International journal of chronic obstructive pulmonary disease
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Int J Chron Obstruct Pulmon Dis · Jan 2017
Observational StudyImpact of exacerbations on respiratory system impedance measured by a forced oscillation technique in COPD: a prospective observational study.
Forced oscillation technique (FOT) has been reported to be useful in the evaluation and management of obstructive lung disease, including COPD. To date, no data are available concerning long-term changes in respiratory system impedance measured by FOT. Additionally, although exacerbations have been reported to be associated with excessive lung function decline in COPD, the impact of exacerbations on the results of FOT has not been demonstrated. The aim of this study was to investigate the longitudinal changes in respiratory system impedance and the influence of exacerbations thereon. ⋯ Exacerbations of COPD lead not only to a decline in lung function but also to an increase in respiratory system impedance.
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Int J Chron Obstruct Pulmon Dis · Jan 2017
Identification of subtypes in subjects with mild-to-moderate airflow limitation and its clinical and socioeconomic implications.
The purpose of this study was to identify subtypes in patients with mild-to-moderate airflow limitation and to appreciate their clinical and socioeconomic implications. ⋯ Clinical and epidemiological heterogeneities of subjects with mild-to-moderate airflow limitation and a different level of health care utilization by each subtype are shown. Identification of a subtype with high health care demand could be a priority for effective utilization of limited resources.
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Int J Chron Obstruct Pulmon Dis · Jan 2017
Pri-microRNA-124 rs531564 polymorphism minor allele increases the risk of pulmonary artery hypertension by abnormally enhancing proliferation of pulmonary artery smooth muscle cells.
MicroRNA-124 (miR-124) has been reported to be downregulated in the cells exposed to hypoxia, which was confirmed in our study. We then used online microRNA target prediction tools to identify GRB2, SMAD5, and JAG1 as the candidate target genes of miR-124, and we next validated GRB2 as a direct gene by using luciferase reporter system. We also established the regulatory relationship between miR-124 and GRB2 by showing the negative linear relationship between GRB2 and miR-124 expression. ⋯ Meanwhile, we also conducted real-time polymerase chain reaction and Western blot analysis to study the expression of GRB2 among different genotypes or pulmonary artery smooth muscle cells (PASMCs) treated with miR-124 mimics, GRB2 small interfering RNA, and miR-124 inhibitors, respectively, and found that introduction of miR-124 or GRB2 small interfering RNA could reduce the expression of GRB2 and inhibit the proliferation of PASMCs, while miR-124 upregulated the expression of GRB2 and promoted the proliferation of PASMCs. A total of 412 COPD patients with PAH (n=182) or without PAH (n=230) were recruited in this study, and more individuals carrying at least one minor allele of rs531564 were found in the COPD patients with PAH than in those without PAH (odds ratio: 0.61, 95% confidence interval: 0.41-0.91; P=0.166). In conclusion, the presence of rs531564 minor allele may increase the risk of PAH in COPD by reducing miR-124 expression, increasing GRB2 expression, and promoting the proliferation of PASMCs.
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Int J Chron Obstruct Pulmon Dis · Jan 2017
Expanding The INSPIRED COPD Outreach Program™ to the emergency department: a feasibility assessment.
The Halifax-based INSPIRED COPD Outreach Program™ is a facility-to-community home-based novel clinical initiative that through improved care transitions, self-management, and engagement in advance care planning has demonstrated a significant (60%-80%) reduction in health care utilization with substantial cost aversion. By assessing the feasibility of expanding INSPIRED into the emergency department (ED) we anticipated extending reach and potential for positive impact of INSPIRED to those with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) who avoid hospital admission. ⋯ INSPIRED-ED outcomes were generally positive, however referral and enrollment rates were lower than anticipated. Despite the potential of early self-management education, the ED may not be the ideal recruitment setting for home-based programs. Our findings underline the importance of conducting preliminary work to ascertain best settings for implementing new self-management education initiatives.
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Int J Chron Obstruct Pulmon Dis · Jan 2017
Alveolar-capillary reserve during exercise in patients with chronic obstructive pulmonary disease.
Factors limiting exercise in patients with COPD are complex. With evidence for accelerated pulmonary vascular aging, destruction of alveolar-capillary bed, and hypoxic pulmonary vasoconstriction, the ability to functionally expand surface area during exercise may become a primary limitation. ⋯ COPD patients who can expand gas exchange surface area as assessed with DLCO during exercise relative to pulmonary blood flow have a more preserved exercise capacity.