Th. Mercer et al., DEVELOPMENT OF A WALKING TEST FOR THE ASSESSMENT OF FUNCTIONAL-CAPACITY IN NONANEMIC MAINTENANCE DIALYSIS PATIENTS, Nephrology, dialysis, transplantation, 13(8), 1998, pp. 2023-2026
Background. Walk tests may be useful adjuncts or even alternatives to
the assessment of peak oxygen uptake (VO2 (peak)) in patients with low
functional capacity. Walk tests are easy to administer, appear to be
well tolerated by patients and may represent a more meaningful measure
for a patient group as they assess capability as well as fitness. How
ever, the use of walk tests for the assessment of functional capacity
in maintenance dialysis patients has received scant attention. The aim
of this study was to assess the validity of a walking-stair-climbing
test to predict VO2 (peak) in non-anaemic maintenance dialysis patient
s. Methods. In the validation phase of the study, 14 subjects complete
d a cycle ergometer-graded exercise test (GXT) for the determination o
f VO2 (peak) and a walking-stair-climbing task (WALK), each separated
by a period of 7 days. Three weeks later, 18 subjects completed two WA
LK tests, each separated by a period of at least 48 h, to facilitate r
eliability estimation. Estimates of differentiated and undifferentiate
d ratings of perceived exertion (RPE) were obtained during and immedia
tely consequent to all exercise tests. Results. VO2 (peak) (ml kg min)
was significantly correlated with total WALK time (s) (r = -0.83; P<0
.001). VO2 peak (ml/kg/min) could be predicted from total WALK time wi
th a standard error of prediction of 11%. Reliability assessment revea
led no significant differences for any aspect of the WALK test perform
ance, with intraclass correlation coefficients ranging from r=0.71 (RP
Elegs) to 0.96 (total WALK time). Conclusion. These results indicate t
hat the WALK test is a valid, reliable and potentially useful method b
y which to assess the functional capacity of non-anaemic maintenance d
ialysis patients.