Abstract
<jats:title>Abstract</jats:title> <jats:sec> <jats:title>Background</jats:title> <jats:p>Population aging is rapidly increasing the burden of multimorbidity and frailty, yet there is limited evidence on how healthy aging policies are implemented across different demographic and health system contexts.</jats:p> </jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>We conducted a mixed-methods comparative case study in Spain, Italy, Chile, and Colombia, integrating a Targeted review of policy documents and relevant literature, quantitative indicators, and expert interviews.</jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Chile and Colombia showed faster aging dynamics (compound annual growth rates of 4.18% and 4.21%) than Italy (1.96%) and Spain (1.39%), with estimated doubling times of 17 versus 36–50 years. All four countries have established policy frameworks; implementation remains uneven. Key barriers included fragmented services, limited community care, workforce constraints, and misaligned financing.</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>The central challenge lies not in the absence of policy frameworks but in their effective implementation. Strengthening primary care, embedding frailty assessment, and improving health–social care integration are key priorities for systems facing rapid demographic transition.</jats:p> </jats:sec>