Clinical features and outcomes of persons with cystic fibrosis and nocardia isolation: a systematic review.

BACKGROUND: Recurrent respiratory infections are a leading cause of morbidity and mortality in persons with Cystic Fibrosis (pwCF). Recently, the emergence of Nocardia species as a potential pathogen in CF has raised questions about its role and management, as its clinical significance and the optimal patient management remain unclear in current clinical practice. This review explores the clinical implications of Nocardia species in patients with Cystic Fibrosis (pwCF) through a comprehensive literature review. Key objectives include assessing its impact on lung function, identifying colonization risk factors, and evaluating an appropriate treatment. METHODS: The literature review, conducted until June 30, 2023, from databases like MEDLINE, PubMed, Embase, and Cochrane, included 16 articles involving 89 pwCF with Nocardia species isolation according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline recommendations. Articles reporting Nocardia prevalence and symptoms based on original data in adult and paediatric pwCF were included. All the retrieved studies were observational ones, thus, they were categorized by study type as case report and case series. RESULTS: Overall 89 pwCF and Nocardia species isolation were included: 42 children and 47 adults. Where reported, we found these main following bacterial species: Nocardia asteroides (35%, 23/64), Nocardia farcinica (21%, 14/64), Nocardia tranvalensis (13%, 8/64) and Nocardia cyriacigeorgica (11%, 7/64). A co-infection was reported in 85% of patients (61/72). Of patients whose lung function was reported before and after Nocardia isolation, 23% (16/68) showed a decline in FEV1. Above all, 82 patients were treated at least once after isolation of Nocardia strain. In 93% (77/82) of cases, treatment was started immediately upon isolation. Antibiotic treatment was performed per os or intravenously depending on the clinical condition of the individual patient. Nocardia eradication was attempted in only 32 cases out of 82, and 78% (25/32) of these patients were successfully eradicated after one or more courses of antibiotics. Death was reported in 3 patients, 2 of which were children. CONCLUSION: In general the isolation of the bacteria does not necessarily imply therapy, but patients need to be monitored closely to assess the possible occurrence of active infection. The treatment seems to be indicated in patients showing lung involvement with the possible appearance of pneumonia, pleural effusion, fever, cough, or a decrease in FEV1, as in the case that we described, or in patients undergoing pulmonary transplantation.

Effects of aerobic exercise-based pulmonary rehabilitation on quality of life in pediatric asthma: A systematic review and meta-analysis.

BACKGROUND: Pediatric asthma poses a significant global health burden, impacting the well-being and daily lives of affected children. Aerobic exercise-based pulmonary rehabilitation emerges as a promising intervention to address the multifaceted challenges faced by pediatric asthma patients. OBJECTIVES: The purpose of this systematic review and meta-analysis was to comprehensively evaluate the effects of aerobic exercise-based pulmonary rehabilitation on pulmonary function and quality of life in pediatric asthma patients. METHODS: Randomized controlled trials (RCTs) involving pediatric participants (5-18 years) were included. Aerobic exercise program-based pulmonary rehabilitation interventions were assessed for their impact on actual and percentage predicted values of lung volumes and flow rates such as forced vital capacity (FVC), maximum mid-expiratory flow (FEF25-75), peak expiratory flow (PEF), forced expiratory volume in one second (FEV1), FEV1/FVC, and on quality of life (QoL) measures. A systematic search of databases, hand-searching, and consultation with experts identified relevant studies. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines guided study selection, data extraction, and quality assessment. RESULTS: The systematic review included 20 studies with diverse exercise interventions and outcomes. The meta-analysis using fixed-effects model showed that there was a significant improvement in FVC (% predicted) [SMD= 0.30, 95 %CI: 0.13, 0.48] and FEF25-75 (% predicted) [SMD= 0.31, 95 %CI: 0.03, 0.58] in the experimental group compared with the control group. Furthermore, using a random-effects model involving 12 studies, significant increases in the QoL [SMD= 0.70, 95 %CI: 0.14, 1.26] were found in the exercise group. Due to inter-study heterogeneity, additional analyses were conducted. Publication bias analysis indicated robustness, with no significant asymmetry in funnel plots. CONCLUSION: Aerobic exercise-based pulmonary rehabilitation significantly enhances pulmonary function and quality of life in pediatric asthma patients. The findings, supported by improvements in FVC and FEF25-75, demonstrate the efficacy of these interventions. Quality of life measures also showed notable improvements. Despite inter-study heterogeneity, the results are robust, suggesting that aerobic exercise should be considered a valuable non-pharmacological strategy in managing pediatric asthma.

Mediated relationship between Vitamin D deficiency and reduced pulmonary function by copper in Taiwanese young adults.

BACKGROUND: Vitamin D deficiency is prevalent worldwide and associated with worse outcomes in various lung diseases. This study examines the association between vitamin D deficiency and pulmonary function in healthy young adults. METHODS: This prospective cohort study (2017-2019) explored the impact of vitamin D deficiency on pulmonary function in a community-based young adult population. Pulmonary function was assessed via spirometry, with serum 25-hydroxyvitamin D [25(OH)D] and urinary copper levels quantified. Multivariate regression was used to estimate the relationship between vitamin D levels and lung function, with mediation analysis evaluating copper's role. RESULTS: The study included 1034 participants, average age 33.45 years, 41.93 % male. The median 25(OH)D level was 19.20 ng/mL (Interquartile Range: 13.48-24.90 ng/mL). Over half (54.74 %) had 25(OH)D levels below 20 ng/mL. Higher 25(OH)D levels were associated with better forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). Trends suggested subgroup differences, but these were not statistically significant, indicating a consistent effect of 25(OH)D on pulmonary function across groups. SEM analysis suggested urinary copper as a mediator between 25(OH)D levels and FVC. CONCLUSION: Vitamin D deficiency is significantly associated with reduced pulmonary function in young adults in Taiwan.

Lung function measurements in the Greenlandic Inuit population: results from the Greenlandic health survey 2017-2019.

Background: Little is known about lung function in Inuit. The aim of this study was to describe lung function and the prevalence of obstructive and restrictive lung disease among Inuit in Greenland. Methods: During the 2017-2019 Health Survey, spirometry, with forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio in liters (L), and percent of predicted value (pred%) were recorded according to Global Lung function Initiative standard reference values (GLI). Smoking history was obtained. Obstructive spirometry was defined as FEV1/FVC <70%. Restrictive spirometry was proposed by FVC < 80% and FEV1/FVC >90%. Results: Based on validated spirometries, 795/2084 persons were included in this cross-sectional, descriptive study. Of those, 54.6% were current- and 27.7% former smokers. In Inuit, normal lung function was higher than predicted GLI (FEV1 107.2 pred%/FVC 113.5 pred%). In total, 106 (13.3%) were found to have an obstructive lung function measurement and 11 (1.4%) had a restrictive pattern. Among current smokers, the prevalence of obstructive lung function was 16.4%. An accelerated decline in lung function was observed > 50 years old (y.o), compared to <50 y.o. Conclusion: This study indicates that Inuit has higher absolute lung function values than standard GLI, despite the large proportion of smokers, which indicate a need for Inuit reference values in the daily clinical praxis. The high prevalence of obstructive lung function and rapid decline in lung function indicates the need for fucus on health issues that may affect lung health in Greenland.

Complications of chest wall around malignant tumors: differences based on reconstruction strategy.

BACKGROUND: Malignant chest wall tumors need to be excised with wide resection to ensure tumor free margins, and the reconstruction method should be selected according to the depth and dimensions of the tumor. Vascularized tissue is needed to cover the superficial soft tissue defect or bone tissue defect. This study evaluated differences in complications according to reconstruction strategy. METHODS: Forty-five patients with 52 operations for resection of malignant tumors in the chest wall were retrospectively reviewed. Patients were categorized as having superficial tumors, comprising Group A with simple closure for small soft tissue defects and Group B with flap coverage for wide soft tissue defects, or deep tumors, comprising Group C with full-thickness resection with or without mesh reconstruction and Group D with full-thickness resection covered by flap with or without polymethyl methacrylate. Complications were evaluated for the 52 operations based on reconstruction strategy then risk factors for surgical and respiratory complications were elucidated. RESULTS: Total local recurrence-free survival rates in 45 patients who received first operation were 83.9% at 5 years and 70.6% at 10 years. The surgical complication rate was 11.5% (6/52), occurring only in cases with deep tumors, predominantly from Group D. Operations needing chest wall reconstruction (p = 0.0016) and flap transfer (p = 0.0112) were significantly associated with the incidence of complications. Operations involving complications showed significantly larger tumors, wider areas of bony chest wall resection and greater volumes of bleeding (p < 0.005). Flap transfer was the only significant predictor identified from multivariate analysis (OR: 10.8, 95%CI: 1.05-111; p = 0.0456). The respiratory complication rate was 13.5% (7/52), occurring with superficial and deep tumors, particularly Groups B and D. Flap transfer was significantly associated with the incidence of respiratory complications (p < 0.0005). Cases in the group with respiratory complications were older, more frequently had a history of smoking, had lower FEV1.0% and had a wider area of skin resected compared to cases in the group without respiratory complications (p < 0.05). Preoperative FEV1.0% was the only significant predictor identified from multivariate analysis (OR: 0.814, 95%CI: 0.693-0.957; p = 0.0126). CONCLUSIONS: Surgical complications were more frequent in Group D and after operations involving flap transfer. Severe preoperative FEV1.0% was associated with respiratory complications even in cases of superficial tumors with flap transfer.

Model-based comparisons of post-treatment free IgE and FEV1 between omalizumab asthma dosing tables in the United States and European Union.

AIMS: Omalizumab is an anti-immunoglobulin E (IgE) monoclonal antibody that was first approved by the United States (US) Food and Drug Administration (FDA) for the treatment of allergic asthma in 2003. The pivotal trials supporting the initial approval of omalizumab used dosing determined by patient's baseline IgE and body weight, with the goal of reducing the mean free IgE level to approximately 25 ng/mL or less. While the underlying parameters supporting the dosing table remained the same, subsequent studies and analyses have resulted in approved alternative versions of the dosing table, including the European Union (EU) asthma dosing table, which differs in weight bands and maximum allowable baseline IgE and omalizumab dose. In this study, we leveraged modelling and simulation approaches to predict and compare the free IgE reduction and forced expiratory volume in 1 second (FEV1) improvement with omalizumab dosing based on the US and EU asthma dosing tables. METHODS: Previously established population pharmacokinetic-IgE and IgE-FEV1 models were used to predict and compare post-treatment free IgE and FEV1 based on the US and EU dosing tables. Clinical trial simulations (with virtual asthma populations) and Monte Carlo simulations were performed to provide both breadth and depth in the comparisons. RESULTS: The US and EU asthma dosing tables were predicted to result in generally comparable free IgE suppression and FEV1 improvement. CONCLUSIONS: Despite the similar free IgE and FEV1 outcomes from simulations, this has not been clinically validated with respect to the registrational endpoint of reduction in annualized asthma exacerbations.

The Abbreviated Methacholine Challenge Test is Safe for Children.

OBJECTIVE: To evaluate the safety of an abbreviated methacholine challenge test (MCT) protocol in children. STUDY DESIGN: This prospective, observational study enrolled children aged 6 through 18 years referred for the MCT. The abbreviated protocol was initiated with a methacholine dose of 0.03 mg/ml and escalated in fourfold increments, unless the forced expiratory volume at 1 second decline exceeded 10%, at which point the next dose was only doubled. The safety of this abbreviated approach was assessed by monitoring adverse events, and specifically, decreases in forced expiratory volume at 1 second over 40%, hypoxemia, or uncontrollable cough. The number of methacholine doses and test duration were recorded and compared with estimated outcomes derived from the full-length MCT protocol. RESULTS: One hundred twelve participants, aged 13.7 years (±3.3), successfully completed the protocol. Fifty-seven (51%) presented a positive MCT response. No significant clinical adverse events were observed. Of all participants, 2.7% exhibited an exaggerated response, in line with previously reported findings for the full-length protocol. The abbreviated approach resulted in an estimated average time-savings of 18:19 minutes per participant, thus reducing test length by 22:47 minutes for a negative MCT and by 14:34 minutes for a positive outcome. CONCLUSIONS: This abbreviated MCT protocol is safe for children and effectively shortens the duration of the MCT.

Comparison of race-specific and race-neutral GLI spirometric reference equations with an Indian reference equation.

BACKGROUND: Despite the increasing popularity and use of Global Lung Function Initiative (GLI) spirometric reference equations, the appropriateness of the race-specific and race-neutral GLI spirometric reference models among the Indian population has not been systematically investigated. METHODS: In this cross-sectional analysis, we used spirometric measurements of 1123 healthy Indian adults (≥18 years of age). We computed reference values and z-scores for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and FEV1/FVC from race-specific and race-neutral GLI reference equations as well as from a widely used Indian reference equation. We studied heterogeneity between GLI equations and the Indian equations using Bland-Altman analysis, and the differences between the reference and observed values were compared using the Friedman test. RESULTS: In Bland-Altman analysis, significant heterogeneity in FVC and FEV1 between race-specific and Indian equations was observed (bias: 10.4 % and 14.1 %, respectively), with less bias for FEV1/FVC (3.76 %). The race-neutral equations showed almost similar bias (9.8 %, 13.8 %, and 3.8 % for FVC, FEV1, and FEV1/FVC, respectively). Median differences in race-specific reference values from observed values for FVC and FEV1 were 0.49L and 0.44L, respectively, decreasing slightly with race-neutral equations (0.46L and 0.43L) whereas Indian models showed minimal differences (FVC: 0.10L, FEV1: 0.05L). Z-scores for FVC and FEV1 were significantly different between race-specific and race-neutral GLI equations, and both differed from Indian equations. CONCLUSION: Both race-specific and race-neutral GLI reference equations are significantly different from the Indian equations, which underscores the importance of determining the suitability of global reference models before being used indiscriminately.

Pollution exposure in the first 3 months post transplant is associated with lower baseline FEV1 and higher CLAD risk.

BACKGROUND: Exposure to air pollution post-lung transplant has been shown to decrease graft and patient survival. This study examines the impact of air pollution exposure in the first 3 months post-transplant on baseline (i.e., highest) forced expiratory volume in 1 second (FEV1) achieved and development of chronic lung allograft dysfunction (CLAD). METHODS: Double-lung transplant recipients (n = 82) were prospectively enrolled for comprehensive indoor and personal environmental monitoring at 6- and 12-week post transplant and followed for >4 years. Associations between clinical and exposure variables were investigated using an exposomics approach followed by analysis with a Cox proportional hazards model. Multivariable analyses were used to examine the impact of air pollution on baseline % predicted FEV1 (defined as the average of the 2 highest values post transplant) and risk of CLAD. RESULTS: Multivariable analysis revealed a significant inverse relationship between personal black carbon (BC) levels and baseline % FEV1. The multivariable model indicated that patients with higher-than-median exposure to BC (>350 ng/m3) attained a baseline % FEV1 that was 8.8% lower than those with lower-than-median BC exposure (p = 0.019). Cox proportional hazards model analysis revealed that patients with high personal BC exposure had a 2.4 times higher hazard risk for CLAD than patients with low BC exposure (p = 0.045). CONCLUSIONS: Higher personal BC levels during the first 3 months post-transplant decrease baseline FEV1 and double the risk of CLAD. Strategies to reduce BC exposure early following a lung transplant may help improve lung function and long-term outcomes.

The role of FEV1/FVC in the prediction of acute exacerbation of COPD.

BACKGROUND: Whether the ratio of forced expiratory volume in 1 s to forced vital capacity (FEV1/FVC) can be used as a biomarker to predict the risk of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is unclear. METHODS: To investigate the predictive role of FEV1/FVC for AECOPD, we analyzed data from an observational and multicenter cohort study of 2043 patients with COPD in KOREA. Exposures were post-bronchodilator FEV1/FVC and/or percentage predicted FEV1 (FEV1%pred). The outcome was the development of AECOPD during the first year of follow-up. RESULTS: During the first year of follow-up, the proportion of patients who developed AECOPD increased as FEV1/FVC decreased (P < 0.01). FEV1/FVC and FEV1%pred had similar predictive power for AECOPD, with optimal predictive cut-offs of approximately 0.5 for FEV1/FVC and 50 % for FEV1%pred. When the participants were classified into groups based on these cut-offs, compared with a high both-lung function group (FEV1/FVC≥0.5 and FEV1%pred≥50 %), the low-FEV1 group (FEV1/FVC≥0.5 and FEV1%pred<50) had a modestly increased risk of severe AECOPD (adjusted odds ratio[aOR] = 3.12; 95 % confidence interval[CI] = 1.59-6.16), while the risk of severe AECOPD was the highest in the low both-lung function group (FEV1%pred<50 % and FEV1/FVC<0.5) (aOR = 5.16; 95 % CI = 3.34-7.97). CONCLUSIONS: FEV1/FVC is a spirometric biomarker predictive of AECOPD. In countries where FEV1%pred is not available for their population, FEV1/FVC could be used as a biomarker for assessing the risk of AECOPD. In countries where accurate FEV1%pred is available, both FEV1%pred and FEV1/FVC could be used to provide additional information to assess the risk of AECOPD. KEY MESSAGE: This study showed that FEV1/FVC had similar predictive power for AECOPD compared with percentage predicted FEV1. Furthermore, the use of both FEV1 and FEV1/FVC provides additional information for the risk assessment of AECOPD.

Factors associated with pulmonary function decline of patients in the cystic fibrosis registry of Turkey: A retrospective cohort study.

BACKGROUND: The decline in pulmonary function is a predictor of disease progression in patients with cystic fibrosis (CF). This study aimed to determine the decline rate of percent predicted forced expiratory volume in 1 s (ppFEV1) based on the data of the CF Registry of Turkey. The secondary aim was to investigate the risk factors related to the decline in ppFEV1. METHODS: A retrospective cohort study of CF patients over 6 years old, with pulmonary function data over at least 2 years of follow-up was extracted from the national CF registry for years 2017-2019. Patients were classified according to disease severity and age groups. Multivariate analysis was used to predict the decline in ppFEV1 and to investigate the associated risk factors. RESULTS: A total of 1722 pulmonary function test results were available from 574 patients over the study period. Mean diagnostic age was older and weight for age, height for age, and body mass index z scores were significantly lower in the group of ppFEV1 < 40, while chronic Pseudomonas aeruginosa (p < .001) and mucoid P. aeruginosa colonization (p < .001) were significantly higher in this group (p < .001). Overall mean annual ppFEV1 decline was -0.97% (95% confidence interval [CI] = -0.02 to -1.92%). The mean change of ppFEV1 was significantly higher in the group with ppFEV1 ≥ 70 compared with the other (ppFEV1 < 40 and ppFEV1: 40-69) two groups (p = .004). Chronic P. aeruginosa colonization (odds ratio [OR] = 1.79 95% CI = 1.26-2.54; p = .01) and initial ppFEV1 ≥ 70 (OR = 2.98 95% CI = 1.06-8.36), p = .038) were associated with significant ppFEV1 decline in the whole cohort. CONCLUSIONS: This data analysis recommends close follow-up of patients with normal initial ppFEV1 levels at baseline; advocates for early interventions for P. aeruginosa; and underlines the importance of nutritional interventions to slow down lung disease progression.

Associations of Cardiorespiratory Fitness and Muscular Endurance Fitness With Pulmonary Function in Physically Active Young Adults.

RATIONALE: While the beneficial effects of physical fitness on general health are well-documented, the specific relationship between different types of physical fitness, particularly cardiorespiratory fitness (CRF) and muscular endurance fitness (MEF), and lung function in physically active young adults remains less explored. OBJECTIVE: This study investigated the relationship between CRF and MEF, and their correlation with lung function in physically active young adults. METHODS: This cross-sectional study involved a cohort of 1227 physically active young adults without lung diseases. Lung function was assessed using FEV1, FVC, and FEV1/FVC measurements. The 3000-m run was used to assess CRF, and the 2-min push-up and sit-up tests were used to assess MEF. Multivariable linear regression analysis was used to evaluate the relationships between these fitness measures and lung function, adjusting for potential covariates. RESULTS: Enhanced CRF was associated with superior FEV1 and FVC after adjusting for covariates (ß=-.078, p=.015 for FEV1; ß=-.086, p=.009 for FVC). Push-ups were positively associated with FEV1 (ß=.102, p=.014), but not with FVC. In contrast, sit-ups showed no significant correlation with lung function in the fully adjusted model. CONCLUSION: The study demonstrated a clear association between improved physical fitness and better lung function in physically active young adults, with various exercises showing distinct associations with lung metrics. Notably, push-ups were particularly associated with higher FEV1. A future prospective study is necessary to determine whether routine exercises, such as push-ups, might lead to greater lung function.

Dupilumab 200 mg was efficacious in children (6-11 years) with moderate-to-severe asthma for up to 2 years: EXCURSION open-label extension study.

BACKGROUND: The phase 3 VOYAGE (NCT02948959) and open-label extension EXCURSION (NCT03560466) studies evaluated dupilumab in children (6-11 years) with uncontrolled moderate-to-severe asthma. This post hoc analysis assessed the efficacy and safety of add-on dupilumab 200 mg every 2 weeks (q2w), the largest dose cohort in both studies, in children from VOYAGE who participated in EXCURSION. METHODS: Annualized rate of severe asthma exacerbations (AERs), change in prebronchodilator percent predicted forced expiratory volume in 1 s (ppFEV1), and treatment-emergent adverse events were assessed in children with moderate-to-severe asthma who received dupilumab 200 mg q2w in VOYAGE and EXCURSION (dupilumab/dupilumab arm) and those who received placebo in VOYAGE and dupilumab 200 mg q2w in EXCURSION (placebo/dupilumab arm). These endpoints were also assessed in children with moderate-to-severe type 2 asthma (defined as blood eosinophil count ≥150 cells/µL or FeNO ≥20 ppb at the parent study baseline [PSBL]). RESULTS: In the overall population, dupilumab reduced AER and improved prebronchodilator ppFEV1 in the dupilumab/dupilumab arm (n = 158) for up to 2 years. Children receiving placebo/dupilumab (n = 85) showed similar reductions after initiation of dupilumab 200 mg q2w in EXCURSION. Similar results were observed for children with type 2 asthma at PSBL. The safety profile was consistent with the known safety profile of dupilumab. CONCLUSION: In children (6-11 years) with uncontrolled moderate-to-severe type 2 asthma, dupilumab 200 mg reduced exacerbation rates and improved lung function for up to 2 years and showed safety consistent with the known dupilumab safety profile.

The impact of inflammatory cells on lung function in asthmatics in a cross sectional retrospect study.

Background: Limited data exists on the impact of inflammatory cells and clinical characteristics on lung function in individuals with asthma. Objective: The objective is to examine the correlation between increased inflammatory cells, asthma symptoms, and lung function in patients with asthma in a clinical setting. Methods: A retrospective cohort study was conducted on 234 individuals suspected of having asthma in Xian, China between January 2008 and December 2021. Of those, 143 patients with complete clinical feature and lung function data were enrolled to examine the relationship between increased inflammatory cells, asthma symptoms, and lung function. Basic characteristics, blood eosinophil count, blood neutrophil count, blood platelet count, blood C-reactive protein (CRP), and comprehensive lung function analysis were evaluated at each inpatient for the 143 adult asthmatics. The association between inflammatory cells and clinical parameters with pulmonary function was compared. Results: The results of the study showed that individuals in the alcohol intake group had elevated blood eosinophil count compared to those in the non-alcohol intake group (P = 0.024). Long-acting inhaled beta 2 agonists and antibiotic therapy were associated with lower blood eosinophil count (P = 0.021 and P = 0.049, respectively) compared to other therapy. There was a independent association between blood eosinophil counts and FEV1 pre- and post-therapy in asthma but there was a markedly correlation between blood eosinophil counts and FEV1/FVC pre-and post-therapy in Asthma (P = 0.007). Blood neutrophil counts were inversely correlated with FEV1/FVC after treatment (P = 0.032). Night onset in asthma was positively correlated with blood neutrophil counts, while fever was negatively correlated with blood CRP (P = 0.028). Platelet counts >300 × 109/L after treatment were significantly associated with a decline in FEV (<0.001) in patients with asthma. Elevated blood eosinophil count was independently associated with clinical features in asthma. Conclusions: Based on the study's findings, there is a significant decline in FEV1/FVC among individuals with elevated blood eosinophil count, both pre- and post-bronchodilator while there was a independent relationship between blood eosinophil counts and FEV1 pre-and post-therapy in asthma. This suggests that increased levels of eosinophils may independently associated contribute to reduced lung function in asthma patients.

Hospital-Treated Infectious Diseases, Infection Burden, and Risk of Lung Cancer: An Observational and Mendelian Randomization Study.

BACKGROUND: Although infections play a role in the development of lung cancer, the longitudinal association between infection and the risk of lung cancer is disputed, and data relating to pathogen types and infection sites are sparse. RESEARCH QUESTION: How do infections affect subsequent lung cancer risk, and is the impact limited to specific microbes rather than infection burden? STUDY DESIGN AND METHODS: Data on > 900 infectious diseases were gathered from the UK Biobank study. Short- and long-term effects of infections were assessed by using time-varying Cox proportional hazards models. The analysis was repeated, excluding patients with concurrent multi-pathogen infections or outcomes within the 10 years following the initial hospitalization for the index infection. A life table approach was used to estimate years of life lost from lung cancer. Infection burden was defined as the sum of the number of infection episodes over time and co-occurring infections. The genome-wide association studies used in two-sample Mendelian randomization were obtained from mostly European ancestry. RESULTS: Hospital-treated infectious disease was associated with a greater risk of lung cancer (adjusted hazard ratio [aHR], 1.79; 95% CI, 1.74-1.83). aHRs for lung cancer ranged from 1.39 to 2.82 across pathogen types. The impact of lower respiratory tract infections (LRTIs) on lung cancer was the strongest, with an aHR of 3.22 (95% CI, 2.64-3.92); the aHR for extra-LRTIs was 1.29 (95% CI, 1.16-1.44). A dose-response association was observed between infection burden and lung cancer risk across different FEV1 percent predicted (Ptrend < .001). Multiple infections led to significant life lost from lung cancer at the age of 50 years. Mendelian randomization analysis reaffirmed the causal association. INTERPRETATION: Both observational and genetic analyses suggest that infectious diseases could increase the risk of lung cancer. The dual perspective on the LRTIs and extra-LRTIs impacts may inform lung cancer prevention strategies.

The predictive role of lung clearance index on FEV1 decline in cystic fibrosis.

BACKGROUND: The lung clearance index (LCI) is a sensitive lung function index that is used to detect early lung disease changes in children with cystic fibrosis (CF). This study aimed to define the predictive role of baseline LCI, along with other potential factors on the change in forced expiratory volume in one second (FEV1) during one-year follow-up in CF patients who had a percent predicted (pp) FEV1≥80. METHODS: LCI was concurrently performed on 57 CF patients who had ppFEV1 ≥80 at month zero. The ppFEV1 decline was evaluated prospectively during the one year follow up. The primary outcome of ppFEV1 decline in the study group in one year was dichotomized according to the median value for the decline in ppFEV1, which was 3.7. The LCI value predicting ppFEV1 decline at the end of one year was calculated with receiver operating characteristic curve analysis. Regression analysis was performed. Furthermore, a decision tree was constructed using classification and regression tree methods to better define the potential effect of confounders on the ppFEV1 decline. RESULTS: The LCI value for predicting ppFEV1 decline >3.7% at the end of one year was 8.2 (area under the curve: 0.80) Multivariable regression analysis showed that the absence of the F508del mutation in at least one allele, LCI >8.2 and initial FEV1 z-score were predictors of a ppFEV1 decline >3.7 (p<0.001). Factors altering ppFEV1 decline>3.7% at the end of one-year evaluated by decision trees were as follows: initial FEV1 z-score, type of CFTR mutation, LCI value and initial weight-for-age z-score. CONCLUSIONS: LCI is sensitive for predicting ppFEV1 decline in patients with ppFEV1 ≥80 along with the initial FEV1-z-score and type of CFTR mutation.

Longitudinal lung function trajectories in response to azithromycin therapy for chronic lung disease in children with HIV infection: a secondary analysis of the BREATHE trial.

BACKGROUND: Chronic lung disease (CLD) is common among children with HIV (CWH) including in those taking antiretroviral therapy (ART). Azithromycin has both antimicrobial and anti-inflammatory effects and has been effective in improving lung function in a variety of lung diseases. We investigated lung function trajectories among CWH with CLD on ART enrolled in a randomized controlled trial of adjuvant azithromycin. We also investigated factors that modified the effect of azithromycin on lung function. METHODS: The study used data from a double-blinded placebo-controlled trial conducted in Malawi and Zimbabwe of 48 weeks on azithromycin (BREATHE: ClinicalTrials.gov NCT02426112) among CWH aged 6 to 19 years taking ART for at least six months who had a forced expiratory volume in one second (FEV1) z-score <-1.0. Participants had a further follow-up period of 24 weeks after intervention cessation. FEV1, forced vital capacity (FVC) and FEV1/FVC were measured at baseline, 24, 48 and 72-weeks and z-scores values calculated. Generalized estimating equations (GEE) models were used to determine the mean effect of azithromycin on lung-function z-scores at each follow-up time point. RESULTS: Overall, 347 adolescents (51% male, median age 15 years) were randomized to azithromycin or placebo. The median duration on ART was 6.2 (interquartile range: 3.8-8.6) years and 56.2% had an HIV viral load < 1000copies/ml at baseline. At baseline, the mean FEV1 z-score was - 2.0 (0.7) with 44.7% (n = 155) having an FEV1 z-score <-2, and 10.1% had microbiological evidence of azithromycin resistance. In both trial arms, FEV1 and FVC z-scores improved by 24 weeks but appeared to decline thereafter. The adjusted overall mean difference in FEV1 z-score between the azithromycin and placebo arms was 0.004 [-0.08, 0.09] suggesting no azithromycin effect and this was similar for other lung function parameters. There was no evidence of interaction between azithromycin effect and baseline age, lung function, azithromycin resistance or HIV viral load. CONCLUSION: There was no observed azithromycin effect on lung function z-scores at any time point suggesting no therapeutic effect on lung function. TRIAL REGISTRATION: ClinicalTrials.gov NCT02426112. First registered on 24/04/2015.

The effect of Lactobacillus reuteri on pulmonary function test and growth of cystic fibrosis patients.

INTRODUCTION: Cystic fibrosis (CF) patients frequently experience gut microbiota dysbiosis. Probiotic supplementation is a potential therapeutic approach to modify gut microbiota and improve CF management through the gut-lung axis. The aim of this study was to investigate the effect of Lactobacillus reuteri supplementation on pulmonary function test, respiratory symptoms and growth in CF patients. METHODS: A randomized, placebo-controlled clinical trial was carried out on 40 children with CF aged from 6 to 20 years. Participants were designated to receive either L. reuteri or placebo daily for 4 months. Pulmonary function tests, weight, height and body mass index (BMI) z-scores were measured pre and post treatment. RESULTS: The median baseline BMI of the patients was 16.28 kg m-2. A significant change in the probiotic group's BMI z-score after the study period was observed (P = 0.034) but not for weight and height z-scores (P > 0.05). After treatment, Pseudomonas aeruginosa grew in sputum cultures of seven in the placebo and one patient in the intervention group (P = 0.03) while at baseline it grew in the sputum of four patients in each group. There was no significant difference in forced expiratory volume in the first second, forced expiratory flow at 25-75% or forced vital capacity change between the two groups after the treatment period (P > 0.05). Additionally, no significant differences were found in pulmonary exacerbations, hospitalization frequencies or COVID-19 infection between the two groups during the study (P > 0.05). CONCLUSION: The results suggest that L. reuteri supplementation may impact the growth of severely malnourished CF patients. Furthermore, it may be concluded that this strain might reduce P. aeruginosa in the sputum culture of CF patients. © 2024 Society of Chemical Industry.

5-HTP inhibits eosinophilia via intracellular endothelial 5-HTRs; SNPs in 5-HTRs associate with asthmatic lung function.

Background: Previous research showed that 5-hydroxytryptophan (5HTP), a metabolic precursor of serotonin, reduces allergic lung inflammation by inhibiting eosinophil migration across endothelial monolayers. Objective: It is unknown if serotonin receptors are involved in mediating this 5HTP function or if serotonin receptor (HTR) single nucleotide polymorphisms (SNPs) associate with lung function in humans. Methods: Serotonin receptor subtypes were assessed by qPCR, western blot, confocal microscopy, pharmacological inhibitors and siRNA knockdown. HTR SNPs were assessed in two cohorts. Results: Pharmacological inhibition or siRNA knockdown of the serotonin receptors HTR1A or HTR1B in endothelial cells abrogated the inhibitory effects of 5HTP on eosinophil transendothelial migration. In contrast, eosinophil transendothelial migration was not inhibited by siRNA knockdown of HTR1A or HTR1B in eosinophils. Surprisingly, these HTRs were intracellular in endothelial cells and an extracellular supplementation with serotonin did not inhibit eosinophil transendothelial migration. This is consistent with the inability of serotonin to cross membranes, the lack of selective serotonin reuptake receptors on endothelial cells, and the studies showing minimal impact of selective serotonin reuptake inhibitors on asthma. To extend our HTR studies to humans with asthma, we examined the CHIRAH and GALA cohorts for HTR SNPs that affect HTR function or are associated with behavior disorders. A polygenic index of SNPs in HTRs was associated with lower lung function in asthmatics. Conclusions: Serotonin receptors mediate 5HTP inhibition of transendothelial migration and HTR SNPs associate with lower lung function. These results may serve to aid in design of novel interventions for allergic inflammation.