Relationship between peripheral muscle strength, exercise capacity and body composition in children and adolescents with cystic fibrosis

ABSTRACT

Study Design

This was a transversal analytical study.

Background

Exercise capacity is usually decreased in cystic fibrosis, impacting the disease prognosis. As well, peripheral muscle strength and nutritional status seem to be related to exercise capacity (EC).

Objective

To verify the relationship between peripheral muscle strength, pulmonary function and body composition with EC in children and adolescents with CF.

Methods

The study included CF children/adolescents that were clinically stable. The disease’s severity was classified according to the Schwachman-Doerschuk score. Initially the subjects underwent bioimpedance and spirometry tests. Quadriceps muscle strength (QMS) and handgrip strength (HG) were evaluated by dynamometry. The Modified Shuttle Walk Test (MSWT) was conducted along with gas analysis in order to measure EC.

Results

Twenty-five children/adolescents (10.30 ± 2.33 years old) participated in the survey. 72% were eutrophic, with a mean FEV1 of 68.55%, predicted percentage of the MSWT walked distance (%WD) was 70.91%, and QMS 65.80%. QMS presented significant correlations with absolute WD (r = 0.54), oxygen peak consumption (r = 0.72), lean body mass (LM) (r = 0.83), and body mass index (BMI) (r = 0.69). HG was related with BMI (r = 0.45) and LM (r = 0.65). There was a difference in the %WD between the groups with higher/lower strength (p = .02).

Conclusion

There was no correlation between HG and EC in this studied sample. Early involvement of QMS was observed even in individuals with low disease severity. This finding reinforces the importance of including this QMS assessment in CF reference centers to monitor, prevent and prescribe adequate exercise training for these individuals.

KEYWORDS:

• Cystic fibrosis
• child
• muscle strength
• nutritional status
• exercise capacity

Acknowledgments

This study was supported by the Research and Innovation Support Foundation of Santa Catarina State, FAPESC/Brazil the under Grant (2017TR645).

Disclosure statement

The authors declare no conflict of interest.

Additional information

Funding

This study was supported by the Research and Innovation Support Foundation of Santa Catarina State, FAPESC/Brazil the under Grant (2017TR645).