SARS-CoV-2 Vaccine Effectiveness in Hospitalized Patients: A Multicenter Test-Negative Case-Control Study.

BACKGROUND: Phase III clinical trials have documented the efficacy of the SARS-CoV-2 vaccines in preventing symptomatic COVID-19. Nonetheless, it is imperative to continue analyzing the clinical response to different vaccines in real-life studies. Our objective was to evaluate the effectiveness of five different vaccines in hospitalized patients with COVID-19 during the third COVID-19 outbreak in Mexico dominated by the Delta variant. METHODS: A test-negative case-control study was performed in nine tertiary-care hospitals for COVID-19. We estimated odds ratios (OR) adjusted by variables related a priori with the likelihood of SARS-CoV-2 infection and its severity. RESULTS: We studied 761 subjects, 371 cases, and 390 controls with a mean age of 53 years (SD, 17 years). Overall, 51% had a complete vaccination scheme, and an incomplete scheme (one dose from a scheme of two), 14%. After adjustment for age, gender, obesity, and diabetes mellitus, we found that the effectiveness of avoiding a SARS-CoV-2 infection when hospitalized with at least one vaccination dose was 71% (OR 0.29, 95% CI 0.19-0.45), that of an incomplete vaccination scheme, 67% (OR 0.33, 95% CI 0.18-0.62), and that of any complete vaccination scheme, 73% (OR 0.27, 95% CI 0.17-0.43). CONCLUSIONS: The SARS-CoV-2 vaccination program showed effectiveness in preventing SARS-CoV-2 infection in hospitalized patients during a Delta variant outbreak.

[Small airway: from definition to treatment]. / Vía aérea pequeña: de la definición al tratamiento.

The small airway, present since the origins of humanity and described barely a century ago, has recently been discovered as the anatomical site where inflammation begins in some obstructive lung diseases, such as asthma and Chronic Obstructive Pulmonary Disease (COPD), per se. Small airway dysfuction was identified in up to 91% of asthmatic patients and in a large proportion of COPD patients. In subjects without pathology, small airway represent 98.8% (approximately 4500 ml) of the total lung volume, contributing only between 10-25% of the total lung resistance; however, in subjects with obstruction, it can represent up to 90% of the total resistance. Despite this, its morphological and functional characteristics allow its dysfunction to remain undetected by conventional diagnostic methods, such as spirometry. Hence the importance of this review, which offers an overview of the tools available to assess small airway dysfunction and the possible therapies that act in this silent zone.

La vía aérea pequeña, presente desde los orígenes de la humanidad y descrita hace apenas un siglo, se ha descubierto recientemente como el sitio anatómico donde inicia la inflamación provocada por algunas enfermedades pulmonares obstructivas: asma y enfermedad pulmonar obstructiva crónica (EPOC), per se. Se ha identificado disfunción de la vía aérea pequeña en el 91% de los pacientes asmáticos y en una gran proporción de quienes padecen EPOC. En los pacientes sin enfermedad, la vía aérea pequeña representa el 98.8% (4500 mL) del volumen pulmonar total, y solo aporta del 10 al 25% de la resistencia pulmonar total; sin embargo, en sujetos con obstrucción puede suponer el 90% de la resistencia total. A pesar de esto, sus características morfológicas y funcionales permiten que la disfunción pase inadvertida por métodos diagnósticos convencionales, por ejemplo la espirometría. Con base en lo anterior, el objetivo de este estudio fue revisar el panorama general de los métodos disponibles para evaluar la vía aérea pequeña y los posibles tratamientos asociados con esta zona silente.

Addiction to Tobacco Smoking and Vaping.

The tobacco epidemic has been one of the biggest public health threats, and smoking is one of the world's largest preventable causes of premature death. An estimated 15.4% of all deaths in the world are attributable to tobacco smoking. The present review aims to describe addiction to tobacco smoking and vaping. Tobacco and vaping devices contain nicotine, a highly addictive drug, which explains why smoking is so prevalent and persistent. Electronic cigarettes are a group of novel nicotine or tobacco products that have rapidly gained popularity in recent years. Electronic cigarette devices allow for the use of other drugs, including THC, while the lax regulation may allow for the introduction of toxic compounds that can lead to acute or subacute toxicity, such as the e-cigarette- or vaping-associated lung injury that has been linked to vitamin E acetate. In addition, regular vapers and heated tobacco devices emit toxins, although at lower concentrations than burned tobacco. However, more and more side effects have been identified. No new effective treatment for nicotine addiction has been developed recently, despite its huge adverse impact on overall health and other outcomes. As for the primary line of medications, the last one started in 2006, the varenicline, demonstrating a low interest in developing new medications against smoking, an unacceptable state of affairs, given the huge impact of smoking on morbidity and mortality.

Trajectories of Spirometric Patterns, Obstructive and PRISm, in a Population-Based Cohort in Latin America.

Background: Preserved ratio impaired spirometry (PRISm) has been associated with adverse outcomes and increased transition to other spirometric categories over time. We aimed to examine its prevalence, trajectories over time, and outcomes in a population-based sample from Latin America. Methods: Data were obtained from two population-based surveys of adults from three cities in Latin America (PLATINO study), conducted on the same individuals 5-9 years after their baseline examination. We estimated the frequency of PRISm defined by FEV1/FVC≥0.70 with FEV1 <80%, describing their clinical characteristics, longitudinal transition trajectories over time, factors associated with the transition. Results: At baseline, 2942 participants completed post-bronchodilator spirometry, and 2026 at both evaluations. The prevalence of normal spirometry was 78%, GOLD-stage 1 10.6%, GOLD 2-4 6.5%, and PRISm was: 5.0% (95% CI 4.2-5.8). PRISm was associated with less schooling, more reports of physician-diagnosis of COPD, wheezing, dyspnea, missing days at work, having ≥2 exacerbations in the previous year but without accelerated lung function decline. Mortality risk was significantly higher in PRISm (HR 1.97, 95% CI 1.2-3.3) and COPD GOLD 1-4 categories (HR 1.79, 95% CI 1.3-2.4) compared with normal spirometry. PRISm at baseline most frequently transitioned to another category at follow-up (46.5%); 26.7% to normal spirometry and 19.8% to COPD. The best predictors of transition to COPD were closeness of FEV1/FVC to 0.70, older age, current smoking, and a longer FET in the second assessment. Conclusion: PRISm, is a heterogeneous and unstable condition prone to adverse outcomes that require adequate follow-up.

Addiction to Tobacco Smoking and Vaping

ABSTRACT The tobacco epidemic has been one of the biggest public health threats, and smoking is one of the world's largest preventable causes of premature death. An estimated 15.4% of all deaths in the world are attributable to tobacco smoking. The present review aims to describe addiction to tobacco smoking and vaping. Tobacco and vaping devices contain nicotine, a highly addictive drug, which explains why smoking is so prevalent and persistent. Electronic cigarettes are a group of novel nicotine or tobacco products that have rapidly gained popularity in recent years. Electronic cigarette devices allow for the use of other drugs, including THC, while the lax regulation may allow for the introduction of toxic compounds that can lead to acute or subacute toxicity, such as the e-cigarette- or vaping-associated lung injury that has been linked to vitamin E acetate. In addition, regular vapers and heated tobacco devices emit toxins, although at lower concentrations than burned tobacco. However, more and more side effects have been identified. No new effective treatment for nicotine addiction has been developed recently, despite its huge adverse impact on overall health and other outcomes. As for the primary line of medications, the last one started in 2006, the varenicline, demonstrating a low interest in developing new medications against smoking, an unacceptable state of affairs, given the huge impact of smoking on morbidity and mortality.

Respiratory diseases in Mexico: analysis from the Global Burden of Disease study 2021.

BACKGROUND: Respiratory diseases (RD) are often analyzed separately rather than collectively, possibly leading to an underestimation of their total burden. OBJECTIVE: To analyze the burden of RD in Mexico for population aged 20 or older from 1990 to 2021. MATERIAL AND METHODS: We present the burden of RD in Mexico based on estimates of the Global Burden of Disease study for mortality and disability-adjusted life years (DALYs), comprising counts, rates per 100,000, as well as age-standardized rates. RDs were categorized into three key groups: chronic respiratory diseases (CRD), respiratory infections (RI), and respiratory cancers. RESULTS: In 2021, among those aged 20+, RDs were responsible for 336,728 deaths, which accounts for 30.5% of total deaths -a nearly threefold increase since 2019, primarily due to the COVID-19 pandemic. CRDs contributed with 3.4% of total deaths; RIs, with 25.9%; and respiratory cancers, with 1.2%. CRDs showed a continuous rise in deaths, crude mortality, and DALY rates across genders, with no signs of leveling. RD burden varied widely across Mexican states. Age-standardized CRD mortality rates have generally declined since 1990, except for interstitial lung diseases, which have consistently increased. CONCLUSION: The significant burden of mortality and disability due to RDs in Mexico underscores the n|ecessity for enhanced prevention, research, and for addressing risk factors such as smoking and pollution. Ongoing healthcare training can help reduce RD burden.

ANTECEDENTES: Las enfermedades respiratorias (ER) se analizan individualmente, posiblemente con subestimación de su carga total. OBJETIVO: Analizar la carga de las ER en México para población de 20 años o más de 1990 a 2021. MATERIAL Y MÉTODOS: Se presenta la carga de ER en México a partir de estimaciones del estudio Global Burden of Disease en cuanto a mortalidad y años de vida saludable (AVISA) perdidos que comprenden recuentos, tasas por 100 000 y tasas estandarizadas por edad. Las ER se categorizaron en enfermedades respiratorias crónicas (ERC), infecciones respiratorias y cánceres respiratorios. RESULTADOS: En 2021, las ER causaron la muerte de 336 728 adultos mayores de 20 años, lo que representó 30.5 % del total de defunciones, incremento cercano al triple respecto a 2019, principalmente debido a COVID-19. Las ERC contribuyeron con 3.4 % del total de muertes, las infecciones respiratorias con 25.9 % y los cánceres respiratorios con 1.2 %. La mortalidad y AVISA perdidos por ERC se incrementaron persistentemente, con variaciones entre los estados. Las tasas de mortalidad ajustadas por edad de las ERC disminuyeron desde 1990, excepto las enfermedades pulmonares intersticiales, que se incrementaron constantemente. CONCLUSIÓN: Los significativos niveles de mortalidad y discapacidad debidos a enfermedades respiratorias en México exigen mejorar la prevención, investigación y abordar factores de riesgo como tabaquismo y contaminación, además de fomentar la capacitación médica continua.

Longitudinal Characterization of a Neutralizing and Total Antibody Response in Patients with Severe COVID-19 and Fatal Outcomes.

The host immune response to SARS-CoV-2 appears to play a critical role in disease pathogenesis and clinical manifestations in severe COVID-19 cases. Until now, the importance of developing a neutralizing antibody response in the acute phase and its relationship with progression to severe disease or fatal outcome among hospitalized patients remains unclear. In this study, we aim to characterize and compare longitudinally the primary humoral immune host response in the early stages of the disease, looking for an association between neutralization, antibody titers, infective viral lineage, and the clinical outcome in hospitalized and non-hospitalized patients. A total of 111 patients admitted at INER from November 2021 to June 2022 were included. We found that patients with negative or low neutralization showed a significant reduction in survival probability compared to patients with medium or high neutralization. We observed a significant decrease in the median of neutralization in patients infected with viral variants with changes in RBD of the spike protein. Our results suggest that developing an early and robust neutralizing response against SARS-CoV-2 may increase survival probability in critical patients.

Lung volumes measurement using novel pressure derived method in participants with obstructive, restrictive and healthy lungs.

Background.Lung volumes can be measured by body plethysmography (BP), by inert gas dilution during a single-breath or multiple breaths and by radiographic methods based on chest roentgenogram or CT scanning. Our objective was to analyze the concordance between several methods including a new pressure-derived method (PDM) in a variety of pulmonary conditions.Methods. We recruited four groups of adult volunteers at the chronic obstructive pulmonary disease and tobacco clinic of a respiratory referral hospital: patients with lung bullae, with obstructive lung diseases, with restrictive lung diseases and healthy controls; all subjects underwent lung volume measurements according to ATS/ERS standards in random order with each method and then CT scanning. Differences among groups were estimated by Kruskal-Wallis tests. Concordance correlation coefficients (CCC) and Bland-Altman plots were performed.Results. Sixty-two patients were studied including 15 with lung bullae, 14 with obstructive lung diseases, 12 with restrictive lung disease and 21 healthy subjects. Highest concordance was obtained between BP and CT scanning (CCC 0.95, mean difference -0.35 l) and the lowest, with TLC-DLCOsb(CCC 0.65, difference -1.05 l). TLC measured by BP had a moderate concordance with the PDM (CCC = 0.91, mean difference -0.19 l). The PDM on the other hand had the lowest intra-test repeatability (2.7%) of all tested methods.Conclusions. Lung volumes measured by BP and CT had high concordance in the scenario of varied pulmonary conditions including lung bullae, restrictive and obstructive diseases. The new PDM device, had low intra-test variability, and was easy to perform, with a reasonable concordance with BP.

Air quality in Mexico City during the COVID-19 lockdown possibly decreased COPD exacerbations.

The reduction of air pollution during the #COVID19 lockdown in Mexico City possibly reduced the exacerbation rate in #COPD patients due to biomass and tobacco despite that the self-isolation was not as strict as expected. https://bit.ly/3Iyv98t.

Hydroxychloroquine for prophylaxis of COVID-19 in health workers: A randomized clinical trial.

INTRODUCTION: Health care workers are at high risk of being infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our aim is to evaluate the efficacy and safety of hydroxychloroquine (HCQ) for prophylaxis of coronavirus disease 19 (COVID-19) in health personnel exposed to patients infected by SARS-CoV-2. METHODS: Double-blind randomized, placebo-controlled single center clinical trial. Included subjects were health care workers caring for severe COVID-19 patients. Main outcome was time to symptomatic SARS-CoV-2 infection. RESULTS: 127 subjects with a confirmed baseline negative RT-PCR SARS-CoV2 test were included in the trial. 62 assigned to HCQ and 65 to placebo. One subject (1.6%) in the HCQ group and 6 (9.2%) subjects in the placebo group developed COVID-19 (Log-Rank test p = 0.07). No severe COVID-19 cases were observed. The study was suspended because of a refusal to participate and losses to follow up after several trials reported lack of effectiveness of hydroxychloroquine in hospitalized patients with COVID-19. CONCLUSION: The effect size of hydroxychloroquine was higher than placebo for COVID-19 symptomatic infection in health personnel, although this was not statistically significant. The trial is underpowered due to the failure to complete the estimated sample size.

Evaluation of Panbio rapid antigen test for SARS-CoV-2 in symptomatic patients and their contacts: a multicenter study.

BACKGROUND: Point-of-care rapid tests to identify SARS-CoV-2 can have clinical benefits. METHODS: A cross-sectional study in adults visiting emergency services or screening sites of referral hospitals for COVID-19 to validate the diagnostic performance of a rapid antigen test for SARS-CoV-2 (Abbott's Panbio) compared with reverse transcription-polymerase chain reaction (RT-PCR) testing. Tests were performed by health personnel in a routine situation during a COVID-19 outbreak. RESULTS: A total of 1060 participants (mean age 47, 46% with a self-reported comorbidity) were recruited from 8 hospitals in Mexico. Participants provided 1060 valid Panbio rapid test-RT-PCR test pairs with 45% testing positive in the RT-PCR. Overall sensitivity of the Panbio test was 54.2% (95% CI 51%-57%), and 69.1% (95% CI 66%-73%) for patients during the first week of symptoms. Sensitivity depended on viral load (cycle threshold (Ct) of RT-PCR) and days of symptoms. With a Ct ≤25, sensitivity was 82% (95% CI, 76%-87%). Specificity of the Panbio test was >97.8% in all groups. CONCLUSIONS: The Panbio rapid antigen test for SARS-CoV-2 had good specificity but low sensitivity. A negative test requires confirmation with RT-PCR, especially for testing after the first week of symptoms.

Hydroxychloroquine for the treatment of severe respiratory infection by COVID-19: A randomized controlled trial.

INTRODUCTION: The novel coronavirus pandemic (COVID-19) represents a major public health problem and it is key to find a treatment that reduces mortality. Our objective was to estimate whether treatment with 400 mg/day of Hydroxychloroquine for 10 days reduces in-hospital mortality in subjects with severe respiratory disease due to COVID-19 compared with placebo. MATERIAL AND METHODS: A double-blind, randomized, placebo-controlled trial to evaluate the safety and efficacy of Hydroxychloroquine for the treatment of severe disease by COVID-19 through an intention-to-treat analysis. Eligible for the study were adults aged more than 18 years with COVID-19 confirmed by RT-PCR and lung injury requiring hospitalization with or without mechanical ventilation. Primary outcome was 30-day mortality. Secondary outcomes: days of mechanical ventilation, days of hospitalization and cumulative incidence of serious adverse events. RESULTS: A total of 214 patients with COVID-19 were recruited, randomized and analyzed. They were hypoxemic with a mean SpO2 of 65% ± 20, tachycardic (pulse rate 108±17 min-1) and tachypneic (32 ±10 min-1); 162 were under mechanical ventilation at randomization. Thirty-day mortality was similar in both groups (38% in Hydroxychloroquine vs. 41% in placebo, hazard ratio [HR] 0.88, 95% Confidence Interval [95%CI] 0.51-1.53). In the surviving participants, no significant difference was found in secondary outcomes. CONCLUSION: No beneficial effect or significant harm could be demonstrated in our randomized controlled trial including 214 patients, using relatively low doses of Hydroxychloroquine compared with placebo in hospitalized patients with severe COVID-19.

Clinical Markers of Chronic Hypoxemia in Respiratory Patients Residing at Moderate Altitude.

Supplemental oxygen (SO) increases survival in hypoxemic patients. In hypoxia, mammals respond by modulating O2-sensitive transducers that stabilize the transcription factor hypoxia-inducible factor-1-alpha (HIF-1α), which transactivates the genes that govern angiogenesis and metabolic pathways. Residing at high altitudes exposes millions of people to hypoxemia with potential adverse consequences on their health. We aimed to identify markers of hypoxemia that can be used in the evaluation of patients in addition to pulse oximetry and arterial blood gases, especially those that could respond after 1 month of oxygen use. We performed a prospective pilot study at 2240 m above sea level, with repeated measurements before and after (b/a) 1-month home oxygen therapy in 70 patients with lung diseases, of which 24/20 have COPD, 41/39 obstructive sleep apnea (OSA), and 5/2 with interstitial lung diseases (ILD), all of them having chronic hypoxemia, as well as 70 healthy subjects as controls. Proteins evaluated included HIF-1α, vascular endothelial growth factor (VEGF), and erythropoietin (EPO). Among the main results, we found that hypoxemic patients had normal levels of HIF-1α but increased EPO compared with healthy controls. VEGF levels were heterogeneous in the sample studied, similar to the control group in COPD, slightly increased in OSA, and decreased in fibrosis. With oxygen treatment, the HIF-1α and EPO decreased in COPD and OSA but not in fibrosis, and VEGF remained constant over time. In conclusion, erythropoietin and HIF-1α identified hypoxemia initially and responded to oxygen. In pulmonary fibrosis, HIF-1α, EPO, and VEGF increased with oxygen therapy, which is likely linked to the disease's pathogenesis and clinical course rather than hypoxemia.

Associated risks of smoking and possible benefits of cessation in Covid-19: a rapid narrative review.

OBJECTIVE: To describe the possible risks associated to smoking in the spread and complications of Covid-19, em-phasizing in the benefits of quitting smoking. MATERIALS AND METHODS: The narrative review methodology and the established process for Cochrane rapid reviews were used. RESULTS: The scientific evidence related to smoking and Covid-19 remains limited. However, there is an already documented trend in cross-sectional, clinical studies and meta-analyses on the increased risk of adverse outcomes with Covid-19 associated with tobacco use. CONCLUSIONS: It is necessary to issue a warning that persons who smoke would have greater risks in the Covid-19 pandemic, which add to the many already known risks of tobacco use. Thus, quitting smoking becomes a relevant preventive measure to better confront SARS-CoV-2.

Associated risks of smoking and possible benefits of cessation in Covid-19: a rapid narrative review / Riesgos asociados con tabaquismo y posibles beneficios de cesación en Covid-19: una revisión narrativa rápida

Abstract: Objective: To describe the possible risks associated to smoking in the spread and complications of Covid-19, emphasizing in the benefits of quitting smoking. Materials and methods: The narrative review methodology and the established process for Cochrane rapid reviews were used. Results: The scientific evidence related to smoking and Covid-19 remains limited. However, there is an already documented trend in cross-sectional, clinical studies and meta-analyses on the increased risk of adverse outcomes with Covid-19 associated with tobacco use. Conclusions: It is necessary to issue a warning that persons who smoke would have greater risks in the Covid-19 pandemic, which add to the many already known risks of tobacco use. Thus, quitting smoking becomes a relevant preventive measure to better confront SARS-CoV-2.

Resumen: Objetivo: Describir los posibles riesgos asociados de tabaquismo con contagio y complicaciones por Covid-19, haciendo hincapié en los beneficios de dejar de fumar. Material y métodos: Se utilizó la metodología de revisión narrativa y el proceso establecido para las revisiones rápidas Cochrane. Resultados: La evidencia científica relacionada con el tabaquismo y Covid-19 todavía es limitada. Existe una tendencia ya documentada en estudios clínicos transversales y metaanálisis del aumento del riesgo de resultados adversos para Covid-19 asociados con el consumo de tabaco. Conclusiones: Es necesario advertir que las personas que fuman tendrán mayores riesgos en la pandemia de Covid-19, los cuales se suman a los muchos ya conocidos del consumo de tabaco, de modo que dejar de fumar se convierte en una medida preventiva relevante para enfrentar mejor el SARS-CoV-2.

Screening tool for restrictive and obstructive ventilatory abnormalities in a population-based survey

Abstract Background: A 6 s spirometry with an inexpensive pocket spirometer efficiently selects individuals for a diagnostic-quality spirometry for airflow limitation, but could also be useful to identify individuals with a restrictive pattern. Objectives: We evaluated an inexpensive simplified spirometer (chronic obstructive pulmonary disease [COPD]-6) as a screening tool to identify spirometric abnormalities. Methods: A population-based survey in Mexico City, with 742 participants performing pre- and post-BD spirometry and a three-maneuver 6 s spirometry (pre-BD) with a COPD-6. We evaluated forced expiratory volume in 1 s (FEV1), FEV6, and FEV1/FEV6 from the COPD-6, crude and expressed as the percentage of predicted (%P), to discriminate post-bronchodilator airflow obstruction (FEV1/forced vital capacity [FVC] <5th percentile) or restriction (FVC or FEV1 <5th percentile with normal FEV1/FVC) through receiver operating characteristics and their area under the curve (AUC). Results: FEV1%P was the best predictor to identify pre- and post-BD ventilatory abnormalities (best cutoff point 87%P, AUC 92% for restrictive pattern, 89% for obstructive pattern, and 91% for any spirometric abnormality). Deriving to clinical spirometry only those with <87%P (26% of the sample) missed only 12% of spirometric abnormalities most of the latter mild. Conclusions: An FEV1 <87%P from a pre-BD 6 s spirometry correctly identified individuals with spirometric ventilatory defects, either obstructive or restrictive.

Screening Tool for Restrictive and Obstructive Ventilatory Abnormalities in a Population-Based Survey.

BACKGROUND: A 6 s spirometry with an inexpensive pocket spirometer efficiently selects individuals for a diagnostic-quality spirometry for airflow limitation, but could also be useful to identify individuals with a restrictive pattern. OBJECTIVES: We evaluated an inexpensive simplified spirometer (chronic obstructive pulmonary disease [COPD]-6) as a screening tool to identify spirometric abnormalities. METHODS: A population-based survey in Mexico City, with 742 participants performing pre- and post-BD spirometry and a three-maneuver 6 s spirometry (pre-BD) with a COPD-6. We evaluated forced expiratory volume in 1 s (FEV1), FEV6, and FEV1/FEV6 from the COPD-6, crude and expressed as the percentage of predicted (%P), to discriminate post-bronchodilator airflow obstruction (FEV1/forced vital capacity [FVC] < 5th percentile) or restriction (FVC or FEV1 <5th percentile with normal FEV1/FVC) through receiver operating characteristics and their area under the curve (AUC). RESULTS: FEV1%P was the best predictor to identify pre- and post-BD ventilatory abnormalities (best cutoff point 87%P, AUC 92% for restrictive pattern, 89% for obstructive pattern, and 91% for any spirometric abnormality). Deriving to clinical spirometry only those with < 87%P (26% of the sample) missed only 12% of spirometric abnormalities most of the latter mild. CONCLUSIONS: An FEV1 < 87%P from a pre-BD 6 s spirometry correctly identified individuals with spirometric ventilatory defects, either obstructive or restrictive.

Identification of breath-prints for the COPD detection associated with smoking and household air pollution by electronic nose.

PURPOSE: The analysis of breath-print, has been proposed as an attractive alternative to investigate possible biomarkers of Chronic Obstructive Pulmonary Disease (COPD). The aim of the present study was to discriminate between healthy subjects, patients with COPD associated with smoking (COPD-S) and patients with COPD associated with household air pollution (COPD-HAP). METHODS: A cross-sectional study of 294 participants was conducted, 88 with smoking associated COPD, 28 associated with HAP and 178 healthy subjects. Breath-print analysis was performed by using the Cyranose 320 electronic nose. Group data were evaluated by Principal Component Analysis (PCA), Canonical Discriminant Analysis (CDA) and Support Vector Machine (SVM) and the test's diagnostic power by means of ROC (Receiver Operating Characteristic) curves. RESULTS: The results indicated that the breath-print of patients with COPD is different from the one of healthy subjects explaining a variability of 93.8% with a correct prediction of 97.8% and correct classification of 100%,also positive and negative predictive value of 96.5 and 100% respectively. Furthermore, the breath-print of exhaled breath from patients with COPD-S and COPD-HAP does not present any difference. CONCLUSIONS: The breath-print of exhaled breath from patients with COPD-S and COPD-HAP does not present any difference, which demonstrates that the breath-print is related to the disease and not to causality. With these results, the analysis of the breath-print of COPD is proposed as an alternative for a screening method in future clinical applications.

RESPIRATORY IMPACT OF ELECTRONIC CIGARETTES AND "LOW-RISK" TOBACCO.

Electronic cigarettes, handheld devices that generate an aerosol that may contain nicotine by heating a solution or e-liquid, have been increasingly used especially in the young population. The aerosol's composition is determined by temperature, and by the substances contained in the heated liquid: glycerin, propylene glycol, nicotine in variable concentrations, flavoring agents, and other non-nicotine compounds. >80 compounds (including known toxics, e.g., formaldehyde, acetaldehyde, metallic nanoparticles, and acrolein) have been found in e-liquid and aerosols. Airway irritation, mucus hypersecretion, and inflammatory response, including systemic changes, have been observed after the exposure to e-cigarettes, leading to an increase in respiratory symptoms and changes in respiratory function and the host defense mechanisms. E-cigarette has been linked with an increase of symptoms in individuals with asthma, cystic fibrosis, and chronic obstructive pulmonary disease. One of the major concerns in public health is the rise in e-cigarette experimentation among never-smokers, especially children and adolescents, which leads to nicotine addiction and increases the chances of becoming with time a conventional smoker. There is an urgent need to regulate e-cigarettes and electronic nicotine delivery systems, at least with the same restrictions to those applied to tobacco products, and not to consider them as harmless products.