The Hubei Memory and Aging Cohort Study: Study Design, Baseline Characteristics, and Prevalence of Cognitive Impairments

Background: Despite the improved access to health services in China, inadequate diagnosis and management of dementia are common issues, especially in rural regions. Objective: The Hubei Memory & Aging Cohort Study was designed as a prospective study in Central China to determine the prevalence, incidence, and risk factors for dementia and mild cognitive impairment (MCI) among urban and rural older adults. Methods: From 2018-2020, participants aged >= 65 years were screened, and data regarding their life behaviors, families, socio-economic status, physical and mental health, social and psychological factors, and cognition were collected. Diagnoses of MCI and dementia were made via consensus diagnosis using the Diagnostic and Statistical Manual of Mental Disorders fourth edition criteria. Results: Of 8,221 individuals who completed their baseline clinical evaluation, 4,449 (54.1%) were women and 3,164 (38.4%) were from remote rural areas (average age: 71.96 years; mean education period: 7.58 years). At baseline, 25.98% (95% confidence interval [CI]: 24.99-26.96) and 7.24% (95% CI: 6.68-7.80) of the participants were diagnosed with MCI and dementia, respectively. Prevalence showed a strong relationship with age. The substantial disparities between rural and urban regions in MCI and dementia prevalence and multiple dementia-related risk factors were revealed. Especially for dementia, the prevalence rate in rural areas was 2.65 times higher than that in urban regions. Conclusion: Our results suggested that public health interventions are urgently needed to achieve equitable diagnosis and management for people living with dementia in the communities across urban and rural areas.