BACKGROUND: Dementia is a major global mortality cause and key driver of disability in older adults, imposing multidimensional burdens. As China's population ages, accurate prevalence estimates and care need assessments are essential for equitable policy planning. This study investigates young- and late-onset dementia prevalence while comparing health service utilization and unmet care needs between affected and unaffected populations.

METHODS: Utilizing China Mental Health Survey data (2013-2015) with multistage probability sampling, we identified 12,663 nationally representative adults aged ≥55 years. Of these, 10,839 completed Stage I assessments and 2,261 received Stage II evaluations, supplemented by psychiatric assessments of initial non-participants (n=197). Dementia diagnosis followed DSM-IV criteria via validated cognitive/functional instruments. Health service utilization and multidimensional care needs (ADLs/IADLs/safety) were quantified through participant/informant interviews.

RESULTS: Among 2 458 participants assessed, dementia prevalence was 2.65% (55-64y) and 5.56% (≥65y). Rural residents showed consistently higher rates than urban counterparts across age groups. Significant education gradients emerged, with urban prevalence decreasing with higher education while rural patterns differed. Individual living with dementia required substantially more care for both cohorts (55-64 years: 37.4% vs 11..9%, +81.3 monthly hours; 65+ years: 62.6% vs 13.4%, +88.8 monthly hours) without increased health service utilization.

CONCLUSION: This national study reveals substantial dementia burden in China, exposing systemic healthcare deficiencies through misaligned functional care needs and medical engagement. The neglect of chronic disability management in aging populations necessitates urgent integration of prevention strategies and tailored support frameworks within primary care systems.