Correlation between serum osteoprotegerin and atherosclerotic vascular disorders in rheumatoid arthritis patients

The aim of the present study was to investigate the association of serum osteoprotegerin [OPG] level with the presence of angiographically documented asymptomatic coronary artery disease [CAD] in patients with rheumatoid arthritis [RA] and to evaluate its relationship with plasma thrombomodulin [TM], as a marker of endothelial dysfunction and with carotid artery intima media thickness [IMT], as a marker of atherosclerosis. The study included 20 rheumatoid patients without CAD [negative results on exercise ECG stress test] and other 20 rheumatoid patients with CAD [positive results on exercise ECG stress test and confirmed by coronary angiography]. In addition, 20 age and sex matched normal control subjects were studied. Serum OPG and plasma TM levels were measured and carotid artery IMT was determined. The study revealed that serum OPG levels were significantly higher in rheumatoid patients with and without CAD than in controls [P < 0.001,P < 0.01; respectively] and were positively correlated with age, duration of disease, Disease active score 28[DAS28], Erythrocyte sedimentation rate [ESR], C-reactive protein [CRP] and carotid IMT in rheumatoid patients with and without CAD. Serum OPG level was correlated significantly with plasma TM only in rheumatoid patients with CAD [P < 0.001]. Osteoprotegerin is a clinically important molecule independently associated with the presence of coronary artery disease and may be a good indicator of atherosclerotic vascular damage and macroangiopathy in asymptomatic rheumatoid patients. Hence, measurement of serum OPG merits further investigation as a simple test for improving early diagnosis of asymptomatic CAD in rheumatoid patients