Sit-to-stand test in children with bronchiectasis: Does it measure functional exercise capacity?

Area of Science:

• Pediatric Pulmonology
• Exercise Physiology
• Respiratory Medicine

Background:

• The six-minute walk test (6MWT) is a standard for functional exercise capacity, but the 30-second sit-to-stand test (30s-STST) offers a simpler alternative.
• Both tests are self-paced and suitable for sub-maximal effort assessments in conditions like bronchiectasis (BE), COPD, and cystic fibrosis.

Purpose of the Study:

• To investigate the association between 30s-STST and 6MWT in children with BE and healthy controls.
• To explore the cardiorespiratory burden and discriminative properties of both tests in this population.

Main Methods:

• Sixty children (6-18 years) with non-cystic fibrosis BE and 20 healthy controls performed 30s-STST and 6MWT.
• Cardiorespiratory responses (heart rate, SpO2, dyspnea) were recorded during both tests.

Main Results:

• 30s-STST explained 52% of 6MWT variance in the BE group (r=0.718, p<0.001) vs. 20% in controls (r=0.453, p=0.045).
• 6MWT showed greater cardiorespiratory demand than 30s-STST.
• Children with BE had significantly lower 30s-STST and 6MWT results compared to healthy controls (p<0.01).
• Both tests demonstrated similar discriminative properties for identifying BE (AUC for 30s-STST=0.765, 6MWT=0.693, p=0.466).

Conclusions:

• The 30s-STST is a valid and reliable alternative for assessing functional exercise capacity in children with bronchiectasis.
• Both 30s-STST and 6MWT have comparable discriminative value for identifying children with BE.