Comparison of the Sit-to-Stand Test with 6 min walk test in patients with chronic obstructive pulmonary disease

To discuss the utility of Sit-to-Stand Test (STST) compared to the 6min walking test (6MWT) for the evaluation of functional status in patients with chronic obstructive pulmonary disease (COPD).

Fifty-three patients with stable COPD (mean forced expiratory volume in 1s (FEV(1)) 46+/-9% predicted, mean age 71+/-12 year) and 15 healthy individuals (mean FEV(1) 101+/-13% predicted and mean age 63+/-8) were included.

Functional performance was evaluated by STST and 6MWT. During the tests, severity of dyspnea (by Modified Borg Scale), heart rate, pulsed oxygen saturation (SpO(2), by Modified Borg Scale) (by pulse oxymeter), blood pressure were measured. The pulmonary function (by spirometry), quadriceps femoris muscle strength (by manual muscle test) and quality of life (by Nottingham Health Profile Survey) were evaluated.

The STST and 6MWT results were lower in COPD group than the healthy group (P<0.05). During the 6MWT the rise in the heart rate, systolic blood pressure and the decrease in SpO(2) were statistically significant according to STST in COPD groups (P<0.05). The STST and 6MWT were strongly correlated with each other in both groups (P<0.05). Similarly, they were correlated with age, quality of life, peripheral muscle strength and dyspnea severity in COPD groups (P<0.05).

Similar to 6MWT, STST is also able to determine the functional state correctly. Additionally, it produces less hemodynamical stress compared to the 6MWT. In conclusion, STST can be used as an alternative of the 6MWT in patients with COPD.