Neuropsychiatric Symptoms and Increased Risks of Progression from Amnestic Mild Cognitive Impairment to Alzheimer's Dementia

ABSTRACT

OBJECTIVES: Neuropsychiatric symptoms (NPS) are common in dementia and in mild cognitive impairment (MCI). They might be a predictor of progression to dementia. This study aimed to investigate the effects of NPS on the natural course in MCI. METHODS: 306 community-dwelling Korean elderly with MCI from local dementia center were assessed for NPS using Neuropsychiatric Inventory (NPI). Subjects were assessed again after more than a year from baseline. 52 subjects (17.0%) were progressed to dementia. We compared baseline NPI scores between stable and deteriorated groups. RESULTS: Subjects progressing to dementia had a significantly higher prevalence of NPS (45.3% vs. 65.4%) than subjects who remained stable. Delusion (2.8% vs. 9.6%), agitation/aggression (14.6% vs. 26.9%), depression (21.7% vs. 40.4%) and disinhibition (4.3% vs. 19.2%) were more common in deteriorated group. After adjustment for other variables, on logistic regression analysis, only disinhibition at baseline was shown to be a risk factor for progression to dementia (OR=4.88, 95% CI=1.37-17.36, p=0.01, R²=302). CONCLUSION: These findings suggest that NPS in MCI may be a predictor of progression to dementia. NPS may be a useful item including delusion, agitation/aggression, depression, and disinhibition. To study course and nature of NPS may lead to better understanding of Alzheimer's disease.