Predicting the Conversion From Mild Cognitive Impairment to Dementia

Study on Risk Factors for Prediction of Conversion to Dementia in Patients With Mild Cognitive Impairment

Mild cognitive impairment (MCI) is believed to be the early stage of dementia. The investigators assume that some psychological and imaging risks may predict the conversion. In the current longitudinal study, psychological and imaging data of people with MCI will be obtained at baseline, and will be followed at 26 weeks and 52 weeks. The predictors will be found in comparison with controls.

MCI increases the risk of later developing dementia. About 10-15% of the amnestic form of mild cognitive impairment will progress to Alzheimer's disease in one year. But some people with MCI never get worse. Others with MCI later have test results that return to normal for their age and education.

To develop a new drug for the prevention of dementia(dementia due to Alzheimer's disease or vascular dementia), investigators need a sensitive and specific tool for recognizing patients who will converse to dementia. The investigators want to establish an operational diagnostic criteria instead of a descriptive criteria for mild cognitive impairment.

Inclusion Criteria:

• complaint about cognitive decline compared to previous performance
• objective cognitive impairment in one or more cognitive domains for age
• preservation of independence in functional abilities
• Mini-Mental State Examination(MMSE) scores between 24 and 30
• a Clinical Dementia Rating(CDR) score of 0.5

Exclusion Criteria:

• dementia
• patient with any following disease: Parkinson's disease, multiple system atrophy, normal pressure hydrocephalus, progressive supranuclear palsy, subarachnoid hemorrhage, brain neoplasms, Huntington disease, epilepsy
• depression(HAMD >7) or psychosis
• uncontrolled severe medical conditions(i.e., acute heart failure, renal insufficiency)
• current treatment with benzodiazepines, antidepressants, antipsychotics, or other medications with significant psychotropic or central cholinergic effects
• abnormal thyroid, low vitamin B12 level or low folic acid level
• patient with visual and auditory disorders can't cooperate with neuropsychological assessment
• patient can't cooperate with following up
• informed consent is not obtained