Levels of blood proteins may help decide the course of treatment for people with coronary artery disease (CAD), according to the results of two preliminary studies. CAD occurs when fatty deposits narrow the arteries that supply blood to the heart, and can lead to chest pain and heart attack.
In the first study, researchers identified interleukin-6 (IL-6), an immune system protein that plays a role in inflammation, as a risk factor for death from CAD.They suggest that patients with elevated levels of IL-6 may be candidates for early surgical intervention. Overall, patients with higher levels of IL-6 were more likely to die than those with lower levels. And while surgery reduced mortality by about 5% in the patients with high IL-6 levels, it had no effect on mortality among those with lower levels of the protein.
In the second study, researchers report that another blood protein associated with immune response called myeloperoxidase (MPO) is associated with CAD. If these findings are confirmed in other populations and prove to be predictive of coronary events, MPO levels may be helpful to identify patients with CAD who might otherwise not be identified by routine screening methods.
Despite the interesting observations in these studies, major questions need to be resolved before measurements of blood proteins are incorporated into the routine assessment of patients with CAD.