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
Received 5 June 2008; received in revised form 17 November 2008; accepted 19 November 2008. published online 05 January 2009.
Abstract
Objectives
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 (IMTcomposite). 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 IMTcomposite progression rate and risk factors.
Results
In a multi-variable analysis including all baseline variables only the apoB/apoA-I ratio (p=0.003; β=0.181, standard error=0.003) and serum insulin (p=0.026; β=−0.133, standard error=0.000) was significantly related to IMTcomposite progression rate.
Conclusion
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.
ABSTRACT