Supplementary Material for: Intradialytic Cognitive and Aerobic Exercise Training to Preserve Cognitive Function: IMPCT, A Multi-Dialysis Center 2x2 Factorial Block-Randomized Controlled Trial

Introduction: Patients with end-stage kidney disease (ESKD) develop cognitive impairment due to comorbidities and dialysis dependence. Among community-dwelling older adults, cognitive (CT) and exercise training (ET) are promising interventions to preserve cognition; these interventions may be tailored for adults undergoing in-center hemodialysis. Methods: Adult (≥18 years) English-speaking patients undergoing hemodialysis (within 3 months to 3 years of initiation) were enrolled in a 2x2 factorial randomized controlled trial: Interventions Made to Preserve Cognitive Function Trial (IMPCT). Participants (n=121) were block-randomized (09/2018-02/2023) into 4 arms: control (SC) (n=26), intradialytic web-based CT (n=31), ET using foot peddler (n=29), and combined CT+ET (n=35). Participants underwent assessments at baseline and 3 months for executive function, global cognitive function, clinical outcomes, and patient-centered outcomes. We estimated 3-month executive function change (primary outcome) and secondary outcomes using linear regression. Results: There were no differences in 3-month executive function change by arm. Participants exhibited improvement in 3-month global cognitive function in CT+ET arm (Montreal Cognitive Assessment score difference=2.1, 95%CI:0.4-3.9), and self-reported 3-month improvement in perceived health change (score difference=0.8, 95%CI:0.2-1.4) in ET arm. Conclusion: Clinicians may encourage CT+ET for hemodialysis patients to improve short-term global cognitive function and perceived health. The long-term benefits of these interventions warrant further study. This trial was registered at clinicaltrials.gov (NCT03616535). URL: https://clinicaltrials.gov/study/NCT03616535.