Decreased high-density lipoprotein cholesterol and serum apolipoprotein AI concentrations are highly correlated with the severity of Alzheimer's disease.

Serum apolipoprotein (apo) AI concentration was studied in 98 Alzheimer's disease (AD) patients (77.56+/-8.83 years) and 59 healthy, elderly controls (75.37+/-5.27 years). ApoAI levels were significantly lower (p<10(-7)) in AD patients. An apoAI cutoff value of 1.50 g/L, could distinguish between the two groups with a sensitivity of 71% and a specificity of 69%. ApoAI levels were highly correlated with mini-mental state (MMSE) scores of patients (p<0.0001). These relationships remained significant after adjustment for multiple testing. Our findings raise the question of the potential implication of apoAI in the etiopathology of AD and bring serum apoAI concentration to the fore as an important biochemical marker.