Sore joints and hard arteries

Patients with mild RA show signs of endothelial dysfunction. Treatment of cardiac risk conditions could help reduce the effects

By Maria Turner

Patients who suffer from rheumatoid arthritis (RA) are at an increased risk of mortality due to cardiovascular disease, according to recent studies. Researchers from the Mayo Clinic found that rheumatoid factor positive (RF+) patients had twice the risk of mortality following myocardial infarction than non-RA controls or RF- patients. About 50% of atherosclerotic coronary artery disease in patients with RA occurs in the absence of conventional cardiovascular risk factors, this according to Dr Gaetano Vaudo, of the University of Perugia, and colleagues. In a study published in the January issue of the Annals of Rheumatic Disease, Dr Vaudo and his fellow researchers found that patients with mild RA but without cardiovascular risk factors showed evidence of endothelial dysfunction - one of the first stages of atherosclerotic disease.

They believe these findings support the view that inflammation may affect endothelial function in RA and provide a basis for the observed epidemiological link between RA and atherosclerotic disease. Dr Vaudo told the National Review of Medicine that treatment of cardiac risk conditions may be a way to improve endothelial function for some RA patients. "Specifically, pharmacological treatment of hypercholesterolemia is known to exert an anti-inflammatory action as well and so lipid lowering treatments, ie statins, may be recommended for RA patients who are also hypercholesterolemic."

He went on to say that the use of infliximab or other new tumour necrosis factor (TNF) inhibitors could also reduce the degree of endothelial function impairment in RA patients being treated by these drugs, but suggested that the most beneficial effects may be obtained by short-term treatments to minimize the negative effect on lipid profile. He added that lifestyle and diet changes could be suggested to favour lipid metabolism in patients receiving TNF-inhibitor therapy.

The study involved 32 patients with RA matched to a control group of 28 patients. Patients with traditional cardiovascular risk factors were excluded from the study. Endothelial function can be tested by looking at the ability of the artery to dilate in response to stimuli. In this study, researchers assessed endothelial function by measuring artery flow-mediated vasodilatation (FMV) in the arm using non-invasive ultrasound. They further tested patients for inflammation markers, erythrocyte sedimentation rate, C-reactive protein (CRP), the presence of rheumatoid factor, triglyceride, homocysteine, HDL, LDL, and total cholesterol levels.

Patients with RA had significantly lower brachial artery FMV, indicative of altered endothelial function, as compared to control patients as well as significantly higher erythrocyte sedimentation rate and CRP levels. Study authors noted that, "Interestingly, the average CRP level multiplied by the disease duration, a marker of the degree of inflammation over the time, was the only predictor of impaired FMV in our patients, along with LDL cholesterol."