Prolonged-release pirfenidone in patients with pulmonary fibrosis as a phenotype of post-acute sequelae of COVID-19 pneumonia. Safety and efficacy.

INTRODUCTION: One of the major concerns with post-acute sequelae of COVID-19 (PASC) is the development of pulmonary fibrosis, for which no approved pharmacological treatment exists. Therefore, the primary aim of this open-label study was to evaluate the safety and the potential clinical efficacy of a prolonged-release pirfenidone formulation (PR-PFD) in patients having PASC-pulmonary fibrosis. METHODS: Patients with PASC-pulmonary fibrosis received PR-PFD 1800 mg/day (1200 mg in the morning after breakfast and 600 mg in the evening after dinner) for three months. Blood samples were taken to confirm the pharmacokinetics of PR-PFD, and adverse events (AEs) were evaluated monthly using a short questionnaire. Symptoms, dyspnea, and pulmonary function tests (spirometry, diffusing capacity for carbon monoxide, plethysmography, and 6-min walk test [6MWT]) were evaluated at baseline, and one and three months after having started the PR-PFD treatment. RESULTS: Seventy subjects with mild to moderate lung restriction were included. The most common AEs were diarrhea (23%), heartburn (23%), and headache (16%), for which no modifications in the drug study were needed. Two patients died within the first 30 days of enrolment, and three opted not to continue the study, events which were not associate with PR-PFD. Pulmonary function testing, 6MWT, dyspnea, symptoms, and CT scan significantly improved after three months of treatment with PR-PFD. CONCLUSION: In patients with PASC pulmonary fibrosis, three months' treatment with PR-PFD was safe and showed therapeutic efficacy. Still, it remains to be seen whether the pulmonary fibrotic process remains stable, becomes progressive or will improve.

Household air pollution and COPD: cause and effect or confounding by other aspects of poverty?

SETTING: Household air pollution (HAP) and chronic obstructive pulmonary disease (COPD) are both major public health problems, reported to cause around 4 million and 3 million deaths every year, respectively. The great majority of these deaths, as well as the burden of disease during life is felt by people in low- and middle-income countries (LMICs).OBJECTIVE and DESIGN: The extent to which HAP causes COPD is controversial; we therefore undertook this review to offer a viewpoint on this from the Global Initiative for COPD (GOLD).RESULTS: We find that while COPD is well-defined in many studies on COPD and HAP, there are major limitations to the definition and measurement of HAP. It is thus difficult to disentangle HAP from other features of poverty that are themselves associated with COPD. We identify other limitations to primary research studies, including the use of cross-sectional designs that limit causal inference.CONCLUSION: There is substantial preventable morbidity and mortality associated with HAP, COPD and poverty, separately and together. Although it may not be possible to define clear causal links between HAP and COPD, there is a clear urgency to reduce the avoidable burden of disease these inflict on the world´s poor.

Crisis asmática grave asociada con infección viral / Severe asthmatic crisis related to viral infection

Resumen ANTECEDENTES: 50% de las crisis asmáticas son desencadenadas por infecciones virales, su relación con parámetros clínicos no se ha descrito en los adultos. OBJETIVO: determinar la prevalencia de crisis asmáticas de acuerdo con el espectro viral y su asociación con características clínicas y mecánica respiratoria. MATERIAL Y MÉTODO: estudio clínico, prospectivo y observacional en el que se incluyeron pacientes con crisis asmática grave del 1 de diciembre de 2010 al 31 de diciembre de 2011. Se excluyeron los pacientes con sospecha de infección bacteriana. Se aplicó cuestionario de síntomas, se determinó panel viral por hisopado nasal, espirometría y estudios de laboratorio. Se obtuvo el consentimiento informado de los participantes. RESULTADOS: se incluyeron en el estudio 100 pacientes. La edad promedio fue de 39±14 años, IMC 27±4 kg/m2, escala de Borg 6.2±1.2, escala mMRC 2.6±0.6, tiempo de los síntomas 7±7 días, FEV1 de 42±14%, oximetría de pulso 88±3% y estancia de 4.5±1.7 días. El 47% de los pacientes tenía rinitis alérgica. Se aisló virus en 36% (rinovirus 15% y coronavirus 6%). Al comparar la causa viral vs no viral, se observó que los pacientes eran menores en el primer grupo (36±13 vs 43±17 años, p=0.014); no hubo diferencia entre grado de obstrucción y síntomas. A mayor severidad del asma hubo más aislamientos de virus. CONCLUSIÓN: las crisis asmáticas asociadas con virus respiratorios tienen comportamiento clínico similar al de las no asociadas. En los pacientes con menor edad y con comportamiento más grave se aíslan virus con más frecuencia.

Abstract BACKGROUND: 50% of asthma attacks are triggered by viral in fections; its relationship with clinical parameters has not been described in adults. OBJECTIVE: To determine the prevalence of asthma attacks according to viral spectrum and its association with clinical features and respiratory mechanics. MATERIAL AND METHOD: A clinical, prospective and observational study with patients with severe asthma attended from December 1st 2010 to December 31st 2011. We excluded patients with suspected bacterial infection. Symptom questionnaire was applied, it was determined by nasal swab viral panel, spirometry and laboratory studies. Informed consent was obtained. RESULTS: One hundred patients were included. Mean age was 39±14 years, BMI 27±4 kg/m2, Borg 6.2±1.2, mMRC 2.6±0.6, length of symptoms 7±7 days and FEV1 of 42±14%, pulse oximetry 88±3% and stay 4.5±1.7 days; 47% of patients had allergic rhinitis. Virus was isolated in 36% (15% rhinovirus and 6% coronavirus). Comparing the non-viral vs viral etiology, patients were younger (36±13 vs 43±17 years, p=0.014) there was no difference between the degree of obstruction and symptoms. A greater severity of asthma was related to more isolation. CONCLUSION: Asthma attacks associated with respiratory viruses have similar clinical behavior to not associated ones. In younger patients with more severe behavior virus are isolated more frequently.

Identification of circulating miRNAs profiles that distinguish malignant pleural mesothelioma from lung adenocarcinoma.

Accurate diagnosis of malignant pleura mesothelioma (MPM) is challenging. Differential diagnosis of MPM versus lung adenocarcinoma (AD) is particularly difficult, yet clinically important since the two neoplasias call for different treatment approaches. Circulating miRNA-profiling to identify miRNAs that can be used to distinguish MPM from AD has not been reported. We conducted a wide screening study of miRNA profiles in serum pools of MPM patients (N = 11), AD patients (N = 36), and healthy subjects (N = 45) to identify non-invasive biomarkers for differential diagnosis of MPM and AD, using deep sequencing. Sequencing detected up to 300 known miRNAs and up to 25 novel miRNAs species in the serum samples. Among known miRNAs, 7 were upregulated in MPM and 12 were upregulated in AD compared to healthy controls. Of these, eight were distinctive for AD and three were unique for MPM. Direct comparison of the miRNA profiles for MPM and AD revealed differences in miRNA levels that could be useful for differential diagnosis. No differentially expressed novel miRNAs were found. Further bioinformatics analysis indicated that three upregulated miRNAs in MPM are associated with the p38 pathway. There are unique alterations in serum miRNAs in MPM and AD compared to healthy controls, as well as differences between MPM and AD profiles. Differing miRNA levels between MPM and AD may be useful for differential diagnosis. A potential association to p38 pathway of three upregulated miRNAs in MPM was revealed.

[Descriptors of breathlessness in Mexican Spanish]. / El lenguaje de la disnea. Una visión desde el español de México.

OBJECTIVE: Breathlessness is the most common symptom of cardiovascular or pulmonary disease. The term encompasses a wide range of descriptors used by patients, however. Identifying those descriptors can be useful for analyzing symptoms and understanding how they arise. The aim of this study was to characterize the descriptors of breathlessness used in Mexican Spanish and to consider their association with various states of respiratory distress and cardiovascular or pulmonary disease. MATERIAL AND METHODS: A questionnaire was based on 21 descriptors of breathlessness, some of which had no equivalents in English. The subjects included 15 healthy individuals during a cardiopulmonary stress test, 13 healthy subjects after a carbon dioxide rebreathing procedure, and 10 healthy women during pregnancy. We also included 16 patients with confirmed heart disease in stable condition, 15 patients during exacerbation of asthma, 20 with stable chronic obstructive pulmonary disease, and 15 with diffuse interstitial lung disease also in stable condition. Descriptors of breathlessness were then grouped based on the results of cluster analysis. RESULTS: Seven clusters of phrasal descriptors were identified as possibly representative of types of dyspnea. These clusters of descriptors were categorized as follows: agitation, suffocation, smothering, inhalation, exhalation, panting, and rapidity. Associations between types of dyspnea and the groups of participants were identified based on how frequently they used the terms. CONCLUSIONS: At least 7 clusters or groups of descriptors of breathlessness were identified as equivalent to 7 types of dyspnea; some items have no equivalent in English. Healthy subjects with respiratory distress or certain groups of patients with cardiovascular or pulmonary disease are associated with certain types of dyspnea.

El lenguaje de la disnea. Una visión desde el español de México / Descriptors of breathlessness in Mexican spanish

Objetivo: La disnea es el síntoma más frecuente en la enfermedad cardiovascular o pulmonar. Sin embargo, el término engloba un número variado de descriptores que suelen usar o identificar los pacientes. Identificar estos descriptores puede ser de utilidad semiológica y para la compresión de su patogenia. El objetivo del presente estudio ha sido caracterizar los descriptores de disnea utilizados en español mexicano y su asociación con diferentes estados de estrés respiratorio o enfermedad cardiovascular o pulmonar. Material y métodos: Se estructuró un cuestionario de disnea basado en 21 descriptores, algunos sin equivalentes en idioma inglés. Se estudió a 15 sujetos sanos durante una prueba de ejercicio cardiopulmonar, a 13 durante una prueba de hipercapnia y a 10 mujeres embarazadas. Asimismo, se incluyó a 16 pacientes estables con cardiopatía demostrada, a 15 pacientes con crisis asmática, a 20 con enfermedad pulmonar obstructiva crónica estable y a 15 con neumopatía intersticial difusa también estable. La agrupación de los diferentes descriptores de disnea se determinó por análisis de conglomerados. Resultados: Se encontraron 7 conglomerados o asociaciones de descriptores que pueden interpretarse como tipos de disnea. Estos grupos de frases descriptivas se pueden englobar bajo los siguientes conceptos: agitación, asfixia, sofocación, inhalación exhalación, jadeo y rapidez. Se encontraron algunas asociaciones entre tipos de disnea y los grupos estudiados sobre la base de la frecuencia de uso de los términos. Conclusiones: Existen al menos 7 conglomerados o asociaciones de descriptores de disnea que equivalen a 7 tipos de disnea; algunos de los descriptores carecen de equivalente en inglés. Los sujetos sanos en estrés respiratorio o algunos grupos de pacientes con enfermedad cardiovascular o pulmonar se asociaron a tipos específicos de disnea

Objective: Breathlessness is the most common symptom of cardiovascular or pulmonary disease. The term encompasses a wide range of descriptors used by patients, however. Identifying those descriptors can be useful for analyzing symptoms and understanding how they arise. The aim of this study was to characterize the descriptors of breathlessness used in Mexican Spanish and to consider their association with various states of respiratory distress and cardiovascular or pulmonary disease. Material and methods: A questionnaire was based on 21 descriptors of breathlessness, some of which had no equivalents in English. The subjects included 15 healthy individuals during a cardiopulmonary stress test, 13 healthy subjects after a carbon dioxide rebreathing procedure, and 10 healthy women during pregnancy. We also included 16 patients with confirmed heart disease in stable condition, 15 patients during exacerbation of asthma, 20 with stable chronic obstructive pulmonary disease, and 15 with diffuse interstitial lung disease also in stable condition. Descriptors of breathlessness were then grouped based on the results of cluster analysis. Results: Seven clusters of phrasal descriptors were identified as possibly representative of types of dyspnea. These clusters of descriptors were categorized as follows: agitation, suffocation, smothering, inhalation, exhalation, panting, and rapidity. Associations between types of dyspnea and the groups of participants were identified based on how frequently they used the terms. Conclusions: At least 7 clusters or groups of descriptors of breathlessness were identified as equivalent to 7 types of dyspnea; some items have no equivalent in English. Healthy subjects with respiratory distress or certain groups of patients with cardiovascular or pulmonary disease are associated with certain types of dyspnea

[Severity of dyspnea during exercise: similarities and differences between patients with COPD or pulmonary fibrosis]. / Similitudes y diferencias en el grado de disnea durante el ejercicio en pacientes con EPOC y fibrosis pulmonar.

To understand the mechanisms leading to dyspnea during exercise and to identify possible predictive factors, we compared dyspnea at rest (baseline)and during exercise in 27 patients with chronic obstructive pulmonary disease (COPD) and 39 pulmonary fibrosis (PF) patients. We also compared spirometry and blood gases at rest and after exercise,which consisted of a 12-minute walking test (12 WT). Heart rate and oxygen saturation (SaO2) were recorded every two minutes during the 12 WT. Distance walked was also recorded. Although dyspnea changed during the 12 WT in both groups (p < 0.001),the maximum level of dyspnea reached in the two groups was not statistically different. COPD patients walked farther than did PF patients (782 +/- 182 m vs. 618 +/- 225 m, respectively;p = 0.002) and paused less often during the 12 WT than did PF patients(0.18 +/- 0.55 vs. 0.82 +/- 1.55, respectively; p <0.05). After adjusting for diagnosis, age, sex, baseline dyspnea,distance walked and pauses during the 12 WT, we found that only SaO2 was significantly related to severity of dyspnea during exercise. We conclude that there are important differences in degree of dyspnea experienced during exercise by COPD and PF patients and that SaO2 is the only variable that predicts severity of dyspnea.

Similitudes y diferencias en el grado de disnea durante el ejercicio en pacientes con EPOC y fibrosis pulmonar / Severity of dyspnea during exercise: similarities and differences between patients with COPD or pulmonary fibrosis

Con el objeto de entender los mecanismos de la disnea durante el ejercicio y posibles factores de predicción, evaluamos la disnea basal y en ejercicio en 27 pacientes con enfermedad pulmonar obstructiva crónica (EPOC) y 39 con fibrosis pulmonar. Además, se realizó una espirometría, una medición de gases arteriales en reposo y una caminata de 12 min (PC12). Durante la PC12 se midió la frecuencia cardíaca, la saturación de oxígeno (SaO2) cada 2 min y la distancia recorrida. Aunque hubo cambios en la disnea a lo largo de la prueba de ejercicio en ambos grupos (p < 0,001), el grado máximo de disnea no fue estadísticamente significativo entre los grupos estudiados. Los pacientes con EPOC recorrieron distancias mayores que los individuos con fibrosis pulmonar (782 ñ 182 y 618 ñ 225 m, respectivamente; p = 0,002) y evidenciaron un menor número de pausas durante la PC12 que los sujetos con fibrosis pulmonar (0,18 ñ 0,55 frente a 0,82 ñ 1,55, respectivamente; p < 0,05). Después de ajustar por diagnóstico, edad, sexo, disnea basal, distancia total recorrida y pausas en la PC12, sólo la SaO2 se asoció significativamente con el grado de disnea durante el ejercicio. En resumen, hay diferencias importantes en el grado de disnea durante el ejercicio entre pacientes con EPOC y fibrosis pulmonar, y la SaO2 es la única variable capaz de predecirla. (AU)

[Hypersensitivity pneumonitis in Mexico City]. / Neumonitis por hipersensibilidad en la ciudad de México.

OBJECTIVE: To investigate the association between the urban area of origin of patients and the prevalence of hypersensitivity pneumonitis (HP), induced by avian antigens. MATERIAL AND METHODS: A case-control study was conducted in 1999 at the National Institute of Respiratory Diseases (NIRD). Cases were 109 consecutive HP patients and controls were 184 patients: 39 with idiopathic pulmonary fibrosis (IPF), 63 with pulmonary tuberculosis (PTB), and 82 with asthma. Mexico City and surrounding counties (SC) were divided into 5 geographical areas: 1) Downtown; 2) North-East (NE); 3) South-East (SE); 4) North-West (NW) and 5) South-West (SW). Statistical analysis consisted of calculation of disease prevalence by urban area; associations were assessed with odds ratios and 95% confidence intervals. Multivariate analysis with multiple logistic regression was performed to adjust for age, gender and socioeconomic level. RESULTS: Eighty HP cases were located in the NE southernmost and SE northernmost areas of Mexico City (48 and 32, respectively) (OR = 3.86; 95% CI 2.17-6.96). Thirty-six controls with asthma came from the SW area, (where NIRD is located) (p < 0.05), and four from SC. Controls with PTB and IPF were scattered throughout the study area. CONCLUSIONS: The NE southernmost and SE northernmost areas were associated with HP. The cause of HP may not be geographical; a garbage dump used to be located in this area, suggesting that exposure to organic particles might contribute to the development of HP in susceptible individuals.

[Smoking among Mexican physician. A comparative analysis with smokers who are not physicians]. / Tabaquismo en médicos mexicanos. Un análisis comparativo con fumadores que no son médicos.

OBJECTIVES: To determine prevalence, addiction knowledge and attitude on tobacco smoking in a group of smoking physicians (MF) and to compare these variables with smoking non-physicians (FNM) and non-smoking physicians (MNF) from the National Institutes of Health in Mexico (Insalud). MATERIAL AND METHODS: The results of a questionnaire among the three groups were compared. RESULTS: The prevalence of MF (22%) was significantly lower than in FNM (28%), (OR = 0.72, CI = 0.61-0.85). No significant differences regarding addiction and attitudes were found between them. The MNF had better knowledge and attitudes and agreed that their Institute should be a non-smoking area. CONCLUSION: Prevalence of smoking is lower among physicians than among FNM and the similarities between them suggest that addiction can provoke them and that a program for tobacco control is required.

Prevalence of cigarette smoking among employees of the Mexican National Institutes of Health.

OBJECTIVE: To determine the prevalence of cigarette smoking at the National Institutes of Health in Mexico (NIHM). MATERIAL AND METHODS: A survey was performed among workers who voluntarily answered a questionnaire. Smokers were identified with two specific questions, and type of employment was classified as physicians, administrative staff, investigators and support personnel. RESULTS: Total prevalence smoking was 28% (of 4,422 answered questionnaires). It was significantly higher among females, among administrative staff, and common-law and separated workers. It was significantly higher at the Mexican Institute of Psychiatry than at the remaining Institutes, even after adjusting for confounding. The prevalence was also higher among physicians from the same Institute. Of the smokers, 46% do so in their work areas and 78% of them would like to quit. CONCLUSIONS: The prevalence of smokers at the NIHM is as high as in the general population and a broad educational program for tobacco control and prevention is needed.

Utility of a provocation test for diagnosis of chronic pigeon Breeder's disease.

Chronic hypersensitivity pneumonitis (CHP) can be difficult to differentiate from other interstitial lung diseases (ILD). To determine the diagnostic usefulness of a provocation test (PT), 17 patients with CHP induced by avian antigens, 17 with other ILD, and five healthy control subjects were challenged with pigeon serum. After PT, an increase in body temperature (BT) and a decrease in FVC, PaO2 and SaO2% were observed in all patients with CHP and in three with ILD. No reaction was noticed in healthy subjects. ROC curves showed that for FVC the best cut point was a drop of 16% displaying sensitivity (S): 76%, specificity (SP): 81%, positive predictive value (PPV): 81%, and negative predictive value (NPV): 83%. For a drop of 3 mm Hg in PaO2 or 3% SaO2, S was 88% for both, SP was 82 and 86%, PPV was 81 and 82%, and NPV was 82 and 86%, respectively. An increase of BT > 0.5(o) C showed S, 100%; SP, 82%; PPV, 100%; NPV, 86%. A univariate regression analysis confirmed that changes in BT and FVC are predicting values of CHP: RR, 82.5 (CI, 10.43 to 651.76) and 1.21 (CI, 1.06 to 1.36). There were no challenge test complications. These findings suggest that PT is a useful tool for diagnosis of CHP.

Salmeterol reduces dyspnea and improves lung function in patients with COPD.

STUDY OBJECTIVE: To investigate the short-term effects of inhaled salmeterol on the perception of dyspnea and lung function in patients with COPD. DESIGN: Double-blind, crossover, randomized trial comparing inhaled salmeterol and inhaled placebo over 4 h. SETTING: Pulmonary function laboratory at university medical center. PATIENTS: Sixteen patients with symptomatic COPD and at least 200-mL increase in FEV1 after inhalation of two puffs (180 microg) of albuterol. INTERVENTIONS: Visit 1 was used for familiarization. At visits 2 and 3 (2 to 3 days apart), patients inhaled either two puffs of salmeterol (42 microg) or placebo. MEASUREMENTS AND RESULTS: Lung function and dyspnea were measured at 0.5, 2, and 4 h after inhalation of the study medication. Dyspnea was measured by the -5 to +5 category scale at rest and by the 0 to 10 category-ratio scale while breathing through inspiratory resistances of 5, 15, and 30 cm H20/L/s. Age was 66+/-8 years (mean+/-SD). FEV1 was 0.97+/-0.331 (51+/-13% predicted). There were significantly higher values for FEV1 and FVC (at all time periods) and lower values for functional residual capacity (at all time periods) and residual volume (at 4 h) with salmeterol than with placebo. There were significantly lower dyspnea ratings on the -5 to +5 category scale (p=0.03 at 2 h and p=0.02 at 4 h) and for the mean dyspnea scores during resistive breathing with salmeterol compared with placebo (p=0.002). CONCLUSIONS: Inhaled salmeterol reduced dyspnea, increased airflow, and reduced hyperinflation over 4 h in patients with symptomatic COPD.

Effect of exercise training on dyspnea measures in patients with chronic obstructive pulmonary disease.

PURPOSE: This study investigated the possible mechanisms for the expected improvement in dyspnea with pulmonary rehabilitation. METHODS: Lung function, clinical ratings of dyspnea, and exercise responses were studied in 44 patients with chronic obstructive pulmonary disease who participated in an outpatient program consisting of 1.5 hours per week of supervised education, breathing training, and upper/lower extremity exercise. RESULTS: After rehabilitation, there were significant increases in forced expiratory volume in 1 second (FEV1, 7%; P = .02), maximal inspiratory mouth pressure (PImax, 17%; P < .001), and the transition dyspnea index focal score (3.4; P < .001) and a significant decrease in the slope of dyspnea/power (0.12 versus 0.09; P = .001) during exercise. Patients who demonstrated > or = 0 mL of change in FEV1 or > or = 5 cm H2O of change in PImax exhibited significant decreases in the slopes for dyspnea/power. CONCLUSIONS: After pulmonary rehabilitation, there was a significant improvement in dyspnea. Although there was no evidence of a physiologic training response or enhanced mechanical efficiency, the modest increase in FEV1 and the increase in respiratory muscle strength appeared to contribute to the reduction in dyspnea.

Correlation between pulmonary fibrosis and the lung pressure-volume curve.

The severity of pulmonary fibrosis is the main prognostic factor for survival of patients with interstitial lung diseases (ILD). Unfortunately, lung biopsy, which is the best method to assess fibrosis quantitatively, is done only once during the evolution of the disease. In this study we analyzed the relationship between the degree of fibrosis and the exponential constant k, derived from the lung pressure-volume curve (LPVC) in 33 patients with chronic ILD, 19 with pigeon breeder's disease (PBD), and 14 with idiopathic pulmonary fibrosis (IPF). Pulmonary function tests, including the LPVC, were obtained before biopsy. A semiquantitative histologic assessment of the severity of fibrosis was performed on lung tissues. All patients showed a decrease of total lung capacity, residual volume, compliance, and Pao2. The mean value of the constant k was 0.08 +/- 0.06. When expressed as a percent of normal values, 25 patients exhibited values of k lower than 70% of predicted; of the remaining 8 patients whose values were above 70% of predicted, 7 had PBD and only one IPF. On morphologic analysis, 19 patients displayed more than 50% fibrosis. No significant correlations were found between the extent of the lesion or severity of lung fibrosis and the conventional pulmonary function tests. By contrast, a moderate but significant correlation was found between k and the severity of lung fibrosis (r = -0.38, p < 0.05). These findings show that the shape of the LPVC, represented by the constant k, predicts the degree of lung fibrosis and could be useful in the clinical assessment and follow-up of patients with ILD.

Reversal of digital clubbing after lung transplantation.

Digital clubbing is a common sign in a variety of lung diseases. Although its pathogenesis remains unclear, it is known that the degree of clubbing might vary and even disappear, particularly when the underlying disease is a malignant neoplasm that has been removed. By contrast, because of the short expectancy of life in patients with pulmonary fibrosis, it is unusual to observe regression of clubbing. In this work, we report a case of reversible clubbing after lung transplantation.

[Validation of a visual analog scale to measure dyspnea in patients with diffuse interstitial lung disease]. / Validación de una escala análoga visual para medir disnea en pacientes con enfermedad pulmonar intersticial difusa.

In order to validate a form of measuring dyspnea, a visual analog scale (VAS) was applied to 27 patients with different types of interstitial lung diseases (ILD). The test was done in two days with an interval of one month (dyspnea1 and dyspnea2). Additionally, the forced vital capacity (FVC) was obtained on these occasions (FVC1, FVC2). Nineteen patients with a recent diagnosis of ILD (RD) and eight with a previous diagnosis of ILD (PD) were included. In patients with RD, dyspnea1 correlated with FVC1 (r = -0.66, p < 0.01). A month after the initial treatment with steroids, dyspnea (mean +/- SD) decreased from 38 +/- 25 mm to 17 +/- 19 mm (p < 0.03), while the FVC increased from 1086 +/- 464 mL to 1350 +/- 536 mL (p < 0.05). Likewise, dyspnea2 correlated with FVC2 (r = -0.47, p < 0.05). As expected, patients with PD did not exhibit significant changes in the analysis of dyspnea on the second evaluation. The inter-observer coefficient of variation for the 8 patients with PD was of 5% and 9% for the first and second evaluations respectively, while the intraclass correlation coefficient was 0.92 and 0.91 respectively. The intra-observer coefficient of variation of two different observers was of 15% and 16% respectively, while the intraclass correlation coefficient was 0.69 and 0.62 respectively. These results suggest that the use of a VAS might be useful for the initial evaluation and during the follow-up of patients with ILD.