Executive Summary: 2017 ERS/ATS standards for single-breath carbon monoxide uptake in the lung

Evaluating performance on the Glittre-ADL test in men with long COVID 3 years after a SARS-CoV-2 infection

Background/objective

Many COVID-19 survivors, especially those who have been hospitalized, have been suffering numerous complications that limit their activities of daily living, although changes that persist 3 years after infection are still not known. We aimed to investigate the impact of long COVID on the Glittre-ADL test (TGlittre) 3 years after acute infection in men who needed hospitalization and explore whether the performance on the TGlittre is associated with impairments in lung function, muscle strength, physical function and quality of life (QoL).

Methods

Cross-sectional study with 42 men with long COVID who took the TGlittre. They underwent pulmonary function tests and measurements of handgrip strength and quadriceps strength (QS). Additionally, they also completed the Saint George Respiratory Questionnaire (SGRQ) and Functional Independence Measure (FIM).

Results

The mean age was 52 ± 10.6 years, while the mean time after diagnosis of COVID-19 was 37 ± 3.5 months. The mean TGlittre time was 3.3 (3.1-4.1) min, which was 10% greater than the time expected for normal individuals to complete it. The TGlittre time was correlated significantly with the QS (rs = -0.397, p = 0.009), pulmonary diffusion (rs = - 0.364, p = 0.017), FIM (rs = -0.364, p = 0.017) and the "activity" domain score of the SGRQ (rs = 0.327, p = 0.034).

Conclusion

Functional capacity on exertion as measured by the TGlittre time is normal in most men with long COVID 3 years after hospitalization. However, this improvement in functional capacity does not seem to be reflected in muscle strength or QoL, requiring continued monitoring even after 3 years.

Use of 6-minute walk distance to predict lung transplant-free survival in fibrosing non-IPF interstitial lung diseases

BACKGROUND AND OBJECTIVE

The identification of progression in patients with fibrosing non-idiopathic pulmonary fibrosis (IPF) interstitial lung diseases (ILDs) represents an ongoing clinical challenge. Lung function decline alone may have significant limitations in the detection of clinically significant progression. We hypothesized that longitudinal changes of 6-min walk distance (6MWD) from baseline, simultaneously considered with measures of lung function, may independently predict survival and identifying clinically significant progression of disease.

METHODS

Forced vital capacity (FVC), diffusing lung capacity (DLCO) and 6MWD were considered both at baseline and at 1 year in a discovery cohort (n = 105) and in a validation cohort (n = 138) from different centres. The primary endpoint was lung transplant (LTx)-free survival.

RESULTS

Average follow-up was 3 years in both cohorts. Combined incidence of deaths and LTx was 29% and 21%, respectively. No collinearity and no strong correlations were observed among FVC, DLCO and 6MWD longitudinal changes. While age, gender and BMI were not significant, 6MWD decline ≥24 m predicted LTx-free-survival significantly and independently from FVC and DLCO declines, with high sensitivity and specificity, in both the discovery and the validation cohorts. Although FVC and DLCO declines remained significant predictors of LTx-free survival, 6MWD decline was more accurate than the proposed ATS/ERS/JRS/ALAT functional criteria. Results were confirmed after stratifying patients by baseline FVC.

CONCLUSION

Longitudinal declines of 6MWD are associated with poor survival in fibrosing ILDs across a wide range of baseline severity, with high accuracy. 6MWD longitudinal decline is largely independent from lung function decline and may be integrated into the routine assessment of progression.

Association between serum uric acid levels and lung function in the NHANES cohort (2007-2012): A cross-sectional analysis of a diverse American population

BACKGROUND

Hyperuricemia has been linked to various health conditions. However, the relationship between uric acid (UA) levels and lung function remains debated.

METHODS

In a cross-sectional study of 6750 participants aged 20-69 from NHANES, we assessed UA levels and lung function (FVC and FEV1). We conducted regression analyses while adjusting for potential confounders.

RESULTS

After accounting for factors like age, sex, BMI, smoking, and more, we found a negative association between UA FVC and FEV1. Specifically, for every 0.1 mg/dL increase in UA, FEV1 decreased by 15.265 mL, and FVC decreased by 24.46 mL. No association was observed with FEV1/FVC. Subgroup analyses revealed similar negative correlations among various groups, particularly in non-Hispanic Black females under 60.

CONCLUSION

Serum UA levels are inversely associated with FEV1 and FVC in the American population, with a notable impact on non-Hispanic Black females under 60.

Referential equations for pulmonary diffusing capacity generated from the Japanese population using the Lambda, Mu, or Sigma method and their comparisons with prior referential equations

BACKGROUND

This study aimed to establish reference equations for single-breath lung carbon monoxide diffusing capacity (DLCO), alveolar volume (VA), and transfer coefficient of the lungs for carbon monoxide (KCO, sometimes written as DLCO/VA) in the Japanese population. A generalised additive model for location size and shape (GAMLSS) was used to build each equation.

METHODS

To collect pulmonary function data throughout a broad age range, we prospectively obtained pulmonary function data from healthy volunteers and retrospectively obtained data from patients with normal diffusing capacity aged 16-85 years.

RESULTS

In total, 702 tests were conducted. The validation group z-scores, except for DLCO in males, showed substantial discrepancies between the Global Lung Initiative (GLI) baseline prediction equations and the present study's prediction equations, indicating the need for a new reference value prediction approach. The root mean square errors of the DLCO, VA, and KCO reference values obtained from the present study's prediction equations were lower than those derived from the GLI and previous linear regression equations.

CONCLUSIONS

Reference values obtained in this study were more appropriate for our sample than those derived from the existing baseline prediction equations. This research's contribution is the development of a more precise prediction equation that can be used to establish a reference value range for pulmonary diffusing capacity.

ETHICS AND DISSEMINATION

This research does not include any dissemination plan (publications, data deposition and curation).

Sex-specific difference in cardiac function in patients with systemic sclerosis: association with cardiovascular outcomes

BACKGROUND

Cardiovascular involvement is one of the leading causes of mortality in systemic sclerosis (SSc) and is reported to be higher in men as compared with women. However, the cause of this difference is largely unknown. The objective of this study was to assess sex differences in echocardiographic characteristics, including left ventricular global longitudinal strain (LV GLS), as a potential explanation of sex differences in outcomes.

METHODS

A total of 746 patients with SSc from four centres, including 628 (84%, 54±13 years) women and 118 (16%, 55±15 years) men, were evaluated with standard and advanced echocardiographic examinations. The independent association of the echocardiographic parameters with the combined endpoint of cardiovascular events-hospitalisation/death was evaluated.

RESULTS

Men and women with SSc showed significant differences in disease characteristics and cardiac function. After adjusting for the most important clinical characteristics, while LV ejection fraction and diastolic function were not significantly different anymore, men still presented with more impaired LV GLS as compared with women (-19% (IQR -20% to -17%) vs -21% (IQR: -22% to -19%), p<0.001). After a median follow-up of 48 months (IQR: 26-80), the combined endpoint occurred in 182 patients. Men with SSc experienced higher cumulative rates of cardiovascular events-hospitalisation/mortality (χ2=8.648; Log-rank=0.003), and sex differences were maintained after adjusting for clinical confounders, but neutralised when matching the groups for LV GLS.

CONCLUSION

In patients with SSc, male sex is associated with worse cardiovascular outcomes even after adjusting for important clinical characteristics. LV GLS was more impaired in men as compared with women and potentially explains the sex difference in cardiovascular outcomes.

Lung function at 16-19 years in males and females born very prematurely

OBJECTIVES

To determine if there were differences in lung function at 16-19 years of age between males and females born very prematurely.

WORKING HYPOTHESIS

Females compared with males would have superior lung function and exercise capacity.

STUDY DESIGN

Cohort study.

PATIENT-SUBJECT SELECTION

Those born at less than 29 weeks of gestational age.

METHODOLOGY

Lung function testing (spirometry, oscillometry, diffusion capacity, lung clearance index, and plethysmography), a shuttle sprint test for exercise capacity, and a respiratory symptoms questionnaire.

RESULTS

Amongst 150 participants, males had poorer lung function compared with females with mean z score differences (95% CI [confidence interval]) after adjustment: forced expiratory flow at 75% (FEF₇₅ ) (-0.60 [-0.97,-0.24]), forced expiratory flow at 50% (FEF₅₀ ) (-0.39 [-0.72,-0.07]), forced expiratory flow at 25%-75% (FEF_25-75 ) (-0.62 [-0.98,-0.26]), the ratio of the forced expiratory volume in the first one second to the forced vital capacity of the lungs (FEV₁ :FVC ratio) (-0.71 [-1.09,-0.34]), diffusing capacity of the lungs for carbon monoxide (DLCO) (-0.41 [-0.78,-0.03]), diffusing capacity of the lung for carbon monoxide divided by alveolar volume (DLCO/VA) (-0.57 [-0.86,-0.28]). Exercise capacity and self-reported exercise were both significantly better in males than females (46% males achieving between 1250 and 1500 m shuttle sprint distance vs. 4.8% females) and 74% males versus 67% females undertaking some exercise. There were no significant differences by sex in the prevalence of either wheeze or current asthma.

CONCLUSIONS

Males had poorer lung function than females at age 16-19 years, but their exercise capacity was superior to females.

Chemo-Radio-Immunotherapy for NSCLC III: ESR/ATS Thresholds for DLCO Correlate with Radiation Dosimetry and Pneumonitis Rate

Introduction: Durvalumab following chemoradiotherapy (CRT) for non-small cell lung cancer stage III has become the standard of care (SoC) in the past few years. With this regimen, 5-year overall survival (OS) has risen to 43%. Therefore, adequate pulmonary function (PF) after treatment is paramount in long-term survivors. In this respect, carbon monoxide diffusing capacity (DLCO), which represents the alveolar compartment, seems to be a suitable measure for residual lung capacity. The aim of the current analysis was to correlate DLCO with pneumonitis and radiation dose. Patients and methods: One hundred and twelve patients with histologically confirmed NSCLC III treated between 2015/10 and 2022/03 were eligible for this study. Patients received two cycles of platinum-based induction chemotherapy followed by high-dose radiotherapy (RT). As of 2017/09, durvalumab maintenance therapy was administered for one year. The clinical endpoints were based on the thresholds jointly published by the European Respiratory Society (ERS) and the American Thoracic Society (ATS). Pre-treatment DLCO of 60% was correlated to the incidence of pneumonitis, whereas the post-treatment DLCO decline of 10% was related to radiation dose. Results: Patients with a pre-treatment DLCO < 60% had a higher probability of pneumonitis (n = 98; r = 0.175; p-value 0.042), which could be reproduced in the subgroup of patients who did not receive durvalumab (n = 40; r = 0.288; p-value 0.036). In these individuals, the decline in DLCO ≥ 10% depended significantly on the size of the lung volume receiving between 45% and 65% (V65–45%) of the total radiation dose (r = 0.354; p-value = 0.020) and V20 Total Lung (r = 0.466; corrected p-value = 0.042). Conclusions: The current analysis revealed that DLCO is a predictor for clinically relevant pneumonitis and a monitoring tool for post-treatment lung function as it correlates with radiation dose. This underlines the importance of peri-treatment lung function testing.

Association between serum uric acid/serum creatinine ratios and lung function in the general American population: National Health and Nutrition Examination Survey (NHANES), 2007-2012

BACKGROUND

Assessment of lung function is essential for the early screening chronic airway diseases (CADs). Nevertheless, it is still not widely used for early diagnosing CADs in epidemiological or primary care settings. Thus, we used data from the US National Health and Nutrition Examination Survey (NHANES) to discuss the relationship between the serum uric acid/serum creatinine (SUA/SCr) ratio and lung function in general adults to gain the role of SUA/SCr in early assessment of lung function abnormalities.

METHODS

From 2007 to 2012 NHANES, a total of 9569 people were included in our study. Using the regression model, XGBoost algorithm model, generalised linear model and two-piecewise linear regression model, the link between the SUA/SCr ratio and lung function was investigated.

RESULTS

After correcting for confounding variables, the data revealed that forced vital capacity (FVC) declined by 47.630 and forced expiratory volume in one second (FEV1) decreased by 36.956 for each additional unit of SUA/SCr ratio. However, there was no association between SUA/SCr and FEV1/FVC. In the XGBoost model of FVC, the top five most important were glycohaemoglobin, total bilirubin, SUA/SCr, total cholesterol and aspartate aminotransferase, whereas in FEV1, were glycohaemoglobin, total bilirubin, total cholesterol, SUA/SCr and serum calcium. In addition, we determined the linear and inverse association between SUA/SCr ratio and FVC or FEV1 by constructing a smooth curve.

CONCLUSIONS

In the general American population, the SUA/SCr ratio is inversely linked with FVC and FEV1, but not with FEV1/FVC, according to our research. Future studies should investigate the impact of SUA/SCr on lung function and identify possible mechanisms of action.

Association Between Chronic Obstructive Pulmonary Disease and All-Cause Mortality After Aortic Valve Replacement for Aortic Stenosis

Chronic obstructive pulmonary disease (COPD) and aortic stenosis (AS) are the most common diseases in which age plays a major role in the increase of their prevalence and when they co-exist, the outcomes prognosis worsens significantly. The aim of the present study was to evaluate the association between pulmonary functional parameters and all-cause mortality after aortic valve replacement (transcatheter or surgical). A total of 400 patients with severe AS and preoperative pulmonary functional test were retrospectively analyzed. Echocardiography and pulmonary functional parameters before aortic valve replacement were collected. COPD severity was defined according to criteria from the Society of Thoracic Surgeons. COPD was present in 128 patients (32%) with severe AS. Patients without COPD had smaller left ventricular (LV) mass and LV end-systolic volume and better LV function than the group with COPD. During a median follow-up of 32 months, 92 patients (23%) died. The survival rates were significantly lower in patients with moderate and severe COPD (log-rank p = 0.003). In the multivariable Cox regression analysis, any grade of COPD was associated with an approximately 2-fold increased risk of all-cause mortality (hazard ratio 1.933; 95% confidence interval 1.166 to 3.204; p = 0.011 for mild COPD and hazard ratio 2.028; 95% confidence interval 1.154 to 3.564; p = 0.014 for moderate or severe COPD). In addition to other clinical factors, any grade of COPD was associated with 2-fold increased risk of all-cause mortality.

Prevalence of reduced lung diffusing capacity and CT scan findings in smokers without airflow limitation: a population-based study

BACKGROUND

Population distribution of reduced diffusing capacity of the lungs for carbon monoxide (DLCO) in smokers and main consequences are not properly recognised. The objectives of this study were to describe the prevalence of reduced DLCO in a population-based sample of current and former smoker subjects without airflow limitation and to describe its morphological, functional and clinical implications.

METHODS

A sample of 405 subjects aged 40 years or older with postbronchodilator forced expiratory volume in 1 s/forced vital capacity (FVC) >0.70 was obtained from a random population-based sample of 9092 subjects evaluated in the EPISCAN II study. Baseline evaluation included clinical questionnaires, exhaled carbon monoxide (CO) measurement, spirometry, DLCO determination, 6 min walk test, routine blood analysis and low-dose CT scan with evaluation of lung density and airway wall thickness.

RESULTS

In never, former and current smokers, prevalence of reduced DLCO was 6.7%, 14.4% and 26.7%, respectively. Current and former smokers with reduced DLCO without airflow limitation were younger than the subjects with normal DLCO, and they had greater levels of dyspnoea and exhaled CO, greater pulmonary artery diameter and lower spirometric parameters, 6 min walk distance, daily physical activity and plasma albumin levels (all p<0.05), with no significant differences in other chronic respiratory symptoms or CT findings. FVC and exhaled CO were identified as independent risk factors for low DLCO.

CONCLUSION

Reduced DLCO is a frequent disorder among smokers without airflow limitation, associated with decreased exercise capacity and with CT findings suggesting that it may be a marker of smoking-induced early vascular damage.

TRIAL REGISTRATION NUMBER

NCT03028207.

ERS/ATS technical standard on interpretive strategies for routine lung function tests

BACKGROUND

Appropriate interpretation of pulmonary function tests (PFTs) involves the classification of observed values as within/outside the normal range based on a reference population of healthy individuals, integrating knowledge of physiological determinants of test results into functional classifications and integrating patterns with other clinical data to estimate prognosis. In 2005, the American Thoracic Society (ATS) and European Respiratory Society (ERS) jointly adopted technical standards for the interpretation of PFTs. We aimed to update the 2005 recommendations and incorporate evidence from recent literature to establish new standards for PFT interpretation.

METHODS

This technical standards document was developed by an international joint Task Force, appointed by the ERS/ATS with multidisciplinary expertise in conducting and interpreting PFTs and developing international standards. A comprehensive literature review was conducted and published evidence was reviewed.

RESULTS

Recommendations for the choice of reference equations and limits of normal of the healthy population to identify individuals with unusually low or high results are discussed. Interpretation strategies for bronchodilator responsiveness testing, limits of natural changes over time and severity are also updated. Interpretation of measurements made by spirometry, lung volumes and gas transfer are described as they relate to underlying pathophysiology with updated classification protocols of common impairments.

CONCLUSIONS

Interpretation of PFTs must be complemented with clinical expertise and consideration of the inherent biological variability of the test and the uncertainty of the test result to ensure appropriate interpretation of an individual's lung function measurements.

Peripheral Neuropathy in Patients Recovering from Severe COVID-19: A Case Series

Background and Objectives: Neurological manifestations have been reported in a significant proportion of coronavirus disease 2019 (COVID-19) patients. We aimed to evaluate the prevalence and severity of peripheral nervous system (PNS) involvement in a large group of convalescent COVID-19 patients undergoing in-hospital multidisciplinary rehabilitation. Materials and Methods: Convalescent COVID-19 patients admitted to a Pulmonary Rehabilitation Unit were consecutively screened for inclusion within 48 h of discharge from an acute care setting. All included patients underwent electrophysiological examinations. Results: Among 102 enrolled patients (mean age 62.0 years, 82.4% males), PNS electrophysiological alterations were detected in 42.2%. Mononeuropathies exclusively involving the peroneal nerve were observed in 8.8% (n = 9), while multiple mononeuropathies were similarly reported in nine patients (8.8%). A symmetric sensorimotor polyneuropathy was documented in 24.5% of participants (n = 25). A significant difference was found for exercise capacity and pulmonary function in post hoc comparisons between the three study groups. Conclusions: The risk of neuropathy in the convalescent phase of COVID-19 is relevant. This should be considered when planning multidisciplinary rehabilitation strategies.

T Lymphocyte Maturation Profile in the EBUS-TBNA Lymph Node Depending on the DLCO Parameter in Patients with Pulmonary Sarcoidosis

Sarcoidosis (SA) is a systemic granulomatous disorder of unknown etiology with lung and mediastinal lymph nodes (LNs) as the main location. T lymphocytes play important role in the formation of granulomas in SA, but still little is known about the role of maturation profile in the development of inflammatory changes. The aim of this study was to determine the CD4+ and CD8+ T cells maturation profile in LNs and in peripheral blood (PB) and its relation to disease severity expressed by diffusing capacity of the lung for carbon monoxide (DLCO). 29 patients with newly pulmonary SA were studied. Flow cytometry was used for cells evaluation in EBUS-TBNA samples. We observed lower median proportion of T lymphocytes, CD4+ T and CD8+ T cells in patients with DLCO< 80% than in patients with normal diffusion (DLCO > 80%). Patients with DLCO < 80% had lower median proportion of effector and higher median proportion of central memory CD4+ and CD8+ T cells than patients with DLCO > 80%. We reported for the first time that LNs CD4+ and CD8+ T cells maturation differs depending on the DLCO value in sarcoidosis. Lymphocytes profiles in LNs may reflect the immune status of patients with SA and can be analysed by flow cytometry of EBUS-TBNA samples.

Circulating white blood cells and lung function impairment: the observational studies and Mendelian randomization analysis

BACKGROUND

Circulating white blood cell (WBC) counts have been related to lung function impairment, but causal relationship was not established. We aimed to evaluate independent effects and causal relationships of WBC subtypes with lung function.

METHODS

The 19,159 participants from NHANES 2011-2012 (n = 3570), coke-oven workers (COW, n = 1762) and Dongfeng-Tongji (DFTJ, n = 13,827) cohorts were included in the observational studies. The associations between circulating counts of WBC subtypes and prebronchodilator lung function were evaluated by linear regression models and LASSO regression was used to select effective WBC subtypes. Summary statistics for WBC-associated SNPs were extracted from literature, and Mendelian randomization (MR) analysis with inverse-variance weighted (IVW) method was applied to estimate the causal effects of total WBC and subtypes on lung function among 4012 subjects from COW (n = 1126) and DFTJ cohorts (n = 2886).

RESULTS

Total WBC counts were negatively associated with lung function among three populations and their pooled analysis indicated that per 1 × 109 cells/L increase in total WBC was associated with 36.13 (95% CI: 30.35, 41.91) mL and 25.23 (95% CI: 19.97, 30.50) mL decrease in FVC and FEV1, respectively. Independent associations with lung function were found for neutrophils, monocytes, eosinophils and basophils (all p < .05), except lymphocytes. Besides, IVW MR analysis showed that genetically predicted total WBC and neutrophil counts were associated with reduced FVC (p = .017 and .021, respectively) and FEV1 (p = .048 and .043, respectively).

CONCLUSIONS

WBC subtypes were independently associated with lower lung function except lymphocytes. Our findings suggest that circulating neutrophils may be causal factors in lung function impairment.KEY MESSAGESWhite blood cell (WBC) subtypes were negatively associated with lung function level except lymphocytes in the observational studies.Associations of WBC subtypes with lung function may be modified by sex and smoking.Mendelian randomization analysis shows that neutrophils may be causal factors in lung function impairment.

Six-Month Pulmonary Impairment after Severe COVID-19: A Prospective, Multicentre Follow-Up Study

BACKGROUND

Long-term pulmonary sequelae following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia are not yet confirmed; however, preliminary observations suggest a possible relevant clinical, functional, and radiological impairment.

OBJECTIVES

The aim of this study was to identify and characterize pulmonary sequelae caused by SARS-CoV-2 pneumonia at 6-month follow-up.

METHODS

In this multicentre, prospective, observational cohort study, patients hospitalized for SARS-CoV-2 pneumonia and without prior diagnosis of structural lung diseases were stratified by maximum ventilatory support ("oxygen only," "continuous positive airway pressure," and "invasive mechanical ventilation") and followed up at 6 months from discharge. Pulmonary function tests and diffusion capacity for carbon monoxide (DLCO), 6-min walking test, chest X-ray, physical examination, and modified Medical Research Council (mMRC) dyspnoea score were collected.

RESULTS

Between March and June 2020, 312 patients were enrolled (83, 27% women; median interquartile range age 61.1 [53.4, 69.3] years). The parameters that showed the highest rate of impairment were DLCO and chest X-ray, in 46% and 25% of patients, respectively. However, only a minority of patients reported dyspnoea (31%), defined as mMRC ≥1, or showed restrictive ventilatory defects (9%). In the logistic regression model, having asthma as a comorbidity was associated with DLCO impairment at follow-up, while prophylactic heparin administration during hospitalization appeared as a protective factor. The need for invasive ventilatory support during hospitalization was associated with chest imaging abnormalities.

CONCLUSIONS

DLCO and radiological assessment appear to be the most sensitive tools to monitor patients with the coronavirus disease 2019 (COVID-19) during follow-up. Future studies with longer follow-up are warranted to better understand pulmonary sequelae.

Secondary polycythemia in chronic obstructive pulmonary disease: prevalence and risk factors

BACKGROUND

Secondary polycythemia is associated with cigarette smoking and chronic obstructive pulmonary disease (COPD). However, the prevalence of polycythemia in COPD and the contributing risk factors for polycythemia in COPD have not been extensively studied.

METHODS

We analyzed the presence of secondary polycythemia in current and former smokers with moderate to very severe COPD at the five-year follow-up visit in the observational COPDGene study. We used logistic regression to evaluate the association of polycythemia with age, sex, race, altitude, current smoking status, spirometry, diffusing capacity for carbon monoxide (DLCO), quantitative chest CT measurements (including emphysema, airway wall thickness, and pulmonary artery to aorta diameter ratio), resting hypoxemia, exercise-induced hypoxemia, and long-term oxygen therapy.

RESULTS

In a total of 1928 COPDGene participants with moderate to very severe COPD, secondary polycythemia was found in 97 (9.2%) male and 31 (3.5%) female participants. In a multivariable logistic model, severe resting hypoxemia (OR 3.50, 95% CI 1.41-8.66), impaired DLCO (OR 1.28 for each 10-percent decrease in DLCO % predicted, CI 1.09-1.49), male sex (OR 3.60, CI 2.20-5.90), non-Hispanic white race (OR 3.33, CI 1.71-6.50), current smoking (OR 2.55, CI 1.49-4.38), and enrollment in the Denver clinical center (OR 4.42, CI 2.38-8.21) were associated with higher risk for polycythemia. In addition, continuous (OR 0.13, CI 0.05-0.35) and nocturnal (OR 0.46, CI 0.21-0.97) supplemental oxygen were associated with lower risk for polycythemia. Results were similar after excluding participants with anemia and participants enrolled at the Denver clinical center.

CONCLUSIONS

In a large cohort of individuals with moderate to very severe COPD, male sex, current smoking, enrollment at the Denver clinical center, impaired DLCO, and severe hypoxemia were associated with increased risk for secondary polycythemia. Continuous or nocturnal supplemental oxygen use were associated with decreased risk for polycythemia.

Markers of inflammation and immune activation are associated with lung function in a multi-center cohort of persons with HIV

OBJECTIVES

Studies have shown that people with HIV (PWH) may be at increased risk for chronic lung diseases and lung function abnormalities, which may be associated with immune activation. We tested the association of a panel of 12 immune activation and inflammation biomarkers with spirometry and single-breath diffusing capacity for carbon monoxide (DLco).

DESIGN

Cross-sectional, observational study.

METHODS

Participants were enrolled from the Inflammation, Aging, Microbes and Obstructive Lung Disease cohort of PWH at two US sites. Biomarkers were examined and standardized spirometry and DLco testing were performed. We tested associations between each biomarker and lung function, examined individually and in combination, using multi-variable linear and logistic regression.

RESULTS

Among 199 participants, median forced expiratory volume in 1 s (FEV1) was normal (90% predicted) and median DLco was abnormal (69% predicted). The most common lung function abnormality (57%) was a normal FEV1 to forced vital capacity ratio with an abnormal DLco of 80% or less predicted (iso↓DLco). Two markers (IL-6, high-sensitivity C-reactive protein) were associated with FEV1% predicted, whereas eight markers (soluble CD14, soluble CD163, inducible protein-10, soluble CD27, IL-6, soluble tumor necrosis factor receptors 1 and 2, D-dimer) were associated with DLco% predicted. Compared with those participants with normal spirometry and DLco, five markers (soluble CD14, soluble CD163, interferon gamma inducible protein-10, soluble tumor necrosis factor receptors 1 and 2) were associated with iso↓DLco.

CONCLUSION

Among PWH, different markers of immune activation and inflammation are associated with FEV1% predicted than with DLco% predicted and with an iso↓DLco, representing possible unique pathways of chronic lung disease. Identifying plausible drivers of these inflammatory pathways may clarify mechanisms underlying impaired lung function in HIV infection and may identify therapeutic avenues.

Preexisting cardiorespiratory comorbidity does not preclude the success of multidisciplinary rehabilitation in post-COVID-19 patients

Patients recovering from coronavirus disease 2019 (COVID-19) may not return to a pre-COVID functional status and baseline levels of healthcare needs after discharge from acute care hospitals. Since the long-term outcomes of COVID-19 can be more severe in patients with underlying cardiorespiratory diseases, we aimed at verifying the impact of a preexisting cardiorespiratory comorbidity on multidisciplinary rehabilitation in post-COVID-19 patients. We enrolled 95 consecutive patients referring to the Pulmonary Rehabilitation Unit of Istituti Clinici Scientifici Maugeri Spa SB, IRCCS of Telese Terme, Benevento, Italy after being discharged from the COVID-19 acute care ward and after recovering from acute COVID-19 pneumonia. Forty-nine of them were not suffering from underlying comorbidities, while 46 had a preexisting cardiorespiratory disease. Rehabilitation induced statistically significant improvements in respiratory function, blood gases and the ability to exercise both in patients without any preexisting comorbidities and in those with an underlying cardiorespiratory disease. Response to the rehabilitation cycle tended to be greater in those without preexisting comorbidities, but DLco%-predicted was the only parameter that showed a significant greater improvement when compared to the response in the group of patients with underlying cardiorespiratory comorbidity. This study suggests that multidisciplinary rehabilitation may be useful in post-COVID-19 patients regardless of the presence of preexisting cardiorespiratory comorbidities.

Serum Acylglycerols Inversely Associate with Muscle Oxidative Capacity in Severe COPD

PURPOSE

Chronic obstructive pulmonary disease (COPD) is associated with altered metabolism and body composition that accompany poor outcomes. We aimed to determine whether metabolic derangements in COPD are associated with skeletal muscle deconditioning and/or physical inactivity, independent of pulmonary obstruction.

METHODS

We characterized serum metabolites associated with muscle oxidative capacity or physical activity in 44 COPD patients (forced expiratory volume in 1 s [FEV1] = 61% ± 4% predicted) and 63 current and former smokers with normal spirometry (CON) (FEV1 = 93% ± 2% predicted). Medial gastrocnemius oxidative capacity was assessed at rest from the recovery rate constant (k) of muscle oxygen consumption using near-infrared spectroscopy. Step counts and physical activity (average vector magnitude units [VMU] per minute) were measured over 5-7 d using triaxial accelerometry. Untargeted prime and lipid metabolites were measured using liquid chromatography and mass spectrometry.

RESULTS

Muscle k (1.12 ± 0.05 vs 1.68 ± 0.06 min, P < 0.0001, d = 1.58) and VMU per minute (170 ± 26 vs 450 ± 50 VMU per minute, P = 0.004, d = 1.04) were lower in severe COPD (FEV1 < 50% predicted, n = 14-16) compared with CON (n = 56-60). A total of 129 prime metabolites and 470 lipids with known identity were quantified. Using sex as a covariate, lipidomics revealed 24 differentially expressed lipids (19 sphingomyelins) in COPD, consequent to a diminished sex difference of sphingomyelins in COPD (false discovery rate [FDR] < 0.05, n = 44). Total, and some individual, fatty acid concentrations were greater in severe COPD than CON (FDR < 0.05, n = 16, d = 0.56-1.02). After adjusting for FEV1% predicted, we observed that grouped diacylglycerides (ρ = -0.745, FDR = 0.03) and triacylglycerides (ρ = -0.811, FDR = 0.01) were negatively associated with muscle oxidative capacity, but not physical activity, in severe COPD (n = 14).

CONCLUSION

Strong negative associations relate impaired mitochondrial function to the accumulation of serum aclyglycerides in severe COPD.

Telementoring of Healthcare Teams in the Care of Miners

Background: Given the reemergence of pneumoconiosis in the United States, there is a tremendous need to train rural professionals in its multidisciplinary management. The Miners' Wellness TeleECHO (Telementoring Extension for Community Health Outcomes) Program in New Mexico, United States, provides longitudinal multidisciplinary telementoring to professionals taking care of miners. The impact of this approach has not been previously evaluated.

Objective: To examine the change in self-efficacy of professionals taking care of miners and participating in the TeleECHO Program.

Methods: This is a 12-month longitudinal study involving clinical and nonclinical professionals caring for miners. The study outcome was the change in self-efficacy scores, using a customized instrument of 14 measures grouped into three domains: clinical, medicolegal, and soft skills. The primary outcome used a retrospective pre-post design that collects "pretest" data at the postintervention timeframe.

Results: Participants reported significant improvements in 10 of 14 items (P < 0.05) and a significant decline in 1 of 14 items (with respect to their ability to interpret pulmonary function test results, P < 0.001) since their start dates in the program. Subjects also reported significant improvement with respect to their scores for all three domains and for the 14-item total score (P ⩽ 0.01). Existing participants and clinical professional groups demonstrated greater improvement in selected items than fresh participants and nonclinical professional groups, respectively.

Conclusion: This study is the first in a stepwise approach to determine the benefit of participating in a multidisciplinary telementoring intervention by improving participant self-efficacy in caring for miners with complex mining-related diseases. Our study finding represents a potential solution to a growing access-to-care gap for miners with pneumoconiosis.

Real-Life Clinical and Functional Effects of Fluticasone Furoate/Umeclidinium/Vilanterol-Combined Triple Therapy in Patients with Chronic Obstructive Pulmonary Disease

BACKGROUND

Triple therapy consisting of a drug association including an inhaled corticosteroid, a long-acting muscarinic receptor antagonist and a long-acting β2-adrenergic agonist, delivered via a single device, can be a valuable treatment for chronic obstructive pulmonary disease (COPD) patients experiencing frequent disease exacerbations.

OBJECTIVES

The aim of this real-life, single-center, observational study was to evaluate, in 44 COPD patients with recurrent exacerbations, the effects of the triple inhaled therapy combining fluticasone furoate, umeclidinium, and vilanterol (FF/UMEC/VI).

METHODS

Within such a therapeutic context, several clinical and lung functional parameters were considered at baseline and after 24 weeks of treatment with combined inhaled triple therapy.

RESULTS

With respect to baseline, after 24 weeks of treatment with FF/UMEC/VI, significant changes were recorded with regard to Modified British Medical Research Council (p < 0.0001) and COPD Assessment Test (p < 0.0001) scores, COPD exacerbations (p < 0.001), forced expiratory volume in the first second (p < 0.001), residual volume (p < 0.01), forced mid-expiratory flow between 25 and 75% of FVC (p < 0.0001), inspiratory capacity (p < 0.01), forced vital capacity (p < 0.05), and peak expiratory flow (p < 0.0001). Moreover, in a subgroup of 28 patients, a significant increase of diffusion lung capacity (p < 0.01) was also detected.

CONCLUSIONS

In conclusion, our real-life results suggest that triple inhaled therapy with FF/UMEC/VI, when given to COPD patients with frequent exacerbations, is able to positively impact on dyspnea and global health status as well as to significantly decrease COPD exacerbations and improve airflow limitation and lung hyperinflation.

Clinical Molecular Imaging of Pulmonary CXCR4 Expression to Predict Outcome of Pirfenidone Treatment in Idiopathic Pulmonary Fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a progressive disease for which two antifibrotic drugs recently were approved. However, an unmet need exists to predict responses to antifibrotic treatment, such as pirfenidone. Recent data suggest that upregulated expression of CXCR4 is indicative of outcomes in IPF.

RESEARCH QUESTION

Can quantitative, molecular imaging of pulmonary CXCR4 expression as a biomarker for disease activity predict response to the targeted treatment pirfenidone and prognosis in patients with IPF?

STUDY DESIGN AND METHODS

CXCR4 expression was analyzed by immunohistochemistry examination of lung tissues and reverse-transcriptase polymerase chain reaction analysis of BAL. PET-CT scanning with the specific CXCR4 ligand ⁶⁸Ga-pentixafor was performed in 28 IPF patients and compared with baseline clinical characteristics. In 16 patients, a follow-up scan was obtained 6 to 12 weeks after initiation of treatment with pirfenidone. Patients were followed up in our outpatient clinic for ≥ 12 months.

RESULTS

Immunohistochemistry analysis showed high CXCR4 staining of epithelial cells and macrophages in areas with vast fibrotic remodeling. Targeted PET scanning revealed CXCR4 upregulation in fibrotic areas of the lungs, particularly in zones with subpleural honeycombing. Baseline CXCR4 signal demonstrated a significant correlation with Gender Age Physiology stage (r = 0.44; P = .02) and with high-resolution CT scan score (r = 0.38; P = .04). Early changes in CXCR4 signal after initiation of pirfenidone treatment correlated with the long-term course of FVC after 12 months (r = -0.75; P = .0008). Moreover, patients with a high pulmonary CXCR4 signal on follow-up PET scan after 6 weeks into treatment demonstrated a statistically significant worse outcome at 12 months (P = .002). In multiple regression analysis, pulmonary CXCR4 signal on follow-up PET scan emerged as the only independent predictor of long-term outcome (P = .0226).

INTERPRETATION

CXCR4-targeted PET imaging identified disease activity and predicted outcome of IPF patients treated with pirfenidone. It may serve as a future biomarker for personalized guidance of antifibrotic treatment.

Inspiratory Muscle Training Potentiates the Beneficial Effects of Proportional Assisted Ventilation on Exertional Dyspnea and Exercise Tolerance in COPD: A Proof-of-Concept Randomized and Controlled Trial

During pulmonary rehabilitation, a subset of subjects with COPD requires adjunct therapy to achieve high-intensity training. Both noninvasive ventilation (NIV) and inspiratory muscle training (IMT) are available to assist these subjects. We aimed to prime the respiratory muscles before NIV with IMT, anticipating additive effects for maximal exercise tolerance (T _lim) and dyspnea/leg fatigue relief throughout the exercise as primary outcomes. Changes in the respiratory pattern were secondary outcomes. COPD subjects performed a total of four identical constant work rate tests on a cycle ergometer at 75% of maximum work rate, under control ventilation (SHAM, 4 cm H₂O) or proportional assisted ventilation (PAV, individually adjusted), before and after 10 sessions of high-intensity IMT (three times/week) during 30 days. Two-way RM ANOVA with appropriate corrections were performed. Final analysis in nine subjects showed improved T _lim (Δ = 111 s) and lower minute-ventilation (Δ = 4 L^.min^-1) at exhaustion, when comparing the IMT effects within the PAV modality (p = 0.001 and p = 0.036, respectively) and improved T _lim for PAV vs. SHAM (PAV main-effect, p = 0.001; IMT main-effect, p = 0.006; PAV vs. IMT interaction, p = 0.034). In addition, IMT + PAV association, compared to PAV alone, resulted in lower respiratory frequency (IMT main-effect, p = 0.009; time main-effect, p < 0.0001; IMT vs. time interaction, p = 0.242) and lower inspiratory time related to duty cycle (IMT main-effect, p = 0.018; time main-effect, p = 0.0001; IMT vs. time interaction, p = 0.004) throughout exercise. The addition of IMT prior to a PAV-supported aerobic bout potentiates exercise tolerance and dyspnea relief and induces favourable changes in ventilatory pattern in severe COPD during high-intensity training (Brazilian Registry of Clinical Trials, number RBR-6n3dzz).

Impaired lung function following e-cigarette or vaping product use associated lung injury in the first cohort of hospitalized adolescents

BACKGROUND

Beginning June 2019, Children's Wisconsin was the first hospital to identify a cohort of adolescent patients hospitalized with symptoms likely associated with e-cigarette use. Our report adds to the growing literature describing the radiographic, gross and cytopathologic bronchoscopic findings, and short-term lung function outcomes in this cohort of adolescents with e-cigarette or vaping product use associated lung injury (EVALI).

METHODS

We present 15 adolescents hospitalized from June to September, 2019 with confirmed EVALI. We abstracted data from inpatient hospitalization and first outpatient pulmonary clinic visit.

RESULTS

There were 15 patients (11 male, 12 White) with a mean age of 17.1 years. All patients presented with subacute pulmonary, gastrointestinal and constitutional complaints. Diagnostic workup was guided by the Centers for Disease Control criteria for confirmed EVALI case surveillance. Flexible bronchoscopy was performed in 13/15 patients with 10/13 demonstrating gross pathologic abnormalities. Seven of 15 patients required intensive care and 2 met criteria for pediatric Acute Respiratory Distress Syndrome. Patients had dramatic improvement with systemic glucocorticoid therapy and 14/15 were discharged on room air. Eleven patients were seen as outpatients. Despite 11/11 patients reporting resolved or improved symptoms, 7/11 had abnormalities on pulmonary function testing. We initiated inhaled corticosteroids for 5/11 patients and 4/11 patients remained on their corticosteroid wean.

CONCLUSIONS AND RELEVANCE

We report short-term outcomes of the first cohort of adolescent patients hospitalized with EVALI. An association is observed between clinical improvement and treatment with systemic corticosteroids. However, residual airway reactivity or diffusion abnormalities persisted when patients were re-evaluated in the short-term period (mean 4.5 weeks).

A Comprehensive Evaluation of Mepolizumab Effectiveness in a Real-Life Setting

INTRODUCTION

Interleukin-5 (IL-5) is the principal cytokine regulating eosinophil growth, differentiation, activation, and expression. It is a specific target of mepolizumab, an anti-IL-5 monoclonal antibody used in the treatment of severe eosinophilic asthma. This new drug can improve symptoms, reduce asthma exacerbations and steroid use. Few data are available on its efficacy for nasal symptoms.

OBJECTIVE

To describe the all-round clinical impact of mepolizumab in a real-life setting, evaluating the efficacy and safety of the drug in severe eosinophilic asthma patients.

POPULATION AND METHODS

We retrospectively collected the clinical and functional data on 27 patients (16 males) affected with severe eosinophilic asthma, diagnosed at the Siena Regional Referral Centre and monitored for 6 months. Clinical, immunological, and functional data at baseline and follow-up were entered in a database together with comorbidities, number of exacerbations, steroid treatment, multiple-flow exhaled nitric oxide, and validated questionnaires.

RESULTS

A significant reduction in asthma exacerbations was observed in all patients after 6 months of the biological therapy (p = 0.0009), and 4/6 patients discontinued chronic oral steroids. A significant improvement in ACT, FEV1, SNOT22, and alveolar nitric oxide was observed after 1 month of mepolizumab (p = 0.003, p = 0.007, p = 0.047, and p = 0.019, respectively) and maintained after 6 months of treatment. After 6 months, FeNO 50 was reduced as well (p = 0.030). Mepolizumab was very well tolerated, and no major side effects were observed.

CONCLUSIONS

Our study suggests that mepolizumab is effective in improving control of asthma, lung function parameters, exhaled biomarkers, and nasal symptoms in patients with severe eosinophilic asthma.

Lung Diffusing Capacities (DL ) for Nitric Oxide (NO) and Carbon Monoxide (CO): The Evolving Story

Nitric oxide and carbon monoxide diffusing capacities (D_LNO and D_LCO ) obey Fick's First Law of Diffusion and the basic principles of chemical kinetic theory. NO gas transfer is dominated by membrane diffusion (D_M ), whereas CO transfer is limited by diffusion plus chemical reaction within the red cell. Marie Krogh, who pioneered the single-breath measurement of D_LCO in 1915, believed that the combination of CO with red cell hemoglobin (Hb) was instantaneous. Roughton and colleagues subsequently showed, in vitro, that the reaction rate was finite, and prolonged in the presence of high P O 2 . Roughton and Forster (R-F) proposed that the resistance to transfer (1/D_L ) was the sum of the membrane resistance (1/D_M ) and (1/θVc), the red cell resistance (θ being the CO or NO conductance for blood uptake and Vc the capillary volume). From this R-F equation, D_M for CO and Vc can be solved with simultaneous NO and CO inhalation. At near maximum exercise, D_MCO and Vc for normal subjects were 88% and 79%, respectively, of morphometric values. The validity of these calculations depends on the values chosen for θ for CO and NO, and on the diffusivity of NO versus CO. Recent mathematical modeling suggests that θ for NO is "effectively" infinite because NO reacts only with Hb in the outer 0.1 μM of the red cell. An "infinite θ_NO " recalculation reduced D_MCO to 53% and increased Vc to 95% of morphometric values. © 2020 American Physiological Society. Compr Physiol 10:73-97, 2020.

Health status deterioration in subjects with mild to moderate airflow obstruction, a six years observational study

Background

Patients with COPD need to cope with a disabling disease, which leads to health status impairment.

Aim

To investigate the long term change of health status in subjects with mild to moderate airflow obstruction and to compare this to subjects without airflow obstruction, with and without a smoking history. Second, to investigate the factors potentially associated to rapid health status decline in our total cohort.

Methods

Two hundred and one subjects were included. Generic [Short form 36 health survey (SF36) and EuroQol - 5 dimensions (EQ-5D)] and disease specific [Clinical COPD questionnaire (CCQ) and COPD Assessment Test (CAT)] health status questionnaires were regularly repeated over a six years period. Other functional outcomes comprised measures of lung function, physical fitness, physical activity and emotional state.

Results

On average, health status decline did not differ between groups with the exception of the EQ-5D index, which deteriorated faster in subjects with airflow obstruction compared to the never smoking control group [− 0.018(0.008) versus 0.00006(0.003), p = 0.03]. Subjects presenting at least one exacerbation had faster rate of deterioration measured with CAT [0.91(0.21) versus − 0.26(0.25), p < 0.01]. Characteristics of the fast declining group were older age, worse lung function, physical fitness, physical activity and disease specific baseline health status. Subjects with airflow obstruction had a 2.5 (95% CI 1.36–4.71) higher risk of presenting fast overall health status decline. Fast overall decline was associated with the presence of acute exacerbation(s) (44% of the subjects with exacerbation(s) versus 17% of subjects without exacerbation, p = 0.03). Changes in fat free mass, functional exercise capacity and in symptoms of anxiety and depression correlated weakly to changes in health status measured with all questionnaires.

Conclusion

Subjects with mild airflow obstruction present a significant deterioration of health status, which is generally not much faster compared to smoking and never smoking controls. Subjects with fast decline in overall health status are older and more likely to have airflow obstruction, acute respiratory exacerbation(s), reduced physical fitness, physical activity and impaired COPD specific health status at baseline.

Trial registration

NCT01314807 - retrospectively registered on March 2011.

Electronic supplementary material

The online version of this article (10.1186/s12931-019-1061-7) contains supplementary material, which is available to authorized users.

Progression of Left Ventricular Myocardial Dysfunction in Systemic Sclerosis: A Speckle-tracking Strain Echocardiography Study

OBJECTIVE

Cardiac involvement is a main cause of mortality in systemic sclerosis (SSc). Its detection remains challenging using conventional echocardiography and little is known about its potential progression. This study assessed changes in cardiac performance over time in a prospective cohort of patients with SSc, including echocardiographic speckle-tracking strain analysis.

METHODS

The study included 234 patients with SSc [196 women, age 52 ± 14 yrs, 165 limited SSc, time since diagnosis 5.2 yrs, interquartile range (IQR) 2.9-11.3]. Clinical variables, laboratory tests, pulmonary function tests, and echocardiographic measures were recorded at baseline and followup (median 2.3 yrs, IQR 1.3-3.9). Additionally, left ventricular (LV) systolic function was assessed with global longitudinal strain (GLS) by echocardiographic speckle-tracking analysis.

RESULTS

At followup, GLS had significantly worsened (-21% ± 2 vs -19% ± 2, p < 0.001) while LV ejection fraction had not changed (62% ± 7 vs 61% ± 8, p = 0.124). In particular, 39 patients showed a significant deterioration of GLS as defined by a ≥ 15% decrease, which was accompanied by a concomitant worsening of proximal muscle weakness, lung fibrosis, renal function, LV diastolic function, and right ventricular systolic function. Baseline variables associated with ≥ 15% deterioration in GLS were proximal muscle weakness (OR 3.437, 95% CI 1.13-10.43, p = 0.020), decreased DLCO (OR 3.621, 95% CI 1.25-10.51, p = 0.049), and LV diastolic dysfunction (OR 2.378, 95% CI 1.07-5.27, p = 0.033).

CONCLUSION

In patients with SSc, progression of LV systolic dysfunction was demonstrated by GLS but not by LV ejection fraction. Proximal muscle weakness, DLCO, and LV diastolic dysfunction may identify patients at risk for progressive LV systolic dysfunction and in need of closer cardiac monitoring.

Turkish Thoracic Society Consensus Report: Interpretation of Spirometry

ÖZET: Günümüzde spirometre ölçümlerinin uygulama ve yorumlama nitelik güvencesi "American Thoracic Society / European Respiratory Society" standartları ile belirlenmiştir. Dünyada olduğu gibi ülkemizde de birçok laboratuvar bu standartları kullanmaktadır. Buna karşın, farklı laboratuvarlardan farklı değerlendirme sonuçları görebilmek mümkündür. Bu rapor, ülkemizdeki solunum fonksiyon testi laboratuvarlarında yapılan değerlendirmelerin standardizasyonunu sağlamak amacı ile hazırlanmıştır.

Six years progression of exercise capacity in subjects with mild to moderate airflow obstruction, smoking and never smoking controls

BACKGROUND

Exercise capacity is an important feature in patients with COPD. Its impairment drives disability and dependency for daily activities performance. This study evaluated the six years change in exercise capacity in subjects with airflow obstruction and compared this to subjects without airflow obstruction, with and without a smoking history.

METHODS

Cardiopulmonary exercise tests (CPET) were repeatedly performed during a six years follow up period. Peak oxygen uptake (VO2peak), work rate (WRpeak), heart rate (HRpeak), minute ventilation (VEpeak), respiratory exchange ratio (RERpeak) and ventilatory reserve (VE/MVV) were collected as effort dependent outcomes. The slopes of oxygen uptake, ventilatory and mechanical efficiency (OUES, ΔVE/ΔVCO2 and ΔVO2/ΔWR) were collected as effort independent outcomes.

RESULTS

One hundred and thirty-eight subjects were included. Thirty-eight presented airflow obstruction (63±6 years, 74% men, FEV1 90±15%pred), 44 had a smoking history but no airflow obstruction (61±5 years, 61% men, FEV1 105±15%pred) and 56 had never smoked (61±7 years, 57% men, FEV1 117±18%pred). At baseline, the airflow obstruction group had slightly worse exercise capacity in comparison to the never smoking control group, in absolute terms and expressed as percentage of the predicted value (VO2peak = 27±5 versus 32±8 ml/min/kg, p<0.01; 112±29 versus 130±33%pred, p = 0.04). Most exercise variables showed a statistically significant yearly deterioration, with exception of VE/MVV, ΔVE/ΔVCO2 and ΔVO2/ΔWR. The yearly decline in VO2peak and OUES was not faster in subjects with airflow obstruction than in smoking and never smoking controls (VO2peak -67 (9) versus -76 (9) ml/min, p = 0.44 and versus -58 (9), p = 0.47; OUES -32 (11) versus -68 (10), p = 0.03 and versus -68 (13), p = 0.03).

CONCLUSIONS

With exception of VO2peak, effort dependent variables deteriorated faster in subjects with airflow obstruction compared to never smoking controls. The deterioration of effort independent variables, however, was not accelerated in the airflow obstruction group compared to controls.

Survival in pulmonary hypertension due to chronic lung disease: Influence of low diffusion capacity of the lungs for carbon monoxide

BACKGROUND

Patients with pulmonary hypertension (PH) due to chronic lung disease (Group 3 PH) have poor long-term outcomes. However, predictors of survival in Group 3 PH are not well described.

METHODS

We performed a cohort study of Group 3 PH patients (n = 143; mean age 65 ± 12 years, 52% female) evaluated at the University of Minnesota. The Kaplan-Meier method and Cox regression analysis were used to assess survival and predictors of mortality, respectively. The clinical characteristics and survival were compared in patients categorized by PH severity based on the World Health Organization (WHO) classification and lung disease etiology.

RESULTS

After a median follow-up of 1.4 years, there were 69 (48%) deaths. The 1-, 3-, and 5-year survival rates were 79%, 48%, and 31%. Age, coronary artery disease, atrial fibrillation, Charlson comorbidity index, serum N-terminal pro‒brain natriuretic peptide (NT-proBNP), creatinine, diffusion capacity of carbon monoxide (DLCO), total lung capacity, left ventricular ejection fraction, right atrial and right ventricular enlargement on echocardiography, cardiac index, and pulmonary vascular resistance (PVR) were univariate predictors of survival. On multivariable analysis, DLCO was the only predictor of mortality (adjusted hazard ratio [HR] for every 10% decrease in predicted value: 1.31 [95% confidence interval 1.12 to 1.47]; p = 0.003). The 1-/5-year survival by tertiles of DLCO was 84%/56%, 82%/44%, and 63%/14% (p = 0.01), respectively. On receiver-operating characteristic curve analysis, DLCO <32% of predicted had the highest sensitivity and specificity for predicting survival. The 1- and 5-year survival in patients with a DLCO ≥32% predicted was 84% and 60% vs 68% and 13% in patients with a DLCO <32% predicted (adjusted HR: 2.5 [95% confidence interval 1.3 to 5.0]; p = 0.007). Lung volumes and DLCO were not related, but higher PVR was strongly associated with reduced DLCO. There was increased mortality in interstitial lung disease‒PH as compared with chronic obstructive pulmonary disease‒PH, but PH severity based on the WHO classification did not alter survival.

CONCLUSIONS

Low DLCO is a predictor of mortality and should be used to risk-stratify Group 3 PH patients.

Combined diffusing capacity for nitric oxide and carbon monoxide as predictor of bronchiolitis obliterans syndrome following lung transplantation

BACKGROUND

There is a need for non-invasive parameters that are sensitive to the development of the bronchiolitis obliterans syndrome (BOS) in lung transplantation (LTx) patients. We studied whether the pulmonary diffusing capacity for inhaled nitric oxide is capable of detecting BOS stages.

METHODS

Sixty-one LTx patients were included into this cross-sectional study (19/29/7/3/3 in BOS stages 0/0-p/1/2/3). For analysis stages 0/0-p versus 1/2/3 ("BOS binary-early"), and stages 0/0-p/1 versus 2/3 ("BOS binary-late") were summarized. Measurements of the combined diffusing capacity for nitric oxide (DLNO) and carbon monoxide (DLCO) were compared with spirometry and bodyplethysmography, and their relative importance was evaluated by discriminant analysis.

RESULTS

Regarding the recognition of "BOS binary-early", among spirometric parameters forced expiratory volume in 1 s (FEV1) was best, among bodyplethysmographic parameters airway resistance, and among diffusing parameters DLNO. Regarding "BOS binary-late", DLNO was inferior to bodyplethysmographic parameters.

CONCLUSION

Although the study comprised only measurements at a single time point and no follow-up, DLNO outperformed FEV1, the time course of which is used in detecting BOS. Together with its pathophysiological plausibility, this result suggests that the measurement of DLNO, possibly over time, could be an easily applicable tool for the monitoring of LTx patients and should be evaluated in larger studies.

Exhaled Nitric Oxide and Exhaled Breath Temperature as Potential Biomarkers in Patients with Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension (PH) is a progressive fatal disease thus, noninvasive prognostic tools are needed to follow these patients. The aim of our study was to evaluate fractional exhaled nitric oxide (FeNO) and exhaled breath temperature (EBT) values in patients with PH from different causes and to correlate them with respiratory functional data.

METHODS

Twenty-four PH patients underwent spirometry, carbon monoxide diffusion (DLCO) test, transthoracic echocardiography, right-heart catheterization, and FeNO and EBT measurements.

RESULTS

We studied 3 groups according to the type of PH: 10 patients with pulmonary arterial hypertension (PAH) (group A), 11 patients with PH due to chronic obstructive pulmonary disease (COPD) (group B), and 3 patients with PH associated with left heart disease (group C). Mean FeNO values tend to be higher in group B (15.0 ± 9.3ppb) compared with other groups (respectively, 9.9 ± 5.7 and 8.5 ± 5.2 ppb in groups A and C; p = 0.271) but no statistical significance has been reached. Mean values of alveolar NO concentration (CANO) were higher in groups A and B compared to group C (respectively, 16.9 ± 12.6; 13.9 ± 6.8; and 6.7 ± 2.0 ppb) (p = 0.045). EBT mean values were significantly lower in group C when compared with other groups (group C: 29.0 +- 1.3°C, groups A and B: 30.9 ± 1.3 and 31.2 ± 1.2°C, respectively: p = 0.041). EBT levels were inversely correlated to mean pulmonary artery pressure (PAPm) levels (Spearman coefficient -0.481; p = 0.017).

CONCLUSIONS

eNO, CANO, and EBT have been evaluated in three groups of PH patients. Interestingly EBT reduction was correlated with PAPm increase, whereas FeNO was higher in COPD patients and CANO in PAH and COPD groups. Further studies are needed to clarify EBT, FeNO, and CANO roles as biomarkers in the monitoring of patients with PH.

Shrinking lung syndrome in systemic lupus erythematosus: a single-centre experience

Introduction Shrinking lung syndrome (SLS) is a rare manifestation of systemic lupus erythematosus (SLE), characterized by decreased lung volumes and extra-pulmonary restriction. The aim of this study was to describe the characteristics of SLS in our lupus cohort with emphasis on prevalence, presentation, treatment and outcomes. Patients and methods Patients attending the Toronto Lupus Clinic since 1980 ( n = 1439) and who had pulmonary function tests (PFTs) performed during follow-up were enrolled ( n = 278). PFT records were reviewed to characterize the pattern of pulmonary disease. SLS definition was based on a restrictive ventilatory defect with normal or slightly reduced corrected diffusing lung capacity for carbon monoxide (DLCO) in the presence of suggestive clinical (dyspnea, chest pain) and radiological (elevated diaphragm) manifestations. Data on clinical symptoms, functional abnormalities, imaging, treatment and outcomes were extracted in a dedicated data retrieval form. Results Twenty-two patients (20 females) were identified with SLS for a prevalence of 1.53%. Their mean age was 29.5 ± 13.3 years at SLE and 35.7 ± 14.6 years at SLS diagnosis. Main clinical manifestations included dyspnea (21/22, 95.5%) and pleuritic chest pain (20/22, 90.9%). PFTs were available in 20 patients; 16 (80%) had decreased maximal inspiratory (MIP) and/or expiratory pressure (MEP). Elevated hemidiaphragm was demonstrated in 12 patients (60%). Treatment with prednisone and/or immunosuppressives led to clinical improvement in 19/20 cases (95%), while spirometrical improvement was observed in 14/16 patients and was mostly partial. Conclusions SLS prevalence in SLE was 1.53%. Treatment with glucocorticosteroids and immunosuppressives was generally effective. However, a chronic restrictive ventilatory defect usually persisted.

2017 ERS/ATS standards for single-breath carbon monoxide uptake in the lung

This document provides an update to the European Respiratory Society (ERS)/American Thoracic Society (ATS) technical standards for single-breath carbon monoxide uptake in the lung that was last updated in 2005. Although both D_LCO (diffusing capacity) and T_LCO (transfer factor) are valid terms to describe the uptake of carbon monoxide in the lung, the term D_LCO is used in this document. A joint taskforce appointed by the ERS and ATS reviewed the recent literature on the measurement of D_LCO and surveyed the current technical capabilities of instrumentation being manufactured around the world. The recommendations in this document represent the consensus of the taskforce members in regard to the evidence available for various aspects of D_LCO measurement. Furthermore, it reflects the expert opinion of the taskforce members on areas in which peer-reviewed evidence was either not available or was incomplete. The major changes in these technical standards relate to D_LCO measurement with systems using rapidly responding gas analysers for carbon monoxide and the tracer gas, which are now the most common type of D_LCO instrumentation being manufactured. Technical improvements and the increased capability afforded by these new systems permit enhanced measurement of D_LCO and the opportunity to include other optional measures of lung function.