The 30-second chair stand test (CS30) as a predictor of exercise tolerance in elderly individuals (>=75 years) with stage A/B heart failure

Key points

1. 01CS30 was independently associated with peak VO2 in both men and women after adjusting for age, physical function, and frailty measures
2. 02ROC analysis showed moderate accuracy for detecting low exercise tolerance: AUC 0.740 in males and 0.725 in females
3. 03Cut-off values were 18 repetitions for males and 16 repetitions for females to flag low exercise tolerance
4. 04Low exercise tolerance was present in 9.0% of male and 24.0% of female participants
5. 05The test requires no equipment and takes only 30 seconds, making it feasible for outpatient use

How it was conducted

Design

Single-center, cross-sectional, observational study

Participants

493 outpatients aged 75 years and over (296 males, 197 females) with stage A or B heart failure

Setting

Minamino Cardiovascular Hospital outpatient clinic, Japan; March 2021 to December 2022

CS30 procedure

Seated on a 40 cm chair, arms crossed, stand and sit repeatedly for 30 seconds; repetitions counted

Reference standard

Peak VO2 via cardiopulmonary exercise testing (CPX) on bicycle ergometer with gas exchange analysis

Primary analysis

Multivariable linear regression of CS30 on peak VO2 adjusted for confounders; ROC analysis for low exercise tolerance cut-off (peak VO2 below 80% of reference value)

What they found

• Univariable regression: each 1 mL/min/kg increase in peak VO2 associated with 0.532 more CS30 repetitions in males (95% CI 0.394-0.669) and 0.551 in females (95% CI 0.375-0.726)
• Multivariable regression: each 1 mL/min/kg increase in peak VO2 associated with 0.255 more CS30 repetitions in males (95% CI 0.102-0.407, p = 0.001) and 0.282 in females (95% CI 0.043-0.521, p = 0.021)
• Mean CS30 in males: 16.5 repetitions in low exercise tolerance group vs. 20.7 in normal group (p < 0.001)
• Mean CS30 in females: 16.2 repetitions in low exercise tolerance group vs. 20.1 in normal group (p < 0.001)
• AUC for detecting low exercise tolerance: 0.740 (95% CI 0.640-0.841, p < 0.001) in males; 0.725 (95% CI 0.644-0.807, p < 0.001) in females
• CS30 cut-off values: 18 repetitions for males and 16 repetitions for females
• Pearson correlation between CS30 and peak VO2: r = 0.408 (males, p < 0.001); r = 0.406 (females, p < 0.001)

Limitations

• Single-center study with a limited sample size that may not reflect the broader population
• Participants were selected from those able to complete both CS30 and CPX, introducing selection bias and likely overestimating the association
• Pre-existing respiratory diseases and oral medications were not fully accounted for, potentially introducing positive confounding
• Cross-sectional design precludes causal inference and cannot show how CS30 changes as heart failure progresses beyond stages A/B

Why it matters

For patients

Older adults with early heart failure may be able to use this simple chair-stand test as a rough gauge of their fitness level without needing expensive lab equipment.

For clinicians

A CS30 score below 18 in male or below 16 in female patients aged 75 and over may warrant closer evaluation of exercise capacity, particularly where cardiopulmonary exercise testing is unavailable or impractical.

For readers

This study adds early evidence that a 30-second chair stand test can screen for low exercise tolerance in very elderly heart failure patients, though the moderate accuracy and cross-sectional design mean it should complement, not replace, formal assessment.