CEEEC-II: A 12-Week Physical and Cognitive Enrichment Extension Study in Older Stroke Survivors With Multimorbidity

CEEEC-II is the prospective, open-label extension of the CEEEC Phase I 2×2 factorial cluster-randomized trial (NCT06975501). The extension is conducted in 32 community health service stations in Kunshan, Jiangsu Province, China. Up to 420 participants who completed the Phase I endpoint assessment will be approached consecutively. The estimated Phase II enrollment is 356 participants, with a target of at least 320 participants completing the primary endpoint assessment. All participants will undergo a new eligibility review and provide written informed consent specifically for CEEEC-II. No new randomization will occur. Each participating community health service station will retain its Phase I cluster assignment: physical and nutrition enrichment only, AI-enabled cognitive enrichment only, combined physical, nutrition, and cognitive enrichment, or usual community-based care. This preserves the original 2×2 factorial structure while recognizing that the Phase II cohort is a selectively re-consented extension cohort rather than a newly randomized sample. Each participant will receive 12 weeks of the intervention assigned to the community cluster. The active program comprises eight physician-led Vitality Camp sessions and four volunteer-led reinforcement activities. The upgraded physical and nutrition component integrates age-appropriate aerobic, resistance, balance, and flexibility exercises, incorporates Baduanjin-based movements, and provides practical nutrition education. The upgraded cognitive component combines health education with age-adapted, AI-enabled large-screen interactive games designed to engage memory, attention, processing speed, visuospatial ability, and executive function. Reinforcement activities and take-home materials support continued participation and practice between group sessions. Participants in the usual-care arm continue routine community-based stroke and chronic disease management without the structured Phase II physical or cognitive enrichment program. Assessments will be conducted at baseline and approximately 12 weeks after intervention initiation. The primary outcome is an intrinsic capacity composite score derived from cognition, locomotion, vitality, and psychological capacity domains. The primary estimand is the marginal effect of the cognitive enrichment factor. The physical enrichment factor effect is a key secondary estimand. Cognitive function measured with the Montreal Cognitive Assessment is retained as a secondary outcome in continuity with Phase I. Other prespecified outcomes include MemTrax performance, physical function, nutritional status, depressive symptoms, blood pressure, health-related quality of life, medication adherence, physical activity, activities of daily living, falls, hospitalization, and recurrent stroke. Analyses will account for community-level clustering and the original factorial assignment.