation, health-related quality of life and family adaptability/cohesion (Family Adaptation and Cohesion Scale). Other clinical outcomes will be peripheral (biceps and quadriceps-hand held dynamometer, 1 or 10 repetition-maximum) and respiratory (maximal inspiratory and expiratory pressures) muscle strength, muscle thickness and cross sectional area (biceps brachialis, rectus femoris and diaphragm-ultrasound imaging), exercise capacity (six-minute walk test and one-minute sit to stand test), balance (brief-balance evaluation systems test) and physical activity (accelerometer). Data will be collected at baseline, at 12 weeks, at 3- and 6-months post-PR.

Changes in the outcome measures will be compared between groups, after multivariate adjustment for possible confounders, and effect sizes will be calculated. A cost-benefit analysis will be conducted.

Discussion

This study will enhance patients access to PR, by training healthcare professionals in the local primary healthcare centres to conduct such programmes and actively involving caregivers. The cost-benefit analysis of this intervention will provide an evidence-based insight into the economic benefit of community-based PR in chronic respiratory diseases.

Trial registration

The trial was registered in the ClinicalTrials.gov U.S. National Library of Medicine, on 10th January, 2019 (registration number: NCT03799666).

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7045-1) contains supplementary material, which is available to authorized users.

Prevalence of bronchial obstruction in a tobacco smoke exposed population - the PNEUMOBIL project

The use of spirometry is not yet widespread enough in chronic respiratory or at -risk patients whose diagnosis is incomplete. There is scarce knowledge and inadequate management of the burden of these diseases, particularly chronic obstructive pulmonary disease (COPD). Pneumobil, an initiative aimed at raising awareness among smokers and ex -smokers, was reactivated 10 years after its launch in Portugal. It found a large prevalence of bronchial obstruction as measured by spirometry (30% and 25% in men and women respectively) in a sample of 5324 smoke -exposed individuals, 50% current smokers, screened at state or business (private company group) health institutions. This risk is neither mainly attributable to occupational exposure nor mainly related to respiratory symptoms, which were very common in our population. Only dyspnoea (OR=1.28; p=0.02) and frequent episodes of sputum production (OR=1.21; p=0.008) or acute bronchitis (OR=1.31; p=0.05) were somewhat related to bronchial obstruction. Prior knowledge of COPD is rare and bronchial obstruction is not correlated (p=0.204) to a possible diagnosis of COPD.