Relationship between fibrinogen level and its regulatory gene with Alzheimer's disease and vascular dementia.

OBJECTIVE: Several investigations have shown that the level of fibrinogen (Fg) is associated with the susceptibility to dementia and is usually affected by polymorphisms in its gene. Our study aimed to investigate the relationship between Fg level and the fibrinogen β (FGB) −148C/T gene polymorphism in patients with Alzheimer’s disease (AD) and vascular dementia (VaD). METHODS: The study included 64 AD patients, 72 VaD patients, and 56 healthy controls (HC). Plasma Fg level was detected by turbidimetry. Among the participants, 64 AD patients, 52 VaD patients, and 56 HC underwent FGB −148C/T polymorphism analysis using restriction fragment length polymorphism-PCR. RESULTS: Plasma Fg was significantly higher in AD and VaD groups than in HC. The AD and VaD patients with FGB −148 TT genotype had significantly higher plasma Fg than those with CC or CT genotypes. The distribution of CC and CT+TT genotypes differed in the three groups, with the frequency of CT+TT genotypes being higher in AD patients than in the HC group. CONCLUSIONS: Plasma Fg level was significantly correlated with AD and VaD and related to the −148C/T polymorphism of FGB. The TT+CT genotypes and the distribution frequency of the T allele may be related to AD.