Validity of MemTrax test based on continuous visual recognition tasks online as a screening test for amnestic mild cognitive impairment in Chinese population / 中华神经科杂志

ABSTRACT

Objective:To explore the use of internet-based continuous visual recognition task (MemTrax test, MTX) as a rapid screening tool for amnestic mild cognitive impairment (aMCI).Methods:Sixty-four patients with aMCI and 64 individuals with normal cognition as healthy controls were enrolled respectively from Department of Neurology and Health Examination Center of the First Affiliated Hospital of Kunming Medical University from August 2018 to December 2019. Montreal Cognitive Assessment (MoCA) scale and MTX were adopted to assess the cognitive function of all subjects. The total adjusted MoCA scale score, correct rate of MTX, reaction time of MTX and MTX score were obtained and statistically analyzed.Results:The adjusted MoCA scale scores of aMCI patients and healthy controls were 19 (14, 24) and 26 (24, 27; Z=6.795), the correct rate of MTX of aMCI patients and healthy controls were 74% (60%, 80%) and 88% (84%, 94%; Z=8.359), and the MTX score of aMCI patients and healthy controls were 51.11±14.07 and 70.56±14.91 ( t=7.590), respectively, all with statistically significant difference ( P<0.001). Reaction time of MTX of aMCI patients and healthy controls was 1.401 (1.253, 1.590) s and 1.277 (1.163, 1.410) s, respectively ( Z=3.083, P<0.01). After adjustment for age, physical or mental occupation, exercise, hypertension, hyperlipidemia, stroke, sleep time, as well as smoke, the linear regression showed that the aMCI patients had a significant decrease of adjusted MoCA score, correct rate of MTX and MTX score ( P<0.001), and an extension of reaction time of MTX ( P=0.071), compared with the controls. By MTX and MoCA scale assessment, the best cutoff value was 81% for correct rate of MTX and 23 for adjusted MoCA scale score respectively for the prediction of aMCI (with sensitivity of 79.7%, 93.8% respectively, and specificity of 68.8%, 82.8% respectively). The area under the curve (AUC) of correct rate of MTX was 0.93 (95% CI 0.89-0.97, P<0.001), and the AUC of adjusted MoCA score was 0.85 (95% CI 0.78-0.91, P<0.001). There was a statistically significant difference in paired comparison of the two AUCs (χ2=4.620, P<0.05). Conclusion:MTX acts better for the detection of aMCI than MoCA scale, and correct rate of MTX<81% can be considered as the existence of MCI.