Progression and Reversion of Mild Cognitive Impairment：a Study Using Data from the Uniform Data Set

Abstract

BackgroundMild cognitive impairment (MCI) has highly variable cognitive trajectories. Approximately 10% to 15% of MCI patients progress to dementia, and nearly 24% revert to normal cognition each year. There are few studies on the progression and reversion of MCI, especially there version of MCI to normal cognition.ObjectiveTo construct a multi-class classification model of MCI outcomes (reversion, stabilization and progression) and to explore the possible associated factors of these outcomes.MethodsData were collected from the National Alzheimer's Disease Coordinating Center Unified Data Set, involving 397 patients who were initially diagnosed with MCI during 2005—2019 with at least two follow-ups and complete clinical and follow-up data. Patients' demographic information, physical examination, disease history, and measurement results by assessment scales in MCI were selected for analysis. Boruta was used for feature selection. Random forest was used for supporting the classification of MCI outcomes. A stepwise multinomial logistic regression was used to explore the associated factors of different MCI outcomes.ResultsOf the 397 cases, 124 (31.23%) reverted to normal cognition, 77 (44.58%) were in stable condition, and 96 (24.18%) progressed to dementia. In the multi-classification task, the accuracy of direct three-class classification was 67.58%. In multiple binary classifications, the accuracies of reversion and stabilization, and reversion and progression were above 90%. Among the hierarchical three-class classification, the accuracy based on stabilization→ reversion → progression was 84.38%. Stepwise multinomial Logistic regression analysis showed that age ≥80 years 〔OR=0.260, 95%CI (0.117, 0.574) 〕, self-reported cognitive impairment 〔OR=0.295, 95%CI (0.139, 0.623) 〕, and decreased Clinical Dementia Rating (CDR) scores〔OR=0.220, 95%CI (0.092, 0.525) 〕 were associated with decreased risk of MCI progressing to dementia, while history of stroke 〔OR=2.896, 95%CI (1.370, 6.122) 〕, fecal incontinence 〔OR=6.556, 95%CI (1.787, 24.047) 〕, and higher Functional Activities Questionnaire score〔OR=1.048, 95%CI (1.003, 1.095) 〕were associated with increased risk of MCI progressing to dementia. Decreased probability of reversion from MCI to normal cognition was related to age ≥80 years 〔OR=0.289, 95%CI (0.091, 0.914) 〕, obesity 〔OR=0.236, 95%CI (0.075, 0.740) 〕, self-reported cognitive impairment 〔OR=0.289, 95%CI (0.111, 0.757) 〕, and higher CDR scores 〔OR=0.015, 95%CI (0.003, 0.089) 〕, while increased probability of reversion from MCI to normal cognition was related to higher MMSE score 〔OR=1.708, 95%CI (1.428, 2.043) 〕 and higher numbers of correct naming of animals 〔OR=1.139, 95%CI (1.046, 1.240) 〕.ConclusionThe outcome of MCI patients is affected by multiple factors. Advanced age, obesity, history of stroke, fecal incontinence, self-reported cognitive impairment and reduced functional activity were important factors influencing MCI progression and reversion.

Keywords

• |cognitive dysfunction|cognition|reversion|alzheimer disease|outcome|muti-classification|root cause analysis