Alejandra Ramírez-Venegas

Geographic differences in clinical characteristics and management of COPD: the EPOCA study

Aims Data on differences in clinical characteristics and management of COPD in different countries and settings are limited. We aimed to characterize the profile of patients with COPD in a number of countries and their treatment in order to evaluate adherence to recommendations of international guidelines. Method This was an observational, international, cross-sectional study on patients with physician-diagnosed COPD. Demographic and clinical characteristics, risk factors, and treatment were collected by their physician via an internet web-based questionnaire developed for the study. Results A total of 77 investigators from 17 countries provided data on 833 patients. The countries with the highest number of patients included were: Argentina (128), Ecuador (134), Spain (162), and Hong Kong (153). Overall, 79.3% were men and 81% former smokers, with a mean FEV1 = 42.7%, ranging from 34.3% in Hong Kong to 58.8% in Ecuador. Patients reported a mean of 1.6 exacerbations the previous year, with this frequency being significantly and negatively correlated with FEV1(%) (r = −0.256; p < 0.0001). Treatment with short-acting bronchodilators and theophyllines was more frequent in Ecuador and Hong Kong compared with Spain and Argentina, and in patients belonging to lower socioeconomic levels (p < 0.0001 for all comparisons). Inadequacy of treatment with inhaled corticosteroids and theophyllines was high, with significant differences among countries. Conclusions Differences in the clinical characteristics and management of COPD were significant across countries. Adherence to international guidelines appears to be low. Efforts should be made to disseminate and adapt guidelines to the socioeconomic reality of different settings.

Pandemic influenza A/H1N1 virus infection and TNF , LTA , IL1B , IL6 , IL8 , and CCL polymorphisms in Mexican population: a case–control study

BackgroundSome patients have a greater response to viral infection than do others having a similar level of viral replication. Hypercytokinemia is the principal immunopathological mechanism that contributes to a severer clinical course in cases of influenza A/H1N1. The benefit produced, or damage caused, by these cytokines in severe disease is not known. The genes that code for these molecules are polymorphic and certain alleles have been associated with susceptibility to various diseases. The objective of the present study was to determine whether there was an association between polymorphisms of TNF, LTA, IL1B, IL6, IL8, and CCL1 and the infection and severity of the illness caused by the pandemic A/H1N1 in Mexico in 2009.MethodsCase–control study. The cases were patients confirmed with real time PCR with infection by the A/H1N1 pandemic virus. The controls were patients with infection like to influenza and non-familial healthy contacts of the patients with influenza. Medical history and outcome of the disease was registered. The DNA samples were genotyped for polymorphisms TNF rs361525, rs1800629, and rs1800750; LTA rs909253; IL1B rs16944; IL6 rs1818879; IL8 rs4073; and CCL1 rs2282691. Odds ratio (OR) and the 95% confidence interval (95% CI) were calculated. The logistic regression model was adjusted by age and severity of the illness in cases.ResultsInfection with the pandemic A/H1N1 virus was associated with the following genotypes: TNF rs361525 AA, OR = 27.00; 95% CI = 3.07–1248.77); LTA rs909253 AG (OR = 4.33, 95% CI = 1.82–10.32); TNF rs1800750 AA (OR = 4.33, 95% CI = 1.48–12.64); additionally, LTA rs909253 AG showed a limited statistically significant association with mortality (p = 0.06, OR = 3.13). Carriers of the TNF rs1800629 GA genotype were associated with high levels of blood urea nitrogen (p = 0.05); those of the TNF rs1800750 AA genotype, with high levels of creatine phosphokinase (p=0.05). The IL1B rs16944 AA genotype was associated with an elevated number of leukocytes (p <0.001) and the IL8 rs4073 AA genotype, with a higher value for PaO2 mm Hg.ConclusionThe polymorphisms of genes involved in the inflammatory process contributed to the severity of the clinical behavior of infection by the pandemic influenza A/H1N1 virus.

Increased platelet and erythrocyte arginase activity in chronic obstructive pulmonary disease associated with tobacco or wood smoke exposure.

Background Chronic obstructive pulmonary disease (COPD) is an inflammatory disease that is characterized by a progressive and irreversible decline in lung function and is caused primarily by chronic exposure to tobacco and to wood smoke. It is linked to oxidative stress and to an up-regulation of airway arginases and is also associated with alterations in platelets and erythrocytes. In the present study, arginase activity was studied in platelets and erythrocytes of 2 groups of COPD patients: 31 tobacco ex-smokers and 27 patients who had been exposed to wood smoke. A total of 15 healthy controls were also included. Methods Plasma, platelets, and erythrocytes were obtained from the blood samples. Levels of the oxidative stress biomarkers, carbonyls and malondialdehyde, were measured in the plasma, and arginase activity was quantified in platelets and erythrocytes. Results In both groups of COPD patients, an increase in the oxidative stress biomarkers was found. Platelet arginase activity in both COPD groups was 2-fold higher than that in the control group. In the erythrocytes, the arginase activity increased 1.7-fold over the control only in the wood smoke-induced COPD group. Discussion and Conclusions These results suggest that the increase in arginase activity in platelets and erythrocytes participates in the alteration in nitric oxide metabolism in COPD patients and that there may be some differences between the tobacco smoke- and wood smoke-induced COPD.

TNF, IL6, and IL1B Polymorphisms Are Associated with Severe Influenza A (H1N1) Virus Infection in the Mexican Population

Background Hypercytokinemia is the main immunopathological mechanism contributing to a more severe clinical course in influenza A (H1N1) virus infections. Most patients infected with the influenza A (H1N1) pdm09 virus had increased systemic levels of pro-inflammatory cytokines; including interleukin IL-6, IL-8, and tumor necrosis factor-alpha (TNF-α). We propose that single-nucleotide polymorphisms (SNPs) in the promoter regions of pro-inflammatory genes are associated with the severity of influenza A (H1N1) pdm09 virus infection. Methods 145 patients with influenza A (H1N1) (pA/H1N1), 133 patients with influenza-like illness (ILI), and 360 asymptomatic healthy contacts (AHCs) were included. Eleven SNPs were genotyped in six genes (TNF, LT, IL1B, IL6, CCL1, and IL8) using real-time PCR; the ancestral genotype was used for comparison. Genotypes were correlated with 27 clinical severity variables. Ten cytokines (GM-CSF, TNF-α, IL-2, IL-1β, IL-6, IL-8, IFN-γ, IL-10, IL-5, and IL-4) were measured on a Luminex 100. Results The IL6 rs1818879 (GA) heterozygous genotype was associated with severe influenza A (H1N1) virus infection (odds ratio [OR] = 5.94, 95% confidence interval [CI] 3.05–11.56), and two IL1B SNPs, rs16944 AG and rs3136558 TC, were associated with a decreased risk of infection (OR = 0.52 and OR = 0.51, respectively). Genetic susceptibility was determined (pA/H1N1 vs. AHC): the LTA rs909253 TC heterozygous genotype conferred greater risk (OR = 1.9), and a similar association was observed with the IL1B rs3136558 CC genotype (OR = 1.89). Additionally, severely ill patients were compared with moderately ill patients. The TNF-238 GA genotype was associated with an increased risk of disease severity (OR = 16.06, p = 0.007). Compared with ILIs, patients with severe pA/H1N1 infections exhibited increased serum IL-5 (pu200a<0.001) and IL-6 (pu200a = u200a0.007) levels. Conclusions The TNF gene was associated with disease severity, whereas IL1B and IL6 SNPs were associated with influenza A (H1N1) virus infection.

Genetic polymorphisms in CYP2A6 are associated with a risk of cigarette smoking and predispose to smoking at younger ages

Nicotine is the main component of cigarettes that causes addiction, which is considered a complex disease, and genetic factors have been proposed to be involved in the development of addiction. The CYP2A6 gene encodes the main enzyme responsible for nicotine metabolism. Depending on the study population, different genetic variants of CYP2A6 associated with cigarette smoking have been described. Therefore, we evaluated the possible association between SNPs in CYP2A6 with cigarette smoking and nicotine addiction-related variables in Mexican mestizo smokers. We performed a genetic association study comparing light smokers (LS, n=349), heavy smokers (HS, n=351) and never-smokers (NS, n=394). SNPs rs1137115, rs4105144, rs1801272 and rs28399433 were genotyped in the CYP2A6 gene. We found that the A allele of rs1137115 (OR=1.41) in exon 1 of CYP2A6 and the T allele of rs4105144 (OR=1.32) in the 5 UTR of the gene are associated with the risk of cigarette smoking (p<0.05); rs1137115 affects the level of alternative splicing, resulting in a CYP2A6 isoform with low enzymatic activity, whereas rs4105144 is likely to be in a binding site for the transcription factor for glucocorticoids receptor (GR) and regulates the expression of CYP2A6. In addition, having a greater number of risk alleles (rs1137115 (A), rs4105144 (T) and rs28399433 (G)) is associated with a younger age at onset. The present study shows that in Mexican mestizos, the analyzed SNPs confer greater risk in terms of consumption and age of onset.

Polymorphisms in HTR2A and DRD4 Predispose to Smoking and Smoking Quantity.

Background Genes encoding the receptors involved in the dopaminergic and serotonergic pathways are potential candidates in the mechanisms of nicotine addiction. Aims To identify genetic variants in the promoter regions and exons of the DRD4 and HTR2A genes associated with tobacco smoking and the degree of nicotine addiction in Mexican mestizos. Methods The study included 438 non-smokers (NS) and 1,157 current smokers, ranked based on their consumption of cigarettes per day (cpd): 574 heavy smokers (HS, >20 cpd) and 583 light smokers (LS, 1–10 cpd). Genotyping was performed for 4 and 8 single nucleotide polymorphisms (SNPs) in the DRD4 and HTR2A genes, respectively. Results The C allele of rs1800955 in DRD4 was found to be associated with cigarette smoking in the HS vs. NS and LS vs. NS comparisons (p = 2.34E-03 and p = 1.13E-03, respectively); the association was maintained in the homozygous CC genotype (p = 5.00E-04 and p = 2.00E-04, respectively). The T allele of rs6313 in HTR2A was significantly associated with cigarette smoking and a greater degree of nicotine addiction (p = 4.77E-03, OR = 1.55); the association was maintained in the homozygous genotype (TT) (p = 4.90E-03, OR = 1.96). The A allele of rs6313 was associated with cigarette smoking in the HS vs. NS comparison (p = 1.53E-02, OR = 1.36); the risk was nearly doubled in the homozygous AA genotype (p = 1.30E-03, OR = 1.83) compared with the heterozygous GA genotype (OR = 1.38). Conclusions Among Mexican mestizos, the C allele of rs1800955 in the DRD4 gene and the A allele of rs6311 in the HTR2A gene are associated with cigarette smoking, whereas the T allele of rs6313 in HTR2A is associated with cigarette smoking and the degree of nicotine addiction.

Prevalence and impact of respiratory symptoms in a population of patients with COPD in Latin America: The LASSYC observational study

BACKGROUNDnTo analyse the relationship between symptoms at different times during the 24-hour day and outcomes in COPD.nnnMETHODSnObservational cross-sectional study in a patients from 7 Latin American countries. The frequency of symptoms in the morning, at night and during the day was explored by means of standardised and validated questionnaires, and the relationship between symptoms and exacerbations and quality of life were investigated.nnnRESULTSn734 patients (59.6% male, mean age 69.5 years, mean FEV1 50% predicted normal) were recruited. The most frequent symptoms during the day were dyspnea (75% of patients, of which 94% mild-moderate) and cough (72.2%, of which 93.4% mild-moderate). Highly symptomatic patients had a greater impairment in FEV1, more exacerbations and worse scores in COPD assessment test (CAT) and Body Mass Index, Obstruction, Dyspnoea and Exacerbations (BODEx) index (all pxa0<xa00.001). Morning symptoms were more frequent than night-time symptoms, particularly cough and dyspnoea (morning: 50.1% and 45.7%; night-time: 33.2% and 24.4%, respectively), and mostly rated as mild or moderate. Patients with morning or night-time symptoms presented with worse severity of daytime symptoms. There was a strong correlation between intensity of daytime with morning or night-time symptoms, as well as with CAT score (rxa0=xa00.715; pxa0<xa00.001), but a weak correlation with FEV1 (rxa0=xa0-0.205; pxa0<xa00.001).nnnCONCLUSIONnMorning symptoms were more frequent than night-time symptoms, and having either morning and/or night-time symptoms was associated with worse severity of daytime symptoms. Increased symptoms were strongly associated with worse quality of life and more frequent exacerbations, but weakly associated with airflow limitation.nnnCLINICAL TRIAL REGISTRATIONnNCT02789540.

Adherence to inhaled therapies of COPD patients from seven Latin American countries: The LASSYC study.

Background This study assessed the adherence profiles to inhaled therapies and the agreement between two patient self-report adherence methods in stable COPD lpatients from seven Latin American countries. Methods This observational, cross-sectional, multinational, multicenter study involved 795 COPD patients (post-bronchodilator forced expiratory volume in 1 second/forced vital capacity [FEV1/FVC] <0.70). Adherence to inhaled therapy was assessed using the specific Test of Adherence to Inhalers (10-item TAI) and the generic 8-item Morisky Medication Adherence Scale (MMAS-8) questionnaires. The percentage agreement and the kappa index were used to compare findings. Results 59.6% of patients were male (69.5±8.7 years); post-bronchodilator FEV1 percent predicted was 50.0±18.6%. Mean values for 10-item TAI and MMAS-8 questionnaires were 47.4±4.9 and 6.8±1.6, respectively. Based on the TAI questionnaire, 54.1% of patients had good, 26.5% intermediate, and 19.4% poor adherence. Using the MMAS-8 questionnaire, 51% had high, 29.1% medium, and 19.9% low adherence. According to both questionnaires, patients with poor adherence had lower smoking history, schooling but higher COPD Assessment Test score, exacerbations in the past-year and post-bronchodilator FEV1. The agreement between 10-item TAI and MMAS-8 questionnaires was moderate (Kappa index: 0.42; agreement: 64.7%). Conclusion Suboptimal adherence to medication was frequent in COPD patients from Latin America. Low adherence was associated with worse health status impairment and more exacerbations. There was inadequate agreement between the two questionnaires. Greater effort should be made to improve COPD patients’ adherence to treatment, and assessment of adherence with more specific instruments, such as the TAI questionnaire, would be more convenient in these patients. Clinical Trial Registration NCT02789540

TNF promoter polymorphisms are associated with genetic susceptibility in COPD secondary to tobacco smoking and biomass burning

Background Smoking and smoke from biomass burning (BB) are the main environmental risk factors for COPD. Clinical differences have been described between COPD related to smoking and related to wood smoke, but no studies have shown genetic differences between patients exposed to these two risk factors. Methods To investigate a possible association of tumor necrosis factor (TNF) promoter polymorphisms, we conducted a case–control study. A total of 1,322 subjects were included in four groups: patients with a diagnosis of COPD secondary to smoking (COPD-S, n=384), patients with COPD secondary to biomass burning (COPD-BB, n=168), smokers without COPD (SWOC, n=674), and biomass burning-exposed subjects (BBES n=96). Additionally, a group of 950 Mexican mestizos (MMs) was included as a population control. Three single nucleotide polymorphisms (SNPs) were selected in the TNF gene (rs1800629, rs361525, and rs1800750) and one SNP in the lymphotoxin alpha gene (rs909253). Results Statistically significant differences were found with genotype GA of the rs1800629: COPD-S vs SWOC, (p<0.001, odds ratio [OR] =2.55, 95% CI=1.53–4.27); COPD-S vs COPD-BB (p,0.01). When performing the comparison of the less severe (G1: I + II) and the more severe (G2: III + IV) levels, differences were identified in G1 (p<0.05, OR=1.94, 95% CI=1.04–3.63) and G2 (p<0.001, OR=3.68, 95% CI=1.94–3.07) compared with SWOC. Regarding genotype GA of rs361525, it has been associated when comparing COPD-BB vs BBES (p=0.0079, OR=5.99, 95% CI=1.38–53.98). Conclusion The heterozygous genotype GA of polymorphisms rs1800629 and rs361525 in the TNF promoter are associated with the risk of COPD.

Data on polymorphisms in CYP2A6 associated to risk and predispose to smoking related variables

This article contains data on the single nucleotide polymorphisms (SNPs) rs1137115, rs1801272 and rs28399433 rs4105144 in CYP2A6 associated to smoking related variables in Mexican Mestizo smokers (Pérez-Rubio et al., 2017) [1]. These SNPs were selected due to previous associations with other populations. Mexican Mestizo smokers were classified according their smoking pattern. A genetic association test was performed.