Interim analysis of changes in daily step counts as the primary outcome in a telerehabilitation study for hemodialysis participants

Hemodialysis (HD) participants often exhibit significantly lower physical activity (PA) levels than recommended, primarily due to time-intensive dialysis sessions. Physical inactivity in HD participants correlates with increased cardiovascular morbidity and mortality. As cardiovascular disease is the leading cause of death in CKD participants, improving physical activity levels could play a crucial role in cardiovascular risk reduction. Telerehabilitation (TR), combining wearable activity trackers and structured feedback, offers a promising approach to enhance PA in this population. However, evidence regarding its effectiveness in HD participants remains limited.

This interim analysis evaluates the impact of telerehabilitation on daily step counts in the first 15 participants of an ongoing randomized crossover trial. We hypothesized that TR would significantly increase step counts, contributing to cardiovascular risk reduction, compared to usual care.

This randomized crossover trial included HD participants (n=15) from Jessa Hospital, Hasselt, Belgium. Participants underwent two 3-month interventions: TR combined with usual care and usual care alone, without a wash-out period. During the TR phase, participants used Fitbit® Charge 5 trackers, receiving weekly structured feedback and step goals aiming for a 10% weekly increase.

The presence of a carry-over effect was assessed using an independent t-test comparing cumulative step counts per patient across sequences. No significant carry-over effect was observed (p>0.05). A linear mixed model was fitted with step count as the dependent variable. Fixed effects included sequence, period, and treatment.

The main daily step count was 3480 steps (SD: 1692). Estimated marginal means suggested higher average daily step counts during TR (4708 steps/day; 95% CI: 3379–6036) compared to standard care (3244 steps/day; 95% CI: 1916–4573). The mean difference between treatments was 1464 steps/day (95% CI: -415.4 to 3342.5), reflecting a moderate effect size

(Cohen's d = 0.45). However, the linear mixed model analysis showed that this difference did not reach statistical significance (p=0.12).

The interim analysis suggests that telerehabilitation, facilitated by wearable activity trackers and structured feedback, may enhance physical activity in HD participants. Although the mean difference in daily steps between TR and standard care did not reach statistical significance, the moderate effect size suggests a clinically relevant improvement. This potential clinical relevance highlights the promise of TR as an accessible, scalable intervention to improve cardiovascular outcomes in HD participants.

Average steps per day