Mild Cognitive Impairment Reversion and Progression: Rates and Predictors in Community-Living Older Persons in the Singapore Longitudinal Ageing Studies Cohort

Background: Studies report varying rates and predictors of mild cognitive impairment (MCI) progression and reversion.

Methods: We determined MCI reversion and progression among 473 community-living adults aged ≥55 years in the Singapore Longitudinal Ageing Study with an average of 6 years of follow-up and estimated association with baseline variables.

Results: A total of 208 MCI participants reverted to normal cognition (44.0%) and 19 progressed to dementia (4.0%). In a model adjusted for age, gender, education, ethnicity, cardiovascular risk factors/diseases, APOE ε4 status, depressive symptoms, leisure-time activities (LTA), and baseline Mini-Mental State Examination (MMSE), we found that LTA score (OR = 1.07, 95% CI 1.02-1.13), MMSE score (OR = 1.21, 95% CI 1.11-1.31), and subjective memory complaint (OR = 1.83, 95% CI 1.16-2.90) significantly predicted MCI reversion. Controlling for all variables, age (OR = 1.09, 95% CI 1.02-1.17), lower education (OR = 3.26, 95% CI 1.01-10.49), and the metabolic syndrome (OR = 3.13, 95% CI 1.12-8.77) significantly predicted MCI progression. Controlling for age, sex, ethnicity, and education, diabetes significantly predicted MCI progression (OR = 3.19, 95% CI 1.23-8.26), but the presence of other cardiometabolic factors reduced this association to an OR of 2.18 (95% CI 0.72-6.60).

Conclusion: In this relatively younger population, there were higher rates of MCI reversion and lower rates of MCI progression which were predicted by the positive effects of LTA and a higher MMSE score as well as by the deleterious effect of the metabolic syndrome and diabetes.