Twenty years of changes in the definition of early chronic obstructive pulmonary disease

Imbalanced and Unchecked: The Role of Metal Dyshomeostasis in Driving COPD Progression

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory condition characterized by persistent inflammation and oxidative stress, which ultimately leads to progressive restriction of airflow. Extensive research findings have cogently suggested that the dysregulation of essential transition metal ions, notably iron, copper, and zinc, stands as a critical nexus in the perpetuation of inflammatory processes and oxidative damage within the lungs of COPD patients. Unraveling the intricate interplay between metal homeostasis, oxidative stress, and inflammatory signaling is of paramount importance in unraveling the intricacies of COPD pathogenesis. This comprehensive review aims to examine the current literature on the sources, regulation, and mechanisms by which metal dyshomeostasis contributes to COPD progression. We specifically focus on iron, copper, and zinc, given their well-characterized roles in orchestrating cytokine production, immune cell function, antioxidant depletion, and matrix remodeling. Despite the limited number of clinical trials investigating metal modulation in COPD, the advent of emerging methodologies tailored to monitor metal fluxes and gauge responses to chelation and supplementation hold great promise in unlocking the potential of metal-based interventions. We conclude that targeted restoration of metal homeostasis represents a promising frontier for ameliorating pathological processes driving COPD progression.

Moderate-intensity physical activity reduces the role of serum PFAS on COPD: A cross-sectional analysis with NHANES data

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has emerged as a leading cause of chronic disease morbidity and mortality globally, posing a substantial public health challenge. Perfluoroalkyl substances (PFAS) are synthetic chemicals known for their high stability and durability. Research has examined their potential link to decreased lung function. Physical activity (PA) has been identified as one of the primary modalities of the non-pharmacological treatment of COPD.

METHODS

To investigate the relationship between PFAS and COPD, and whether physical activity could reduce the risk of COPD caused by PFAS exposure, we used data from the NHANES 2013-2018, a cross-sectional study. Logistic regression analysis was used to examine the associations between PFAS and COPD in adult populations, and their associations in different PA types.

RESULTS

We finally included 4857 participants in the analysis, and found that Sm-PFOS (OR: 1.250), PFOA (OR: 1.398) and n-PFOA (OR: 1.354) were closely related to COPD; After stratified by gender, age and smoking, the results showed that Sm-PFOA (OR: 1.312) was related to COPD in female adult, and PFOA (OR: 1.398) and n-PFOA (OR: 1.354) were associated with COPD in male adults; The associations of Sm-PFOS (OR: 1.280), PFOA (OR: 1.481) and n-PFOA (OR: 1.424)with COPD tended to be stronger and more consistent in over 50 years old adults; Sm-PFOS was related to COPD in current smoker (OR: 1.408), and PFOA was related to COPD in former smoker (OR: 1.487); Besides, in moderate-intensity PA group, there were no associations of Sm-PFOS, PFOA and n-PFOA with COPD stratified by gender, age and smoking.

CONCLUSION

PFAS exposure may increase the risk of developing COPD, but regular moderate-intensity physical activity can protect individuals from evolving to the disease. However, longitudinal studies are needed to support these preliminary findings.

Genetic Variations in the Antioxidant Genes and their Role in Modulating Susceptibility Towards Chronic Obstructive Pulmonary Disease in the North Indian population

BACKGROUND

Chronic Obstructive Pulmonary Disease (COPD) is a persistent inflammatory lung condition characterized by an obstruction in removing oxygen from the lungs. Oxidant and antioxidant imbalance have long been hallmarks of COPD development, where the amount of antioxidants produced is less than that of oxidants. Here, polymorphism in the antioxidant enzymes like Catalase, Superoxide dismutase and Glutathione peroxidase plays an essential role in regulating the levels of oxidants.

METHODS

1000 subjects, including 500 COPD cases and 500 controls, have been recruited and genotyped to assess the correlation between COPD and the particular SNPS of antioxidant genes. Logistic regression was used to compute odds ratios (ORs) and 95% confidence intervals (CIs) to assess the association between SNPs and COPD risk. The relationship between spirometry value and COPD for all SNPs has been analysed using Kruskal Wallis's. Haplotype analysis has also been performed. The effect of SNP interactions on COPD risk was assessed through the Multifactor Dimensionality Reduction (MDR) approach, a nonparametric test for overcoming some of the limitations of the logistic regression for detecting and characterizing SNP interactions.

RESULTS

Our findings indicated a strong association between COPD and the variations in the CAT rs7943316 (OR=0.61, Pc=0.0001), SOD2 rs4880 (OR=2.07, Pc=0.0006), and GPx rs1050450 (OR=0.60, Pc=0.0018). Furthermore, SOD2 rs4880 was associated with forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) of COPD patients. Our study found that the triple combination of SOD1 (rs2234694), SOD1 (rs36232792) and SOD2 (rs4880) was found to be elevating the risk of COPD (OR=2.83, Pc=0.006). SOD2 rs4880 and GPx rs1050450 are also linked to cough and mucus production. The Haplotype study reveals a substantial relationship between CAT (rs7943316 and rs1001179) and SOD (rs2234694 and rs4880), which increases the risk of COPD. The three-locus model (CAT rs794331, CAT rs1101179, and GPx rs1050450) was the most effective for COPD risk assessment based on the MDR findings, which were statistically significant (p<0.0001).

CONCLUSION

This study shows that rs7943316, rs4880, and rs1050450 are associated with the risk of COPD in the north Indian population and have the potential to enhance our knowledge of COPD at the molecular level, which in turn might pave the way for earlier detection, treatment, and preventive efforts.

Prevalence of nicotine dependence among smokers aged 40 years and older in China

Background

Nicotine dependence, also known as tobacco dependence, is a common chronic disease and a major risk factor for chronic respiratory diseases. The present study was designed to determine the prevalence of nicotine dependence and its changes among smokers aged 40 years and older in China, to analyze the characteristics of nicotine dependence among smokers, and to provide a reference for smoking cessation interventions.

Methods

The data were sourced from nationally representative large-sample surveys conducted during 2014-2015 and 2019-2020 in the Chinese population, covering 125 counties (districts) in 31 provinces, autonomous regions and municipalities. Variables related to smoking and nicotine dependence among residents ≥40 years old were collected in face-to-face interviews. A total of 20,062 and 18,975 daily smokers were included in the 2014-2015 and 2019-2020 surveys, respectively. The severity of nicotine dependence was evaluated according to the Fagerström Test for Nicotine Dependence and Heaviness of Smoking Index. The level and change in nicotine dependence among daily smokers aged ≥40 years were estimated using a complex weighted sampling design, and their influencing factors were analyzed.

Results

Levels of nicotine dependence among daily smokers aged ≥40 years in China could be divided into very low, low, medium, high, and very high, accounting for 31.1%, 27.9%, 13.4%, 20.5%, and 7.1% of the total, respectively. The average Fagerström Test for Nicotine Dependence score was 3.9 (95% confidence interval [CI]: 3.8-4.0), with the prevalence of medium-high nicotine dependence being 41.0% (95% CI: 39.0-42.9%) and that of high and very high nicotine dependence being 27.6% (95% CI: 26.0-29.3%), both of which were significantly higher in men than in women (both P < 0.001). Among daily smokers, those with a low education level, age at smoking initiation <18 years, and with smoking duration of ≥20 years had a higher degree of nicotine dependence. In terms of geographic region, the level of medium-high nicotine dependence in South China was higher than in other areas, and the decline in the prevalence of high nicotine dependence was the greatest in Northwest China (P < 0.001). The prevalence of medium-high and high and very high nicotine dependence was significantly higher in men with chronic respiratory symptoms, chronic obstructive pulmonary disease (COPD), and/or chronic respiratory diseases than in men without these conditions (all P < 0.05). The prevalence of high and very high nicotine dependence in women with chronic respiratory symptoms and chronic respiratory diseases was significantly higher than that in women without these conditions (both P < 0.05). Compared with that during 2014-2015, the prevalence of high nicotine dependence among daily smokers decreased during 2019-2020 by 4.5 percentage points in the total population (P < 0.001) and by 4.8 percentage points in men (P < 0.001), with no significant change seen in women (P > 0.05). Additionally, the prevalence of high nicotine dependence in men with chronic respiratory symptoms and COPD decreased by 6.7 and 4.7 percentage points, respectively (P < 0.05), but showed no significant change in women with these conditions (P > 0.05). Multivariate logistic regression analysis showed that the risk of medium-high nicotine dependence was higher among daily smokers who were male; 50-59 years old; unmarried/divorced/widowed/separated; engaged in agriculture, forestry, husbandry, fishery and water conservancy; had a low education level; started smoking before the age of 18 years; and smoked for more than 20 years.

Conclusions

The past few years have seen a slight decline in the prevalence of high (severe) nicotine dependence among smokers aged ≥40 years in China. However, 41.0% of daily smokers had medium-high nicotine dependence, and 27.6% had high or very high nicotine dependence, with notable differences in population and geographic distributions. Development of tailored interventions, optimization of smoking cessation service systems, and integration of smoking cessation into the management of chronic diseases will effectively reduce the burden of nicotine dependence in China.