Investigation of the risk and preventive factors for progression of mild cognitive impairment to dementia: a 6-year follow-up study

Background: To investigate the cognition change of mild cognitive impairment (MCI) during a 6-year follow-up, and to evaluate the preventive and risk factors for MCI progression to dementia. Methods: : This cross-sectional study was based on the results of the epidemiological survey in 2011 (No. PKJ2010-Y26). A total of 441 MCI individuals, 60 years and above were involved. Cognitive function was measured by the mini-mental status examination (MMSE), clinical dementia rating (CDR), montreal cognitive assessment (MoCA), and daily living scale (ADL). The association between demographic characteristics and MCI outcomes were evaluated using single-and multi-factor ordered logistic regression analysis models. Results: : Exclusion of the relocated community, the final follow-up rate was 43.8%. Individuals who were older, had more children, not in marriage, and with high income were easily lost to follow-up. Of the 441 MCI, 77 progressed to dementia (MCIp, 17.5%, 95% CI: 14.4-21.6%), 356 remained stable (MCIs, 80.7%, 95% CI: 77.0-88.4%), and 8 reverted to normal cognition (MCIr, 1.8%, 95% CI: 0.6-3.0%) at follow-up in 2017. Diabetes ( P =0.047) and past occupations as managers ( P =0.028) increased the risk of MCI progression to dementia. While, high education ( P =0.006) was the protective factor of MCI progression. Conclusions: : High education, nondiabetic, and past occupation as a technical staff might prevent the progression of MCI to dementia. Keywords: Mild cognitive impairment; dementia; ordered logistic regression analysis; education; diabetes; past occupation.