Subgroups of mild cognitive impairment based on cognitive function among Chinese older adults

Abstract

Due to the heterogeneity of mild cognitive impairment (MCI), the key points for non-pharmaceutical therapies cannot be determined. Examining impairment characteristics among different MCI subgroups would therefore be beneficial to the development of non-pharmaceutical therapies. To characterize the subgroups of older Chinese with MCI, and examine factors associated with the membership of distinct subgroups. This cross-sectional study was conducted between October 2018 and June 2022 in Fujian, East China, with 1017 older adults with MCI deemed eligible. Exclusion criteria included any diagnosis of other neurological or psychiatric conditions that could affect cognition. Participants underwent a neuropsychological test that assessed memory, language, attention, and executive function(s), and completed a questionnaire collecting their socioeconomic and clinical variables. Neuropsychological test scores were transformed to z-scores, which were then examined using latent class analysis. Associations between socioeconomic and clinical variables, and MCI subgroups were assessed using multinomial logistic regression analysis. Three MCI subgroups were identified: G1 “Minimally impairment” (56.64%), G2 “Moderate impairment” (36.28%) and G3 “Worst impairment” (7.08%). Age, place of residence, marriage status, living status, and participation in intellectual activities differed significantly across the three MCI subgroups (P<0.05). Compared with the Minimally impairment group, participants with Worst impairment were less likely to participate in intellectual activity and more likely to live in a nursing home. Cognitive function is a suitable foundation for establishing classifications among individuals with MCI. Non-pharmalogical therapies may target older adults at higher risk of moderate or worst impairment.