Functional Performance in the Modified Shuttle Test in Children and Adolescents With Cystic Fibrosis

Abstract

Objective: To evaluate factors associated with the performance of children and adolescents with cystic fibrosis (CF) in the Modified Shuttle Test (MST) and compare it with healthy children and adolescents. Methods: This is a cross-sectional study, with children and adolescents divided into two groups: cystic fibrosis (CFG) and control (CG). Variables evaluated in the MST: walking distance, test level, heart rate variation (∆Hr), post-test mean arterial pressure (MAP Pt) and peripheral oxygen saturation variation (∆SPO2). Statistical analysis included Mann Whitney and Spearman coefficient tests, being significant p<0.05. Results: Sixty individuals aged 6-16 years old were evaluated. Anthropometric data was similar between groups. Differences between groups were shown for: baseline heart rate (BHr), peak heart rate (PHr), ∆Hr, recovery heart rate (RHr), post-test respiratory rate (PtBr), saturation variables, peripheral oxygen level (SpO2B) and level test. The ∆Hr and MAP Pt had a moderate positive correlation with distance and level test for both groups (respectively: r=0.6 / p<0.001; r=0.6 / p<0.001). In CFG, the level test had a significant association (r=0.4 - p=0.02) with %FEV1. Conclusions: Children with cystic fibrosis presented functional limitation in the Modified Shuttle Test, which was influenced by lung function.

Clinical use of the modified shuttle test in children with cystic fibrosis: Is one test sufficient?

“…The systematic review by Parreira et al 36 indicates that MST is a reliable test for the evaluation of chronic respiratory diseases. It is reproducible in healthy children 37 and in children with CF but not in children with significant pulmonary impairment 7,25,30–38 . The findings of the present study confirm the good reproducibility of the MST in children and adolescents with mild pulmonary impairment.…”

“…It is reproducible in healthy children 37 and in children with CF but not in children with significant pulmonary impairment. 7,25,[30][31][32][33][34][35][36][37][38] The findings of the present study confirm the good reproducibility of the MST in children and adolescents with mild pulmonary impairment.…”

“…Studies have shown that HR behavior is an important indicator of functional performance in the MST 2,21 . Reports have shown that the increase in resting HR is associated with a reduction in the DA in patients with CF 30 . In the present study, when the determinants of the DA over time were evaluated, this association was also observed.…”

“…2,21 Reports have shown that the increase in resting HR is associated with a reduction in the DA in patients with CF. 30 In the present study, when the determinants of the DA over time were evaluated, this association was also observed. The variation in HR assessed by the difference between peak and baseline HR may be considered as an indicator of overload with direct repercussions on the DA in the MST.…”

“…We assessed patients with CF using three distinct evaluations (clinic visits) with a minimum interval of 3 months between them. Although we speculated that the 3‐month interval between tests could be an important factor in reducing reproducibility, which would reinforce the requirement of two tests in each evaluation, 30,31 our results strongly refuted this assumption, as the longitudinal follow‐up of patients with stable CF disease showed that one MST is sufficient to assess the patient's exercise capacity.…”