Performance of a word labeled visual analog scale in determining the degree of dyspnea during exercise-induced bronchoconstriction in children and adolescents with asthma.

OBJECTIVE: There is an indirect relationship between airway obstruction in asthma and the intensity of breathlessness (dyspnea). A word labeled visual analog dyspnea scale with a 0-3 score has been widely used for the assessment of the degree of bronchoconstriction, although the perception of such obstruction varies considerably. The objective of this study was to determine whether children and adolescents are able to perceive acute exercise-induced bronchoconstriction (EIB), as well as to measure the discriminatory power of a word labeled visual analog dyspnea scale in relation to the intensity of the EIB. METHODS: A cross-sectional study involving 134 children and adolescents with asthma and submitted to a six-minute steady-state exercise test on a cycle ergometer. The intensity of dyspnea was determined using a word labeled visual analog dyspnea scale prior to each determination of FEV1. The scale is scored from 0 to 3, with a logical sequence of pictures, ranging from "no symptoms" to "severe dyspnea". Variables were determined at baseline, as well as at 5, 10, and 20 min after the exercise test. The accuracy of the dyspnea scale in identifying the degree of EIB was determined by means of ROC curves for the post-exercise fall in FEV1, using cut-off points of 10%, 20%, 30%, and 40%. RESULTS: Of the patients selected, 111 finished the study, and 52 (46.8%) presented with EIB. The area under the ROC curve increased in direct proportion to increases in the degree of bronchoconstriction. CONCLUSIONS: Among children and adolescents with asthma, the accuracy of this dyspnea scale improves as the post-exercise percentage fall in FEV1 increases. However, the predictive value of the scale is suboptimal when the percentage fall in FEV1 is lower.

Desempenho de uma escala analógica visual legendada na determinação do grau de dispneia durante teste de broncoespasmo induzido por exercício em crianças e adolescentes asmáticos / Performance of a word labeled visual analog scale in determining the degree of dyspnea during exercise-induced bronchoconstriction in children and adolescents with asthma

OBJETIVO: Existe uma relação indireta entre a obstrução das vias aéreas em asma e a intensidade de falta de ar (dispneia). Uma escala visual analógica legendada de dispneia com escore de 0-3 pontos tem sido amplamente utilizada na avaliação da broncoconstrição, embora a percepção de tal obstrução seja muito variável. O objetivo deste estudo foi determinar se crianças e adolescentes são capazes de perceber a broncoconstrição aguda induzida por exercício (BAIE), bem como medir o poder discriminatório de uma escala visual analógica legendada de dispneia em relação à intensidade de BAIE. MÉTODOS: Estudo transversal com 134 crianças e adolescentes asmáticos que foram submetidos a um teste de broncoespasmo induzido por seis minutos de exercício em um cicloergômetro. A intensidade da dispneia foi determinada utilizando-se uma escala visual analógica legendada de dispneia antes de cada determinação de VEF1. A escala tem um escore de 0-3 pontos, com desenhos em uma sequência lógica variando entre "sem sintomas" e "dispneia grave". As variáveis foram determinadas no momento basal, assim como em 5, 10 e 20 minutos após o término do teste de exercício. A acurácia da escala de dispneia em detectar o grau de BAIE foi determinada através de curvas ROC para a queda de VEF1 após o exercício, usando pontos de corte de 10 por cento, 20 por cento, 30 por cento e 40 por cento. RESULTADOS: Dos pacientes selecionados, 111 completaram o estudo, e 52 (46,8 por cento) apresentaram BAIE. A área sob a curva ROC progressivamente aumentou com o aumento do grau de broncoconstrição. CONCLUSÕES: Em crianças e adolescentes asmáticos, a acurácia desta escala de dispneia melhora com o aumento do percentual de queda em VEF1 após o exercício. Entretanto, o valor preditivo da escala é subótimo quando a porcentagem de queda em VEF1é menor.

OBJECTIVE: There is an indirect relationship between airway obstruction in asthma and the intensity of breathlessness (dyspnea). A word labeled visual analog dyspnea scale with a 0-3 score has been widely used for the assessment of the degree of bronchoconstriction, although the perception of such obstruction varies considerably. The objective of this study was to determine whether children and adolescents are able to perceive acute exercise-induced bronchoconstriction (EIB), as well as to measure the discriminatory power of a word labeled visual analog dyspnea scale in relation to the intensity of the EIB. METHODS: A cross-sectional study involving 134 children and adolescents with asthma and submitted to a six-minute steady-state exercise test on a cycle ergometer. The intensity of dyspnea was determined using a word labeled visual analog dyspnea scale prior to each determination of FEV1. The scale is scored from 0 to 3, with a logical sequence of pictures, ranging from "no symptoms" to "severe dyspnea". Variables were determined at baseline, as well as at 5, 10, and 20 min after the exercise test. The accuracy of the dyspnea scale in identifying the degree of EIB was determined by means of ROC curves for the post-exercise fall in FEV1, using cut-off points of 10 percent, 20 percent, 30 percent, and 40 percent. RESULTS: Of the patients selected, 111 finished the study, and 52 (46.8 percent) presented with EIB. The area under the ROC curve increased in direct proportion to increases in the degree of bronchoconstriction. CONCLUSIONS: Among children and adolescents with asthma, the accuracy of this dyspnea scale improves as the post-exercise percentage fall in FEV1 increases. However, the predictive value of the scale is suboptimal when the percentage fall in FEV1 is lower.

Evaluation of diagnostic criteria for severe asthma described in a public health directive regulating the free distribution of medications for the maintenance treatment of asthma.

OBJECTIVE: To evaluate the capacity of the criteria described in Complementary Directive SAS/MS 12, issued on November 12, 2002, to identify patients with severe asthma, describing and comparing clinical, functional and treatment data of such patients. METHODS: This was a nested case-control study using a structured database for adult asthma outpatients. We defined cases as asthma patients who met the inclusion criteria described in the directive, defining controls as those who did not. We collected and compared data related to the following: demographic characteristics; history of asthma; medications in use; comorbidities; history of tobacco use; number of exacerbations within the last 12 months, asthma-related hospitalizations and intensive care unit admissions within the last 12 months; spirometry; and sputum cytology. RESULTS: The case and control groups consisted of 29 and 31 patients, respectively. The number of asthma exacerbations and emergence room visits within the last 12 months, as well as the number of patients that received at least one pulse of oral corticosteroids, was significantly higher in the case group than in the control group. In addition, prebronchodilator FVC was lower among the cases than among the controls. Furthermore, cytology revealed that eosinophil counts were significantly higher in the induced sputum of cases than in that of controls. CONCLUSIONS: The criteria described in the directive are suited to stratifying patients with severe asthma.

Avaliação dos descritores de asma grave em pacientes incluídos na portaria de saúde pública que regulamenta a distribuição gratuita de medicamentos para o tratamento de manutenção da asma / Evaluation of diagnostic criteria for severe asthma described in a public health directive regulating the free distribution of medications for the maintenance treatment of asthma

OBJETIVO: Avaliar a capacidade dos critérios descritos na Portaria Complementar SAS/MS nº12, de 12 de novembro de 2002, em identificar pacientes asmáticos graves, bem como descrever e comparar dados clínicos, funcionais e de tratamento destes pacientes. MÉTODOS: Estudo caso-controle aninhado em um banco de dados estruturado de atendimento ambulatorial de asmáticos. Foram considerados casos os pacientes asmáticos que preencheram os critérios de inclusão determinados na portaria e considerados controles os que não preencheram os mesmos critérios. Foram coletados e comparados dados demográficos; história pregressa da asma; medicamentos em uso; presença de comorbidades; história de tabagismo; presença, no último ano, de exacerbações, de hospitalizações e de admissões em unidades de terapia intensiva devido à asma; e resultados de espirometria e de citologia de escarro. RESULTADOS: Foram incluídos 29 e 31 pacientes, respectivamente, nos grupos caso e controle. O grupo caso apresentou maior número de exacerbações e maior número de visitas ao pronto-socorro no último ano, maior porcentagem de pacientes que receberam pelo menos um pulso de corticosteroide oral, assim como menores valores de CVF pré-broncodilatador em relação ao grupo controle. O grupo caso também apresentou um aumento significante de eosinófilos na citologia do escarro induzido. CONCLUSÕES: Os critérios de inclusão descritos na portaria são adequados para estratificar pacientes com asma grave.

OBJECTIVE: To evaluate the capacity of the criteria described in Complementary Directive SAS/MS 12, issued on November 12, 2002, to identify patients with severe asthma, describing and comparing clinical, functional and treatment data of such patients. METHODS: This was a nested case-control study using a structured database for adult asthma outpatients. We defined cases as asthma patients who met the inclusion criteria described in the directive, defining controls as those who did not. We collected and compared data related to the following: demographic characteristics; history of asthma; medications in use; comorbidities; history of tobacco use; number of exacerbations within the last 12 months, asthma-related hospitalizations and intensive care unit admissions within the last 12 months; spirometry; and sputum cytology. RESULTS: The case and control groups consisted of 29 and 31 patients, respectively. The number of asthma exacerbations and emergence room visits within the last 12 months, as well as the number of patients that received at least one pulse of oral corticosteroids, was significantly higher in the case group than in the control group. In addition, prebronchodilator FVC was lower among the cases than among the controls. Furthermore, cytology revealed that eosinophil counts were significantly higher in the induced sputum of cases than in that of controls. CONCLUSIONS: The criteria described in the directive are suited to stratifying patients with severe asthma.