Canadian Respiratory Journal

Introduction. There is a controversy regarding the relationship between blood eosinophil count and COPD exacerbation. We aimed to determine whether peripheral eosinophils upon COPD diagnosis could affect the frequency and severity of annual acute exacerbation of COPD (AECOPD). Methods. This prospective study was conducted on 973 newly diagnosed COPD patients who were under 1-year follow-up in a pulmonology center in Iran. The Cox proportional model, polynomial regression, and receiver operator characteristic curves were conducted to evaluate the impact of the eosinophil levels on AECOPD. A linear regression model was conducted to evaluate the continuous association of eosinophilic count with AECOPDs. Results. Patients with eosinophil >200 cells/microliter were higher pack-year smokers with more pulmonary hypertension prevalence compared to COPD patients with <200 cells/microliter. There was a positive correlation between the eosinophilic count and the frequency of AECOPDs. Eosinophil >900 cells/microliter and eosinophil >600 cells/microliter had a sensitivity of 71.1% and 64.3%, respectively, in predicting the occurrence of more than one AECOPD. Eosinophilic count cutoff of 800 cells/microliter had the highest Youden index with sensitivity and specificity of 80.2% and 76.6%, respectively, for incident AECOPD in newly diagnosed patients. Using a linear model, increasing 180 cells/microliter in serum eosinophils was associated with further exacerbation. Evaluating gender, BMI, smoking pack-year, FEV1/FVC, CAT score, GOLD score, pulmonary hypertension, annual influenza, pneumococcal vaccinations, leukocytosis, and blood eosinophils, only blood eosinophils (hazard ratio (HR) = 1.44; 95% confidence interval = 1.33–2.15; value = 0.03) and GOLD score (HR = 1.19; 95% CI = 1.30–1.52; value = 0.03) were found as independent risk factors of AECOPD >3 episodes/year. Requirement for ICU admission, invasive ventilation, and mortality rate due to AECOPDs was similar between eosinophilic and noneosinophilic groups. Conclusion. Eosinophilia upon COPD diagnosis is a factor of recurrent AECOPDs. To reduce the risk of AECOPDs and the burden of disease, clinicians may consider inhaler corticosteroids and domiciliary oxygen with a lower threshold for eosinophilic-COPD patients regardless of their clinical status.

Background. Limited data are available about the clinical outcomes of AECOPD patients with respiratory acidosis treated with HFNC versus NIV. Methods. We conducted a retrospective study to compare the efficacy of HFNC with NIV as initial ventilation support strategy in AECOPD patients with respiratory acidosis. Propensity score matching (PSM) was implemented to increase between-group comparability. Kaplan–Meier analysis was utilized to evaluate differences between the HFNC success, HFNC failure, and NIV groups. Univariate analysis was performed to identify the features that differed significantly between the HFNC success and HFNC failure groups. Results. After screening 2219 hospitalization records, 44 patients from the HFNC group and 44 from the NIV group were successfully matched after PSM. The 30-day mortality (4.5% versus 6.8%, ) and 90-day mortality (4.5% versus 11.4%, ) did not differ between the HFNC and NIV groups. Length of ICU stay (median: 11 versus 18 days, ), length of hospital stay (median: 14 versus 20 days, ), and hospital cost (median: 4392 versus 8403 $USD, ) were significantly lower in the HFNC group compared with NIV group. The treatment failure rate was much higher in the HFNC group than in the NIV group (38.6% versus 11.4%, ). However, patients who experienced HFNC failure and switched to NIV showed similar clinical outcomes to those who first received NIV. Univariate analysis showed that log NT-proBNP was an important factor for HFNC failure (). Conclusions. Compared with NIV, HFNC followed by NIV as rescue therapy may be a viable initial ventilation support strategy for AECOPD patients with respiratory acidosis. NT-proBNP may be an important factor for HFNC failure in these patients. Further well-designed randomized controlled trials are needed for more accurate and reliable results.

Background. Pulmonary sarcoidosis predominantly affects the upper lung zones but sometimes affects the lower lung zones. We hypothesised that patients with lower lung zone-dominant sarcoidosis had lower baseline forced vital capacity, progressive restrictive lung function decline, and higher long-term mortality. Methods. We retrospectively reviewed clinical data including the pulmonary function tests of 108 consecutive patients with pulmonary sarcoidosis pathologically confirmed by lung and/or mediastinal lymph node biopsy from 2004 to 2014 from our database. Results. Eleven patients (10.2%) with lower lung zone-dominant sarcoidosis were compared with 97 patients with nonlower lung zone-dominant sarcoidosis. The median age of the patients with lower dominance was significantly older (71 vs. 56, ). The patient with lower dominance had a significantly lower baseline percent forced vital capacity (FVC) (96.0% vs. 103%, ). The annual change in FVC was −112 mL in those with lower dominance vs. 0 mL in nonlower dominance (). Fatal acute deterioration was observed in three patients (27%) in the lower dominant group. Overall survival in the lower dominant group was significantly worse. Conclusions. Patients with lower lung zone-dominant sarcoidosis had an older age and lower baseline FVC with disease progression and acute deterioration associated with higher long-term mortality.

Background. There is no radiological measurement to estimate the severity of pediatrics juvenile dermatomyositis (JDM) with interstitial lung disease (ILD). We validated the effectiveness of CT scoring assessment in JDM patients with ILD. Aim. To establish a CT scoring system and calculate CT scores in JDM patients with ILD and to determine its reliability and the correlation with Krebs von den Lungen-6 (KL-6). Methods. The study totally enrolled 46 JDM-ILD patients and 16 JDM without ILD (non-ILD, NILD) patients. The chest CT images (7.0 ± 3.6 years; 32 male and 30 female) were all analyzed. CT scores of six lung zones were retrospectively calculated, included image pattern score and distribution range score. Image pattern score was defined as follows: increased broncho-vascular bundle (1 point); ground glass opacity (GGO) (2 points); consolidation (3 points); GGO with bronchiectasis (4 points); consolidation with bronchiectasis (5 points); and honeycomb lung (6 points). Distribution range score was defined as no infiltrate (0 point); <30% (1 point); 30%–60% (2 points); and ≥60% (3 points). Two pediatric radiologists reviewed all CT images independently. The ROC curve was established, and the optimal cutoff score for severity discrimination was set. Results. The agreement between two observers was excellent, and the ICC was 0.930 (95% CI 0.882–0.959, ). CT score and KL-6 level had a positive linear correlation (r = 0.784, ). However, the correlation between CT scores of different lung zone and KL-6 level was different. The KL-6 cut off level suggested for JDM with ILD was 209.0 U/ml, with 73.9% sensitivity and 87.5% specificity, and the area under curve was (AUC) 0.864 (). Conclusion. The CT scoring system we established, as a semiquantitative method, can effectively evaluate ILD in JDM-PM patients and provide reliable evidence for treatment.

Aim. To investigate the association between serum bilirubin and disease severity in patients with pneumoconiosis. Methods. The study comprised 45 patients with pneumoconiosis retrospectively; all pneumoconiosis patients were classified into I, II, and III stage according to the radiological severity. Results. Serum direct bilirubin levels were significantly lower in III stage pneumoconiosis patients than those in I/II stage (p = 0.012) but not serum indirect bilirubin. Serum direct bilirubin was negatively correlated with radiological severity in patients with pneumoconiosis (r = −0.320; p = 0.032); by multiple linear-regression analysis, we observed that serum direct bilirubin levels had independent association with radiological severity in patients with pneumoconiosis (beta = −0.459; p = 0.005). Conclusions. Serum direct bilirubin levels are negatively associated with disease severity in patients with pneumoconiosis.

Background. High-flow nasal cannula (HFNC) is an oxygen delivery method shown to reduce the risk of intubation and mortality in patients with type 1 respiratory failure. The ROX-index score can predict HFNC failure. This study aims to evaluate sequential ROX-index assessments as predictors of HFNC failure and mortality. Methods. Prospective observational single-center study including all adult patients with positive SARS-CoV-2 PCR placed under HFNC from 1st November 2020 to 31st May 2021, and patients with hemodynamic instability or unable to tolerate HFNC were excluded. The primary endpoint was successful HFNC de-escalation. Results. In univariate analysis, HFNC de-escalation was associated with younger age (59.2 ± 14 vs. 67.7 ± 10.5 and ), lower levels of serum lactate (1.1 vs. 1.5 and ), and higher ROX-index at 12 hrs (5.09 vs. 4.13 and ). ROC curve analysis of ROX-index at 12 hrs yielded a c-statistic of 71.2% (95% CI 61.6–80.9 and ). ROX-index at 12 hrs and age retained significance in multivariate analysis. Using an optimal cutoff point of 4.43, we calculated a sensitivity of 64.5% and specificity of 69.6%. In univariate survival analysis, older age (68.8 ± 9.7 vs. 58.9 ± 13.9 and ), greater creatinine values (0.96 vs. 0.84 and ), greater SOFA score (), and a lower 12 hrs ROX-index (4.22 vs. 4.95 and ) were associated with hospital mortality. The SOFA score and age retained significance in multivariate survival analysis. Conclusion. ROX-index is proven to be a valuable and easy-to-use tool for clinicians in the assessment of COVID-19 patients under HFNC.