Objective: ApoB exerts a pro-thrombotic and pro-atherogenic effect and promotes the progression of atherosclerotic lesions. In the present study, we investigated if elevated ApoB serum levels predicted the risk of premature cardiovascular events in a prospective Swedish cohort study of 60-year-old men and women from Stockholm.
Design: A cohort consisting of every third man and woman turning 60 years of age in the large Stockholm area during the years 1997-1998 (n=4232).
Methods: Incident cases of cardiovascular diseases have been recorded yearly by matching national registries. Exposure to high ApoB serum levels (≥0.9 g/l) was used to calculate the risk of cardiovascular diseases, and the time to the first cardiovascular event using Cox regression and Laplace regression, respectively.
Results: Individuals exposed to high ApoB serum levels showed an increased risk of cardiovascular diseases over the 11 years of follow-up. The HR decreased over time from 2.49 at 4 years of study entry (95% CI 1.31 to 4.69) to 1.36 at 11 years (95% CI 1.01 to 1.83), after adjusting for gender, diabetes, hypertension, smoking, obesity, HDL and triglyceride serum levels. The first 5% of the individuals had a cardiovascular event nearly 2 years earlier among those with ApoB ≥0.9 g/l than among those with ApoB <0.9 g/l (p=0.001).
Conclusions: Our data indicate that increased ApoB serum levels are important predictors of early cardiovascular events. It is possible that this reflects a shift over time in the effects of apoB from a more pro-thrombotic to a more pro-atherogenetic molecule.