ABSTRACT Objective: To evaluate pulmonary function and functional capacity in children and adolescents with sickle cell disease. Methods: This was a cross-sectional study involving 70 children and adolescents (8-15 years of age) with sickle cell disease who underwent pulmonary function tests (spirometry) and functional capacity testing (six-minute walk test). The results of the pulmonary function tests were compared with variables related to the severity of sickle cell disease and history of asthma and of acute chest syndrome. Results: Of the 64 patients who underwent spirometry, 15 (23.4%) showed abnormal results: restrictive lung disease, in 8 (12.5%); and obstructive lung disease, in 7 (10.9%). Of the 69 patients who underwent the six-minute walk test, 18 (26.1%) showed abnormal results regarding the six-minute walk distance as a percentage of the predicted value for age, and there was a ≥ 3% decrease in SpO 2 in 36 patients (52.2%). Abnormal pulmonary function was not significantly associated with any of the other variables studied, except for hypoxemia and restrictive lung disease. Conclusions: In this sample of children and adolescents with sickle cell disease, there was a significant prevalence of abnormal pulmonary function. The high prevalence of respiratory disorders suggests the need for a closer look at the lung function of this population, in childhood and thereafter
