The alterations of oral, airway and intestine microbiota in chronic obstructive pulmonary disease: a systematic review and meta-analysis.

Background: Increasing evidence indicates the microbial ecology of chronic obstructive pulmonary disease (COPD) is intricately associated with the disease's status and severity, and distinct microbial ecological variations exist between COPD and healthy control (HC). This systematic review and meta-analysis aimed to summarize microbial diversity indices and taxa relative abundance of oral, airway, and intestine microbiota of different stages of COPD and HC to make comparisons. Methods: A comprehensive systematic literature search was conducted in PubMed, Embase, the Web of Science, and the Cochrane Library databases to identify relevant English articles on the oral, airway, and intestine microbiota in COPD published between 2003 and 8 May 2023. Information on microbial diversity indices and taxa relative abundance of oral, airway, and intestine microbiota was collected for comparison between different stages of COPD and HC. Results: A total of 20 studies were included in this review, involving a total of 337 HC participants, 511 COPD patients, and 154 AECOPD patients. We observed that no significant differences in alpha diversity between the participant groups, but beta diversity was significantly different in half of the included studies. Compared to HC, Prevotella, Streptococcus, Actinomyces, and Veillonella of oral microbiota in SCOPD were reduced at the genus level. Most studies supported that Haemophilus, Lactobacillus, and Pseudomonas were increased, but Veillonella, Prevotella, Actinomyces, Porphyromonas, and Atopobium were decreased at the genus level in the airway microbiota of SCOPD. However, the abundance of Haemophilus, Lactobacillus and Pseudomonas genera exhibited an increase, whereas Actinomyces and Porphyromonas showed a decrease in the airway microbiota of AECOPD compared to HC. And Lachnospira of intestine microbiota in SCOPD was reduced at the genus level. Conclusion: The majority of published research findings supported that COPD exhibited decreased alpha diversity compared to HC. However, our meta-analysis does not confirm it. In order to further investigate the characteristics and mechanisms of microbiome in the oral-airway- intestine axis of COPD patients, larger-scale and more rigorous studies are needed. Systematic review registration: PROSPERO (https://www.crd.york.ac.uk/prospero/), identifier CRD42023418726.

Effect of Singing on Symptoms in Stable COPD: A Systematic Review and Meta-Analysis.

Background: Chronic obstructive pulmonary disease (COPD) is a chronic lung disease which feature is progressive airflow obstruction. Singing is a popular and convenient activity that requires people to manage their lung volumes and airflow actively. Despite the well-known benefits of singing to healthy people, the specific effect still remains unclear. Objective: To investigate the mental and psychological benefits of singing in patients with stable COPD. Search Methods: We used Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines (PRISMA) on randomized controlled trials (RCTs) including singing exercise as the main intervention in stable COPD. We searched 8 electronic databases, including Web of Science, PubMed, Embase, Cochrane Library, Clinical Trials.gov, and the Physical Therapy Evidence Database (PEDro), CNKI, and Wanfang Database from inception until May 2022. The searching languages was English or Chinese. Data extraction using standardized templates was performed by two independent reviewers. The quality of the studies was assessed using the PEDro scale. Data synthesis was performed with Revman 5.4. The pooled effect sizes are reported by MD and 95% CI. Results: Five RCTs involving 333 patients with stable COPD were included in this meta-analysis. Singing was regarded as the main intervention in the experimental group. Meta-analysis revealed that singing improves quality of life on Short Form 36 physical component summary (SF-36 PCS) (MD = 12.63, 95% CI: 5.52 to 19.73, P < 0.01) and respiratory muscle in maximal expiratory pressure (PEmax) (MD = 14.30, 95% CI: 0.87 to 27.73, P = 0.04) in patients with COPD. However, it has limited effects on Short Form 36 mental component summary (SF-36 MCS), lung function, exercise capability, and adverse mental state. Conclusion: Based on results of the meta-analysis, singing could be used to improve quality of life (SF-36 PCS) and respiratory muscles (PEmax) in patients with COPD.