Evaluation value of the Cog-12 scale combined with apolipoprotein E genotyping in elderly population with mild cognitive impairment

Objective To evaluate the capacity of the cognitive-12 scale (Cog-12 scale) combined with apolipoprotein E genotyping in screening mild cognitive impairment (MCI) in elderly people over 65 years old. Methods Elderly patients aged over 65 years old were selected. According to cognitive levels, they were divided into three groups: a control group (n=31), an MCI group (n=29) and an Alzheimer’s disease (AD) group (n=27). Each group completed the evaluation of Cog-12 scale and the Relevant Outcome Scale for Alzheimer’s Disease (ROSA), Montreal Cognitive Assessment (MoCA), the Mini Mental State Examination (MMSE) and apolipoprotein E genotyping. Results Compared with the control group (2.6±1.4), the Cog-12 score was (9.1±4.2) for the MCI group and (22.5±7.2) for the AD group, both of which significantly increased (P<0.05). The concurrent validity of ROSA, MoCA and MMSE was -0.844, -0.897 and -0.881, respectively. For MCI, its diagnostic sensitivity was 76.5%, with a specificity of 90.2%, and the AUC value of 0.875 respectively. The most common genotypes of ApoE was ε³ε³ in the control group, the MCI group and the AD group, where genotypes the percentages of ε³ε³ and ε⁴ε⁴ were higher in the AD and MCI groups than that in the control group(P<0.05). Conclusions Cog-12 is a simple and effective tool for screening cognitive function, and genotypes ε³ε³ and ε⁴ε⁴ are more commonly seen in MCI and AD patients. This combined detection can effectively detect MCI in elderly population, so as to better evaluate the risk factors of dementia and disease progression.