Evaluation of functional capacity for exercise in children and adolescents with sickle-cell disease through the six-minute walk test.
OBJECTIVE
To evaluate lung functional capacity (FC) for physical exercise in children and adolescents with sickle cell disease (SCD) through the six-minute walk test (6MWT).


METHODS
A cross-sectional prospective study was performed to evaluate the FC of 46 patients with SCD through the 6MWT. The following parameters were assessed: heart rate (HR), respiratory rate (RR), peripheral pulse oxygen saturation (SpO2), peak expiratory flow (PEF), blood pressure (systolic and diastolic), dyspnea, and leg fatigue (modified Borg scale) at rest, in the end of the test, and ten minutes after the 6MWT. The total distance walked was also recorded. For statistical analysis, the parametric variables were analyzed using the paired Student's t-test, analysis of variance (ANOVA), and Bonferroni multiple comparisons, with a significance level set at p ≤ 0.05.


RESULTS
The 46 patients were aged age 9.15±3.06 years, presented baseline Hb of 9.49±1.67g/dL, and walked 480.89±68.70 m. SCD diagnosis was as follows: group 1- HbSS (n=20)/HbSβ(0)-thalassemia (n=3) and group 2 - HbSC (n=20)/HbSβ(+)-thalassemia (n=3). Regarding total distance walked, patients in group 1 walked a shorter distance than patients in group 2 (459.39±57.19 vs. 502.39±73.60 m; p=0.032). There was no statistical difference regarding PEF in the three moments of evaluation. The SpO2 in ambient air and SpO2 with O2 differed between groups 1 and 2 (p<0.001 vs. p=0.002), as well as the RR (p=0.001).


CONCLUSIONS
These patients showed a lower FC for exercise than that predicted for the age range in the literature. Patients diagnosed with HbSS/Sβ0-thalassemia had a lower performance in the test than those with HbSC/Sβ(+)-thalassemia regarding total distance walked, RR, and SpO2 after the 6MWT.
Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
Sandro V
SV
Hostyn
Werther B de
WB
Carvalho
Cíntia
C
Johnston
Josefina A P
JA
Braga
D000293:Adolescent; D000704:Analysis of Variance; D000755:Anemia, Sickle Cell / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D006931:Hyperbaric Oxygenation; D008297:Male; D009752:Nutritional Status; D012129:Respiratory Function Tests; D013647:Task Performance and Analysis; D016138:Walking / Q000502:physiology*; D014938:Work Capacity Evaluation
Acute chest syndrome; Anemia falciforme; Estado nutricional; Exercise; Exercício; Nutritional status; Sickle cell anemia; Síndrome torácica aguda