While regular physical-activity (PA) is beneficial, multimorbid individuals at increased dementia risk may exhibit reduced PA levels. Thus, a more comprehensive understanding of mediating factors responsible for inactivity in this population is needed. This study investigated the impact of a multimodal intervention on PA changes at 24-month follow-up and associated mediating factors among community-dwelling patients aged 60-77, with increased dementia risk determined by the CAIDE Dementia Risk Score. Of 1030 participants recruited, 819 completed the assessment. Thus, a generalized estimating equations model initially assessed differences in PA over 24 months, followed by a tree analysis identifying mediating factors influencing PA changes post-intervention. While no significant effect on regular PA was found during the follow-up (P = .674), subgroup analysis revealed improved self-efficacy (P = .000) associated with increased engagement in PA. Incorporating self-efficacy elements into future strategies is crucial for promoting PA among individuals with multimorbidity and at increased dementia risk.
