Cognitive Impairment, P300, and Transforming Growth Factor β1 in Different Forms of Dementia

Abstract

Background: There are currently few biomarkers to assist in early diagnosis of dementias. Objective: To distinguish between different dementias: Alzheimer’s disease (AD), vascular dementia (VaD), and Parkinson’s disease dementia (PDD) using simple neurophysiologic (P300) and laboratory markers (transforming growth factor β1 “TGF-β1”). Methods: The study included 15 patients for each type of dementia and 25 age- and sex-matched control subjects. Dementia patients were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders 4th edition-revised (DSM-IV-R). Modified Mini-Mental State Examination (3MS), Memory Assessment Scale (MAS), P300, and TGF-β1 were examined for each participant. Results: There were no significant differences between groups as regard to age, sex, and education, social, and economic levels. Significant differences between groups were observed in registration and naming variables of the 3MS. Compared with the control group, P300 latency was prolonged in all groups, although to a greater extent in AD and PDD than in VaD. A serum level of TGF-β1 was significantly elevated in all groups but was significantly higher in AD and VaD than in PDD. 3MS tended to correlate with P300 more than TGF-β1, and to be stronger in AD than the other groups. Conclusion: Measurements of P300 latency and serum levels of TGF-β1 can help distinguish AD, PDD, and VaD. P300 was more prolonged in AD and PDD than VaD whereas TGF-β1 was significantly higher in AD and VaD than PDD. Thus P300 and TGF-β1 may be useful biomarkers for detection and evaluation of the extent of cognitive dysfunction.