Machine learning for accurate detection of small airway dysfunction-related respiratory changes: an observational study.

BACKGROUND: The use of machine learning(ML) methods would improve the diagnosis of small airway dysfunction(SAD) in subjects with chronic respiratory symptoms and preserved pulmonary function(PPF). This paper evaluated the performance of several ML algorithms associated with the impulse oscillometry(IOS) analysis to aid in the diagnostic of respiratory changes in SAD. We also find out the best configuration for this task. METHODS: IOS and spirometry were measured in 280 subjects, including a healthy control group (n = 78), a group with normal spirometry (n = 158) and a group with abnormal spirometry (n = 44). Various supervised machine learning (ML) algorithms and feature selection strategies were examined, such as Support Vector Machines (SVM), Random Forests (RF), Adaptive Boosting (ADABOOST), Navie Bayesian (BAYES), and K-Nearest Neighbors (KNN). RESULTS: The first experiment of this study demonstrated that the best oscillometric parameter (BOP) was R5, with an AUC value of 0.642, when comparing a healthy control group(CG) with patients in the group without lung volume-defined SAD(PPFN). The AUC value of BOP in the control group was 0.769 compared with patients with spirometry defined SAD(PPFA) in the PPF population. In the second experiment, the ML technique was used. In CGvsPPFN, RF and ADABOOST had the best diagnostic results (AUC = 0.914, 0.915), with significantly higher accuracy compared to BOP (p < 0.01). In CGvsPPFA, RF and ADABOOST had the best diagnostic results (AUC = 0.951, 0.971) and significantly higher diagnostic accuracy (p < 0.01). In the third, fourth and fifth experiments, different feature selection techniques allowed us to find the best IOS parameters (R5, (R5-R20)/R5 and Fres). The results demonstrate that the performance of ADABOOST remained essentially unaltered following the application of the feature selector, whereas the diagnostic accuracy of the remaining four classifiers (RF, SVM, BAYES, and KNN) is marginally enhanced. CONCLUSIONS: IOS combined with ML algorithms provide a new method for diagnosing SAD in subjects with chronic respiratory symptoms and PPF. The present study's findings provide evidence that this combination may help in the early diagnosis of respiratory changes in these patients.

Impulse oscillometry for detection of small airway dysfunction in subjects with chronic respiratory symptoms and preserved pulmonary function.

BACKGROUND: Subjects with chronic respiratory symptoms and preserved pulmonary function (PPF) may have small airway dysfunction (SAD). As the most common means to detect SAD, spirometry needs good cooperation and its reliability is controversial. Impulse oscillometry (IOS) may complete the deficiency of spirometry and have higher sensitivity. We aimed to explore the diagnostic value of IOS to detect SAD in symptomatic subjects with PPF. METHODS: The evaluation of symptoms, spirometry and IOS results in 209 subjects with chronic respiratory symptoms and PPF were assessed. ROC curves of IOS to detect SAD were analyzed. RESULTS: 209 subjects with chronic respiratory symptoms and PPF were included. Subjects who reported sputum had higher R5-R20 and Fres than those who didn't. Subjects with dyspnea had higher R5, R5-R20 and AX than those without. CAT and mMRC scores correlated better with IOS parameters than with spirometry. R5, R5-R20, AX and Fres in subjects with SAD (n = 42) significantly increased compared to those without. Cutoff values for IOS parameters to detect SAD were 0.30 kPa/L s for R5, 0.015 kPa/L s for R5-R20, 0.30 kPa/L for AX and 11.23 Hz for Fres. Fres has the largest AUC (0.665, P = 0.001) among these parameters. Compared with spirometry, prevalence of SAD was higher when measured with IOS. R5 could detect the most SAD subjects with a prevalence of 60.77% and a sensitivity of 81% (AUC = 0.659, P = 0.002). CONCLUSION: IOS is more sensitive to detect SAD than spirometry in subjects with chronic respiratory symptoms and PPF, and it correlates better with symptoms. IOS could be an additional method for SAD detection in the early stage of diseases.

Small Airway Dysfunction in Asthma Is Associated with Perceived Respiratory Symptoms, Non-Type 2 Airway Inflammation, and Poor Responses to Therapy.

BACKGROUND: Emerging evidence has indicated that small airway dysfunction (SAD) contributes to the clinical expression of asthma. OBJECTIVES: The aim of the study was to explore the relationships of SAD assessed by forced expiratory flow between 25 and 75% (FEF25-75%), with clinical and inflammatory profile and treatment responsiveness in asthma. METHOD: In study I, dyspnea intensity (Borg scale), chest tightness, wheezing and cough (visual analog scales, VASs), and pre- and post-methacholine challenge testing (MCT) were analyzed in asthma patients with SAD and non-SAD. In study II, asthma subjects with SAD and non-SAD underwent sputum induction, and inflammatory mediators in sputum were detected. Asthma patients with SAD and non-SAD receiving fixed treatments were prospectively followed up for 4 weeks in study III. Spirometry, Asthma Control Questionnaire (ACQ), and Asthma Control Test (ACT) were carried out to define treatment responsiveness. RESULTS: SAD subjects had more elevated ΔVAS for dyspnea (p = 0.027) and chest tightness (p = 0.032) after MCT. Asthma patients with SAD had significantly elevated interferon (IFN)-γ in sputum (p < 0.05), and Spearman partial correlation found FEF25-75% significantly related to IFN-γ and interleukin-8 (both having p < 0.05). Furthermore, multivariable regression analysis indicated SAD was significantly associated with worse treatment responses (decrease in ACQ ≥0.5 and increase in ACT ≥3) (p = 0.022 and p = 0.032). CONCLUSIONS: This study indicates that SAD in asthma predisposes patients to greater dyspnea intensity and chest tightness during bronchoconstriction. SAD patients with asthma are characterized by non-type 2 inflammation that may account for poor responsiveness to therapy.

Correction to: The effect of corticosteroids on the mortality of patients with influenza pneumonia: a systematic review and meta-analysis.

An amendment to this paper has been published and can be accessed via the original article.

The effect of corticosteroids on mortality of patients with influenza pneumonia: a systematic review and meta-analysis.

BACKGROUND: The effect of corticosteroids on clinical outcomes in patients with influenza pneumonia remains controversial. We aimed to further evaluate the influence of corticosteroids on mortality in adult patients with influenza pneumonia by comparing corticosteroid-treated and placebo-treated patients. METHODS: The PubMed, Embase, Medline, Cochrane Central Register of Controlled Trials (CENTRAL), and Information Sciences Institute (ISI) Web of Science databases were searched for all controlled studies that compared the effects of corticosteroids and placebo in adult patients with influenza pneumonia. The primary outcome was mortality, and the secondary outcomes were mechanical ventilation (MV) days, length of stay in the intensive care unit (ICU LOS), and the rate of secondary infection. RESULTS: Ten trials involving 6548 patients were pooled in our final analysis. Significant heterogeneity was found in all outcome measures except for ICU LOS (I2 = 38%, P = 0.21). Compared with placebo, corticosteroids were associated with higher mortality (risk ratio [RR] 1.75, 95% confidence interval [CI] 1.30 ~ 2.36, Z = 3.71, P = 0.0002), longer ICU LOS (mean difference [MD] 2.14, 95% CI 1.17 ~ 3.10, Z = 4.35, P < 0.0001), and a higher rate of secondary infection (RR 1.98, 95% CI 1.04 ~ 3.78, Z = 2.08, P = 0.04) but not MV days (MD 0.81, 95% CI - 1.23 ~ 2.84, Z = 0.78, P = 0.44) in patients with influenza pneumonia. CONCLUSIONS: In patients with influenza pneumonia, corticosteroid use is associated with higher mortality. TRIAL REGISTRATION: PROSPERO (ID: CRD42018112384 ).

Rapid versus gradual lung function decline in bronchiolitis obliterans syndrome after haematopoietic stem cell transplantation is associated with survival outcome.

BACKGROUND AND OBJECTIVE: Bronchiolitis obliterans syndrome (BOS) after haematopoietic stem cell transplantation (HSCT) presents with lung function decline. The pattern of lung function decline after BOS diagnosis could impact prognostication of BOS as a complication after HSCT. The aim of this study was to assess the impact of lung function decline on overall survival (OS) in BOS subjects. METHODS: Subjects with BOS were compared to those without BOS and matched for age, gender, primary diagnoses, conditioning regimes and chronic graft versus host disease. Lung function tests at baseline, at BOS diagnosis and every 3 months after HSCT were evaluated. RESULTS: Of the 1461 subjects undergoing allogeneic HSCT (allo-HSCT) between 1998 and 2015, 95 (6.5%) were diagnosed with BOS. A total of 159 matched HSCT recipients without BOS were identified. A 25% decline in FEV1 within the first 3 months after BOS diagnosis would separate BOS subjects into a subgroup with initial rapid decline and another subgroup with initial gradual decline in lung function. The rapid decline group showed lower subsequent lung function parameters and significantly worse OS compared to the gradual decline group (P = 0.013). CONCLUSION: Post-HSCT BOS subjects with initial rapid lung function decline within 3 months after BOS diagnosis will have significantly poorer lung function and worse OS compared to those with initial gradual decline in lung function after BOS diagnosis. HSCT BOS patients with rapid initial decline in lung function warrant closer monitoring for the development of other post-HSCT complications that could affect their survival.

Can corticosteroids reduce the mortality of patients with severe sepsis? A systematic review and meta-analysis.

BACKGROUND: The effects of corticosteroids on clinical outcomes of patients with sepsis remains controversial. We aimed to further determine the effectiveness of corticosteroids in reducing mortality in adult patients with severe sepsis by comparison with placebo. METHODS: Pubmed, Embase, Medline, Cochrane Central Register of Controlled Trials (CENTRAL) as well as the Information Sciences Institute (ISI) Web of Science were searched for all controlled studies that compared corticosteroids and placebo in adult patients with severe sepsis. The primary outcome was the mortality 28-day mortality and the secondary outcomes were mortality at longest follow up, occurrence, and reoccurrence of septic shock. RESULTS: A total of 19 trials involving 7035 patients were pooled in our final analyses. No significant heterogeneity was found in any of the outcome measures. Compared with placebo, corticosteroids were associated with a lower 28-day mortality (RR 0.91, 95% CI 0.85-0.98, Z = 2.57, P = 0.01) both in patients having sepsis and in those who developed septic shock (RR 0.92, 95% CI 0.85-0.99, Z = 2.19, P = 0.03), while no significant difference was found in mortality with the longest follow up in patients either having sepsis (RR 0.94, 95% CI 0.89-1.00, Z = 1.93, P = 0.05), or occurrence (RR 0.83, 95% CI 0.56-1.24, Z = 0.90, P = 0.37) or reoccurrence of septic shock (RR 1.08, 95% CI 1.00-1.16, Z = 1.89, P = 0.06). CONCLUSIONS: Corticosteroids were effective in reducing the 28-day mortality in patients with severe sepsis and in those with septic shock.

The effect of hyperoxia on mortality in critically ill patients: a systematic review and meta analysis.

BACKGROUND: Studies investigating the role of hyperoxia in critically ill patients have reported conflicting results. We did this analysis to reveal the effect of hyperoxia in the patients admitted to the intensive care unit (ICU). METHODS: Electronic databases were searched for all the studies exploring the role of hyperoxia in adult patients admitted to ICU. The primary outcome was mortality. Random-effect model was used for quantitative synthesis of the adjusted odds ratio (aOR). RESULTS: We identified 24 trials in our final analysis. Statistical heterogeneity was found between hyperoxia and normoxia groups in patients with mechanical ventilation (I2 = 92%, P < 0.01), cardiac arrest(I2 = 63%, P = 0.01), traumatic brain injury (I2 = 85%, P < 0.01) and post cardiac surgery (I2 = 80%, P = 0.03). Compared with normoxia, hyperoxia was associated with higher mortality in overall patients (OR 1.22, 95% CI 1.12~1.33), as well as in the subgroups of cardiac arrest (OR 1.30, 95% CI 1.08~1.57) and extracorporeal life support (ELS) (OR 1.44, 95% CI 1.03~2.02). CONCLUSIONS: Hyperoxia would lead to higher mortality in critically ill patients especially in the patients with cardiac arrest and ELS.

Efficacy and safety of phosphodiesterase 4 inhibitors in patients with asthma: A systematic review and meta-analysis.

Phosphodiesterase 4 (PDE4) inhibitors are a novel medication approved for airway inflammatory diseases including chronic obstructive pulmonary disease. Their role and application in asthma are controversial and not defined. A comprehensive search was performed in major databases (1946-2016) using the keywords: 'phosphodiesterase 4 inhibitor' or 'roflumilast' and 'asthma'. Placebo-controlled trials reporting lung function, airway hyperresponsiveness by direct challenge, asthma control and exacerbations, and adverse events were included. Random or fixed-effects models were used to calculate odds ratios (OR) and mean differences between the two treatment groups. Statistical analyses were conducted using Mann-Whitney U-tests and Cochrane systematic review software, Review Manager. Seventeen studies were included in the systematic review, of which 14 studies were included in the meta-analysis. Except for significant statistical heterogeneity in pre- and post-challenge predicted percentage of forced expiratory volume in 1 s (FEV1 %; I2 = 72%, χ2 = 3.35, P = 0.06), there was no heterogeneity in outcome measures. Roflumilast (500 µg) significantly improved FEV1 (mean difference: 0.05, 95% CI: 0.01-0.09, Z = 2.50, P = 0.01), peak expiratory flow, asthma control and exacerbations, but showed variable effects on airway responsiveness to methacholine and a 20% fall in FEV1 .Of note, PDE4 inhibitors were accompanied with significantly higher adverse events such as headache (OR: 3.99, 95% CI: 1.65-9.66, Z = 3.07, P = 0.002) and nausea (OR: 5.53, 95% CI: 1.38-22.17, Z = 2.41, P = 0.02). In patients with mild asthma, oral PDE4 inhibitors can be considered as an alternative treatment to regular bronchodilators and inhaled controllers.

The effect of aspirin in preventing the acute respiratory distress syndrome/acute lung injury: A meta-analysis.

BACKGROUND: The effects of aspirin in preventing the occurrence of acute respiratory distress syndrome (ARDS)/acute lung injury (ALI) among adult patients are controversial. We aimed to further determine the effectiveness of aspirin in reducing the rate of ARDS/ALI. METHODS: The Pubmed, Embase, Medline, ClinicalTrials.gov, Cochrane Central Register of Controlled Trials (CENTRAL) as well as the Information Sciences Institute (ISI) Web of Science were searched for all controlled studies that research the role of aspirin in adult patients who have the risk of ARDS/ALI. The outcomes were the ARDS/ALI rate and the mortality. Cochrane systematic review software, Review Manager (RevMan), the R software for statistical computing version 3.2.0, and the metafor package were used to test the hypothesis by Mann-Whitney U test. The heterogeneity test and sensitivity analyses were conducted, and random-effects or fixed-effects model was applied to calculate odds ratio (OR) and mean difference (MD) for dichotomous and continuous data, respectively. RESULTS: Six trials involving 6562 patients were pooled in our final study. No significant heterogeneity was found in outcome measures. Aspirin could reduce the rate of ARDS/ALI (OR 0.71, 95% confidence interval (CI) 0.58-0.86) but not the mortality (OR 0.87, 95% CI 0.71-1.07). CONCLUSIONS: In patients with risk of ARDS/ALI, aspirin could provide protective effect on the rate of ARDS/ALI, but it could not reduce the mortality.

The effect of high-flow nasal cannula in reducing the mortality and the rate of endotracheal intubation when used before mechanical ventilation compared with conventional oxygen therapy and noninvasive positive pressure ventilation. A systematic review and meta-analysis.

BACKGROUND: The effects of high flow nasal cannula (HFNC) on adult patients when used before mechanical ventilation (MV) are unclear. We aimed to determine the effectiveness of HFNC when used before MV by comparison to conventional oxygen therapy (COT) and noninvasive positive pressure ventilation (NIPPV). METHODS: The Pubmed, Embase, Medline, Cochrane Central Register of Controlled Trials (CENTRAL) as well as the Information Sciences Institute (ISI) Web of Science were searched for all the controlled studies that compared HFNC with NIPPV and COT when used before MV in adult patients. The primary outcome was the rate of endotracheal intubation and the secondary outcomes were intensive care unit (ICU) mortality and length of ICU stay (ICU LOS). RESULTS: Eight trials with a total of 1084 patients were pooled in our final studies. No significant heterogeneity was found in outcome measures. Compared both with COT and NIPPV, HFNC could reduce both of the rate of endotracheal intubation (OR 0.62, 95% CI 0.38-0.99, P=0.05; OR 0.48, 95% CI 0.31-0.73, P=0.0006) and ICU mortality (OR 0.47, 95% CI 0.24-0.93, P=0.03; OR 0.36, 95% CI 0.20-0.63, P=0.0004). As for the ICU LOS, we did not find any advantage of HFNC over COT or NIPPV. CONCLUSIONS: When used before MV, HFNC can improve the prognosis of patients compared both with the COT and NIPPV.

Can body mass index predict clinical outcomes for patients with acute lung injury/acute respiratory distress syndrome? A meta-analysis.

BACKGROUND: The effects of body mass index (BMI) on the prognosis of acute respiratory distress syndrome (ARDS) are controversial. We aimed to further determine the relationship between BMI and the acute outcomes of patients with ARDS. METHODS: We searched the Pubmed, Embase, Medline, Cochrane Central Register of Controlled Trials (CENTRAL), and ISI Web of Science for trials published between 1946 and July 2016, using "BMI" or "body mass index" or "overweight" or "obese" and "ARDS" or "ALI" or "acute respiratory distress syndrome" or "acute lung injury", without limitations on publication type or language. Heterogeneity and sensitivity analyses were conducted, and a random-effects model was applied to calculate the odds ratio (OR) or mean difference (MD). Review Manager (RevMan) was used to test the hypothesis using the Mann-Whitney U test. The primary outcome was unadjusted mortality, and secondary outcomes included mechanical ventilation (MV)-free days and length of stay (LOS) in the intensive care unit (ICU) and in hospital. RESULTS: Five trials with a total of 6268 patients were pooled in our final analysis. There was statistical heterogeneity between normal-weight and overweight patients in LOS in the ICU (I 2 = 71%, χ 2 = 10.27, P = 0.02) and in MV-free days (I 2 = 89%, χ 2 = 18.45, P < 0.0001). Compared with normal weight, being underweight was associated with higher mortality (OR 1.59, 95% confidence interval (CI) 1.22, 2.08, P = 0.0006), while obesity and morbid obesity were more likely to result in lower mortality (OR 0.68, 95% CI 0.57, 0.80, P < 0.00001; OR 0.72, 95% CI 0.56, 0.93, P = 0.01). MV-free days were much longer in patients with morbid obesity (MD 2.64, 95% CI 0.60, 4.67, P = 0.01), but ICU and hospital LOS were not influenced by BMI. An important limitation of our analysis is the lack of adjustment for age, sex, illness severity, comorbid illness, and interaction of outcome parameters. CONCLUSIONS: Obesity and morbid obesity are associated with lower mortality in patients with ARDS.

The effect of sedation and/or analgesia as rescue treatment during noninvasive positive pressure ventilation in the patients with Interface intolerance after Extubation.

BACKGROUND: Sedation and/or analgesia can relieve the patient-ventilator asynchrony. However, whether sedation and/or analgesia can benefit the clinical outcome of the patients with interface intolerance is still unclear. METHODS: A retrospective study was performed on patients with interface intolerance who received noninvasive positive pressure ventilation (NIPPV) after extubation in seven intensive care units (ICU) of West China Hospital, Sichuan University. The primary outcome was rate of NIPPV failure (defined as need for reintubation and mechanical ventilation); Secondary outcomes were hospital mortality rate and length of ICU stay after extubation. RESULTS: A total of 80 patients with oral-nasal mask (90%) and facial mask (10%) were included in the analysis. 41 out of 80 patients received sedation and/or analgesia treatment (17 used analgesia, 11 used sedation and 13 used both) at some time during NIPPV. They showed a decrease of NIPPV failure rate, (15% vs. 38%, P = 0.015; adjusted odd ratio [OR] 0.29, 95% confidence interval [CI] 0.10-0.86, P = 0.025), mortality rate (7% vs. 33%, P = 0.004; adjusted OR 0.14, 95% CI 0.03-0.60, P = 0.008), and the length of ICU stay after extubation. CONCLUSION: This clinical study suggests that sedation and/or analgesia treatment can decrease the rate of NIPPV failure, hospital mortality rate and ICU LOS in patients with interface intolerance after extubution during NIPPV.

Can high-flow nasal cannula reduce the rate of reintubation in adult patients after extubation? A meta-analysis.

BACKGROUND: The effects of high flow nasal cannula (HFNC) on adult patients after extubation remain controversial. We aimed to further determine the effectiveness of HFNC in comparison to noninvasive positive pressure ventilation (NIPPV) and conventional oxygen therapy (COT). METHODS: The Pubmed, Embase, Medline, Cochrane Central Register of Controlled Trails (CENTRAL) as well as the Information Sciences Institute (ISI) Web of Science were searched for all the controlled study comparing HFNC with NIPPV and COT in adult patients after extubation. The primary outcome was rate of reintubation and the secondary outcomes were intensive care unit (ICU) mortality and length of ICU stay (ICU LOS). RESULTS: Eight trials with a total of 2936 patients were pooled in our final studies. No significant heterogeneity was found in outcome measures. Compared with COT, HFNC was associated with lower rate of reintubation (Z = 2.97, P = 0.003), and the same result was found in the comparison between HFNC and NIPPV (Z = 0.87, P = 0.38). As for the ICU mortality and ICU LOS, we did not find any advantage of HFNC over COT or NIPPV. CONCLUSIONS: In patients after extubation, HFNC is a reliable alternative of NIPPV to reduce rate of reintubation compared with COT.

Can roflumilast, a phosphodiesterase-4 inhibitor, improve clinical outcomes in patients with moderate-to-severe chronic obstructive pulmonary disease? A meta-analysis.

BACKGROUND: Effects of roflumilast on lung function, symptoms, acute exacerbation and adverse events in patients with chronic obstructive pulmonary disease (COPD) are controversial. We aimed to further clarify the efficacy and safety of roflumilast in treatment of moderate-to-severe COPD. METHODS: From 1946 to November 2015, we searched the Pubmed, Embase, Medline, Cochrane Central Register of Controlled Trials, ISI Web of Science and American College of Physician using "roflumilast" and "chronic obstructive pulmonary disease" or "COPD". Randomized controlled trials that reported forced expiratory volume in one second (FEV1), forced vital capacity (FVC), transition dyspnea index (TDI), St George's Respiratory Questionnaire (SGRQ), and incidence of COPD exacerbations and adverse events were eligible. We conducted the heterogeneities test and sensitivity analysis, and random-effects or fixed-effects model was applied to calculate risk ratio (RR) and mean difference (MD) for dichotomous and continuous data respectively. Cochrane systematic review software, Review Manager (RevMan), was used to test the hypothesis by Mann-Whitney U-test. RESULTS: Thirteen trials with a total of 14,563 patients were pooled in our final studies. Except for SGRQ (I (2) = 63 %, χ (2) = 1.71, P = 0.07) and adverse events (I (2) = 94 %, χ (2) = 0.03, P < 0.001), we did not find statistical heterogeneity in outcome measures. The pooled MD of pre- and post-bronchodilator FEV1 was 54.60 (95 % confidence interval (CI) 46.02 ~ 63.18) and 57.86 (95 % CI 49.80 ~ 65.91), and both showed significant improvement in patients with roflumilast (z = 12.47, P <0.001; z = 14.07, P < 0.001), so did in FVC (MD 90.37, 95 % CI 73.95 ~ 106.78, z = 10.79, P < 0.001). Significant alleviation of TDI (MD 0.30, 95 % CI 0.14 ~ 0.46, z = 3.67, P < 0.001) and decrease of acute exacerbation (RR 0.86, 95 % CI 0.81 ~ 0.91, z = 5.54, P < 0.001) were also identified in treatment of roflumilast, but without significant difference in SGRQ (MD -1.30, 95 % CI -3.16 ~ 0.56, z = 1.37, P = 0.17). Moreover, roflumilast significantly increased the incidence of adverse events compared with placebo (RR 1.31, 95 % CI 1.16 ~ 1.47, z = 4.32, P < 0.001). CONCLUSIONS: Roflumilast can be considered as an alternative therapy in selective patients with moderate-to-severe COPD.

Tumour markers in rheumatoid arthritis-associated interstitial lung disease.

OBJECTIVES: Interstitial lung disease (ILD) is the most common pulmonary extra-articular manifestations of rheumatoid arthritis (RA), but the pathogenesis of RA-ILD is unknown. The purpose of this study was to investigate the tumour markers levels in patients of rheumatoid arthritis-associated interstitial lung disease (RA-ILD) and to explore the diagnostic value of serum tumour markers for RA-ILD. METHODS: Twenty-eight patients with RA-ILD and 83 patients with RA only were included. Serum levels of tumour markers carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 15-3, CA125, and CA19-9 were measured. RESULTS: Tumour markers CA15-3, CA125 and CA19-9 were increased in RA-ILD patients compared with RA without ILD patients. Logistic regression analysis revealed that older age (OR=1.06, 95% CI=[1.02-1.11]) and higher CA125 (OR=1.03, 95% CI=[1.01-1.05]) related to the increased risk of RA-ILD. ROC curve analysis showed the relationship between CA125 and RA-ILD was moderate (area under ROC curve (AUC)=0.78, 95% CI=[0.68-0.88]). In addition, CA125 levels above the normal reference (<35 U/ml) raised the risk of RA-ILD (OR=6.00, 95% CI=[2.37-15.16]). CONCLUSIONS: RA patient with older age and elevated tumour markers especially CA125 levels should be evaluated to check whether there is a potential of ILD.

Can non-invasive positive pressure ventilation prevent endotracheal intubation in acute lung injury/acute respiratory distress syndrome? A meta-analysis.

The role of non-invasive positive pressure ventilation (NIPPV) in acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is controversial. The aim of this study was to investigate whether NIPPV could prevent endotracheal intubation and decrease mortality rate in patients with ALI/ARDS. Randomized controlled trials (RCT) which reported endotracheal intubation and mortality rate in patients with ALI/ARDS treated by NIPPV were identified in Pubmed, Medline, Embase, Central Cochrane Controlled Trials Register, Chinese National Knowledge Infrastructure, reference lists and by manual searches. Fixed- and random-effects models were used to calculate pooled relative risks. This meta-analysis included six RCT involving 227 patients. The results showed that endotracheal intubation rate was lower in NIPPV (95% confidence interval (CI): 0.44-0.80, z = 3.44, P = 0.0006), but no significant difference was found either in intensive care unit (ICU) mortality (95% CI: 0.45-1.07, z = 1.65, P = 0.10) or in hospital mortality (95% CI: 0.17-1.58, z = 1.16, P = 0.25). Only two studies discussed the aetiology of ALI/ARDS as pulmonary or extra-pulmonary, and neither showed statistical heterogeneity (I(2) = 0%, χ(2) = 0.31, P = 0.58), nor a significant difference in endotracheal intubation rate (95% CI: 0.35-9.08, z = 0.69, P = 0.49). In conclusion, the early use of NIPPV can decrease the endotracheal intubation rate in patients with ALI/ARDS, but does not change the mortality of these patients.

Predictive value of neutrophil-to-lymphocyte ratio and bilirubin levels in the readmission of acute exacerbation of chronic obstructive pulmonary disease.

BACKGROUND: Th aim of this study was to analyze acute exacerbation of chronic obstructive pulmonary disease (AECOPD) readmission events and to determine whether neutrophil-to-lymphocyte ratio (NLR) and bilirubin levels were associated with readmission after discharge due to AECOPD. METHODS: A total of 170 patients with AECOPD were included. Patients were stratified into the readmission group if patients had two or more readmissions within 2 years of the previous discharge, and the non-readmission group with one readmission or none within 2 years of the last discharge. Data were collected and compared between groups. The patients were separated by the cutoffs of NLR and bilirubin level. The number of all-cause readmissions within 2 years, time to first COPD-related readmission, 1-year/2-year COPD-related readmission, 1-year/2-year all-cause mortality were compared between groups, respectively. RESULTS: Compared with the readmission group, patients of the non-readmission group had a shorter length of hospital stay, more systemic corticosteroid use, higher NLR, higher bilirubin levels, and lower eosinophils counts (p < 0.05). NLR and bilirubin levels on admission had significant association with the number of all-cause readmissions (p < 0.05). Lower bilirubin was associated with an increased risk of 1-year COPD-related readmission (OR 5.063) and 2-year COPD-related readmission (OR 4.699). CONCLUSIONS: For patients with AECOPD, longer hospital stay, and less use of systemic corticosteroids may be associated with a higher risk of readmission. NLR and bilirubin levels on admission may be related to the number of all-cause readmissions. Bilirubin can be regarded as a biomarker to predict readmission rates within 2 years after discharged throughout the course of the disease.

Clinical applications of lung function tests: a revisit.

The development and clinical application of lung function tests have a long history, and the various components of lung function tests provide very important tools for the clinical evaluation of respiratory health and disease. Spirometry, measurement of the diffusion factor, bronchial provocation tests and forced oscillation techniques have found diverse clinical applications in the diagnosis and monitoring of respiratory diseases, such as chronic obstructive pulmonary disease, interstitial lung diseases and asthma. However, there are some practical issues to be resolved, including the establishment of reference values for individual test parameters and the roles of these tests in preoperative risk assessment and pulmonary rehabilitation. Novel measurements, including negative expiratory pressure, the fraction of exhaled nitric oxide and analysis of exhaled breath condensate, may provide new insights into physiological abnormalities or airway inflammation in respiratory diseases, but their clinical applications need to be further evaluated. The clinical application of lung function tests continues to face challenges, which may be overcome by further improvement of conventional techniques for lung function testing and further specification of new testing techniques.