Gfaa 012
Gfaa 012
Gfaa 012
doi: 10.1093/ndt/gfaa012
Cumulative risk of
hospitalization
simple, personalized, home-based training period in dialysis 0.2
(HD and PD patients). Exclusion criteria were very severe phys-
ical limitation (e.g. amputation and/or any other limitation to
ambulation), clinical limitation, severe effort angina, Stage IV 0.1
New York Heart Association (NYHA) heart failure, any inter-
current illness requiring hospitalization and a high degree of fit- P=0.04
ness (ability to walk a distance of >550 m in 6 min). Dialysis 0
patients were randomly assigned to the active arm (exercise) 0 50 100 150 200
and the control arm and all patients were stratified according to Time (days)
the NYHA classification. The performance tests in this trial
FIGURE 2: Reverse Kaplan–Meier survival curves for hospitalization
were two very well-validated tests such as the 6-min walking in patients in the active group and those in the control group of the
test and the sit-to-stand (STS) test. The primary analysis, i.e. the EXCITE trial (redrawn from ref. [12]).
major clinical endpoints, was the assessment of whether a 6-
month home-based training intervention improves physical complications during exercise were reported in the active arm
performance as measured by the 6-min walking test and the of the trial. Of note, in an analysis restricted to patients who
STS and quality of life [Kidney Disease Quality of Life completed the trial (i.e. in a ‘per protocol’ analysis), the cumula-
(KDQOL), Rand Corporation, validated in Italian CKD tive risk of hospitalization was lower [hazard ratio 0.46 (95% CI
patients]. The secondary outcomes included all-cause mortality. 0.22–0.97); P ¼ 0.04] in patients in the active group than those
In addition to these outcomes, the safety of the exercise pro- in the control group (Figure 2). This finding was germane to an-
gramme was assessed. The whole dialysis population cohort other analysis of the EXCITE trial [18] testing the predictive
(the source population) consisted of 714 individuals. The num- value of the 6-min walking test per se (i.e. independently of the
ber of eligible patients was 473, and among those, roughly 300 allocation arm) for death, cardiovascular events and hospitali-
agreed to participate in the study and were randomized. zation in the intention-to-treat population (n ¼ 296 dialysis) of
Randomization was effective and at baseline the two groups (ac- the trial. In multiple Cox models—adjusting for the allocation
tive arm and control arm) were highly comparable. arms as well as for traditional and non-traditional risk factors—
The distance covered during the 6-min walking test im- a 20-m increase in the 6-min walking test entailed a 6% reduc-
proved in the exercise group (mean distance 6 SD: baseline, tion (P ¼ 0.001) of the risk of the composite endpoint (i.e. mor-
328 6 96 m; 6 months, 367 6 113 m) but not in the control tality, fatal and non-fatal cardiovascular events and
group (baseline, 321 6 107 m; 6 months, 324 6 116 m; hospitalizations) and similar relationships existed between the
P < 0.001 between groups). Similarly, the five times STST time same test with mortality (P < 0.001) and hospitalizations
improved in the exercise group (mean time 6 SD: baseline, (P ¼ 0.03) considered as single outcomes [18].
20.5 6 6.0 s; 6 months, 18.2 6 5.7 s) but not in the control group Moreover, a secondary analysis of the EXCITE trial con-
(baseline, 20.9 6 5.8 s; 6 months, 20.2 6 6.4 s; P ¼ 0.001 be- firmed the beneficial effect of exercise on physical performance
tween groups). These results in a relatively large cohort of dialy- and cognitive function in dialysis patients >65 years of age [19].
sis patients, the largest so far, indicate that some type of Interestingly, an analysis of the EXCITE trial limited to PD
physical activity is beneficial in this high-risk population. patients (Mallamaci F. et al., unpublished data) showed that the
Another important endpoint in the EXCITE trial was quality effect of physical exercise on the 6-min walk test in PD patients
of life, which was measured by the KDQOL Short Form was identical to that observed in the whole study population. In
(KDQOL-SF) and was performed using the version translated contrast, the results for the STS test in PD patients were not dif-
into Italian and specifically validated in a sample of the Italian ferent in the exercise group compared with the control group,
population. It is well known that an important aspect in clinical but this could be due to the relatively small number of PD
research is the assessment of cognitive function, which is a patients in the study.
broad term defined as ‘an intellectual process by which one In conclusion, so far the scientific community has dedicated
becomes aware of, perceives, or comprehends ideas. It involves a huge amount of effort to studying the burden of physical inac-
all aspects of perception, thinking, reasoning, and remember- tivity in dialysis patients [1], as well as the impact of physical ex-
ing’. Dialysis patients in the active arm of this trial showed a sig- ercise in the same patient population, but these programmes
nificant improvement in cognitive function, which is in part represent important barriers for their diffusion as routine treat-
connected to social relationships. The cognitive function score ment for the following reasons: (i) these programmes are con-
in the kidney disease component of the KDQOL-SF improved ceived to be performed during dialysis sessions [20] and thus
significantly in patients in the exercise arm compared with cannot be extended to the PD population, (ii) they are costly
those in the control arm (P ¼ 0.04). Overall, the training pro- and (iii) they are not standardized and include too many types
gramme was well tolerated and no major symptoms/ of exercise. The first trial that attempted to generalize (i.e. not