Thank you for tuning in to the Editor’s Highlight Podcast for the January 2023 issue of the journal CHEST®. There is a great lineup of diverse content in this month’s issue.
Over the next 15 minutes, I will provide a brief overview of key manuscripts published in each of our content areas.
Starting with our Asthma content area, controlled studies showing the outcomes of extracorporeal membrane oxygenation (ECMO) as salvage therapy for asthma exacerbations with respiratory failure have not been performed. In this issue, Zakrajsek and colleagues report the findings of a retrospective, observational cohort study designed to determine if treatment with ECMO is associated with lower mortality in refractory asthma exacerbations with respiratory failure. Using a national administrative data set that includes 25% of US hospitalizations, 13,714 patients were found who met study criteria, including 127 treated with ECMO. ECMO was associated with reduced mortality in covariate-adjusted (OR 0.33), propensity score-adjusted (OR 0.36), and propensity score-matched (OR 0.48) models. ECMO was also associated with increased hospital costs but not ICU or hospital length of stay or time using mechanical ventilation. These results suggest ECMO may be an important salvage therapy for individuals with refractory asthma exacerbations with respiratory failure.
Next is our Chest Infections content area. Few large-scale studies have shown the efficacy of tobramycin nebulization in bronchiectasis. In this issue, Guan and colleagues report the findings from a phase 3, 16-week, multicenter, randomized, double-blind, placebo-controlled trial designed to determine if tobramycin inhalation solution could effectively reduce sputum Pseudomonas (P.) aeruginosa density, and improve bronchiectasis-specific quality of life, in patients with bronchiectasis and P. aeruginosa infection. Three hundred thirty-nine patients were included in the intention to treat population. Those receiving nebulized tobramycin inhalation solution had a significantly greater reduction in P. aeruginosa density, a greater improvement in the quality-of-life bronchiectasis respiratory symptoms score, and a significant reduction in sputum volume and purulence, and a greater percentage of patients became culture negative. These results suggest that nebulized tobramycin inhalation solution could be an effective treatment option for patients with bronchiectasis with P. aeruginosa infection. Also in this section is an original research study that assesses the treatment effects of long-term azithromycin in children with bronchiectasis unrelated to cystic fibrosis and another reporting findings from a development and validation study of a machine learning model for mortality prediction in patients with community-acquired pneumonia. Completing this section is a CHEST Review article on the changing epidemiology of cystic fibrosis and the implications for adult care.
On to our COPD content area. It is unclear if inhaled corticosteroid (ICS) therapy can reduce all-cause mortality in patients or subgroups of patients with COPD. In this issue, Chen and colleagues report the results of a systematic review and meta-analysis to determine if inhaled therapy containing ICSs reduces all-cause mortality. Sixty randomized controlled trials including 103,000 patients were included. They found that ICSs, particularly when included as triple therapy, were associated with a reduction in all-cause mortality among patients with COPD (OR 0.73). Treatment duration of >6 months (OR 0.9), the use of medium-dose ICSs (0.71), the use of low-dose ICSs (0.88), and the use of budesonide (0.75) were all associated with a reduction in all-cause mortality. Eosinophil counts >200/uL were the strongest predictor of benefit (OR 0.58). Other predictors included eosinophil percentage >2%, history of two or more moderate and severe exacerbations, Global Initiative for Chronic Obstructive Lung Disease stages III or IV, age younger than 65, and BMI of >25 kg/m2. These results show that ICS-containing regimens, particularly as part of triple therapy for treating COPD, are associated with reduced all-cause mortality, with eosinophil counts >200/uL being the strongest predictor of benefit.
Next is our Critical Care content area. Limited available data suggest wide variation in the use of bronchoscopy for the evaluation of acute respiratory failure. In this issue, Wayne and colleagues report findings from an observational cohort study of patients treated with invasive mechanical ventilation using the National Inpatient Sample, designed to determine the frequency and temporal trend of bronchoscopy use among patients with acute respiratory failure. More than 6.1 million patients treated with invasive mechanical ventilation were included, 609,405 of whom underwent bronchoscopy. The percentage of patients undergoing bronchoscopy increased from 9.5% in 2012 to 10.8% in 2018, with variability between hospitals in 2018 ranging from 0% to 57.1%. Sixteen percent of the variation was explained at the hospital level across the 1,787 hospitals that were included. These findings confirm an increase in bronchoscopy use in patients with acute respiratory failure requiring invasive mechanical ventilation over time, with a large variation suggesting unwarranted practice variation and opportunities to clarify who benefits from bronchoscopy. Also in this section is an original research article assessing failure rates during a 120-minute spontaneous breathing trial for children who passed a 30-minute trial, a research letter evaluating the relationship between norepinephrine-equivalent dose of vasopressors within 24 hours of the onset of septic shock and in-hospital mortality, and a CHEST Review of the psychological morbidity after COVID-19 critical illness.
On to our Diffuse Lung Disease content area. Risk factors and clinical outcomes of quantitative interstitial abnormality progression over time have not been characterized. In this issue, Choi and colleagues evaluated quantitative interstitial abnormality progression from 4,635 patients with follow-up imaging in the COPDGene cohort and 1,307 participants in the Pittsburgh Lung Screening Study cohort to identify associations between progression and lung function, exercise capacity, and mortality, as well as demographic and genetic risk factors for progression. They identified age at enrollment, female sex, current smoking status, and the MUC5B minor allele as being associated with quantitative interstitial abnormality progression. Progression over time was associated with a decline in FVC and 6-minute walk distance and an increase in mortality (HR 1.28-1.69). These results suggest that longitudinal measurement of quantitative interstitial abnormalities may help to identify people at risk for adverse events and most likely to benefit from early intervention. Completing this section is an original research article assessing the impact of refining the Lung Allocation Score on discrimination performance.
Our Education and Clinical Practice content area is next. The lung ultrasound score was developed prior to COVID-19. The feasibility, and correlation with volumetric measures of severity on CT imaging, of an alternative lung ultrasound method based on grading the percentage of extension of typical signs of COVID-19 pneumonia was assessed in this issue by Volpicelli and colleagues. Data from 179 patients were included. Feasibility of the exam was 100%, with a time to perform of 5 minutes. There was a positive correlation between this extension of the lung ultrasound score and the CT volume, both of which showed a negative correlation with the PaO2/FiO2 ratio. These results suggest a practical extension of the lung ultrasound score can assess the severity of lung lesions and reflect the severity of respiratory failure. Completing this section is a How I Do It review of the coordination of care for expiratory central airway collapse.
Next is our Pulmonary Vascular content area. Sex differences in the use, outcomes, and health care resource utilization of patients with pulmonary embolism (PE) undergoing percutaneous pulmonary artery thrombectomy are not well characterized. In this issue, Agarwal and colleagues report findings from a retrospective, cross-sectional study using national inpatient claims data to determine whether there are sex differences in outcomes for patients diagnosed with PE who undergo percutaneous pulmonary artery thrombectomy. Five thousand one hundred sixty patients with a diagnosis of PE who underwent percutaneous pulmonary artery thrombectomy were identified. Female patients showed higher procedural bleeding, required more blood transfusions, experienced more vascular complications, were less likely to be discharged home, and had a higher in-hospital mortality compared with men. These results suggest there is higher morbidity and in-hospital mortality in women with PE undergoing percutaneous thrombectomy than men, prompting future evaluation of the causes and potential impact of care changes. Completing this section is an original research article exploring differences in metabolomics profiles between patients with scleroderma-related pulmonary arterial hypertension and idiopathic pulmonary hypertension and their relationship with functional capacity.
Our Sleep Medicine content area is next. The underlying mechanisms of reduced exercise capacity in patients with OSA hypopnea syndrome (OSAHS) are unclear. In this issue, Elbehairy and colleagues report findings from a cross-sectional study in which 14 patients with moderate to severe OSAHS and 10 matched control participants underwent pulmonary function testing, noninvasive heart and vascular testing, and cardiopulmonary exercise testing to evaluate the underlying mechanisms of reduced exercise capacity in untreated patients with OSAHS. Minute ventilation, ventilatory equivalent for CO2 output, and dead space to tidal volume ratio were greater in patients than control participants during exercise. The reduction in dead space to tidal volume ratio during exercise was greater in control participants. Age, pulmonary wave velocity, and mean pulmonary artery pressure explained approximately 70% of the variance in peak work rate, whereas rest-to-peak change in dead space to tidal volume ratio and pulmonary wave velocity predicted dyspnea. These findings identified pulmonary gas exchange abnormalities during exercise, and resting systemic vascular dysfunction, that help to explain reductions in exercise capacity and increased dyspnea in patients with OSAHS. Completing this section is a Point/Counterpoint debate about the clinical utility of OSA phenotypes.
Next is our Thoracic Oncology content area. Overdiagnosis and treatment of lung cancer by low-dose CT (LDCT) screening has been identified as a potential harm of screening. In this issue, Wang and colleagues evaluated changes in stage-specific and histologic type-specific incidence, mortality, and incidence rate ratio in a population where LDCT was used widely in employee health examinations to determine if the increased use of LDCT in low-risk populations led to lung cancer overdiagnosis. They found lung cancer incidence increased rapidly in women from 2011 onward (12% annually), whereas mortality declined. This incidence trend was accounted for by increased adenocarcinoma cases. Early-stage incidence rose 16.1 per 100,000 women, but there was no significant decline in late-stage cancer. The incidence rate ratio was highest in the most recent period and increased most in young women. These results suggest the possibility of population-level overdiagnosis of lung cancer in Chinese women resulting from LDCT screening in low-risk populations, highlighting the need for caution in expansion of lung cancer screening eligibility. Also in this section is a research letter exploring the value of shared decision-making during a lung cancer screening visit and another describing a biomarker-based approach for the determination of sample adequacy during endobronchial ultrasound-guided transbronchial needle aspiration.
Finally, I encourage you to take a look at our Humanities in Chest Medicine section, where you will find a multi-institutional, exploratory, qualitative research study of “No Escalation of Treatment” designations and an Exhalations piece titled, “Dress Rehearsal.”
Our case series publications for the month provide novel and educational cases to help improve your clinical skills.
I hope you enjoy reading all of the high-quality content available in this month’s issue of the journal CHEST. As always, I am grateful to the authors of this work, to the reviewers who volunteered their time to improve the quality of these manuscripts, and to our editorial board for guiding everything that we do. Until next month, I hope you enjoy the January issue.