Cardiovascular Studies in Patients with Chronic Obstructive Pulmonary Disease Due to Biomass Smoke or Tobacco

Endothelial function in patients with COPD: an updated systematic review of studies using flow-mediated dilatation

INTRODUCTION

Cardiovascular disease is a significant cause of morbidity and mortality in COPD. Endothelial dysfunction is suggested to be involved in cardiovascular disease pathogenesis, and multiple studies report endothelial dysfunction in COPD. This article summarized the current knowledge on endothelial function in COPD patients.

AREAS COVERED

Databases were screened until November 2022 for studies using ultrasound-based flow-mediated dilation in patients with stable COPD. Pooled effect sizes were calculated using random effects model. Meta-regression analyses assessed the effects of demographic and clinical variables.

EXPERT OPINION

34 studies were identified (1365 COPD patients; 617 controls). Pooled analysis demonstrated an impaired endothelial-dependent (-2.33%; 95%CI -3.30/-1.35; p < 0.001) and endothelial-independent dilation (-3.11%; 95%CI -5.14/-1.08; p = 0.003) in COPD patients when compared to non-COPD controls. Meta-regression identified that higher age, worse severity of airflow obstruction, and current smoking were significantly associated with impaired endothelial function. Studies evaluating the effects of pharmacological and non-pharmacological interventions on endothelial function in COPD patients demonstrated conflicting results.

Cardiovascular health impacts of wildfire smoke exposure

In recent years, wildland fires have occurred more frequently and with increased intensity in many fire-prone areas. In addition to the direct life and economic losses attributable to wildfires, the emitted smoke is a major contributor to ambient air pollution, leading to significant public health impacts. Wildfire smoke is a complex mixture of particulate matter (PM), gases such as carbon monoxide, nitrogen oxide, and volatile and semi-volatile organic compounds. PM from wildfire smoke has a high content of elemental carbon and organic carbon, with lesser amounts of metal compounds. Epidemiological studies have consistently found an association between exposure to wildfire smoke (typically monitored as the PM concentration) and increased respiratory morbidity and mortality. However, previous reviews of the health effects of wildfire smoke exposure have not established a conclusive link between wildfire smoke exposure and adverse cardiovascular effects. In this review, we systematically evaluate published epidemiological observations, controlled clinical exposure studies, and toxicological studies focusing on evidence of wildfire smoke exposure and cardiovascular effects, and identify knowledge gaps. Improving exposure assessment and identifying sensitive cardiovascular endpoints will serve to better understand the association between exposure to wildfire smoke and cardiovascular effects and the mechanisms involved. Similarly, filling the knowledge gaps identified in this review will better define adverse cardiovascular health effects of exposure to wildfire smoke, thus informing risk assessments and potentially leading to the development of targeted interventional strategies to mitigate the health impacts of wildfire smoke.

MMP-9-C1562T polymorphism and susceptibility to chronic obstructive pulmonary disease: A meta-analysis

BACKGROUND

To comprehensively evaluate the association between the polymorphism of matrix metalloproteinase-9 (MMP-9)-C1562T (rs3918242) and susceptibility to chronic obstructive pulmonary disease (COPD) in middle-aged and elderly patients through Meta-analysis.

METHODS

PubMed, EMBASE, CNKI, Wanfang, VIP, and other databases were searched by computer in the inception to August 2019 to collect all the case-control studies that met the inclusion criteria in this literature. Meta-analysis was performed using Stata 15.0, including the OR value calculations of the association between the merged MMP-9-C1562T polymorphism and the COPD susceptibility. Subgroup analysis, sensitivity analysis, and publication bias test were also performed. A total of 13 literature were included in this Meta-analysis with a total of 2512 cases and 2716 controls.

RESULTS

The results have shown that the OR of MMP-9-C1562T T allele to C allele was 0.35 (95% confidence interval [CI]: 0.23-0.52, P < .01). The subgroup analysis of ethnicity result showed that the merged OR of MMP-9-C1562T T allele to C allele was 0.24 (95% CI: 0.17-0.34, P < .01) in Caucasian while the merged OR was 0.62 (95% CI: 0.22-1.70, P > .05) in Asian. However, there were no statistically significant models in the dominant, recessive, homozygote and heterozygote genetic models.

CONCLUSION

The MMP-9-C1562T polymorphism was associated with the susceptibility to middle-aged and elderly COPD patients. Compared with T allele, C allele increased the risk of disease, especially in Caucasian, but not found in Asian.