High-Flow Nasal Cannula Oxygen Therapy versus Non-Invasive Ventilation in patients at very high risk for extubating failure: A systematic review of randomized controlled trials.

BACKGROUND: Mechanical ventilation is commonly used for managing respiratory failure in chronic obstructive pulmonary disease (COPD) patients, but weaning patients off ventilator support can be challenging and associated with complications. While many patients respond well to Non-invasive ventilation (NIV), a significant proportion may not respond as favourably. We aimed to assess whether high-flow nasal cannula (HFNC) is equally effective as NIV in reducing extubation failure among previously intubated COPD patients. METHODS: This systematic review was carried out in line with PRISMA guidelines We searched PubMed, Scopus, Web of Science, and Cochrane library from inception until February 15, 2023. Randomized Clinical Trials (RCTs) of adults at high risk for extubating failure were included. We examined the use of HFNC as the intervention and NIV as the comparator. Our outcome of interest included, reintubation rate, length of hospital or intensive care unit (ICU) stay, adverse events, and time to reintubation. The Cochrane risk-of-bias tool was used for randomized trials to assess risk of bias. RESULTS: We identified 348 citations, 11 of which were included, representing 2,666 patients. The trials indicate that HFNC is comparable to NIV in preventing reintubation after extubating in COPD patients. In comparison to NIV, HFNC also produced improved tolerance, comfort, and less complications such as airway care interventions. NIV with active humification may be more effective that HFNC in avoiding reintubation in patients who are at extremely high risk for extubating failure. CONCLUSION: The inconclusive nature of emerging evidence highlights the need for additional studies to establish the efficacy and suitability of HFNC as an alternative to NIV for previously intubated COPD patients. Clinicians should consider the available options and individualize their approach based on patient characteristics. Future research should focus on addressing these gaps in knowledge to guide clinical decision-making and optimize outcomes for this patient population.

Whole-course management of chronic obstructive pulmonary disease in primary healthcare: an internet of things-enabled prospective cohort study in China.

BACKGROUND: Despite substantial progress in reducing the global burden of chronic obstructive pulmonary disease (COPD), traditional methods to promote understanding and management of COPD are insufficient. We developed an innovative model based on the internet of things (IoT) for screening and management of COPD in primary healthcare (PHC). METHODS: Electronic questionnaire and IoT-based spirometer were used to screen residents. We defined individuals with a questionnaire score of 16 or higher as high-risk population, COPD was diagnosed according to 2021 Global Initiative for COPD (Global Initiative for Chronic Obstructive Lung Disease) criteria. High-risk individuals and COPD identified through the screening were included in the COPD PHC cohort study, which is a prospective, longitudinal observational study. We provide an overall description of the study's design framework and baseline data of participants. RESULTS: Between November 2021 and March 2023, 162 263 individuals aged over 18 from 18 cities in China were screened, of those 43 279 high-risk individuals and 6902 patients with COPD were enrolled in the cohort study. In the high-risk population, the proportion of smokers was higher than that in the screened population (57.6% vs 31.4%), the proportion of males was higher than females (71.1% vs 28.9%) and in people underweight than normal weight (57.1% vs 32.0%). The number of high-risk individuals increased with age, particularly after 50 years old (χ2=37 239.9, p<0.001). Female patients are more common exposed to household biofuels (χ2=72.684, p<0.05). The majority of patients have severe respiratory symptoms, indicated by a CAT score of ≥10 (85.8%) or an Modified Medical Research Council Dyspnoea Scale score of ≥2 (65.5%). CONCLUSION: Strategy based on IoT model help improve the detection rate of COPD in PHC. This cohort study has established a large clinical database that encompasses a wide range of demographic and relevant data of COPD and will provide invaluable resources for future research.

Analysis of the total serum IgE levels in patients with acute exacerbations chronic obstructive pulmonary disease: A retrospective study.

Currently, few studies have demonstrated the relationship between total serum IgE (T-IgE) and acute exacerbation chronic obstructive pulmonary disease (AECOPD). In this study, T-IgE in AECOPD patients were investigated and jointly analyzed with the clinical characteristics. AECOPD patients hospitalized from July 2018 to July 2019 were included in this study. In this patient cohort, clinical information was investigated. Routine blood tests, C-reactive protein and T-IgE levels of patients were determined along with blood gas analysis. The length of hospital stays, mechanical ventilation during hospitalization, ICU admission, glucocorticoid related clinical information were recorded. A total of 285 AECOPD patients were included in this study, which consisted of a high proportion of males. Of all patients, 49.82% patients exhibited higher T-IgE levels. Based on the reference T-IgE value 60 kU/L, patients were divided into high T-IgE group with T-IgE > 60 kU/L, and low T-IgE group with T-IgE ≤ 60 kU/L. There was no significant difference in the dosage of glucocorticoid between the two groups. Patients in the high T-IgE group had shorter hospital stays and lower probability of mechanical ventilation compared to the low T-IgE group. After adjustment for confounding factors, T-IgE was negatively correlated with the length of hospital stays. AECOPD patients with elevated T-IgE had shorter hospital stays and lower risks of mechanical ventilation and ICU admission. Our results showed that T-IgE might play an important role on evaluating the condition and guiding for treatment decisions in AECOPD patients.

A feeling of not being alone - Patients' with COPD experiences of a group-based self-management education with a digital website: A qualitative study.

AIM: To describe patients' with chronic obstructive pulmonary disease (COPD) experiences of group-based self-management education with a digital website. DESIGN: A qualitative approach with a phenomenologicalmethod. Patients participating in an earlier study, with self-experience of COPD as a special competence, were involved as research partners at the design of this study. METHODS: Eleven individual and two group interviews with five participants in each group were conducted. RESULTS: Group-based self-management education with a digital website supports learning. Sharing experiences with others in similar situations creates security and reduces the feeling of being alone. Based on questions and discussion in the group, and through self-reflection, general information is transformed into useful knowledge and understanding of one's own situation. COPD information on the website provides an opportunity to gain knowledge continuously based on needs that contributes to learning. This research has demonstrated that adapting learning activities to individual learning styles increases sustainability of learning. Sharing experiences reduces feelings of loneliness. It is therefore important to create spaces for sharing experiences and in-depth reflection that support learning over time.

Self-management intervention for patients following hospitalization for acute exacerbation of chronic obstructive pulmonary disease (AECOPD): A pilot randomized controlled trial.

The purpose of this study was to evaluate the handoff guidance (HG) self-management intervention for multimorbid chronic obstructive pulmonary disease (COPD) patients following hospitalization for acute exacerbation of COPD (AECOPD) using HG self-management intervention compared to a control group on COPD self-management outcomes (self-care, self-efficacy, health engagement) and assess feasibility, acceptability, and healthcare utilization. A randomized pilot study used a 2-group with repeated measures design. Adults with COPD who had been hospitalized for AECOPD were recruited. After discharge, the HG self-management intervention employed health coaching delivered at: 1-3, 10-12, and 20-22 days after hospital discharge. Follow-up data collected was collected at 1-3, 10-12, 20-22, 30, 60, and 90 days after hospital discharge. A total of 29 subjects participated, with a mean age of 66 (+8.7) years old, the majority were females (n = 18). Intervention participants reported the acceptability of the HG self-management intervention. Participants in both groups continued to report COPD symptoms after discharge, which decreased over time, although not significantly different by group. The use of COPD maintenance, monitoring, and management behaviors was higher in the treatment group, although not significantly different.

High-flow nasal cannula during pulmonary rehabilitation for people with chronic obstructive pulmonary disease: A systematic review and meta-analysis.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is an increasingly concerning global public health issue due to its high burden of morbidity and mortality. Pulmonary rehabilitation (PR) is a comprehensive intervention to improve patients' physical and psychological conditions, commonly involving oxygen supplementation. The potential benefits of high-flow nasal cannula (HFNC) have recently sparked interest as oxygen therapy. In this context, this study aims to assess the effects of HFNC during the exercise training component of a PR program in people with COPD. METHODS: Systematic review (CRD42022330929). We included randomised controlled trials (RCTs), including crossover RCTs with adults with stable COPD. We included trials using oxygen therapy with HFNC during the exercise training component of a PR programme. PRIMARY OUTCOMES: disease-specific health-related quality of life (HRQoL), exercise capacity (EC) and adverse events. SECONDARY OUTCOMES: treatment adherence, breathlessness and future exacerbations. RESULTS: We included five studies with 300 participants with moderate to severe COPD. The certainty of the evidence was primarily low or very low for all outcomes of interest due to risk of bias, inconsistency or imprecision. HFNC has little to no difference in HRQoL (4 studies, 129 participants, MD 0.17, 95% CI -1.20 to 1.54; I2 50%). HFNC may result in little to no difference in EC (3 studies, 212 participants, mean difference 18.73, 95% CI -20.49 to 28.94; I2 56%), and we are uncertain about the effect of HFNC on breathlessness (4 studies; 244 participants, MD of -0.07, 95% CI -0.4 to 0.26; I2 63%). Only one study with 44 participants reported a participant's withdrawal because of progressive dyspnoea during lower limb exercise. CONCLUSIONS: We are uncertain about the effect of HFNC during the exercise component of a PR programme in HRQoL, EC or dyspnoea compared to usual care or conventional supplementary oxygen. Non-domiciliary oxygen patients showed improvements in HRQoL, EC and dyspnoea.

Improvement of Lung Function by Micronutrient Supplementation in Patients with COPD: A Systematic Review and Meta-Analysis.

BACKGROUND: A healthy, well-balanced diet plays an essential role in respiratory diseases. Since micronutrient deficiency is relatively common in patients with chronic obstructive pulmonary disease (COPD), micronutrient supplementation might have the beneficial health effects in those patients. This systematic review and meta-analysis aimed to demonstrate the impact of micronutrient supplementation on the lung function of patients with COPD. METHODS: The PubMed, Cochrane Library, and Web of Science databases were searched from their corresponding creation until February 2024. Search terms included 'chronic obstructive pulmonary disease', 'COPD', 'micronutrients', 'dietary supplements', 'vitamins', 'minerals', and 'randomized controlled trials'. Meta-analysis was performed to evaluate the effects of micronutrient supplementation alone or complex on lung function in patients with COPD. RESULTS: A total of 43 RCTs fulfilled the inclusion criteria of this study. Meta-analysis revealed that vitamin D supplementation could significantly improve FEV1% (WMDdifferences between baseline and post-intervention (de): 6.39, 95% CI: 4.59, 8.18, p < 0.01; WMDpost-intervention indicators (af): 7.55, 95% CI: 5.86, 9.24, p < 0.01) and FEV1/FVC% (WMDde: 6.88, 95%CI: 2.11, 11.65, WMDaf: 7.64, 95% CI: 3.18, 12.10, p < 0.001), decrease the odds of acute exacerbations, and improve the level of T-cell subsets, including CD3+%, CD4+%, CD8+%, and CD4+/CD8+% (all p < 0.01). The effects of compound nutrients intervention were effective in improving FEV1% (WMDde: 8.38, 95%CI: 1.89, 14.87, WMDaf: 7.07, 95%CI: -0.34, 14.48) and FEV1/FVC% (WMDde: 7.58, 95% CI: 4.86, 10.29, WMDaf: 6.00, 95% CI: 3.19, 8.81). However, vitamin C and vitamin E supplementation alone had no significant effects on lung function (p > 0.05). CONCLUSIONS: Micronutrient supplementation, such as vitamin D alone and compound nutrients, has improved effect on the lung function of patients with COPD. Therefore, proper supplementation with micronutrients would be beneficial to stabilize the condition and restore ventilation function for COPD patients.

[The GOLD (Global Initiative for Chronic Obstructive Lung Disease) 2023 : a substantial revision]. / Le GOLD (Global Initiative for Chronic Obstructive Lung Disease) 2023 : une révision substantielle.

The GOLD is a consensus summarizing current evidence gathered to assess, diagnose and manage patients with chronic obstructive pulmonary disease (COPD). Each year, this GOLD document is enriched with new studies and articles. The year 2023 was special because more than 387 new references were added. These new developments have considerably modified the diagnostic and therapeutic approaches to COPD.

Le GOLD est un consensus résumant les preuves actuelles rassemblées pour évaluer, diagnostiquer et prendre en charge les patients atteints de bronchopneumopathie chronique obstructive (BPCO). Chaque année, ce document GOLD s'enrichit de nouvelles études et articles. L'année 2023 a été particulière puisque plus de 387 nouvelles références ont été ajoutées. Ces nouveautés ont considérablement modifié les approches diagnostique et thérapeutique de la BPCO.

The use of telemedicine in lung diseases with focus on chronic obstructive pulmonary disease.

Telemedicine is emerging and has both clinical, scientific, and political interest. In this review, we present the present literature on implementation and describe the economic considerations when implementing telemedicine in chronic obstructive pulmonary disease (COPD). The use of telemedicine in COPD is well-received by patients, but there is little evidence to suggest its superiority to standard outpatient care or to support better outcomes for patients. Thus, local settings and cost effectiveness should be considered during the implementational process.

An economic evaluation of chronic obstructive pulmonary disease clinical pathway in Saskatchewan, Canada: Data-driven techniques to identify cost-effectiveness among patient subgroups.

BACKGROUND: Saskatchewan has implemented care pathways for several common health conditions. To date, there has not been any cost-effectiveness evaluation of care pathways in the province. The objective of this study was to evaluate the real-world cost-effectiveness of a chronic obstructive pulmonary disease (COPD) care pathway program in Saskatchewan. METHODS: Using patient-level administrative health data, we identified adults (35+ years) with COPD diagnosis recruited into the care pathway program in Regina between April 1, 2018, and March 31, 2019 (N = 759). The control group comprised adults (35+ years) with COPD who lived in Saskatoon during the same period (N = 759). The control group was matched to the intervention group using propensity scores. Costs were calculated at the patient level. The outcome measure was the number of days patients remained without experiencing COPD exacerbation within 1-year follow-up. Both manual and data-driven policy learning approaches were used to assess heterogeneity in the cost-effectiveness by patient demographic and disease characteristics. Bootstrapping was used to quantify uncertainty in the results. RESULTS: In the overall sample, the estimates indicate that the COPD care pathway was not cost-effective using the willingness to pay (WTP) threshold values in the range of $1,000 and $5,000/exacerbation day averted. The manual subgroup analyses show the COPD care pathway was dominant among patients with comorbidities and among patients aged 65 years or younger at the WTP threshold of $2000/exacerbation day averted. Although similar profiles as those identified in the manual subgroup analyses were confirmed, the data-driven policy learning approach suggests more nuanced demographic and disease profiles that the care pathway would be most appropriate for. CONCLUSIONS: Both manual subgroup analysis and data-driven policy learning approach showed that the COPD care pathway consistently produced cost savings and better health outcomes among patients with comorbidities or among those relatively younger. The care pathway was not cost-effective in the entire sample.

Suboptimal peak inspiratory flow rate: a noticeable risk factor for inhaler concordance in patients with chronic airway diseases.

BACKGROUND: Inhaler concordance and the peak inspiratory flow rate (PIFR) are important determinants of treatment effects in patients with chronic airway diseases. Adequate PIFR is required for driving aerosol medication into the lower respiratory tract. However, the relationship between them has not been discussed previously. This study aimed to describe the characteristics of inhaler concordance and PIFR in Chinese patients with chronic airway diseases and discuss the associated variables and the relationship between them. METHODS: In this single-centre, observational study, a total of 680 patients with chronic airway diseases were enrolled from July 2021 to April 2023. We collected data on the socio-demographic and clinical variables of inhaler concordance using the test of adherence to inhalers (TAI) and PIFR. Multivariate logistic regression was conducted to examine variables related to inhaler concordance and PIFR. RESULTS: A total of 49.4% of patients had low concordance. Patients with chronic obstructive pulmonary disease (COPD) were more concordant than patients with asthma (mean TAI score: 43.60 vs 41.20; p<0.01), while there was no difference in concordance between the asthma-COPD overlap group and the asthma or COPD group. Suboptimal PIFR (adjusted OR, 1.61; 95% CI 1.04 to 2.51) increased the risk of poor concordance among all patients, while triple therapy (adjusted OR, 0.60; 95% CI 0.35 to 0.86) reduced the risk. A total of 54.9% of patients had suboptimal PIFR. Older age, lower educational level, use of dry powder inhalers and lower forced expiratory volume in 1 s % predicted were significantly correlated with insufficient PIFR. Subgroup analysis revealed a greater proportion of patients with insufficient PIFR during exacerbation than during the stable phase (61.7% vs 43.5%, p<0.001). CONCLUSION: Inhaler concordance was low, and suboptimal PIFR was a risk factor for poor concordance among Chinese patients with chronic airway diseases. In addition, current inhalation devices may not be suitable, and PIFR reassessment should be considered for patients with COPD during exacerbation. TRIAL REGISTRATION NUMBER: The study was registered in chictr.org.cn (ChiCTR2100052527) on 31 October 2021.

Risk factors of in-hospital mortality and discriminating capacity of NIVO score in exacerbations of COPD requiring noninvasive ventilation.

BACKGROUND: Noninvasive mechanical ventilation (NIV) is recommended as the initial mode of ventilation to treat acute respiratory failure in patients with AECOPD. The Noninvasive Ventilation Outcomes (NIVO) score has been proposed to evaluate the prognosis in patients with AECOPD requiring assisted NIV. However, it is not validated in Chinese patients. METHODS: We used data from the MAGNET AECOPD Registry study, which is a prospective, noninterventional, multicenter, real-world study conducted between September 2017 and July 2021 in China. Data for the potential risk factors of mortality were collected and the NIVO score was calculated, and the in-hospital mortality was evaluated using the NIVO risk score. RESULTS: A total of 1164 patients were included in the study, and 57 patients (4.9%) died during their hospital stay. Multiple logistic regression analysis revealed that age ≥75 years, DBP <60 mmHg, Glasgow Coma Scale ≤14, anemia and BUN >7 mmol/L were independent predictors of in-hospital mortality. The in-hospital mortality was associated with an increase in the risk level of NIVO score and the difference was statistically significant (p < .001). The NIVO risk score showed an acceptable accuracy for predicting the in-hospital mortality in AECOPD requiring assisted NIV (AUC: 0.657, 95% CI: 0.584-0.729, p < .001). CONCLUSION: Our findings identified predictors of mortality in patients with AECOPD receiving NIV, providing useful information to identify severe patients and guide the management of AECOPD. The NIVO score showed an acceptable predictive value for AECOPD receiving NIV in Chinese patients, and additional studies are needed to develop and validate predictive scores based on specific populations.

Modifiable risk factors that may be addressed in routine care to prevent progression to and extension of multimorbidity in people with COPD: a systematic literature review.

Chronic obstructive pulmonary disease (COPD) is a multisystem disease, and many patients have multiple conditions. We explored multimorbidity patterns that might inform intervention planning to reduce health-care costs while preserving quality of life for patients. Literature searches up to February 2022 revealed 4419 clinical observational and comparative studies of risk factors for multimorbidity in people with COPD, pulmonary emphysema, or chronic bronchitis at baseline. Of these, 29 met the inclusion criteria for this review. Eight studies were cluster and network analyses, five were regression analyses, and 17 (in 16 papers) were other studies of specific conditions, physical activity and treatment. People with COPD more frequently had multimorbidity and had up to ten times the number of disorders of those without COPD. Disease combinations prominently featured cardiovascular and metabolic diseases, asthma, musculoskeletal and psychiatric disorders. An important risk factor for multimorbidity was low socioeconomic status. One study showed that many patients were receiving multiple drugs and had increased risk of adverse events, and that 10% of medications prescribed were inappropriate. Many patients with COPD have mainly preventable or modifiable multimorbidity. A proactive multidisciplinary approach to prevention and management could reduce the burden of care.

Effects and long-term outcomes of endurance versus resistance training as an adjunct to standard medication in patients with stable COPD: a multicenter randomized trial.

BACKGROUND: Comparisons between endurance training (ET) and resistance training (RT) have produced equivocal findings in chronic obstructive pulmonary disease (COPD) patients. The purpose of our study is to investigate the effectiveness and long-term outcomes of adding ET and RT to conventional medical treatment in patients with COPD. A secondary objective is to investigate the clinical improvements resulting from exercise training in patients with different disease severities. METHODS: The study was a multicenter, prospective trial in people with stable COPD. The cohort was randomized to three groups: individualized medical treatment group (MT), MT + endurance training group (MT + ET) and MT + resistance training group (MT + RT). Exercise was performed 3 times weekly over a 12-week period. The endpoints of exercise capacity, health-related quality of life, COPD symptoms, lung function, and anxiety and depression questionnaires were re-evaluated at baseline, at the completion of the intervention and at 6 and 12-month follow-up. According to the COPD assessment tool offered by GOLD guidelines, patients were stratified into GOLD A and B groups and GOLD C and D groups for further subgroup analysis. RESULTS: The intention-to-treat (ITT) population included 366 patients, 328 of them completed the study protocol over 12 months (the PP-population). There were no significant differences in the primary outcome, quality of life, between patients who underwent medical treatment (MT) alone, MT + endurance training (MT + ET), or MT + resistance training (MT + RT) at the completion of the intervention, 6-, or 12-month follow-up. Additionally, no significant differences were observed between MT, MT + RT, or MT + ET groups concerning the primary outcome, exercise capacity (3MWD), after initial 3 months of intervention. However, a small statistically significant difference was noted in favor of MT + ET compared to MT + RT at 12 months (ITT: Δ3MWD in ET vs RT = 5.53 m, 95% confidence interval: 0.87 to 13.84 m, P = 0.03) (PP: Δ3MWD in ET vs RT = 7.67 m, 95% confidence interval: 0.93 to 16.27 m, P = 0.04). For patients in the GOLD C and D groups, improvement in quality of life following ET or RT was significantly superior to medical intervention alone. Furthermore, upon completion of the exercise regimen, RT exhibited a greater improvement in anxiety compared to ET in these patients (ITT: ΔHAD-A at 3-month: RT = -1.63 ± 0.31 vs ET = -0.61 ± 0.33, p < 0.01) (PP: ΔHAD-A at 3-month: RT = -1.80 ± 0.36 vs ET = -0.75 ± 0.37, p < 0.01). CONCLUSIONS: Our study presents evidence of the beneficial effects of ET and RT in combination with standard medical treatment, as well as the long-term effects over time after the intervention. While the statistically significant effect favoring ET over RT in terms of exercise capacity was observed, it should be interpreted cautiously. Patients in severe stages of COPD may derive greater benefits from either ET or RT and should be encouraged accordingly. These findings have implications for exercise prescription in patients with COPD. TRIAL REGISTRATION: ChiCTR-INR-16009892 (17, Nov, 2016).

Rate of severe exacerbations, healthcare resource utilisation and clinical outcomes in patients with COPD in low-income and middle-income countries: results from the EXACOS International Study.

INTRODUCTION: The EXAcerbations of Chronic obstructive lung disease (COPD) and their OutcomeS (EXACOS) International Study aimed to quantify the rate of severe exacerbations and examine healthcare resource utilisation (HCRU) and clinical outcomes in patients with COPD from low-income and middle-income countries. METHODS: EXACOS International was an observational, cross-sectional study with retrospective data collection from medical records for a period of up to 5 years. Data were collected from 12 countries: Argentina, Brazil, Chile, Colombia, Costa Rica, Dominican Republic, Guatemala, Hong Kong, Mexico, Panama, Russia and Taiwan. The study population comprised patients ≥40 years of age with COPD. Outcomes/variables included the prevalence of severe exacerbations, the annual rate of severe exacerbations and time between severe exacerbations; change in lung function over time (measured by the forced expiratory volume in 1 s (FEV1)); peripheral blood eosinophil counts (BECs) and the prevalence of comorbidities; treatment patterns; and HCRU. RESULTS: In total, 1702 patients were included in the study. The study population had a mean age of 69.7 years, with 69.4% males, and a mean body mass index of 26.4 kg/m2. The mean annual prevalence of severe exacerbations was 20.1%, and 48.4% of patients experienced ≥1 severe exacerbation during the 5-year study period. As the number of severe exacerbations increased, the interval between successive exacerbations decreased. A statistically significant decrease in mean (SD) FEV1 from baseline to post-baseline was observed in patients with ≥1 severe exacerbation (1.23 (0.51) to 1.13 (0.52) L; p=0.0000). Mean BEC was 0.198 x109 cells/L, with 64.7% of patients having a BEC ≥0.1 x109 cells/L and 21.3% having a BEC ≥0.3 x109 cells/L. The most common comorbidity was hypertension (58.3%). An increasing number of severe exacerbations per year was associated with greater HCRU. DISCUSSION: The findings presented here indicate that effective treatment strategies to prevent severe exacerbations in patients with COPD remain a significant unmet need in low-income and middle-income countries.

20 years of neuromuscular electrical stimulation in COPD.

Although a lung disease, COPD is also associated with extrapulmonary manifestations including, among others, limb muscle dysfunction. Limb muscle dysfunction is a key systemic consequence of COPD that impacts patients' physical activity, exercise tolerance, quality of life and survival. Deconditioning is the main mechanism underlying the development of limb muscle dysfunction in COPD, which can be partially improved with exercise. However, some patients may not be able to tolerate exercise because of incapacitating breathlessness or unwillingness to undertake whole-body exercise. Alternative training modalities that do not give rise to dyspnoea, such as neuromuscular electrical stimulation (NMES), are urged. Over the past 20 years, NMES in COPD has presented conflicting conclusions in meta-analysis. In this review, we try to understand the reason for this result by analysing possible biases and factors that brought conflicting conclusions. We discuss the population (the intervention group, but also the control group), the outcome measures, the frequency of stimulation, the rehabilitation protocol (i.e. NMES alone versus standard care/rehabilitation or NMES plus conventional exercise training versus conventional exercise training alone or NMES versus sham treatment) and the trial design. The main reason for this discrepancy is the lack of dedicated guidelines for NMES. Further research is urged to determine the optimal parameters for an NMES programme. Despite this, NMES appears to be an effective means of enhancing quadriceps strength and exercise capacity in COPD with the potential to break the vicious circle induced by the disease and COPD patients' lifestyle.

MAIT cells are associated with responsiveness to neoadjuvant immunotherapy in COPD-associated NSCLC.

BACKGROUND: Patients with non-small cell lung cancer (NSCLC) and chronic obstructive pulmonary disease (COPD) experience worse clinical outcomes but respond better to immunotherapy than patients with NSCLC without COPD. Mucosal-associated invariant T (MAIT) cells, a versatile population of innate immune T lymphocytes, have a crucial function in the response to infection and tumors. This study investigated the distribution of MAIT cells in COPD-associated NSCLC and their involvement in the immune response. METHODS: Flow cytometry, immunohistochemistry, and immunofluorescence were performed on tissue samples of patients with NSCLC, with or without COPD, treated with or without anti-programmed death 1 (PD1) immunotherapy. MAIT cells were stimulated with 5-OP-RU using a mouse subcutaneous tumor model. RESULTS: Tumors contained significantly more MAIT cells than paraneoplastic tissues, and CD8+ MAIT cells accounted for more than 90% of these cells. Patients with NSCLC and COPD had higher CD8+ MAIT cell counts than those with NSCLC without COPD. Additionally, patients with NSCLC and COPD displayed reduced expression of the activation marker, CD69, and functional markers, granzyme B (GZMB) and interferon γ (IFNγ), and higher expression of the immune exhaustion marker, PD1. Among patients who received immunotherapy, the proportion with a complete or partial response was higher in those with COPD than in those without COPD. In patients with NSCLC and COPD, the major pathologic response (MPR) group had higher MAIT levels than those in the no major pathologic response (NPR) group. In the mouse subcutaneous tumor model stimulation of MAIT cells using 5-OP-RU enhanced the antitumor effects of anti-PD1. CONCLUSIONS: In patients with NSCLC and COPD, response to immunotherapy is associated with accumulation of CD8+ MAIT cells showing immune exhaustion. These findings may contribute to innovative approaches for immunotherapy targeting CD8+ MAIT cells.