Apolipoprotein B Level and the Apolipoprotein B/Apolipoprotein A-I Ratio as a Harbinger of Ischemic Stroke: A Prospective Observation in Taiwan

Aim: Prospective studies indicate that apolipoprotein (apo) measurements predict coronary heart disease risk. However, few population-based follow-up studies have addressed the predictive value of apo measurements in stroke risk. The aims of the present study were to analyze the predictive ability of apo measurements in the risk of ischemic stroke. Methods: Serum apo A-I and apo B levels and calculated apo B/apo A-I ratio were measured at baseline in 2002 in a cohort of 4,204 participants who were followed for a mean of 4.61 years for a stroke event. Results: After adjustment for potential confounders, a significantly stepwise increase in the incidence rate of stroke across quartiles of both apo B and the apo B/apo A-I ratio was evident in both genders and across age-groups. The predictive ability of apo B to detect ischemic stroke was comparable with that of the apo B/apo A-I ratio. Furthermore, both apo B and the apo B/apo A-I ratio were better predictors of the risk of ischemic stroke than total cholesterol (TC), low-density lipoprotein cholesterol, and the TC/high-density lipoprotein cholesterol ratio. Conclusions: This cohort study demonstrates that apo B and the apo B/apo A-I ratio were a significant risk predictor of stroke. Furthermore, the predictive ability of apo B and the apo B/apo A-I ratio in stroke risk was better than routine clinical lipid measurements. Thus, measurements of apolipoproteins have superior clinical utility over traditional lipid measurements in identifying subjects at risk for ischemic stroke.