Alzheimer's disease burden in China (ABC) study: protocol for a nationwide multicentre cross-sectional and prospective cohort study.

INTRODUCTION: Alzheimer's disease (AD) is imposing an increasing public health and socioeconomic burden. In China, rapid population ageing is sharply increasing disease burden. Previous studies have shown that AD-related costs are mainly driven by long-term informal care. However, evidence in China remains limited by an incomplete cost framework and insufficient consideration of caregivers' burden and indirect costs. Notably, the National Dementia Action Plan (2024-2030), issued by the Chinese government, marks a major shift to early detection and comprehensive care of AD, highlighting the urgent need for nationally representative economic evidence to support policy implementation. This study aims to evaluate the economic burden and quality of life of patients with AD and their caregivers in mainland China, and is the first nationwide study to include individuals with amnestic mild cognitive impairment, providing foundational data for future health technology assessment of early AD interventions. METHODS AND ANALYSIS: Baseline characteristics will be presented and compared using t-tests or χ2 tests. Economic burden will be estimated by calculating the per capita cost and weighted national total based on provincial numbers of patients with AD. Indirect costs will be assessed using locally adapted replacement cost approach and forgone wages approach. The analysis will be stratified by disease severity and age. Future burden will be projected by linking data from China Statistical Yearbook 2025 and the UN World Population Prospects 2024. Unmet care needs, AD-related catastrophic health expenditure and AD dependency ratio (ADDR) will also be assessed. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Ethics Committee of Xuanwu Hospital, Capital Medical University (No. 2023132). The study has been registered at ClinicalTrials.gov (NCT05995418) and the Chinese Clinical Trial Registry (ChiCTR2300074723). The results from this study will be actively disseminated through research articles and conference presentations. TRIAL REGISTRATION NUMBERS: NCT05995418; ChiCTR2300074723.