High apoB/apoA-I ratio is associated with increased progression rate of carotid artery intima-media thickness in clinically healthy 58-year-old men: experiences from very long-term follow-up in the AIR study.
OBJECTIVE
The aim of the present study was to investigate the relationship between atherosclerotic progression rate as measured by carotid artery IMT during very long-term follow-up in clinically healthy men and a number of baseline risk factors of potential importance for atherosclerosis progression including apoA-I, apoB, apoB/apoA-I ratio, other lipid variables including LDL particle size, body composition variables, blood pressure, smoking, fasting blood glucose and insulin, and also hsCRP.


BACKGROUND
Low-density lipoprotein (LDL) is associated with increased carotid IMT progression rate during long-term follow-up, whereas the relationship between newer biomarkers such as apoB/apoA-I ratio and carotid artery IMT progression rate has been less investigated.


METHODS
58-year-old men identified by screening in the community (n=391) with varying degrees of obesity and insulin sensitivity were examined with high-resolution B-mode ultrasound at baseline and after 3, and 8.9 years of follow-up (n=305 investigated after 8.9 years). The carotid arteries were examined bilaterally, and the mean intima-thickness was calculated for 10mm sections of the composite of common carotid arteries and bulbs (IMT(composite)). Serum levels of apoB and apoA-I were measured using a turbidimetric method. Uni- and multi-variable analyses were performed to study the relationship between carotid IMT(composite) progression rate and risk factors.


RESULTS
In a multi-variable analysis including all baseline variables only the apoB/apoA-I ratio (p=0.003; beta=0.181, standard error=0.003) and serum insulin (p=0.026; beta=-0.133, standard error=0.000) was significantly related to IMT(composite) progression rate.


CONCLUSIONS
The results indicate that apoB/apoA-I ratio is an important risk factor for predicting atherosclerotic progression rate during very long-term follow-up in clinically healthy middle-aged men.
Schmidt
C
C
The Wallenberg Laboratory for Cardiovascular Research, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden. caroline.schmidt@wlab.gu.se
Wikstrand
J
J
D016632:Apolipoprotein A-I / Q000097:blood*; D001055:Apolipoproteins B / Q000097:blood*; D050197:Atherosclerosis / Q000097:blood* / Q000175:diagnosis; D001786:Blood Glucose / Q000378:metabolism; D002097:C-Reactive Protein / Q000378:metabolism; D002339:Carotid Arteries / Q000473:pathology*; D018450:Disease Progression; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012307:Risk Factors; D017539:Tunica Intima / Q000473:pathology*; D017540:Tunica Media / Q000473:pathology*
D016632:Apolipoprotein A-I; D001055:Apolipoproteins B; D001786:Blood Glucose; D002097:C-Reactive Protein