Differences in Exercise Capacity, Ventilatory Efficiency, and Gas Exchange between Patients with Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension Residing at High Altitude.

Background: Cardiopulmonary exercise testing (CPET) assesses exercise capacity and causes of exercise limitation in patients with pulmonary hypertension (PH). At altitude, changes occur in the ventilatory pattern and a decrease in arterial oxygen pressure in healthy; these changes are increased in patients with cardiopulmonary disease. Our objective was to compare the response to exercise and gas exchange between patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) residing at the altitude of Bogotá (2640 m). Methods: All patients performed an incremental CPET with measurement of oxygen consumption ( VO 2 ), dead space (VD/VT), ventilatory equivalents (VE/ VCO 2 ), and alveolar-arterial oxygen gradient ( PA-aO 2 ). X 2 test and one-way analysis of variance were used for comparisons between PAH and CTEPH. Results: We included 53 patients, 29 with PAH, 24 with CTEPH, and 102 controls as a reference of the normal response to exercise at altitude. CTEPH patients had a higher New York Health Association (NYHA) functional class than PAH (p = 0.037). There were no differences between patients with PAH and CTEPH in hemodynamics and VO 2 % of predicted (67.8 ± 18.7 vs. 66.0 ± 19.8, p < 0.05), but those with CTEPH had higher dyspnea, VD/VT (0.36 ± 0.09 vs. 0.23 ± 0.9, p < 0.001), VE/ VCO 2 (45.8 ± 7.1 vs. 39.3 ± 5.6, p < 0.001), and PA-aO 2 (19.9 ± 7.6 vs. 13.5 ± 7.6, p < 0.001) than PAH patients. Conclusions: At altitude, patients with PH present severe alterations in gas exchange during exercise. There were no differences in exercise capacity between PAH and CTEPH, but patients with CTEPH had more dyspnea and greater alterations in gas exchange during exercise. CPET made it possible to identify alterations related to the pathophysiology of CTEPH that could explain the functional class and dyspnea in these patients.

Sputum Biomarkers in Wood and Tobacco Smoke Etiotypes of Chronic Obstructive Pulmonary Disease.

Introduction: There is a need to better understand the etiotypes of chronic obstructive pulmonary disease (COPD) beyond the tobacco-smoke (TS-COPD). Wood smoke COPD (WS-COPD) is characterized by greater airway compromise, milder emphysema, and slower rate of lung function decline than TS-COPD. However, it is unclear if these two etiotypes of COPD have differences in sputum biomarker concentrations. Objective was to compare sputum levels of selected sputum biomarkers between WS-COPD and TS-COPD, and healthy controls. Methods: Eighty-eight women (69±12 years) were recruited and classified into: WS-COPD (n=31), TS-COPD (n=29) and controls (n=28). Using ELISA, we determined induced sputum levels of metalloproteinase 9 (MMP-9), chemokine ligand 5 (CCL5), interleukin-8 (IL-8), chemokine ligand 16 (CCL16/HCC-4) and vascular endothelial growth factor (VEGF-1). Differences were analyzed by Kruskal-Wallis and Mann-Whitney-U tests and correlation between airflow limitation and biomarkers by Spearman's test. Results: At similar degree of airflow obstruction, anthropometrics and medications use, the level of sputum CCL5 was higher in TS-COPD than WS-COPD (p=0.03) without differences in MMP-9, IL-8, CCL16/HCC-4, and VEGF-1. Women with WS-COPD and TS-COPD showed significantly higher sputum levels of MMP-9, IL-8 and CCL5 compared with controls (p<0.001). FEV1% predicted correlated negatively with levels of MMP-9 (rho:-0.26; P=0.016), CCL5 (rho:-0.37; P=0.001), IL-8 (rho:-0.42; P<0.001) and VEGF (rho:-0.22; P=0.04). Conclusion: While sputum concentrations of MMP-9, IL-8, and CCL5 were higher in COPD women compared with controls, women with TS-COPD had higher levels of CCL5 compared with those with WS-COPD. Whether this finding relates to differences in pathobiological pathways remains to be determined.

Prevalence of genetic mutations in alpha-1 antitrypsin deficiency (aatd) in patients with chronic obstructive pulmonary disease in Colombia.

BACKGROUND: Alpha-1 antitrypsin deficiency (AATD) is an underrecognized genetic disorder associated mainly with pulmonary emphysema and Chronic Obstructive Pulmonary Disease (COPD). All individuals with COPD regardless of age or ethnicity should be tested for AATD, but in Colombia its prevalence in unknown. MAIN OBJECTIVE: To determine the prevalence of the genetic mutations, present in AATD in adult patients with COPD in Colombia, using a genotyping test on cells from the oral mucosa. METHODS: This was a multicentre, observational, cross-sectional study which included adult patients attending seven COPD care centres in Colombia. Demographic data, medical history, including history of exposure to smoking and biomass smoke, most recent spirometry, pharmacological and non-pharmacological treatment received, serum AAT levels, and mutations detected by the genotyping test were recorded for all the recruited patients. For the comparison of variables between the groups with and without mutation, we used the X2 test for the qualitative variables and the Student's t-test or Mann-Whitney U test according to their distribution. MAIN FINDINGS: We collected a sample of 1,107 patients, the median age was 73.8 years (87.6-79.9). Mutations were documented in 144 patients (13.01%), the majority had the M/S mutation (78.50%), followed by M/Z (9.72%). One patient had a ZZ mutation and two patients had null alleles. In total, 23 patients had mutations associated with serum AAT deficiency (levels below 60 mg/dl). CONCLUSIONS: Genetic mutations were documented in 13.01% of patients with COPD in Colombia and 2.07% were AATD-related, showing that there is a significant number of underdiagnosed patients.

Sex differences regarding the impact of a standardized adaptation session in Colombian patients with obstructive sleep apnea and poor adherence to positive airway pressure devices / Diferencias por sexo respecto al impacto de una sesión de adaptación en pacientes colombianos con apnea obstructiva del sueño y mala adherencia a dispositivos de presión positiva

Abstract Introduction: Positive airway pressure (PAP) is the most effective treatment for obstructive sleep apnea (OSA) but adherence to this device is poor. The Sleep and Breathing Disorders Clinic of Fundación Neumológica Colombiana (FNC) has a standardized adaptation session (SAS) aimed at patients with difficulties in using PAP devices. Objective: To evaluate the impact of a SAS in short-term adherence to PAP therapy in patients with OSA, and to determine differences by sex. Materials and methods: Before-and-after single cohort study conducted in 40 people aged >18 years with an apnea-hypopnea index >15/hour and treated at the FNC, Bogotá D.C. (Colombia) between 2015 and 2017, who attended a SAS due to poor adherence to PAP therapy (defined as <4 hours use in 70% of nights). Data on the hours of use of the PAP device and the percentage of days in which it was used >4 hours were recorded before and after the intervention to evaluate changes in patients' adherence. Descriptive statistics were used for data analysis. The paired samples t-test was used for the comparison of variables before and after the intervention. Results: A significant increase was observed in PAP device use (1.8 hours, 95%CI: 1.3-2.3; p<0.001) and in the percentage of days it was used >4 hours (35.6%, 95%CI: 26.0-45.3; p<0.001). Among men, the increase was higher in both cases (2.3 hours, 95%CI: 1.7-2.9; p=0.029 and 47.8%, 95%CI: 32.9-62.8; p=0.029). Conclusion: The SAS offered by the FNC, which includes education strategies and the identification and solving of barriers hindering the use of PAP devices, significantly increased the hours of PAP device use and the percentage of days in which it was used >4 hours in the study population, particularly in men.

Resumen Introducción. La terapia de presión positiva en la vía aérea (PAP) es el tratamiento más efectivo de la apnea obstructiva del sueño (AOS); sin embargo, la adherencia no es óptima. La clínica de trastornos respiratorios del sueño de la Fundación Neumológica Colombiana (FNC) tiene una sesión de adaptación estandarizada (SAE) dirigida a pacientes con dificultades en el uso de equipo PAP. Objetivo. Evaluar el impacto de una SAE en la adherencia a corto plazo a la terapia de PAP en pacientes con AOS y determinar diferencias por sexo. Materiales y métodos. Estudio de cohorte única de antes y después realizado en 40 pacientes >18 años con un índice de apnea-hipopnea >15/hora atendidos en la FNC, en Bogotá D.C., Colombia, entre 2015 y 2017 y que asistieron a una SAE debido a una pobre adherencia a la terapia de PAP (<4 horas de uso el 70% de las noches). Se registraron los datos de uso en horas del equipo de PAP y el porcentaje de días en que se usó más de 4 horas antes y después de la intervención. Los datos se analizaron mediante estadística descriptiva y se empleó la prueba T de muestras emparejadas para comparar las variables antes y después de la intervención. Resultados. Se observó un aumento significativo después de la SAE en las horas de uso del equipo de PAP (1.8 horas, IC95%: 1.3-2.3; p<0.001) y del porcentaje de días en que su uso fue >4 horas (35.6%, IC95%: 26.0-45.3; p<0.001); el incremento fue mayor en los hombres en ambos casos (2.3 horas, IC95%: 1.7-2.9; p=0.029, y 47.8%, IC95%: 32.9-62.8; p=0.029). Conclusión. La SAE que brinda la FNC, la cual incluye estrategias educativas y la identificación y solución de barreras que dificultan el uso del equipo de PAP, aumentó de forma significativa las horas de uso de los dispositivos de PAP y el porcentaje de días con uso >4 horas en la población de estudio, en particular en los hombres.

Effect of pulmonary hypertension on exercise capacity and gas exchange in patients with chronic obstructive pulmonary disease living at high altitude.

BACKGROUND: Pulmonary hypertension (PH) is associated with decreased exercise tolerance in chronic obstructive pulmonary disease (COPD) patients, but in the altitude the response to exercise in those patients is unknown. Our objective was to compare exercise capacity, gas exchange and ventilatory alterations between COPD patients with PH (COPD-PH) and without PH (COPD-nonPH) residents at high altitude (2640 m). METHODS: One hundred thirty-two COPD-nonPH, 82 COPD-PH, and 47 controls were included. Dyspnea by Borg scale, oxygen consumption (VO2), work rate (WR), ventilatory equivalents (VE/VCO2), dead space to tidal volume ratio (VD/VT), alveolar-arterial oxygen tension gradient (AaPO2), and arterial-end-tidal carbon dioxide pressure gradient (Pa-ETCO2) were measurement during a cardiopulmonary exercise test. For comparison of variables between groups, Kruskal-Wallis or one-way ANOVA tests were used, and stepwise regression analysis to test the association between PH and exercise capacity. RESULTS: All COPD patients had a lower exercise capacity and higher PaCO2, A-aPO2 and VD/VT than controls. The VO2 % predicted (61.3 ± 20.6 vs 75.3 ± 17.9; p < 0.001) and WR % predicted (65.3 ± 17.9 vs 75.3 ± 17.9; p < 0.001) were lower in COPD-PH than in COPD-nonPH. At peak exercise, dyspnea was higher in COPD-PH (p = 0.011). During exercise, in COPD-PH, the PaO2 was lower (p < 0.001), and AaPO2 (p < 0.001), Pa-ETCO2 (p = 0.033), VE/VCO2 (p = 0.019), and VD/VT (p = 0.007) were higher than in COPD-nonPH. In the multivariate analysis, PH was significantly associated with lower peak VO2 and WR (p < 0.001). CONCLUSION: In COPD patients residing at high altitude, the presence of PH was an independent factor related to the exercise capacity. Also, in COPD-PH patients there were more dyspnea and alterations in gas exchange during the exercise than in those without PH.

Impacto clínico de un grupo de discusión multidisciplinaria en el diagnóstico de fibrosis pulmonar idiopática en Colombia / Clinical impact of a multidisciplinary discussion group on the diagnosis of idiopathic pulmonary fibrosis in Colombia

Resumen Introducción: la fibrosis pulmonar idiopática (FPI) es una enfermedad pulmonar intersticial (EPID) de mal pronóstico, considerada huérfana en Colombia. Un diagnóstico correcto tiene implicaciones para el paciente y los costos de atención. Los grupos de discusión multidisciplinaria (GDM) se consideran el estándar de oro en el diagnóstico. No hay estudios previos en Colombia de la experiencia de un GDM. Objetivos: evaluar el impacto de un GDM en una institución de cuarto nivel en Bogotá en cambio de diagnóstico de pacientes con EPID y la concordancia entre el diagnóstico inicial y final de FPI. Material y métodos: pacientes con EPID evaluados entre 2015-2018 por el GDM conformado por neumólogos, radiólogo, patólogo y reumatólogos. Criterios ATS/ERS/JRS/ALAT de diagnóstico de FPI. Descripción del cambio en el diagnóstico y concordancia entre el diagnóstico inicial y del GDM en FPI. Resultados: de 165 pacientes con EPID se cambió el diagnóstico en 35.2%. En 77.3% pacientes con diagnóstico inicial de FPI y en 6.7% con diagnóstico inicial diferente a FPI el GDM confirmó FPI. Al descartar FPI, los principales diagnósticos fueron neumonitis de hipersensibilidad en fase crónica (29.4%) y neumonía intersticial no específica (23.5%). El índice kappa entre el diagnóstico inicial y final de FPI fue 0.71 (0.60-0.82). Conclusiones: el GDM en EPID tuvo un importante impacto clínico demostrado por un alto porcentaje de cambió del diagnóstico de remisión. Se descartó el diagnóstico inicial de FPI en un porcentaje significativo de pacientes y se ratificó en un grupo menor sin esta sospecha clínica inicial. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2017).

Abstract Introduction: idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease (ILD) with a poor prognosis, considered an orphan disease in Colombia. An accurate diagnosis has implications for the patient and healthcare costs. Multidisciplinary discussion groups (MDGs) are considered the gold standard for diagnosis. There are no prior studies in Colombia on the experience of an MDG. Objectives: to evaluate the impact of an MDG in a quaternary care institution in Bogotá on the change in the diagnosis of patients with ILD and the concordance between the initial and final diagnosis of IPF. Materials and methods: patents with ILD evaluated from 2015-2018 by the MDG made up of pulmonologists, a radiologist, a pathologist and rheumatologists. The ATS/ERS/JRS/ALAT diagnostic criteria for IPF. A description of changes in the diagnosis and the agreement between the initial diagnosis and the MDG diagnosis of IPF. Results: out of 165 patients with ILD, the diagnosis was changed in 32.5%. The MDG confirmed IPF in 77.3% of patients with an initial diagnosis of ILD and 6.7% of those with a different initial diagnosis. When IPF was ruled out, the main diagnoses were chronic hypersensitivity pneumonitis (24.8%) and nonspecific interstitial pneumonia (23.5%). The Kappa index between the initial and final IPF diagnoses was 0.71 (0.60-0.82). Conclusions: the MDG on ILD had a significant clinical impact evidenced by a high percentage of change in the referral diagnosis. The initial diagnosis of IPF was ruled out in a significant percentage of patients and confirmed in a smaller group which did not have this initial clinical suspicion. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2017).

Exercise Capacity, Ventilatory Response, and Gas Exchange in COPD Patients With Mild to Severe Obstruction Residing at High Altitude.

BACKGROUND: Exercise intolerance, desaturation, and dyspnea are common features in patients with chronic obstructive pulmonary disease (COPD). At altitude, the barometric pressure (BP) decreases, and therefore the inspired oxygen pressure and the partial pressure of arterial oxygen (PaO2) also decrease in healthy subjects and even more in patients with COPD. Most of the studies evaluating ventilation and arterial blood gas (ABG) during exercise in COPD patients have been conducted at sea level and in small populations of people ascending to high altitudes. Our objective was to compare exercise capacity, gas exchange, ventilatory alterations, and symptoms in COPD patients at the altitude of Bogotá (2,640 m), of all degrees of severity. METHODS: Measurement during a cardiopulmonary exercise test of oxygen consumption (VO2), minute ventilation (VE), tidal volume (VT), heart rate (HR), ventilatory equivalents of CO2 (VE/VCO2), inspiratory capacity (IC), end-tidal carbon dioxide tension (PETCO2), and ABG. For the comparison of the variables between the control subjects and the patients according to the GOLD stages, the non-parametric Kruskal-Wallis test or the one-way analysis of variance test was used. RESULTS: Eighty-one controls and 525 patients with COPD aged 67.5 ± 9.1 years were included. Compared with controls, COPD patients had lower VO2 and VE (p < 0.001) and higher VE/VCO2 (p = 0.001), A-aPO2, and V D /V T (p < 0.001). In COPD patients, PaO2 and saturation decreased, and delta IC (p = 0.004) and VT/IC increased (p = 0.002). These alterations were also seen in mild COPD and progressed with increasing severity of the obstruction. CONCLUSION: The main findings of this study in COPD patients residing at high altitude were a progressive decrease in exercise capacity, increased dyspnea, dynamic hyperinflation, restrictive mechanical constraints, and gas exchange abnormalities during exercise, across GOLD stages 1-4. In patients with mild COPD, there were also lower exercise capacity and gas exchange alterations, with significant differences from controls. Compared with studies at sea level, because of the lower inspired oxygen pressure and the compensatory increase in ventilation, hypoxemia at rest and during exercise was more severe; PaCO2 and PETCO2 were lower; and VE/VO2 was higher.

SMALLa AIRWAY DISEASE IN COPD ASSOCIATED TO BIOMASS EXPOSURE.

Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous entity that may result from different causative agents and risk factors and may follow diverse clinical courses, including COPD secondary to biomass smoke exposure. At present, this phenotype is becoming more important for two reasons: first, because at least almost half of the world's population is exposed to biomass smoke, and second, because the possibility of it being diagnosed is increasing. Biomass smoke exposure COPD affects primarily women and is related with insults to the airways occurred during early life. Although constituents of biomass smoke and tobacco smoke are similar, the physiopathological changes they induce differ depending not only on the chemical composition (related with the type of fuel used) but also on the particle size and the inhalation pattern. Evidence has shown that biomass smoke exposure affects the airway, predominantly the small airways causing anthracofibrosis and peribronchiolar fibrosis changes that will clinically translate into chronic bronchitis symptoms, with a high impact on the quality of life. In this review, we focus especially on the main epidemiological and clinical differences between COPD secondary to biomass exposure and COPD caused by tobacco exposure.

Small airway disease in COPD associated to biomass exposure

Abstract Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous entity that may result from different causative agents and risk factors and may follow diverse clinical courses, including COPD secondary to biomass smoke exposure. At present, this phenotype is becoming more important for two reasons: first, because at least almost half of the world’s population is exposed to biomass smoke, and second, because the possibility of it being diagnosed is increasing. Biomass smoke exposure COPD affects primarily women and is related with insults to the airways occurred during early life. Although constituents of biomass smoke and tobacco smoke are similar, the physiopathological changes they induce differ depending not only on the chemical composition (related with the type of fuel used) but also on the particle size and the inhalation pattern. Evidence has shown that biomass smoke exposure affects the airway, predominantly the small airways causing anthracofibrosis and peribronchiolar fibrosis changes that will clinically translate into chronic bronchitis symptoms, with a high impact on the quality of life. In this review, we focus especially on the main epidemiological and clinical differences between COPD secondary to biomass exposure and COPD caused by tobacco exposure.

Chronic bronchitis: High prevalence in never smokers and underdiagnosis- A population-based study in Colombia.

The objective of the article was to establish the prevalence, underdiagnosis, and risk factors of chronic bronchitis (CB) in a general population in five Colombian cities. Cross-sectional study using a probabilistic sampling technique in five Colombian cities was adopted. The CB definition was "cough and expectoration for three or more months per year for at least two consecutive years." Underdiagnosis was considered in subjects with clinical definition without previous medical diagnosis. Univariate χ2 or Student's t-test and logistic regression analysis were used. The study included 5539 subjects. The prevalence was 5.5%, the underdiagnosis 50.3%, and 33.7% of the cases were in nonsmokers (53.6% in women vs. 16.9% in men, p < 0.001). The adjusted risk factors were living in Bogota, current smoking, male, age ≥ 64 years, low education, indoor wood smoke exposure, and occupational exposure to vapors, gases, dust, and fumes. CB is a common disease among adults in Colombia. The underdiagnosis was high and there were a large proportion of cases in nonsmokers, particularly in women. Our findings support the association of CB with indoor wood smoke and occupational exposures.

Estimation of personal exposure to asbestos of brake repair workers.

Exposure assessments are key tools to conduct epidemiological studies. Since 2010, 28 riveters from 18 brake repair shops with different characteristics and workloads were sampled for asbestos exposure in Bogotá, Colombia. Short-term personal samples collected during manipulation activities of brake products, and personal samples collected during non-manipulation activities were used to calculate 103 8-h TWA PCM-equivalent personal asbestos concentrations. The aims of this study are to identify exposure determinant variables associated with the 8-h TWA personal asbestos concentrations among brake mechanics, and propose different models to estimate potential asbestos exposure of brake mechanics in an 8-h work-shift. Longitudinal-based multivariate linear regression models were used to determine the association between personal asbestos concentrations in a work-shift with different variables related to work tasks and workload of the mechanics, and some characteristics of the shops. Monte Carlo simulations were used to estimate the 8-h TWA PCM-Eq personal asbestos concentration in work-shifts that had manipulations of brake products or cleaning activities of the manipulation area, using the results of the sampling campaigns. The simulations proposed could be applied for both current and retrospective studies to determine personal asbestos exposures of brake mechanics, without the need of sampling campaigns or historical data of air asbestos concentrations.

Factors Associated With Non-compliance of Asbestos Occupational Standards in Brake Repair Workers.

Asbestos and non-asbestos containing brake products are currently used in low- and middle-income countries like Colombia. Because brake products are distributed detached from their supports, they require manipulation before installation, which release fibers and expose workers. Previous studies of our research group have documented exposures in excess of the widely accepted 0.1 f/cm(3) exposure guideline. The aim of this study is to identify factors associated with non-compliance of the 8-h time weighted average (TWA) 0.1 f/cm(3) asbestos occupational limit among brake mechanics (i.e. riveters). Eighteen brake repair shops (BRS) located in Bogotá (Colombia) were sampled during 3 to 6 consecutive days for the entire work-shift. Personal and short-term personal samples were collected following NIOSH methods 7400 and 7402. Longitudinal based logistic regression models were used to determine the association between the odds of exceeding the 8-h TWA 0.1 f/cm(3) asbestos occupational limit and variables such as type of tasks performed by workers, workload (number of products manipulated daily), years of experience as riveters, and shop characteristics. These models can be used to estimate the odds of being currently or historically overexposed when sampling data do not exist. Since the information required to run the models can vary for both retrospective and current asbestos occupational exposure studies, three models were constructed with different information requirements. The first model evaluated the association between the odds of non-compliance with variables related to the workload, the second model evaluated the association between the odds of non-compliance with variables related to the manipulation tasks, and the third model evaluated the association between the odds of non-compliance with variables related with both the type of tasks performed by workers and the workload. Variables associated with the odds of non-compliance included conducting at least one manipulation activity with beveling and grinding of asbestos and non-asbestos containing brake products during the work shift, the location of the worker in the shop during non-manipulation activities, cleaning activities of the manipulation area, the years of experience working as riveters, and the number of asbestos and non-asbestos containing brake products manipulated daily. These models could be useful for current and retrospective occupational studies, in determining the odds of non-compliance of the asbestos occupational limit among brake mechanics.

Is Chronic Obstructive Pulmonary Disease Caused by Wood Smoke a Different Phenotype or a Different Entity? / Enfermedad pulmonar obstructiva crónica por humo de leña: ¿un fenotipo diferente o una entidad distinta?

Around 40% of the world's population continue using solid fuel, including wood, for cooking or heating their homes. Chronic exposure to wood smoke is a risk factor for developing chronic obstructive pulmonary disease (COPD). In some regions of the world, this can be a more important cause of COPD than exposure to tobacco smoke from cigarettes. Significant differences between COPD associated with wood smoke (W-COPD) and that caused by smoking (S-COPD) have led some authors to suggest that W-COPD should be considered a new COPD phenotype. We present a review of the differences between W-COPD and S-COPD. On the premise that wood smoke and tobacco smoke are not the same and the physiopathological mechanisms they induce may differ, we have analyzed whether W-COPD can be considered as another COPD phenotype or a distinct nosological entity.

Determinants of underdiagnosis of COPD in national and international surveys.

BACKGROUND: COPD ranks within the top three causes of mortality in the global burden of disease, yet it remains largely underdiagnosed. We assessed the underdiagnosis of COPD and its determinants in national and international surveys of general populations. METHODS: We analyzed representative samples of adults aged ≥ 40 years randomly selected from well-defined administrative areas worldwide (44 sites from 27 countries). Postbronchodilator FEV1/FVC < lower limit of normal (LLN) was used to define chronic airflow limitation consistent with COPD. Undiagnosed COPD was considered when participants had postbronchodilator FEV1/FVC < LLN but were not given a diagnosis of COPD. RESULTS: Among 30,874 participants with a mean age of 56 years, 55.8% were women, and 22.9% were current smokers. Population prevalence of (spirometrically defined) COPD ranged from 3.6% in Barranquilla, Colombia, to 19.0% in Cape Town, South Africa. Only 26.4% reported a previous lung function test, and only 5.0% reported a previous diagnosis of COPD, whereas 9.7% had a postbronchodilator FEV1/FVC < LLN. Overall, 81.4% of (spirometrically defined) COPD cases were undiagnosed, with the highest rate in Ile-Ife, Nigeria (98.3%) and the lowest rate in Lexington, Kentucky (50.0%). In multivariate analysis, a greater probability of underdiagnosis of COPD was associated with male sex, younger age, never and current smoking, lower education, no previous spirometry, and less severe airflow limitation. CONCLUSIONS: Even with substantial heterogeneity in COPD prevalence, COPD underdiagnosis is universally high. Because effective management strategies are available for COPD, spirometry can help in the diagnosis of COPD at a stage when treatment will lead to better outcomes and improved quality of life.

Prevalence, risk factors and underdiagnosis of asthma and wheezing in adults 40 years and older: A population-based study.

OBJECTIVE: There are differences in the prevalence and risk factors of asthma around the world. The epidemiological situation of adults 40 years and older is not well established. Our aim was to determine the prevalence, underdiagnosis and risk factors of asthma and wheezing in adults in Colombia. METHODS: A cross-sectional, population-based study including 5539 subjects from 40 to 93 years selected by a probabilistic sampling technique in five cities was conducted. MEASUREMENTS: respiratory symptoms and risk factors questionnaire and spirometry. DEFINITIONS: (a) Wheezing: Affirmative answer to the question "have you ever had two or more attacks of "wheezes" causing you to feel short of breath?" (b) Asthma: Wheezing definition and FEV1/FVC post-bronchodilator ≥ 70%. (c) Underdiagnosis: Asthma definition without a physician-diagnosis. Logistic regression was used for exploring risk factors. RESULTS: Prevalence of asthma was 9.0% (95% CI: 8.3-9.8) and wheezing 11.9% (95% CI: 11.0-12.8). Asthma underdiagnosis was 69.9% and increased to 79.0% in subjects 64 years or older. The risk factors related to asthma and/or wheezing were: living in Bogota or Medellin, female gender, first degree relative with asthma, respiratory disease before 16 years of age, obesity, no education, indoor wood smoke exposure and occupational exposure to dust particles, gases or fumes. CONCLUSION: We described the epidemiologic situation of asthma in adults 40 years and older in Colombia. In addition to some recognized risk factors, our data supports the association of indoor wood smoke and occupational exposures with asthma and wheezing. Underdiagnosis of asthma in adults was high, particularly in older subjects.

Sobrevida de pacientes con fibrosis pulmonar idiopática a la altura de Bogotá (2640 m) / Survival of patients with idiopathic pulmonary fibrosis at the altitude of Bogota (2640 m)

Resumen Introducción: la sobrevida promedio de pacientes con fibrosis pulmonar idiopática (FPI) anivel del mar es de dos a tres años. Desconocemos su comportamiento en Bogotá, ciudad situadaa gran altura (2640 metros), donde hay mayor hipoxemia, factor asociado en la literatura con malpronóstico. El objetivo del estudio es describir, en una cohorte de pacientes con FPI, la sobreviday las características clínicas y funcionales en el momento del diagnóstico. Material y métodos: pacientes con diagnóstico de FPI confirmado por biopsia o por criteriosclínicos, radiológicos y funcionales. Se utilizó el análisis de sobrevida de Kaplan Meier y la prueba log rank. Resultados: cuarenta pacientes, 50% mujeres, con edad de 59.1±13 años y biopsia en52.5%. Al diagnóstico, PaO2: 48.5±11.2 mmHg, CVF: 61.5±16.8 %, CPT: 66.1±11.7 %, D LCO: 39.5±12.4%. La sobrevida desde el diagnóstico fue 42 meses (IC 95% 25.3-58.7 meses) ydesde el inicio de los síntomas 50 meses (IC 95% 40.3-59.7 meses). No hubo diferencias enla sobrevida por sexo, historia de tabaquismo, forma de diagnóstico (biopsia o no biopsia),variables gasométricas y de función pulmonar. Hubo una menor sobrevida en mayores de 60años (23 vs. 72 meses, p=0.03). Conclusiones: la sobrevida de pacientes con FPI en Bogotá con hipoxemia significativa aldiagnóstico, fue similar a la descrita en estudios a nivel del mar. La edad mayor de 60 años se relacionó con mal pronóstico. (Acta Med Colomb 2014; 39: 15-20).

Abstract Introduction: the mean survival of patients with idiopathic pulmonary fibrosis (IPF) at sea level is two to three years. We don't know its behavior in Bogotá, a city at high altitude (2640 meters), where there is greater hypoxemia, factor associated in the literature with poor prognosis. The objective of the study is to describe, in a cohort of patients with IPF survival and clinical and functional characteristics at the time of diagnosis. Methods: patients diagnosed with IPF confirmed by biopsy or by clinical, radiological and functional criteria. Survival analysis of Kaplan Meier and log rank test was utilized. Results: forty patients , 50% women with age 59.1 ± 13 years. 52.5% had biopsy . At diagnosis, PaO2: 48.5 ± 11.2 mmHg, FVC: 61.5 ± 16.8%, CPT: 66.1 ± 11.7%, DLCO: 39.5 ± 12.4%. Survival from diagnosis was 42 months (95% CI 25.3-58.7 months) and from the onset of symptoms 50 months (95% CI 40.3-59.7 months). There was no difference in survival by sex, smoking history, form of diagnosis (biopsy or not biopsy), blood gas and pulmonary function variables. There was a lower survival in patients older than 60 years (23 vs. 72 months, p = 0.03). Conclusions: the survival of patients with IPF in Bogota with significant hypoxemia at diagnosis was similar to that described in studies at sea level. Age older than 60 years was associated with poor prognosis. (Acta Med Colomb 2014; 39: 15-20).

Tomographic and functional findings in severe COPD: comparison between the wood smoke-related and smoking-related disease.

OBJECTIVE: Wood smoke exposure is a risk factor for COPD. For a given degree of airway obstruction, the reduction in DLCO is smaller in individuals with wood smoke-related COPD than in those with smoking-related COPD, suggesting that there is less emphysema in the former. The objective of this study was to compare HRCT findings between women with wood smoke-related COPD and women with smoking-related COPD. METHODS: Twenty-two women with severe COPD (FEV1/FVC ratio < 70% and FEV1 < 50%) were divided into two groups: those with wood smoke-related COPD (n = 12) and those with smoking-related COPD (n = 10). The two groups were compared regarding emphysema scores and airway involvement (as determined by HRCT); and functional abnormalities-spirometry results, DLCO, alveolar volume (VA), the DLCO/VA ratio, lung volumes, and specific airway resistance (sRaw). RESULTS: There were no significant differences between the two groups in terms of FEV1, sRaw, or lung hyperinflation. Decreases in DLCO and in the DLCO/VA ratio were greater in the smoking-related COPD group subjects, who also had higher emphysema scores, in comparison with the wood smoke-related COPD group subjects. In the wood smoke-related COPD group, HRCT scans showed no significant emphysema, the main findings being peribronchial thickening, bronchial dilation, and subsegmental atelectasis. CONCLUSIONS: Female patients with severe wood smoke-related COPD do not appear to develop emphysema, although they do show severe airway involvement. The reduction in DLCO and VA, with a normal DLCO/VA ratio, is probably due to severe bronchial obstruction and incomplete mixing of inspired gas during the determination of single-breath DLCO.

Diferencias tomográficas y funcionales entre la EPOC severa relacionada con humo de leña y con cigarrillo: comparison between the wood smoke-related and smoking-related disease / Tomographic and functional findings in severe COPD

OBJETIVO: La exposición a humo de leña es factor de riesgo para EPOC. A diferencia de la EPOC por cigarrillo (EPOC-C), para un mismo nivel de obstrucción, en la EPOC por leña (EPOC-L), la DLCO está menos disminuida, sugiriendo menos enfisema. Por tanto, el objetivo de este estudio fue comparar los hallazgos en la TCAR en mujeres con EPOC-L y con EPOC- C. MÉTODOS: Veintidós mujeres con EPOC severa (VEF1/CVF < 70% y VEF1 < 50%) fueron divididas en dos grupos: las expuestas a leña (EPOC-L; n = 12) y las expuestas a cigarrillo (EPOC-C; n = 10). Se compararon los dos grupos con respecto al puntaje de enfisema y el compromiso de la vía aérea en la TCAR, las anormalidades funcionales en la espirometría, la DLCO, los volúmenes pulmonares y la resistencia específica de la vía aérea (sRaw). RESULTADOS: Los dos grupos tuvieron VEF1, sRaw e hiperinflación pulmonar similares. En el grupo EPOC-C, hubo mayor disminución de la DLCO y de la DLCO/VA y mayor puntaje de enfisema. En el grupo EPOC-L, no encontramos enfisema significativo en la TCAR. Los hallazgos principales fueron engrosamiento peribronquial, dilataciones bronquiales y atelectasias subsegmentarias. CONCLUSIONES: En pacientes con EPOC-L severa no hay enfisema en la TCAR. El hallazgo más importante es el compromiso severo de la vía aérea. La disminución de la DLCO y del VA con DLCO/VA normal es probablemente determinada por la obstrucción bronquial severa y la mezcla incompleta del gas inspirado en la maniobra de la respiración única de la prueba de difusión.

OBJECTIVE: Wood smoke exposure is a risk factor for COPD. For a given degree of airway obstruction, the reduction in DLCO is smaller in individuals with wood smoke-related COPD than in those with smoking-related COPD, suggesting that there is less emphysema in the former. The objective of this study was to compare HRCT findings between women with wood smoke-related COPD and women with smoking-related COPD. METHODS: Twenty-two women with severe COPD (FEV1/FVC ratio < 70% and FEV1 < 50%) were divided into two groups: those with wood smoke-related COPD (n = 12) and those with smoking-related COPD (n = 10). The two groups were compared regarding emphysema scores and airway involvement (as determined by HRCT); and functional abnormalities-spirometry results, DLCO, alveolar volume (VA), the DLCO/VA ratio, lung volumes, and specific airway resistance (sRaw). Results: There were no significant differences between the two groups in terms of FEV1, sRaw, or lung hyperinflation. Decreases in DLCO and in the DLCO/VA ratio were greater in the smoking-related COPD group subjects, who also had higher emphysema scores, in comparison with the wood smoke-related COPD group subjects. In the wood smoke-related COPD group, HRCT scans howed no significant emphysema, the main findings being peribronchial thickening, bronchial dilation, and subsegmental atelectasis. CONCLUSIONS: Female patients with severe wood smoke-related COPD do not appear to develop emphysema, although they do show severe airway involvement. The reduction in DLCO and VA, with a normal DLCO/VA ratio, is probably due to severe bronchial obstruction and incomplete mixing of inspired gas during the determination of single-breath DLCO.