The six-minute walk test predicts cardiorespiratory fitness in individuals with aneurysmal subarachnoid hemorrhage.
BACKGROUND
Peak oxygen uptake (VO2peak) established during progressive cardiopulmonary exercise testing (CPET) is the "gold-standard" for cardiorespiratory fitness. However, CPET measurements may be limited in patients with aneurysmal subarachnoid hemorrhage (a-SAH) by disease-related complaints, such as cardiovascular health-risks or anxiety. Furthermore, CPET with gas-exchange analyses require specialized knowledge and infrastructure with limited availability in most rehabilitation facilities.


OBJECTIVES
To determine whether an easy-to-administer six-minute walk test (6MWT) is a valid clinical alternative to progressive CPET in order to predict VO2peak in individuals with a-SAH.


METHODS
Twenty-seven patients performed the 6MWT and CPET with gas-exchange analyses on a cycle ergometer. Univariate and multivariate regression models were made to investigate the predictability of VO2peak from the six-minute walk distance (6MWD).


RESULTS
Univariate regression showed that the 6MWD was strongly related to VO2peak (r = 0.75, p < 0.001), with an explained variance of 56% and a prediction error of 4.12 ml/kg/min, representing 18% of mean VO2peak. Adding age and sex to an extended multivariate regression model improved this relationship (r = 0.82, p < 0.001), with an explained variance of 67% and a prediction error of 3.67 ml/kg/min corresponding to 16% of mean VO2peak.


CONCLUSIONS
The 6MWT is an easy-to-administer submaximal exercise test that can be selected to estimate cardiorespiratory fitness at an aggregated level, in groups of patients with a-SAH, which may help to evaluate interventions in a clinical or research setting. However, the relatively large prediction error does not allow for an accurate prediction in individual patients.
['Harmsen|Wouter J|WJ|', 'Ribbers|Gerard M|GM|', 'Slaman|Jorrit|J|', 'Heijenbrok-Kal|Majanka H|MH|', 'Khajeh|Ladbon|L|', 'van Kooten|Fop|F|', 'Neggers|Sebastiaan J C M M|SJ|', 'van den Berg-Emons|Rita J|RJ|']
D000328:Adult D000368:Aged D000072599:Cardiorespiratory Fitness D003430:Cross-Sectional Studies D005080:Exercise Test D005260:Female D006801:Humans D002532:Intracranial Aneurysm D008297:Male D008875:Middle Aged D015203:Reproducibility of Results D013345:Subarachnoid Hemorrhage D000070857:Walk Test
cardiorespiratory fitness subarachnoid hemorrhage VO2peak cardiopulmonary exercise test CPET rehabilitation 6MWT Six-min walk test peak oxygen consumption standard error of the estimate