Home‐Based Combined Activity and Cognitive Intervention for Post‐Intensive Care Syndrome: A Pilot Randomised Controlled Trial

BACKGROUND: ICU survivors frequently develop post-intensive care syndrome (PICS), a cluster of persistent physical, cognitive and psychological impairments that substantially impair recovery and quality of life. Existing rehabilitation approaches are predominantly monomodal and exercise-focused, yielding inconsistent outcomes and failing to address the multidimensional burden of PICS adequately. AIM: To evaluate the feasibility and preliminary efficacy of COMBAT-ICU, a home-based Combined Activity and Cognitive Intervention for ICU survivors at risk of PICS. STUDY DESIGN: A parallel, three-arm, assessor-blinded pilot randomised controlled trial randomised 36 ICU survivors (1:1:1) to COMBAT-ICU-an 8-week blended program of progressive physical exercise and computerised cognitive training delivered via supervised home visits and online sessions-an exercise-only group or an attention control group. The primary outcomes were feasibility (recruitment, retention and intervention adherence) and safety; secondary exploratory outcomes encompassed PICS severity, physical capacity, cognition, mental health and health-related quality of life (HRQoL). RESULTS: COMBAT-ICU was feasible and safe (36 ICU survivors randomised), with no serious adverse events recorded, retention exceeding 82% at follow-up and session adherence exceeding 90%. COMBAT-ICU produced significantly greater reductions in PICS severity versus attention control at post-intervention (p = 0.014, d = -0.50) and follow-up (p = 0.043, d = -0.45). It also yielded clinically meaningful moderate-to-large effect sizes for walking endurance, global cognition, short-term memory and HRQoL index scores compared with attention control and consistently outperformed exercise-only across cognitive and HRQoL domains. Between-group differences in anxiety and depressive symptoms were small across all active groups. CONCLUSIONS: COMBAT-ICU is feasible and shows promising preliminary efficacy in mitigating PICS. Integrating cognitive and physical training within a home-based blended delivery model may confer synergistic benefits beyond exercise alone, providing domain-specific effect size estimates and a compelling rationale for definitive multicentre trials. RELEVANCE TO CLINICAL PRACTICE: Multidomain home-based rehabilitation is a viable post-discharge strategy for ICU survivors. COMBAT-ICU offers an evidence-informed, scalable framework to enhance survivorship care, pending confirmation in larger, fully powered trials. TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov (NCT06117761).