Group-Based Exercise in CKD Stage 3b to 4: A Randomized Clinical Trial

RATIONALE & OBJECTIVE: We aimed to test interventions to improve physical activity in persons with advanced chronic kidney disease not yet receiving dialysis. STUDY DESIGN: Randomized controlled trial with parallel-group design. SETTING & PARTICIPANTS: We embedded a pragmatic referral to exercise programming in high-volume kidney clinics servicing diverse populations in San Jose, CA, and Atlanta, GA. We recruited 56 participants with estimated glomerular filtration rates < 45 mL/min/1.73 m(2). INTERVENTIONS: We randomly assigned participants to a mobile health (mHealth) group—wearable activity trackers and fitness professional counseling, or an Exercise is Medicine intervention framework (EIM) group—mHealth components plus twice-weekly small-group directed exercise sessions customized to persons with kidney disease. We performed assessments at baseline, 8 weeks at the end of active intervention, and 16 weeks after passive follow-up and used multilevel mixed models to assess between-group differences. OUTCOMES: Activity tracker total daily step count. RESULTS: Of 56 participants, 86% belonged to a racial/ethnic minority group; randomly assigned groups were well balanced on baseline step count. In intention-to-treat analyses, the EIM and mHealth groups both experienced declines in daily step counts, but there was an attenuated reduction in light intensity physical activity (standard error 0.2 [5.8] vs −8.5 [5.4] min/d; P = 0.08) in the EIM compared with the mHealth group at 8 weeks. In as-treated analyses, total daily step count, distance covered, and light and moderate-vigorous activity minutes per day improved in the EIM group and declined in the mHealth group at 8 weeks (standard error +335 [506] vs −884 [340] steps per day; P = 0.05; P < 0.05 for secondary measures), but group differences faded at 16 weeks. There were no differences in quality-of-life and mental health measures during the study. LIMITATIONS: Small sample size, limited duration of study, assessment of intermediate outcomes (steps per day). CONCLUSIONS: A clinic-integrated referral to small-group exercise sessions is feasible, safe, and moderately effective in improving physical activity in an underserved population with high comorbid conditions. FUNDING: Normon S Coplon Applied Pragmatic Clinical Research program. TRIAL REGISTRATION: NCT03311763