RT Journal Article
SR Electronic
T1 Determinants of Exercise Capacity Assessed With the Modified Shuttle Test in Individuals With Cystic Fibrosis
JF Respiratory Care
FD American Association for Respiratory Care
SP 643
OP 649
DO 10.4187/respcare.07326
VO 65
IS 5
A1 Fernanda Maria Vendrusculo
A1 Evanirso Silva Aquino
A1 Natália Evangelista Campos
A1 Ingrid Silveira de Almeida
A1 João Paulo Heinzmann-Filho
A1 Karen Caroline Vasconcelos Queiroz
A1 Luanna Rodrigues Leite
A1 Márcio Vinícius Fagundes Donadio
YR 2020
UL http://rc.rcjournal.com/content/65/5/643.abstract
AB BACKGROUND: Patients with cystic fibrosis develop decreased exercise capacity. However, the main factors responsible for this decline are still unclear. Thus, the objective of this study was to evaluate the factors influencing exercise capacity assessed with the modified shuttle test (MST) in individuals with cystic fibrosis.METHODS: A cross-sectional study was carried out in subjects with a diagnosis of cystic fibrosis who were 6–26 y old and were regularly monitored at 2 cystic fibrosis reference centers in Brazil. Individuals who were unable to perform the tests or who exhibited hemodynamic instability and exacerbation of respiratory symptoms were excluded. Anthropometric, clinical, and genotype data were collected. In addition, lung function and exercise capacity were evaluated with the MST.RESULTS: 73 subjects (mean age 12.2 ± 4.9 y and FEV1 76.8 ± 23.3%) were included. The mean distance achieved in the MST was 765 ± 258 m (71.6% of predicted). The distance achieved on the MST correlated significantly with age (r = 0.49, P < .001), body mass index (r = 0.41, P < .001), resting heart rate (r = −0.51, P < .001), and FEV1 (r = 0.24, P = .042). Subjects with FEV1 > 67% of predicted (P = .02) and those with resting heart rate < 100 beats/min (P = .01) had a greater exercise capacity. Resting heart rate, age, and FEV1 (%) were found as significant variables to explain the distance achieved on the MST (R2 = 0.48, standard error = 191.0 m).CONCLUSIONS: The main determinants of exercise capacity assessed with the MST in individuals with cystic fibrosis were resting heart rate, age, and lung function.