Association of inflammatory markers and lipoprotein particle subclasses with progression of coronary artery calcium: The multi-ethnic study of atherosclerosis.

BACKGROUND AND AIMS

Atherosclerosis is a complex phenomenon manifesting several features typical of chronic inflammation and disorders of lipid metabolism. We assessed association of nuclear magnetic resonance (NMR) lipid variables and inflammatory markers with incident coronary artery calcium (CAC) and CAC progression among participants with baseline CAC ≥0.

METHODS

MESA is a longitudinal cohort study of 6,814 participants (aged 45-85). 3,115 had CAC = 0 and 2,896 had CAC>0 at baseline. Repeat CAC measurements were obtained (mean duration of follow up, 6.5 years).

RESULTS

IL-6 (log pg/mL) and fibrinogen (50 mg/dL) were associated with a higher relative risk (RR) of incident CAC (HU) (RR = 1.09, p=0.010 & RR 1.05, p=0.004, respectively). Small LDL (100 nmol/L) (RR = 1.03, p<0.001) and log large VLDL (log nmol/L) (RR = 1.06, p=0.001) were associated with higher risks, whereas large HDL (μmol/L) was associated with an inverse risk of incident CAC (RR = 0.97, p< 0.001) in a model adjusted for follow up time, age, gender and race. Among participants with baseline CAC>0, progression of CAC was positively associated with hsCRP (log mg/L) (β = 1.99), IL-6 (log pg/mL) (β = 2.9), fibrinogen (50 mg/dL) (β = 1.0), large VLDL (log nmol/L) (β = 2.2), and small LDL (100 nmol/L) (β = 0.36) (all p values < 0.05) in a model adjusted for scanner type, age, gender and race. Relationships with inflammatory markers and NMR lipoprotein particles lost significance after adjustment for traditional risk factors and statin use. Traditional risk factors were strongly associated with both CAC incidence and progression with the exception of cholesterol parameters not associated with CAC progression in adjusted model.

CONCLUSIONS

Inflammatory markers and lipoprotein particles were associated with CAC incidence and progression in minimally adjusted models, but not after adjustment for traditional risk factors.