American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Sep 2022
Risks of Mortality and Airflow Limitation in Japanese with Preserved Ratio Impaired Spirometry.
Rationale: Several Western studies have reported that participants with preserved ratio impaired spirometry (PRISm) have higher risks of airflow limitation (AFL) and death. However, evidence in East Asian populations is limited. Objectives: To investigate the relationship between PRISm and the risks of death and incident AFL in a Japanese population. ⋯ When examining the prognosis of each baseline lung function category, participants with PRISm had higher risks of all-cause death (HR, 2.20; 95% confidence interval, 1.35-3.59) and cardiovascular death (HR, 4.07; 1.07-15.42) than those with normal spirometry after adjusting for confounders. Moreover, the multivariable-adjusted risk of incident AFL was greater in participants with PRISm than in those with normal spirometry (HR, 2.48; 1.83-3.36). Conclusions: PRISm was associated with higher risks of all-cause and cardiovascular death and a greater risk of the development of AFL in a Japanese community.
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Am. J. Respir. Crit. Care Med. · Sep 2022
Randomized Controlled Trial Multicenter StudyExacerbation Profile and Risk Factors in a T2-Low Severe Asthma Population.
Rationale: The past 25 years have seen huge progress in understanding of the pathobiology of type-2 (T2) asthma, identification of measurable biomarkers, and the emergence of novel monoclonal antibody treatments. Although present in a minority of patients with severe asthma, very little is known about the mechanisms underlying T2-low asthma, making it a significant unmet need in asthma research. Objectives: The objective of this study was to explore the differences between study exacerbators and nonexacerbators, to describe physiological changes at exacerbation in those who are T2HIGH and T2LOW at the time of exacerbation, and to evaluate the stability of inflammatory phenotypes when stable and at exacerbation. ⋯ T2LOW asthma was an unstable phenotype, suggesting that exacerbation phenotyping should occur at the time of exacerbation. The clinically significant exacerbations in participants without evidence of T2 biology at the time of exacerbation highlight the unmet and pressing need to further understand the mechanisms at play in non-T2 asthma. Clinical trial registered with www.clinicaltrials.gov (NCT02717689).
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Am. J. Respir. Crit. Care Med. · Sep 2022
Observational StudyReversible Airflow Obstruction Predicts Future COPD Development in the SPIROMICS Cohort.
Rationale: Chronic obstructive pulmonary disease (COPD) is defined by fixed spirometric ratio, FEV1/FVC < 0.70 after inhaled bronchodilators. However, the implications of variable obstruction (VO), in which the prebronchodilator FEV1/FVC ratio is less than 0.70 but increases to 0.70 or more after inhaled bronchodilators, have not been determined. Objectives: We explored differences in physiology, exacerbations, and health status in participants with VO compared with reference participants without obstruction. ⋯ Conclusions: Significant risk for future COPD development exists for those with pre- but not post-BD airflow obstruction. These findings support consideration of expanding spirometric criteria defining COPD to include pre-BD obstruction. Clinical trial registered with www.clinicaltrials.gov (NCT01969344).
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Am. J. Respir. Crit. Care Med. · Sep 2022
Macrophage-NLRP3 Activation Promotes Right Ventricle Failure in Pulmonary Arterial Hypertension.
Rationale: Pulmonary arterial hypertension (PAH) often results in death from right ventricular failure (RVF). NLRP3 (nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3)-macrophage activation may promote RVF in PAH. Objectives: Evaluating the contribution of the NLRP3 inflammasome in RV macrophages to PAH RVF. ⋯ Conclusions: NLRP3-macrophage activation occurs in the decompensated RV in preclinical PAH models and patients with PAH. Inhibiting GP130 or NLRP3 signaling improves RV function. The concept that PAH RVF results from RV inflammation rather than solely from elevated RV afterload suggests a new therapeutic paradigm.