Update in Chronic Obstructive Pulmonary Disease 2017

The Relationship between Serum Uric Acid Levels and Early Mortality in Chronic Obstructive Pulmonary Disease Cases during Exacerbation

AIM

In this study, it was aimed to compare the levels of serum uric acid and uric acid/creatinine ratios in patients with COPD during an attack or in stable COPD, and to show whether serum uric acid and uric acid/creatinine ratios are associated with early mortality in COPD patients during an acute attack.

MATERIALS AND METHODS

In this study, COPD acute attack (n=155) and stable COPD (n=30) patients were evaluated. The data of these patients were obtained from patient files and computer records. COPD diagnosis and severity assessment were made according to the GOLD 2006 guideline. Participants' age, gender, body mass index, pulmonary function test, arterial blood gas, uric acid, creatinine values and comorbidity information were recorded in the previously prepared Case Data Form. In 2012, when we conducted this study, gold 2006 was taken as the guideline for spirometry measurement, but spirometric measurements determined with reference values determined according to age, height and gender, and FEV1/FVC measurement <70% as diagnostic criteria in acute attack after bronchodilator were the guidelines used later, gold 2017. It is also compatible with gold2020 and gold2021 spirometry criteria.

RESULTS

It was determined that the uric acid (p<0.001) and uric acid/creatinine (p<0.001) levels of the patients in the acute attack group were significantly higher than the levels of the patients in the stable group. The attack group was divided into two subgroups according to certain cut-off points for uric acid (>6 mg/dl for women and >7 mg/dl for men) and uric acid/creatinine ratio (median value 7.10). Since the upper limit of the uric acid value measured in the blood is 6 mg/dl in women and 7-8 mg/dl in men, the cut-off points for uric acid (>6 mg/dl for women and >7 mg/dl for men) were determined in our study. According to this categorization, it was determined that there was no statistically significant relationship between uric acid level (odds ratio 2.985 [95% confidence interval 0.61814,151]) and early mortality risk.

CONCLUSION

The results of this study showed that the uric acid and uric acid/creatinine levels in the attack group were higher than the levels in the stable group, but these parameters were not associated with early mortality.

Correlation Between 2D Strain and Classic Echocardiographic Indices in the Diagnosis of Right Ventricular Dysfunction in COPD

Purpose

This study aims to define which of the right ventricular myocardial deformation indices best correlates with the classic echocardiographic measurements and indices of right ventricular (RV) dysfunction in patients with stable chronic obstructive pulmonary disease (COPD).

Patients and Methods

Ninety-one patients with stable COPD underwent clinical evaluation, spirometry, a 6-minute walk test, and echocardiographic examination. Patients were divided into two groups: “with RV dysfunction” (≥1 classic parameter) and “without RV dysfunction”. We used speckle tracking to estimate myocardial deformation. For all analyses, results were considered significant if p < 0.05.

Results

The mean age across all participants was 65 ± 9 years, with 53% (48/91) being male. Patients in the group with RV dysfunction were able to walk shorter distances and had higher estimated right ventricular systolic pressure (RVSP) and mean pulmonary arterial pressure (mPAP). The RV free wall longitudinal strain (RVFWLS) was the only deformation indices that showed a significant correlation with all classic measurements and indices in the diagnosis of RV dysfunction (Wald test, 10.24; p < 0.01; odds ratio, 1.61). In the ROC curve analysis, the absolute value <20% was the lowest cut-off point of this index for detection of RV dysfunction (AUC = 0.93, S: 95.8%, and E: 88%).

Conclusion

In COPD patients, RVFWLS is the myocardial deformation index that best correlates with classic echocardiographic parameters for the diagnosis of RV dysfunction using <20% as a cut-off point.

Omega-3 Fatty Acids and Genome-Wide Interaction Analyses Reveal DPP10-Pulmonary Function Association

RATIONALE

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have anti-inflammatory properties that could benefit adults with comprised pulmonary health.

OBJECTIVE

To investigate n-3 PUFA associations with spirometric measures of pulmonary function tests (PFTs) and determine underlying genetic susceptibility.

METHODS

Associations of n-3 PUFA biomarkers (α-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid [DPA], and docosahexaenoic acid [DHA]) were evaluated with PFTs (FEV1, FVC, and FEV1/FVC) in meta-analyses across seven cohorts from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium (N = 16,134 of European or African ancestry). PFT-associated n-3 PUFAs were carried forward to genome-wide interaction analyses in the four largest cohorts (N = 11,962) and replicated in one cohort (N = 1,687). Cohort-specific results were combined using joint 2 degree-of-freedom (2df) meta-analyses of SNP associations and their interactions with n-3 PUFAs.

RESULTS

DPA and DHA were positively associated with FEV1 and FVC (P < 0.025), with evidence for effect modification by smoking and by sex. Genome-wide analyses identified a novel association of rs11693320-an intronic DPP10 SNP-with FVC when incorporating an interaction with DHA, and the finding was replicated (P2df = 9.4 × 10-9 across discovery and replication cohorts). The rs11693320-A allele (frequency, ∼80%) was associated with lower FVC (PSNP = 2.1 × 10-9; βSNP = -161.0 ml), and the association was attenuated by higher DHA levels (PSNP×DHA interaction = 2.1 × 10-7; βSNP×DHA interaction = 36.2 ml).

CONCLUSIONS

We corroborated beneficial effects of n-3 PUFAs on pulmonary function. By modeling genome-wide n-3 PUFA interactions, we identified a novel DPP10 SNP association with FVC that was not detectable in much larger studies ignoring this interaction.

Gene silencing of receptor-interacting protein 2 protects against cigarette smoke-induced acute lung injury

BACKGROUND AND PURPOSE

Chronic obstructive pulmonary disease (COPD) is characterized by progressive alveolar damage and generally irreversible airflow limitation. Nuclear factor-κB (NF-κB) plays a critical role in COPD pathogenesis. Receptor-interacting protein 2 (Rip2), a 60 kDa adaptor protein, is a positive regulator of NF-κB pathway and also an inducible transcriptional product of NF-κB activation. We sought to investigate if Rip2 gene silencing could protect against cigarette smoke (CS)-induced acute lung injury.

EXPERIMENTAL APPROACH

Gene silencing efficacy of Rip2 siRNA was characterized in mouse macrophage and mouse lung epithelial cell lines, and in a CS-induced acute lung injury mouse model. Bronchoalveolar lavage (BAL) fluid cell counts, levels of pro-inflammatory and oxidative damage markers, lung section inflammatory and epithelium thickness scorings, and nuclear NF-κB translocation were measured.

KEY RESULTS

CS was found to upregulate Rip2 level in mouse lungs. Rip2 siRNA was able to suppress Rip2 levels in both macrophage and lung epithelial cell lines and in mouse lungs, block CS extract (CSE)-induced mediator release by the cultured cells, and abate neutrophil counts in BAL fluid from CS-challenged mice. Rip2 siRNA suppressed CS-induced inflammatory and oxidative damage markers, and nuclear p65 accumulation and transcriptional activation in lung tissues. Besides, Rip2 siRNA was able to disrupt CSE-induced NF-κB activation in a NF-κB reporter gene assay.

CONCLUSIONS AND IMPLICATIONS

Taken together, we report for the first time that Rip2 gene silencing ameliorated CS-induced acute lung injury probably via disruption of the NF-κB activity, postulating that Rip2 may be a novel therapeutic target for COPD.