Functional capacity and quality of life in children and adolescents with sickle cell anemia.

OBJECTIVE: To evaluate the functional and exercise capacity, lung function, quality of life of children and adolescents with sickle cell anemia (SCA HbSS) and to test the reproducibility of functional capacity tests in this population. METHOD: Cross-sectional study with volunteers with SCA Hb-SS (SCAG), aged 6-18 years matched in age and gender to the control group (CG) with healthy individuals. Spirometry, 5-repetition sit-to-stand test (5STS-test), modified shuttle test (MST), and Pediatric Quality of Life Questionnaire (PedsQL) were performed. The reproducibility of 5STS-test and MST was evaluated: RESULTS: Forty eight volunteers of SCAG and 48 of CG were evaluated. Lung function of SCAG (FVC: 92 ± 15% pred.; FEV1 /FVC: 84 ± 8% pred.) was worse than the CG (104 ± 15% pred.; FEV1 /FVC: 90 ± 6% pred.) p < 0.05. SCAG had worse functional capacity registered by distance walked: 576 m (515-672 m) and 5STS-test: 8 s (7.4-8.9 s) compared with the CG who showed distance walked: 1010 m (887-1219 m) and 5STS-test: 7 s (7.0-8.1 s), p < 0.001. SCAG had worse quality of life compared to CG, p < 0.05. The reproducibility of MST (ICC 0.99 (0.98-0.99 IC-95%)) and 5STS-test (ICC 0.80 (0.69-0.88) was considered good, p < 0.001. CONCLUSION: Children and adolescents with sickle cell anemia presented worse capacity to walk or run, and to perform sit-to-stand test when compared with their control peers. Additionally, they have poorer quality of life. The MST and 5STS-test showed good reproducibility to be applied in pediatric individuals with SCA.

Reference equation for maximal voluntary ventilation in children and adolescents.

OBJECTIVES: To develop reference equations of maximal voluntary ventilation (MVV) in children and adolescents, and to test the validity and reproducibility of MVV. STUDY DESIGN: Cross-sectional study. PATIENT-SUBJECT SELECTION: A total of 348 healthy volunteers (6-17 years)-248 for the development of reference equations and 100 to test the validity- were selected. METHODOLOGY: Spirometry and MVV were performed. Volunteers were instructed to breathe quickly and strongly to estimate the MVV. Independent variables tested were age, sex, weight, height, and pulmonary function. RESULTS: All volunteers (50% boys) had a normal pulmonary function. Mean MVV was 66.3 (17.8) L/minute for children and 118.8 (20.0) L/minute for adolescents. The equation developed for children was MVV = 4.865 + (forced expiratory volume in the first second [FEV1] × 16.257) + (peak expiratory flow [PEF] × 7.621); for adolescents was MVV = -25.450 + (FEV1 × 11.591) + (PEF × 6.672) + (sex × 12.179) + (age × 3.613). No significant differences were observed between measured and predicted MVV in children (64.6 [10.3] vs 64.6 [8.5] L/minute; P = .34) or adolescents (111.8 [23.4] vs 113.1 [22.8] L/minute, P = .12). The intraclass correlation coefficient between measured and predicted MVV was 0.95 (0.91-0.97) for children and 0.90 (0.82-0.94) for adolescents. The mean bias of Bland-Altman analysis was -0.8 L/minute for children and -2.7 L/minute for adolescents. CONCLUSIONS: Normative values for MVV were established for children and adolescents, additionally, these equations are reproducible and it can be used to determine the respiratory impairments in the pediatric population.