Evolución clínico funcional de pacientes con fibrosis quística tratados con lumacaftor/ivacaftor en un centro pediátrico. Serie de casos / Clinical and functional course of patients with cystic fibrosis treated with lumacaftor/ivacaftor at a children's hospital. A case series

Los moduladores de la proteína reguladora transmembrana de fibrosis quística (CFTR) tratan el defecto de esta proteína. El objetivo es describir la evolución de niños con fibrosis quística tratados con lumacaftor/ivacaftor. Se trata de una serie de 13 pacientes de 6 a 18 años con ≥ 6 meses de tratamiento. Se analizaron el volumen espiratorio forzado en el primer segundo (VEF1), puntaje Z del índice de masa corporal (IMC), antibioticoterapia/año, antes del tratamiento y durante 24 meses posteriores. A los 12 meses (9/13) y 24 meses (5/13), la mediana de cambio del porcentaje del predicho VEF1 (ppVEF1) fue de 0,5 pp [-2-12] y 15 pp [8,7-15,2], y del puntaje Z de IMC de 0,32 puntos [-0,2-0,5] y 1,23 puntos [0,3-1,6]. El primer año (11/13) la mediana de días de uso de antibiótico disminuyó de 57 a 28 (oral) y de 27 a 0 (intravenoso). Dos niños evidenciaron eventos adversos asociados.

Cystic fibrosis transmembrane regulator (CFTR) modulators treat defective CFTR protein. Our objective is to describe the course of children with cystic fibrosis treated with lumacaftor/ivacaftor. This is a case series of 13 patients aged 6 to 18 years with ≥ 6 months of treatment. Forced expiratory volume in the first second (FEV1), body mass index (BMI) Z-score, antibiotic therapy/year, before treatment and for 24 months after treatment were analyzed. At 12 months (9/13) and 24 months (5/13), the median change in the percent predicted FEV1 (ppFEV1) was 0.5 pp (-2­12) and 15 pp (8.7­15.2) and the BMI Z-score was 0.32 points (-0.2­0.5) and 1.23 points (0.3­1.6). In the first year, in 11/13 patients, the median number of days of antibiotic use decreased from 57 to 28 (oral) and from 27 to 0 (intravenous). Two children had associated adverse events.

Relación entre dimensiones antropométricas de tronco y valores de espirometría / Association between anthropometric dimensions of trunk and spirometry indices

Los objetivos del presente estudio fueron primero evaluar la asociación de dimensiones antropométricas de tórax y tronco con índices espirométricos, segundo, ajustar una ecuación de predicción con dimensiones antropométricas de tronco y tercero, comparar nuestro modelo predictivo con dos ecuaciones diagnósticas. Se evaluaron 59 estudiantes universitarios entre 20 y 40 años, de ambos sexos, sin hábito tabáquico. Las variables consideradas fueron: edad, sexo, peso, estatura, diámetro transverso de tórax, diámetro anteroposterior de tórax, perímetro de tórax, altura de tórax, altura de tronco, flujo espiratorio máximo (FEM), volumen espiratorio forzado en el primer segundo (VEF1) y capacidad vital forzada (CVF). Se utilizó el análisis de regresión múltiple para estimar los valores espirométricos en función de las variables demográficas y antropométricas. La CVF y el VEF1 tienen asociación lineal directa con el diámetro transverso de tórax, altura de tórax, perímetro de tórax y altura de tronco. Se ajustó una ecuación de regresión lineal múltiple que indicó que es posible estimar la CVF y el VEF11 en función de la altura de tronco y el perímetro de tórax para ambos sexos. Estas variables son capaces de explicar el 74 % de los valores de CVF y el 68 % de los valores de VEF1. Al comparar los valores obtenidos por nuestras ecuaciones predictivas con las ecuaciones de referencia nacional observamos que nuestros resultados son más cercanos a los de Quanjer et al. (2012) que a los de Knudson et al. (1983). La altura de tronco y el perímetro de tórax tienen asociación directa con el VEF1 y CVF y son buenos predictores del VEF1 y CVF en estudiantes universitarios. Nuestros valores estimados son más cercanos a las ecuaciones de Quanjer et al. (2012) en comparación a las estimaciones de Knudson (1983).

SUMMARY: The purposes of the present study were first to evaluate the association between anthropometric dimensions of the thorax and trunk with spirometric indices, second, to fit a prediction equation with anthropometric dimensions of the trunk, and third, to compare our predictive model with two diagnostic equations. Fifty-nine university students between 20 and 40 years old, of both sexes and non-smokers were recruited. Variables considered were age, sex, weight, height, chest transverse diameter, chest anteroposterior diameter, chest perimeter, chest height, trunk height, maximum expiratory flow (PEF), forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC). Multiple regression analysis was used to estimate spirometric values based on demographic and anthropometric variables. FVC and FEV1 have a direct linear association with chest transverse diameter, chest height, chest circumference, and trunk height. A multiple linear regression equation was fitted, indicating that it is possible to estimate FVC and FEV1 as a function of trunk height and chest girth for both sexes. These variables can explain 74% of the FVC values and 68% of the FEV1 values. Comparing the values obtained by our predictive equations with the national reference equations, we observe that our results are closer to those of Quanjer et al. (2012) than to those of Knudson et al. (1983). Trunk height and chest circumference have a direct association with FEV1 and FVC and are good predictors of FEV1 and FVC in university students. Our estimated values are closer to Quanjer et al. (2012) than Knudson et al. (1983) prediction equations.

Trayectorias de función pulmonar en asma persistente: del preescolar al escolar / Lung function trajectories in persistent asthma: from preschool to schoolchildren

Introducción: Se han informado patrones de deterioro temprano de la función pulmonar en el asma pediátrica. Nuestro objetivo fue identificar las trayectorias de la función pulmonar en la espirometría, desde la edad preescolar hasta la edad escolar. Materiales: Estudio prospectivo realizado entre el 2016 y el 2021. Se reclutaron pacientes con asma persistente a quienes se les realizó oscilometría de impulso (IOS)-espirometría al inicio y después de 3 años. La espirometría anormal se definió de acuerdo con las guías ATS/ERS. Métodos: se utilizó χ2 y ANOVA para comparar las características clínicas y promedios de parámetros de la espirometría e IOS entre trayectorias. Resultados: 86 pacientes, promedio de edad 5,3 y 8,3 años en su primera y segunda evaluación. El 70,9% de los pacientes mantuvo la espirometría normal en ambas evaluaciones (trayectoria 1), el 9,3% presentó espirometría preescolar anormal que normalizó en la edad escolar (trayectoria 2) y el 19,8% espirometría en anormal en ambas evaluaciones (trayectoria 3). La trayectoria 3 registró menor peso promedio al nacer (2,4 kg vs 3,02 kg p = 0,04), mayor promedio de exacerbaciones (5,3 vs 2,01 p = 0,00002), mayor promedio de hospitalizaciones (0,61 vs 0,16 p = 0,04), parámetros promedio más bajos en espirometría (relación VEF1/CVF %, relación VEF0,75/CVF %, VEF0,75 L, VEF0,5 L), promedios más bajos en X5 kPa/Ls y más altos en AX kPa/Ls, que la trayectoria 1. Conclusiones: La trayectoria 1 fue la más frecuente, con persistencia de función pulmonar normal. La trayectoria 3, la segunda más frecuente, inició seguimiento con función pulmonar disminuida en la espirometría y disfunción de vía aérea pequeña en el IOS que se mantuvo en la edad escolar. Los niños que siguieron la trayectoria 3 tuvieron menor peso al nacer, más exacerbaciones y hospitalizaciones que los niños de la trayectoria 1.

Introduction: Patterns of early decline in lung function have been reported in pediatric asthma. Our objective was to identify pulmonary function trajectories in spirometry, from preschool age to school age. Materials: Prospective study conducted between 2016 and 2021. Patients with persistent asthma who underwent impulse oscillometry (IOS)-spirometry at baseline and after 3 years were recruited. Abnormal spirometry was defined according to ATS/ERS guidelines. Methods: χ2 and ANOVA was used to compare clinics characteristics and means of IOS-spirometry parameters between trajectories. Results: 86 patients, mean age of 5,3 and 8,3 years in their first and second evaluation. 70.9% of the patients maintained normal spirometry in both evaluations (Track 1), 9.3% presented abnormal preschool spirometry that normalized at school age (Track 2) and 19.8% abnormal spirometry in both evaluations (Track 3). Trajectory 3 had a lower average birth weight (2,4 kg vs 3,02 kg p = 0,04), higher average of exacerbations (5,3 vs 2,01 p = 0,00002), higher average of hospitalizations (0,61 vs 0,16 p = 0,04), lowest averages parameters in spirometry (FEV1/FVC % ratio, FEV0,75/FVC % ratio, FEV0,75 L, FEV0,5 L), lower average in X5 kPa/Ls and higher in AX kPa/Ls, than trajectory 1. Conclusions: Trajectory 1 was the most common, with persistent normal lung function. Trajectory 3, the second most frequent, started follow-up with decreased lung function in spirometry and small airway disfunction in the IOS that were maintained at school age. Children who followed trajectory 3 had lower birth weight, more exacerbations, and hospitalizations than children in trajectory 1.

Consultas a urgencia y valores espirométricos tras el reemplazo de salmeterol/fluticasona por budesonida/formoterol en pacientes con asma moderada a grave / Emergency consultations and spirometric values after replacement of salmeterol/fluticasone with budesonide/formoterol in patients with moderate to severe asthma

El asma se caracteriza por su impacto deletéreo que incluye gran coste económico para el sistema de salud. En pacientes con asma mal controlada a pesar del tratamiento, se propone un régimen de mantenimiento con corticoides inhalados y formoterol. El objetivo del presente estudio observacional retrospectivo fue evaluar las modificaciones espirométricas tras el cambio del medicamento controlador en pacientes con asma moderada a severa asistidos en el Hospital Clínico de Magallanes de Punta Arenas, así como también cuantificar la modificación en el número de exacerbaciones graves (consulta a un servicio de urgencia y/u hospitalización por asma). Participaron 61 adultos con asma moderada a severa (mediana de edad: 60 años [rango: 21-87], mujeres: 69,4%; comorbilidad atópica/alérgica: 79%; otras comorbilidades: 46,8%) en los que se cambió el tratamiento con fluticasona/salmeterol 250/25 μg por budesónida/formoterol 160/4,5 μg. No se observaron cambios significativos en los índices espirométricos tras el cambio. Con el tratamiento inicial, el 46,9% presentó ≥ 1 visita a urgencias (total: 50 consultas). Tras el cambio por budesonida/formoterol, el 21% requirió al menos una visita a urgencias (total: 14 consultas; p < 0,01). La proporción de pacientes con ≥ 2 consultas a urgencias fue de 19,7% con el tratamiento basal y de 1,6% tras el cambio a budesonida/formoterol (p < 0,01). No se observaron diferencias significativas en la cantidad de hospitalizaciones. En este estudio del mundo real de pacientes con asma moderada a grave, el cambio del tratamiento a budesonida/formoterol se asoció con reducción significativa de las consultas a urgencias, a pesar de no detectarse cambios de significación estadística en los índices espirométricos habituales.

Asthma is characterized by its deleterious impact, including a high cost to the healthcare system. In patients with poorly controlled asthma despite treatment, a maintenance regimen of inhaled corticosteroids and formoterol is proposed. The aim of this retrospective, observational study was to evaluate the spirometric changes after switching the controller medication in patients with moderate to severe asthma attended in our institution ("Hospital Clínico de Magallanes"), as well as the variation in the number of severe exacerbations (consultation to an emergency department and/or hospitalization for asthma). Sixty-one adults with moderate to severe asthma (median age: 60 years-old [range: 21-87], women: 69.4%; atopic/allergic comorbidity: 79%; other comorbidities: 46.8%) in whom treatment with fluticasone/salmeterol 250/25 μg was switched to budesonide/formoterol 160/4.5 μg participated in our study. No significant changes in spirometric parameters were observed after the replacement treatment. With the initial treatment, 46.9% patients presented ≥ 1 visit to the emergency department (total: 50 visits). After the switch to budesonide/formoterol, 21% required at least one emergency department visit (total: 14 consultations; p < 0.01). The proportion of patients with ≥ 2 emergency department visits was 19.7% with baseline treatment and 1.6% after switching to budesonide/formoterol (p < 0.01). No significant differences were observed in the number of hospitalizations. In this real-world study of moderate to severe asthma patients, switching to budesonide/formoterol was associated with a significant reduction in emergency department visits, despite no statistically significant changes in the usual spirometric parameters.

Función pulmonar: ¿Debemos cambiar la forma de calcular la respuesta broncodilatadora en la espirometría en niños? / Should we change the way we calculate the bronchodilator response in children's spirometry?

Tradicionalmente se ha definido la respuesta broncodilatadora (RB) positiva como una mejoría ≥ de 12 % del VEF1. En el año 2022 se publica una Guía sobre la interpretación de función la pulmonar de la Sociedad Americana de Tórax y la Sociedad Europea de Enfermedades Respiratorias, donde se propone que la RB debe expresarse como el cambio porcentual del VEF1 en relación con el VEF1 predicho y que un cambio ≥ 10 % indica una RB positiva. Las sociedades científicas en Chile están evaluando estas recomendaciones para decidir su adecuada implementación en pediatría.

Traditionally, a positive bronchodilator (BR) response has been defined as a ≥ 12% improvement in FEV1. In the year 2022, a Guide on the interpretation of pulmonary function of the American Thoracic Society and the European Society of Respiratory Diseases was published, where it was proposed that BR should be expressed as the percent change in FEV1 relative to predicted FEV1 and that a change ≥ 10% indicates a positive BR. Scientific societies in Chile are evaluating these recommendations to decide their proper implementation in pediatrics.

Effect of respiratory filter on pulmonary function in occupational health examination / 中华劳动卫生职业病杂志

Objective: To explore the influence and significance of respiratory filter on the judgment of pulmonary function and the conclusion of occupational health examination in occupational health examination. Methods: From August to November 2020, 252 occupational health examinees were randomly selected as the research objects, and the lung function was examined with the respiratory filter bite and the straight cylinder bite without filter, respectively. The lung function examination indexes and the qualification rate of lung function examination were analyzed and compared between the two groups, and the diagnostic criteria of lung function examination was corrected. Results: 252 subjects were 36 (30, 42) years old. The qualified rate of lung function examination with respiratory filter bite (28.17%, 71/252) was lower than that with straight cylinder bite (34.92%, 88/252) , the difference was statistically significant (P<0.05) . The percentage of forced vital capacity in normal predicted value (FVC%) , percentage of forced expiratory volume in the first second in normal predicted value (FEV(1)%) , and percentage of forced expiratory volume in the first second in forced vital capacity (FEV(1)/FVC%) of subjects using respiratory filter bite were lower than those using the straight cylinder bite (P<0.05) . The corrected diagnostic criteria of pulmonary function were FVC%>78%, FEV(1)%>77%, FEV(1)/FVC%>68%. There was no significant difference between the qualified rate of the respiratory filter bite lung function test calculated according to the corrected diagnostic criteria (35.71%, 90/252) and the qualified rate of the straight cylinder bite lung function test calculated according to the original diagnostic criteria (34.92%, 88/252) (P>0.05) . Conclusion: In occupational health examination, the use of respiratory filter may affect the results of pulmonary function examination. The diagnostic criteria of pulmonary function can be corrected according to different filtering effects to ensure the accuracy of the conclusions of occupational health examination.

A randomized clinical trial on inhaled ciclesonide for managing acute asthma in the emergency room

ABSTRACT BACKGROUND: Use of inhaled corticosteroids for managing acute asthma exacerbations has been tested since the 1990s. OBJECTIVE: To compare high doses of inhaled ciclesonide with systemic hydrocortisone for managing acute asthma exacerbations in the emergency department. DESIGN AND SETTING: Double-blind, randomized clinical trial in the public healthcare system of the city of São Paulo. METHODS: Fifty-eight patients with moderate or severe asthma with peak flow < 50% of predicted were randomized into two groups. Over the course of four hours, one group received 1440 mcg of inhaled ciclesonide plus hydrocortisone-identical placebo (ciclesonide + placebo), while the other received 500 mg of intravenous hydrocortisone plus ciclesonide-identical placebo (hydrocortisone + placebo). Both groups received short-acting bronchodilators (fenoterol hydrobromide and ipratropium bromide). The research protocol included spirometry, clinical evaluation, vital signs and electrocardiogram monitoring. Data were obtained at 30 (baseline), 60, 90, 120, 180, and 240 minutes. We compared data from baseline to hour 4, between and within groups. RESULTS: Overall, 31 patients received ciclesonide + placebo and 27 received hydrocortisone + placebo. Inhaled ciclesonide was as effective as intravenous hydrocortisone for improving clinical parameters (Borg-scored dyspnea, P = 0.95; sternocleidomastoid muscle use, P = 0.55; wheezing, P = 0.55; respiratory effort, P = 0.95); and spirometric parameters (forced vital capacity, P = 0.50; forced expiratory volume in the first second, P = 0.83; peak expiratory flow, P = 0.51). CONCLUSIONS: Inhaled ciclesonide was not inferior to systemic hydrocortisone for managing acute asthma exacerbations, and it improved both clinical and spirometric parameters. TRIAL REGISTRATION: RBR-6XWC26 - Registro Brasileiro de Ensaios Clínicos (http://www.ensaiosclinicos.gov.br/rg/RBR-6xwc26/).

Correlation Analysis of the Lung Volume Reduction and the Lung Function Loss after the Thoracoscopic Lobectomy / 中国肺癌杂志

BACKGROUND@#To investigate the correlation between the reduction of lung volume and the degree of lung function damage after lobectomy.@*METHODS@#A total of 131 patients (72 males and 59 females) who underwent thoracoscopic lobectomy in the First Affiliated Hospital of Suzhou University from January 2019 to July 2020 (including thoracoscopic resection of left upper lobe, left lower lobe, right upper lobe, right middle lobe and right lower lobe). In order to compare the difference between postoperative pulmonary function and preoperative pulmonary function, the pulmonary function measurements were recorded at 7 days before operation, and 3 months, 6 months and 1 year after operation. Forced expiratory volume in 1 second (FEV1) was used as the main evaluation parameter of pulmonary function. The original lung volume and the remaining lung volume at each stage were calculated by Mimics Research 19.0 software. The correlation between lung volume and lung function was analyzed.@*RESULTS@#FEV1 in postoperative patients was lower than that before operation, and the degree of decline was positively correlated with the resection volume of lung lobes (the maximum value was shown in the left lower lobe group). Significantly, there was no significant difference in the degree of pulmonary function reduction between 3 months, 6 months and 1 year after operation.@*CONCLUSIONS@#The decrease of lung tissue volume after lobectomy is the main reason for the decrease of lung function, especially in the left lower lobe. And 3 months after lobectomy can be selected as the evaluation node of residual lung function.

Study on the Benefit of Postoperative Exercise Rehabilitation in Patients with Lung Cancer Complicated with Chronic Obstructive Pulmonary Disease / 中国肺癌杂志

BACKGROUND@#Chronic obstructive pulmonary diseases (COPD) affects 45%-63% of lung cancer patients worldwide. Lung cancer patients complicated with COPD have decreased cardiopulmonary function and increased perioperative risk, and their postoperative exercise endurance and lung function are significantly lower than those with conventional lung cancer. Previous studies have shown that postoperative exercise training can improve the exercise endurance of unselected lung cancer patients, but it is unclear whether lung cancer patients with COPD can also benefit from postoperative exercise training. This study intends to explore the effects of postoperative exercise training on exercise endurance, daily activity and lung function of lung cancer patients with COPD.@*METHODS@#Seventy-four patients with non-small cell lung cancer (NSCLC) complicated with COPD who underwent pneumonectomy in the lung cancer center of West China Hospital of Sichuan University from August 5, 2020 to August 25, 2021 were prospectively analyzed. They were randomly divided into exercise group and control group; The patients in the two groups received routine postoperative rehabilitation in the first week after operation, and the control group was given routine nursing from the second week. On this basis, the exercise group received postoperative exercise rehabilitation training for two weeks. Baseline evaluation was performed 3 days before operation and endpoint evaluation was performed 3 weeks after operation.@*RESULTS@#The exercise endurance, daily activity and pulmonary function test results of the two groups decreased from baseline to the end point. However, after the operation and intervention program, the maximum oxygen consumption of Cardiopulmonary Exercise Test and the walking distance of 6-Minute Walking Test in the exercise group were significantly better than those in the control group [(13.09±1.46) mL/kg/min vs (11.89±1.38) mL/kg/min, P=0.033; (297±46) m vs (243±43) m, P=0.041]. The average number of we-chat steps in the exercise group was also significantly better than that in the control group (4,381±397 vs 3,478±342, P=0.035). Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) in the exercise group were better than those in the control group, but the difference did not reach a statistically significant level [(1.76±0.19) L vs (1.60±0.28) L, P=0.084; (1.01±0.17) L vs (0.96±0.21) L, P=0.467].@*CONCLUSIONS@#Postoperative exercise rehabilitation training can improve exercise endurance and daily activity ability of patients with lung cancer complicated with COPD and promote postoperative rehabilitation.

Meta-analysis of efficacy and safety of Suhuang Zhike Capsules in treatment of chronic obstructive pulmonary disease / 中国中药杂志

This study aims to evaluate the effectiveness and safety of Suhuang Zhike Capsules in treating chronic obstructive pulmonary disease. The Chinese and English databases were searched(from the establishment to July 2021) for randomized controlled trials(RCTs) on the treatment of chronic obstructive pulmonary disease with Suhuang Zhike Capsules, yielding 130 articles and finally 12 eligible RCTs. The 12 RCTs enrolled a total of 1 159 patients(579 in experimental group, 580 in control group), with 728 males(62.8%) and 431 females(37.2%). Meta-analysis showed that the conventional western medicine combined with Suhuang Zhike Capsules increased clinical efficacy(OR=4.31, 95%CI[2.88, 6.46], Z=7.08, P<0.000 01), forced expiratory volume in one second(FEV1)(SMD=0.88, 95%CI[0.60, 1.16], Z=6.24, P<0.000 01), forced vital capacity(FVC)(SMD=0.96, 95%CI[0.38, 1.55], Z=3.22, P=0.001), forced vital capacity rate of one second(FEV1/FVC%)(SMD=0.85, 95%CI[0.51, 1.19], Z=4.92, P<0.000 01), and maximum voluntary ventilation(MVV)(SMD=0.61, 95%CI[0.39, 0.83], Z=5.40, P<0.000 01) compared with the conventional western medicine alone. The differences in residual volume/total lung capacity(RV/TLC)(SMD=-0.93, 95%CI[-3.38, 1.53], Z=0.74, P=0.46) and adverse reactions(OR=1.39, 95%CI[0.76, 2.56], Z=1.07, P=0.28) are insignificant. The study showed that the conventional western medicine combined with Suhuang Zhike Capsules could improve clinical efficacy and lung functions in the treatment of chronic obstructive pulmonary disease. In addition, the combination had been verified to be safe. However, in view of the uneven method quality, small sample size, and inconsistent outcome indicators of the included studies, higher-quality, multi-center, and large-sample RCTs are needed for further verification.

Caracterización de parámetros del intercambio gaseoso en la Ciudad de México / Characterization of gas exchange parameters in Mexico City

Introducción: en las grandes altitudes, el intercambio gaseoso suele estar deteriorado; en la altitud moderada de la Ciudad de México esto no está aún plenamente definido. Objetivo: caracterizar el intercambio gaseoso en la altitud moderada de la Ciudad de México. Material y métodos: mediante un estudio transversal analítico se estudiaron sujetos nacidos y habitantes de la Ciudad de México, de ambos géneros, con edades de 20 a 59 años sin enfermedad cardiopulmonar. Se registraron sus variables demográficas, espirometría simple y de gasometría arterial. Las diferencias en las variables se calcularon con ANOVA de una vía para grupos independientes y ajuste de Bonferroni. Una p < 0.05 se aceptó como significativa. Resultados: se estudiaron 335 sujetos, de los cuales 168 (50.15%) fueron hombres, la edad grupal fue de 45 ± 11 años, con índice de masa corporal 22.97 ± 1.54 Kg/m2. La relación volumen espiratorio forzado en el primer segundo/Capacidad vital forzada (VEF1/CVF) de 91.58 ± 12.86%. La presión arterial de oxígeno fue de 66 ± 5.02 mmHg, el bióxido de carbono: 32.07 ± 2.66 mmHg, la saturación arterial de oxígeno: 93.03 ± 1.80% y la hemoglobina: 14.07 ± 1.52 gr/dL. Conclusiones: la presión arterial de oxígeno y del bióxido de carbono están disminuidos a la altura de la Ciudad de México.

Background: At high altitude the gas exchange is impaired, in the moderate altitude of Mexico City they are not yet defined. Objective: To characterize the gas exchange in the moderate altitude of Mexico City. Material and methods: Through an analytical cross-sectional study, subjects born and inhabitants of Mexico City, both genders, aged 20 to 59 years without cardiopulmonary disease, were studied. Their demographic variables, simple spirometry and arterial blood gas were recorded. Differences in variables were calculated with one-way ANOVA for independent groups and Bonferroni adjustment. p < 0.05 was accepted as significant. Results: 335 subjects were studied, 168 (50.15%) men. Group age 45 ± 11 years old, body mass index 22.97 ± 1.54 Kg/m2. Forced expiratory volume ratio in the first second / Forced vital capacity (FEV1/FVC) 91.58 ± 12.86%. The arterial oxygen pressure was: 66 ± 5.02 mmHg, carbon dioxide: 32.07 ± 2.66 mmHg, arterial oxygen saturation: 93.0 3 ± 1.80%, and hemoglobin: 14.07 ± 1.52 gr/dL. Conclusions: The arterial oxygen pressure and carbon dioxide are lowered at the Mexico City altitude.

Alteraciones de la función pulmonar medida por espirometría y oscilometría de impulso en niños asmáticos con sobrepeso y obesidad / Alterations in lung function as measured by spirometry and impulse oscillometry in asthmatic children with overweight and obesity

INTRODUCCIÓN: El incremento del índice de masa corporal afecta la función pulmonar en el asma. Objetivo: determinar si existen diferencias entre asmáticos con estado nutricional normal, sobrepeso y obesidad en cuanto a alteraciones de la oscilometría de impulso (IOS) y espirometría. MÉTODO: Estudio realizado en niños y adolescentes con asma persistente. Se practicó sucesivamente IOS y Espirometría pre y post- broncodilatador según criterios ATS/ERS/SER. Los pacientes se clasificaron en: eutróficos (AE), con sobrepeso (ASP) y obesos (AO). Se compararon promedios de valores basales y con respuesta broncodilatadora (RB) en espirometría e IOS, con análisis de varianzas ANOVA y test de Tukey post hoc. Se consideró un poder de 80% y error α de 5%. RESULTADOS: Se analizaron 559 pacientes, promedio de edad 9,2 años, 50,9% varones. AE 52,4%, ASP 31,3% y AO 16,3%. Se encontraron diferencias significativas entre AO vs AE (X5, AX, D5-20, VEF1/CVF, FEF25-75/CVF, RB VEF1), y entre ASP vs AE (AX, D5-20, VEF1/CVF). También se encontraron diferencias significativas en varones, no encontradas en las mujeres (X5, D5-20, VEF1/CVF, RB CVF, RB VEF1). CONCLUSIONES: Los niños asmáticos con sobrepeso y obesidad, tienen un mayor compromiso de los índices de función pulmonar medida por espirometría e IOS que los asmáticos con estado nutricional normal. Existen diferencias de género en las alteraciones espirometría e IOS.

INTRODUCTION: Increased body mass index asthma affects lung function in asthma. Objective: to determine if asthmatics with overweight or obesity have alterations in Impulse oscillometry (IOS) and spirometry compared to eutrophic METHOD: Study carried out in children and adolescents with persistent asthma. IOS-Spirometry pre and post bronchodilator were performed successively according to ATS/ERS/SER criteria. The patients were classified as: eutrophic (AE), overweight (ASP) and obese (OA). Baseline and bronchodilator response (BR) averages were compared in spirometry and IOS with ANOVA and Tukey's post hoc analysis of variance. A power of 80% and α error of 5% were considered. RESULTS: 559 patients were analyzed, mean age 9.2 years, 50.9% male. AE 52.4%, ASP 31.3% and OA 16.3%. Significant differences were found between OA vs AE (X5, AX, D5-20, FEV1/FVC, FEF25-75 / FVC, RB FEV1), and between ASP vs AE (AX, D5-20, FEV1/FVC). Significant differences were also found in men, not women (X5, D5-20, FEV1/FVC, BR FVC, BR FEV1). CONCLUSIONS: Asthmatic children with overweight and obesity have a greater compromise of pulmonary function parameters measured by spirometry and IOS than asthmatics with normal nutritional status. There are gender differences in spirometry and IOS alterations.

Evaluation of the pulmonary function of patients with severe coronavirus 2019 disease three months after diagnosis / Evaluación de la función pulmonar de pacientes con enfermedad grave por coronavirus 2019 tres meses después del diagnóstico

Abstract There are few data regarding the repercussion in the pulmonary function of patients who had severe or critical COVID-19 pneumonia. The objective was to describe these patients´ pulmonary function and establish an association with the severity of the disease (patients with severe or critical pneumonia), the presence of comorbidities, the tomographic involvement and the persistence of dyspnoea. Fifty-five patients were included, 40 (73%) male, media of age 54.9 (11.6) years old and body mass index (BMI) 33.1 (6.09) kg/m2. Fifty (90%) had 1 comorbidity, obesity 67%, arterial hypertension 36%, and diabetes mellitus 35%. Twenty-five (45%) had critical pneumonia. Fifteen (27%) had a spirometric alteration that suggested restriction and 32 (58%) had gas exchange defect. The latter had forced volume capacity (FVC), forced expiratory volume in the first second (FEV1) and carbon monoxide diffusion capacity (DLCO) values significantly lower. Ninety percent presented some degree of involvement in the chest CT scan, ground glass-opacities the most frequent finding. A moderate negative correlation was found between the severity of the tomographic involvement and the DLCO levels. Thirty patients (55%) referred some degree of dyspnoea. Patients with this symptom had DLCO and KCO values below those who did not have dyspnoea: 70.5 vs. 85.1 p = 0.02 and 88 vs. 104 p = 0.02. The presence of abnormal gas exchange is the main characteristic of patients with pulmonary sequelae due to COVID-19. Our study does not show either predictor of evolution towards pulmonary sequelae or an association with the severity of the disease.

Resumen Se conocen pocos datos acerca de la repercusión en la función pulmonar de pacientes que cursaron una neumonía grave o crítica por COVID-19. El objetivo fue describir la función pulmonar de estos pacientes y establecer si existe asociación con la gravedad (neumonía grave o crítica), comorbilidades, compromiso tomográfico y persistencia de disnea. Se incluyeron 55 pacientes, 40 (73%) varones, media de edad 54.9 (11.6) años e índice de masa corporal (IMC) 33.1 (6.09) kg/m2. Cincuenta (90%) tenían una comorbilidad, obesidad 67%, hipertensión arterial 36% y diabetes mellitus 35%. Veinticinco (45%) presentaron neumonía crítica. Se hallaron 15 (27%) con una alteración que sugiere restricción y 32 (58%) presentaron trastorno del intercambio gaseoso. Aquellos con trastorno del intercambio gaseoso, tenían valores de capacidad vital forzada (FVC), volumen espiratorio forzado en el primer segundo (FEV1) y difusión de monóxido de carbono (DLCO) significativamente menores. El 90% tenía algún grado de compromiso en TAC de tórax siendo vidrio esmerilado el hallazgo más frecuente. Se encontró moderada correlación negativa entre gravedad del compromiso tomográfico y nivel de DLCO. A la consulta, 30 (55%) referían algún grado de disnea. Los pacientes con disnea presentaban valores de DLCO y KCO inferiores respecto a los que no referían disnea 70.5 vs. 85.1 p = 0.02 y 88 vs. 104 p = 0.02. La presencia de intercambio anormal de gases es la característica principal de los pacientes con secuelas pulmonares por COVID-19. De nuestro trabajo no surgen predictores para evolución hacia secuela pulmonar ni pudimos asociarlo a la gravedad de la enfermedad.

High-resolution CT pulmonary findings in children with severe asthma

Abstract Objective: To compare quantitative CT parameters between children with severe asthma and healthy subjects, correlating to their clinical features. Methods: We retrospectively analyzed CT data from 19 school-aged children (5-17 years) with severe asthma and 19 control school-aged children with pectus excavatum. The following CT parameters were evaluated: total lung volume (TLV), mean lung density (MLD), CT air trapping index (AT%) (attenuation ≤856 HU), airway wall thickness (AWT), and percentage of airway wall thickness (AWT%). Multi-detector computed tomography (MDCT) data were correlated to the following clinical parameters: forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), forced expiratory flow at 25-75% (FEF 25-75%), FEV1/FVC ratio, sputum and bronchoalveolar lavage analysis, serum IgE levels, and previous hospitalizations due to asthma. Results: Asthma patients presented higher mean values of AT% (23.8 ± 6.7% vs. controls, 9.7 ± 3.2%), AWT (1.46 ± 0.22 mm vs. controls, 0.47 ± −735 ± 28 HU vs. controls, −666 ± 19 HU). Mean AT% was 29.0 ± 4.7% in subjects with previous hospitalization against 19.2 ± 5.0% in those with no prior hospitalization (p < 0.001). AT% presented very strong negative correlations with FVC (r = −0.933, p < 0.001) and FEV1 (r = −0.841, p < 0.001) and a moderate correlation with FEF 25-75% (r = −0.608, p = 0.007). AT% correlation with FEV1/FVC ratio and serum IgE was weak (r = −0.184, p = 0.452, and r = −0.363, p = 0.202) Conclusion: Children with severe asthma present differences in quantitative chest CT scans compared to healthy controls with strong correlations with pulmonary function tests and previous hospitalizations due to asthma.

Exercise-induced desaturation in subjects with non-cystic fibrosis bronchiectasis: laboratory-based tests versus field-based exercise tests / Dessaturação induzida pelo exercício em pacientes com bronquiectasia não fibrocística: testes laboratoriais versus testes clínicos de campo

ABSTRACT Objective: To investigate the validity of field walking tests to identify exercise-induced hypoxemia and to compare cardiorespiratory responses and perceived effort between laboratory-based and field-based exercise tests in subjects with bronchiectasis. Methods: This was a cross-sectional study involving 72 non-oxygen-dependent participants (28 men; mean age = 48.3 ± 14.5 years; and mean FEV1 = 54.1 ± 23.4% of the predicted value). The participants underwent cardiopulmonary exercise testing (CPET) on a treadmill and constant work-rate exercise testing (CWRET) on the same day (1 h apart). In another visit, they underwent incremental shuttle walk testing (ISWT) and endurance shuttle walk testing (ESWT; 1 h apart). Desaturation was defined as a reduction in SpO2 ≥ 4% from rest to peak exercise. Results: CPET results were compared with ISWT results, as were CWRET results with ESWT results. There was no difference in the magnitude of desaturation between CPET and ISWT (−7.7 ± 6.3% vs. −6.6 ± 5.6%; p = 0.10) and between CWRET and ESWT (−6.8 ± 5.8% vs. −7.2 ± 6.3%; p = 0.50). The incremental tests showed an agreement in the magnitude of desaturation in the desaturation and no desaturation groups (42 and 14 participants, respectively; p < 0.01), as did the endurance tests (39 and 16 participants; p < 0.01). The magnitude of desaturation was similar among the participants who did or did not reach at least 85% of the maximum predicted HR. Conclusions: Field exercise tests showed good precision to detect desaturation. Field tests might be an alternative to laboratory tests when the clinical question is to investigate exercise-induced desaturation in subjects with bronchiectasis.

RESUMO Objetivo: Investigar a validade dos testes de caminhada de campo para identificar dessaturação durante o exercício, comparando os testes de exercício laboratoriais e clínicos de campo quanto às respostas cardiorrespiratórias e percepção de esforço em indivíduos com bronquiectasia não fibrocística. Métodos: Estudo transversal com 72 participantes não dependentes de oxigênio (28 homens; média de idade: 48,3 ± 14,5 anos; média do VEF1: 54,1 ± 23,4% do previsto). Os participantes foram submetidos ao teste de exercício cardiopulmonar (TECP) incremental em esteira e ao constant work-rate exercise testing (CWRET, teste de exercício com carga constante) em esteira, com intervalo de 1 h. Em outra visita, foram submetidos ao incremental shuttle walk test (ISWT, teste de caminhada incremental) e ao endurance shuttle walk test (ESWT, teste de caminhada de resistência), com intervalo de 1 h. A definição de dessaturação foi uma redução da SpO2 ≥ 4% do repouso ao pico do exercício. Resultados: O TECP e o ISWT resultaram em dessaturação de magnitude comparável (−7,7 ± 6,3% vs. −6,6 ± 5,6%; p = 0,10), assim como o fizeram o CWRET e o ESWT (−6,8 ± 5,8% vs. −7,2 ± 6,3%; p = 0,50). Houve concordância entre o TECP e o ISWT quanto ao número de participantes que apresentaram e não apresentaram dessaturação, respectivamente (42 e 14; p < 0,01), bem como entre o CWRET e o ESWT (39 e 16; p < 0,01). A magnitude da dessaturação foi semelhante nos participantes que atingiram ≥ 85% da FC máxima prevista ou não. Conclusões: Os testes de exercício de campo apresentaram boa precisão para detectar dessaturação. Os testes de campo podem ser uma alternativa aos testes de laboratório quando o objetivo é investigar a dessaturação durante o exercício em indivíduos com bronquiectasia.

Clinical, laboratory, and functional characteristics of asthma-COPD overlap in patients with a primary diagnosis of COPD / Características clínicas, laboratoriais e funcionais da sobreposição asma-DPOC em pacientes previamente diagnosticados com DPOC

ABSTRACT Objective: To evaluate the frequency of asthma-COPD overlap (ACO) in patients with COPD and to compare, from a clinical, laboratory, and functional point of view, patients with and without ACO, according to different diagnostic criteria. Methods: The participants underwent evaluation by a pulmonologist, together with spirometry and blood tests. All of the patients were instructed to record their PEF twice a day. The diagnosis of ACO was based on the Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar (PLATINO, Latin American Project for the Investigation of Obstructive Lung Disease) criteria, the American Thoracic Society (ATS) Roundtable criteria, and the Spanish criteria. We investigated patient histories of exacerbations and hospitalizations, after which we applied the COPD Assessment Test and the modified Medical Research Council scale, to classify risk and symptoms in accordance with the GOLD criteria. Results: Of the 51 COPD patients, 14 (27.5%), 8 (12.2%), and 18 (40.0) were diagnosed with ACO on the basis of the PLATINO, ATS Roundtable, and Spanish criteria, respectively. The values for pre-bronchodilator FVC, post-bronchodilator FVC, and pre-bronchodilator FEV1 were significantly lower among the patients with ACO than among those with COPD only (1.9 ± 0.4 L vs. 2.4 ± 0.7 L, 2.1 ± 0.5 L vs. 2.5 ± 0.8 L, and 1.0 ± 0.3 L vs. 1.3 ± 0.5 L, respectively). When the Spanish criteria were applied, IgE levels were significantly higher among the patients with ACO than among those with COPD only (363.7 ± 525.9 kU/L vs. 58.2 ± 81.6 kU/L). A history of asthma was more common among the patients with ACO (p < 0.001 for all criteria). Conclusions: In our sample, patients with ACO were more likely to report previous episodes of asthma and had worse lung function than did those with COPD only. The ATS Roundtable criteria appear to be the most judicious, although concordance was greatest between the PLATINO and the Spanish criteria.

RESUMO Objetivo: Avaliar a frequência de asthma-COPD overlap (ACO, sobreposição asma-DPOC) em pacientes com DPOC e comparar, do ponto de vista clínico, laboratorial e funcional, os pacientes com e sem essa sobreposição conforme diferentes critérios diagnósticos. Métodos: Os participantes foram submetidos à avaliação com pneumologista, espirometria e exame sanguíneo, sendo orientados a manter o registro do PFE duas vezes ao dia. O diagnóstico de ACO deu-se através dos critérios Projeto Latino-Americano de Investigação em Obstrução Pulmonar (PLATINO), American Thoracic Society (ATS) Roundtable e Espanhol. Foram investigados os históricos de exacerbações e hospitalizações e aplicados os instrumentos COPD Assessment Test e escala Medical Research Council modificada, utilizados para a classificação de risco e sintomas da GOLD. Resultados: Entre os 51 pacientes com DPOC, 14 (27,5%), 8 (12,2%) e 18 (40,0) foram diagnosticados com ACO segundo os critérios PLATINO, ATS Roundtable e Espanhol, respectivamente. Pacientes com sobreposição significativamente apresentaram pior CVF pré-broncodilatador (1,9 ± 0,4 L vs. 2,4 ± 0,7 L), CVF pós-broncodilatador (2,1 ± 0,5 L vs. 2,5 ± 0,8 L) e VEF1 pré-broncodilatador (1,0 ± 0,3 L vs. 1,3 ± 0,5 L) quando comparados a pacientes com DPOC. Os níveis de IgE foram significativamente mais elevados em pacientes com sobreposição diagnosticados pelo critério Espanhol (363,7 ± 525,9 kU/L vs. 58,2 ± 81,6 kU/L). O histórico de asma foi mais frequente em pacientes com a sobreposição (p < 0,001 para todos os critérios). Conclusões: Nesta amostra, pacientes com ACO relataram asma prévia com maior frequência e possuíam pior função pulmonar quando comparados a pacientes com DPOC. O critério ATS Roundtable aparenta ser o mais criterioso em sua definição, enquanto os critérios PLATINO e Espanhol apresentaram maior concordância entre si.

Relação do tempo de trânsito faríngeo e presença de resíduo com dispneia e função pulmonar na doença pulmonar obstrutiva crônica / Relationship of pharyngeal transition time and presence of residue with dyspnea and lung function in chronic obstructive pulmonary disease

RESUMO Objetivo Relacionar o tempo de trânsito faríngeo e a presença de resíduos com a dispneia e a função pulmonar em indivíduos com Doença Pulmonar Obstrutiva Crônica DPOC. Método Estudo realizado com 19 adultos (11 homens e 8 mulheres) com diagnóstico clínico e espirométrico de DPOC e idade média de 63,8 (±9,3) anos. A coleta de dados foi realizada utilizando o questionário COPD Assessment Test (CAT, Teste de Avaliação da DPOC) a escala de dispneia do Medical Research Council modificada (mMRC) e um manovacuômetro digital, para caracterizar o impacto da doença no indivíduo, a dispneia e a função pulmonar. Os dados referentes ao tempo de trânsito faríngeo e resíduo faríngeo foram coletados por meio de análise das imagens videofluoroscópicas realizada por três juízes cegados. Resultados Não foram encontradas relações significativas entre tempo de trânsito faríngeo (TTF) com função pulmonar (r = -0,71), e entre presença de resíduo faríngeo com a dispneia (r= -0,06). O TTF, quando comparado com a normalidade, apresentou-se aumentado. Conclusão Os indivíduos com DPOC, independente da gravidade da doença, não manifestaram associação entre alterações no TTF e resíduo faríngeo e dispneia e função pulmonar.

ABSTRACT Purpose To relate pharyngeal transit time and the presence of residues with dyspnea and lung function in individuals with Chronic Obstructive Pulmonary Disease COPD. Methods Study conducted with 19 adults (11 men, 8 women) with a clinical and spirometric diagnosis of COPD and a mean age of 63.8 years (SD = 9.3). Data collection was performed using the COPD Assessment Test (CAT) questionnaire, the modified Medical Research Council scale (mMRC) and a digital manovacuometer, to characterize the impact of the disease on the individual, dyspnea and lung function. The data related to pharyngeal transit time and pharyngeal residue were collected through the analysis of videofluoroscopic images performed by three blinded judges. Results No significant relationship was found between pharyngeal transit time (PTT) with lung function (r = -0.71), pharyngeal residue and dyspnea (r = -0.06). PTT, when compared to normality, was increased. Conclusion Individuals with COPD, regardless of the severity of the disease, showed no association between PTT and pharyngeal residue and dyspnea and lung function.

Impact of climate variability on exercise-induced bronchospasm in adolescents living in a semi-arid region / Influência de alterações climáticas sobre a ocorrência do broncoespasmo induzido por exercício em adolescentes de uma região semiárida

ABSTRACT Objective: To examine the impact of climate variability on the occurrence of exercise-induced bronchospasm in the rainy and dry seasons of a Brazilian semi-arid region. Methods: This sample comprised 82 adolescents aged 15 to 18 years, who were submitted to exercise-induced bronchospasm assessment on a treadmill and outdoors, during the rainy and the dry season. Anthropometric variables, sexual maturity and forced expiratory volume in the first second were analyzed. Air temperature and humidity, decline in forced expiratory volume in the first second (%) and frequency of bronchospasm were compared between seasons using the independent Student's t test, the Wilcoxon and McNemar tests, respectively. The level of significance was set at p<0.05. Results: The mean age was 15.65±0.82 years. Air temperature, air humidity and decline in forced expiratory volume in the first second (%) differed between seasons, with higher air temperature and humidity in the rainy season (29.6ºC±0.1 and 70.8%±0.6 versus 28.5ºC±0.2 and 48.5%±0.6; p<0.05). The decline in forced expiratory volume in the first second (%) was greater in the dry season (9.43%±9.97 versus 12.94%±15.65; p<0.05). The frequency of bronchospasm did not differ between seasons. Conclusion: The dry season had a negative impact on forced expiratory volume in the first second in adolescents, with greater decrease detected during this period. Findings of this study suggested bronchospasm tends to be more severe under low humidity conditions.

RESUMO Objetivo: Verificar a influência das alterações climáticas sobre o broncoespasmo induzido por exercício, nos períodos chuvoso e seco de uma região do semiárido brasileiro. Métodos: Foram submetidos à avaliação do broncoespasmo em esteira ergométrica, em ambiente externo, nos períodos chuvoso e seco, 82 adolescentes, com idades de 15 a 18 anos. Foram avaliadas as variáveis antropométricas, a maturação sexual e o volume expiratório forçado no primeiro segundo. Para comparação da temperatura e umidade, queda do volume expiratório forçado no primeiro segundo (%) e frequência do broncoespasmo entre os períodos, foram utilizados o teste t de Student independente, o teste de Wilcoxon e o teste de McNemar, respectivamente. O nível de significância adotado foi p<0,05. Resultados: A média de idade foi 15,65±0,82 anos. A temperatura, a umidade e a queda do volume expiratório forçado no primeiro segundo (%) diferiram entre os períodos, com valores de temperatura e umidade maiores no período chuvoso (29,6ºC±0,1 e 70,8%±0,6 versus 28,5ºC±0,2 e 48,4%±0,6; p<0,05). A queda do volume expiratório forçado no primeiro segundo (%) foi maior no período seco (9,43%±9,97 versus 12,94%±15,65; p<0,05), e não foi encontrada diferença da frequência do broncoespasmo entre os períodos. Conclusão: O período seco influenciou negativamente no volume expiratório forçado no primeiro segundo de adolescentes, observando maior percentual de queda dessa variável nesse período. De acordo com os achados, propõe-se uma maior gravidade do broncoespasmo induzido por exercício em condições de baixa umidade.

Spirometry for the diagnosis of airway obstruction in patients with risk factors for COPD: the GOLD and lower limit of normal criteria / Espirometria para o diagnóstico de obstrução das vias aéreas em pacientes com fatores de risco para DPOC: os critérios GOLD e limite inferior da normalidade

ABSTRACT Objective: The identification of persistent airway obstruction is key to making a diagnosis of COPD. The GOLD guidelines suggest a fixed criterion-a post-bronchodilator FEV1/FVC ratio < 70%-to define obstruction, although other guidelines suggest that a post-bronchodilator FEV1/FVC ratio < the lower limit of normal (LLN) is the most accurate criterion. Methods: This was an observational study of individuals ≥ 40 years of age with risk factors for COPD who were referred to our pulmonary function laboratory for spirometry. Respiratory symptoms were also recorded. We calculated the prevalence of airway obstruction and of no airway obstruction, according to the GOLD criterion (GOLD+ and GOLD−, respectively) and according to the LLN criterion (LLN+ and LLN−, respectively). We also evaluated the level of agreement between the two criteria. Results: A total of 241 individuals were included. Airway obstruction was identified according to the GOLD criterion in 42 individuals (17.4%) and according to the LLN criterion in 23 (9.5%). The overall level of agreement between the two criteria was good (k = 0.67; 95% CI: 0.52-0.81), although it was lower among the individuals ≥ 70 years of age (k = 0.42; 95% CI: 0.12-0.72). The proportion of obese individuals was lower in the GOLD+/LLN+ category than in the GOLD+/LLN− category (p = 0.03), as was the median DLCO (p = 0.04). Conclusions: The use of the GOLD criterion appears to be associated with a higher prevalence of COPD. The agreement between the GOLD and LLN criteria also appears to be good, albeit weaker in older individuals. The use of different criteria to define airway obstruction seems to identify individuals with different characteristics. It is essential to understand the clinical meaning of discordance between such criteria. Until more data are available, we recommend a holistic, individualized approach to, as well as close follow-up of, patients with discordant results for airway obstruction.

RESUMO Objetivo: A identificação de obstrução persistente das vias aéreas é fundamental para o diagnóstico de DPOC. As diretrizes da GOLD sugerem um critério fixo - relação VEF1/CVF pós-broncodilatador < 70% - para definir obstrução, embora outras diretrizes sugiram que a relação VEF1/CVF pós-broncodilatador < o limite inferior da normalidade (LIN) é o critério mais preciso. Métodos: Estudo observacional com indivíduos ≥ 40 anos de idade com fatores de risco para DPOC encaminhados ao nosso laboratório de função pulmonar para espirometria. Também foram registrados sintomas respiratórios. Calculamos a prevalência de obstrução e de ausência de obstrução das vias aéreas segundo o critério GOLD (GOLD+ e GOLD−, respectivamente) e segundo o critério LIN (LIN+ e LIN−, respectivamente). Avaliamos também o grau de concordância entre os dois critérios. Resultados: Foram incluídos 241 indivíduos. Obstrução das vias aéreas foi identificada segundo o critério GOLD em 42 indivíduos (17,4%) e segundo o critério LIN em 23 (9,5%). A concordância global entre os dois critérios foi boa (k = 0,67; IC95%: 0,52-0,81), embora tenha sido menor entre os indivíduos ≥ 70 anos de idade (k = 0,42; IC95%: 0,12-0,72). A proporção de obesos foi menor na categoria GOLD+/LIN+ do que na categoria GOLD+/LIN− (p = 0,03), assim como a mediana de DLCO (p = 0,04). Conclusões: A utilização do critério GOLD parece estar associada a uma maior prevalência de DPOC. A concordância entre os critérios GOLD e LIN também parece ser boa, embora seja mais fraca em indivíduos mais velhos. A utilização de diferentes critérios para definir obstrução das vias aéreas parece identificar indivíduos com diferentes características. É essencial compreender o significado clínico da discordância entre esses critérios. Até que mais dados estejam disponíveis, recomendamos uma abordagem holística e individualizada e também um acompanhamento cuidadoso dos pacientes com resultados discordantes para obstrução das vias aéreas.