Knocking Out Smoking and Pulmonary Hypertension with a K. Am J Respir Crit Care Med 2021;203:1216-1218. [PMID: 33357112 PMCID: PMC8456471 DOI: 10.1164/rccm.202011-4121ed]

Predictive Value of Smoking Index Combined with NT-proBNP for Patients with Pulmonary Hypertension Due to Chronic Lung Disease: A Retrospective Study

Purpose

Smoking is a major risk factor for the group 3 PH. NT-proBNP is a biomarker for risk stratification in PH. This study aims to investigate the effects of smoking status and smoking index (SI) on group 3 PH and to evaluate the value of SI and SI combined with NT-proBNP in early diagnosis and prediction of disease severity.

Patients and Methods

Four hundred patients with group 3 PH at the First Hospital of Shanxi Medical University between January 2020 and December 2021 were enrolled and divided into two groups: mild (30 mmHg ≤ pulmonary artery systolic pressure (PASP)≤50 mmHg) and non-mild (PASP >50 mmHg). The effect of smoking on group 3 PH was analyzed using univariate analysis, and logistic analysis was conducted to evaluate the risk of group 3 PH according to smoking status and SI. Spearman correlation coefficient was used to test the correlation between SI and the index of group 3 PH severity. The predictive value of SI was evaluated using a receiver operating characteristic (ROC) curve.

Results

Correlation and logistic analyses showed that SI was associated with PH severity. Smoking status (P=0.009) and SI (P=0.039) were independent risk factors for non-mild group 3 PH, and ROC showed that the predictive value of SI (AUC:0.596) for non-mild PH was better than that of the recognized pro-brain natriuretic peptide (NT-proBNP) (AUC:0.586). SI can be used as a single predictive marker. SI and NT-proBNP can be formulated as prediction models for screening non-mild clinical cases (AUC:0.628).

Conclusion

SI is a potentially ideal non-invasive predictive marker for group 3 PH. SI and NT-proBNP could be used to develop a prediction model for screening non-mild PH cases. This can greatly improve the predictive specificity of the established PH marker, NT-proBNP.

Pulmonary hypertension in adults completing tuberculosis treatment

Background

Pulmonary hypertension (PH) after tuberculosis (TB) is typically not included among the chronic lung diseases causing PH (group 3 PH), with few data available to support the inclusion.

Objectives

To determine the prevalence of PH in an adult population completing TB treatment.

Methods

This single-centre, cross-sectional study only included patients with their first documented episode of TB, and who were in the second half of treatment or had recently completed treatment. PH was assessed using transthoracic echocardiography. Questionnaires were completed, and spirometry and a 6-minute walk test were performed.

Results

One hundred patients were enrolled, with a mean age of 37.1 years, of whom 58% were male and 46% HIV positive. The median time since initiation of TB treatment was 22 weeks. The mean (standard deviation) measured right ventricular systolic pressure (RVSP) was 23.6 (6.24) mmHg. One participant had PH (defined as RVSP ≥40 mmHg; 95% confidence interval (CI) 0.0 - 3.0) and a further 3 had possible PH (RVSP ≥35 and <40 mmHg), with a combined PH prevalence of 4% (95% CI 0.2 - 7.8). Airflow obstruction on spirometry was found in 13.3% of 98 patients, while 25.5% had a reduced forced vital capacity. There was no association between RVSP or PH/possible PH and sex, age, HIV status, systemic hypertension, spirometry measurements or 6-minute walking distance. Smoking status was associated with RVSP, but not with the presence of PH/possible PH.

Conclusion

There was a significant prevalence of PH in this preliminary study of predominantly young patients completing treatment for a first episode of TB. Larger and more detailed studies are warranted.

Study synopsis

What the study adds. Of 100 adult patients with their first episode of tuberculosis (TB) who underwent echocardiograms near the end of treatment completion to determine the prevalence of pulmonary hypertension (PH), 1 (1%) had PH and a further 3 (3%) had possible PH. There was no association between sex, age, HIV status, lung function or 6-minute walking distance and the presence of PH. The study adds to the growing awareness of the association of TB with pulmonary vascular disease. It shows that even in a young population with a first episode of TB treated in an ambulatory setting, there is a significant prevalence of PH on treatment completion.Implications of the findings. Given that 10.6 million people acquire TB annually, the absolute global burden of cases with PH is likely to be high, but is underappreciated to date. Further work is urgently needed in this field.

Lung Microbiota and Metabolites Collectively Associate with Clinical Outcomes in Milder Stage Chronic Obstructive Pulmonary Disease

Rationale: Chronic obstructive pulmonary disease (COPD) is variable in its development. Lung microbiota and metabolites collectively may impact COPD pathophysiology, but relationships to clinical outcomes in milder disease are unclear. Objectives: Identify components of the lung microbiome and metabolome collectively associated with clinical markers in milder stage COPD. Methods: We analyzed paired microbiome and metabolomic data previously characterized from bronchoalveolar lavage fluid in 137 participants in the SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study), or (GOLD [Global Initiative for Chronic Obstructive Lung Disease Stage 0-2). Datasets used included 1) bacterial 16S rRNA gene sequencing; 2) untargeted metabolomics of the hydrophobic fraction, largely comprising lipids; and 3) targeted metabolomics for a panel of hydrophilic compounds previously implicated in mucoinflammation. We applied an integrative approach to select features and model 14 individual clinical variables representative of known associations with COPD trajectory (lung function, symptoms, and exacerbations). Measurements and Main Results: The majority of clinical measures associated with the lung microbiome and metabolome collectively in overall models (classification accuracies, >50%, P < 0.05 vs. chance). Lower lung function, COPD diagnosis, and greater symptoms associated positively with Streptococcus, Neisseria, and Veillonella, together with compounds from several classes (glycosphingolipids, glycerophospholipids, polyamines and xanthine, an adenosine metabolite). In contrast, several Prevotella members, together with adenosine, 5'-methylthioadenosine, sialic acid, tyrosine, and glutathione, associated with better lung function, absence of COPD, or less symptoms. Significant correlations were observed between specific metabolites and bacteria (Padj < 0.05). Conclusions: Components of the lung microbiome and metabolome in combination relate to outcome measures in milder COPD, highlighting their potential collaborative roles in disease pathogenesis.