Relationship between interleukin 6 and mortality in patients with unstable coronary artery disease: effects of an...

Area of Science:

• Cardiology
• Biomarkers
• Inflammation

Background:

• Inflammatory activity, marked by Interleukin 6 (IL-6), is linked to increased long-term mortality in unstable coronary artery disease (CAD).
• IL-6 influences systemic inflammation markers like C-reactive protein and fibrinogen.

Purpose of the Study:

• To assess if plasma IL-6 levels predict mortality in unstable CAD patients.
• To evaluate the interaction between IL-6 levels and treatment strategies (invasive vs. non-invasive).

Main Methods:

• Prospective, randomized trial (Fragmin and Fast Revascularisation During Instability in Coronary Artery Disease II) involving 3269 unstable CAD patients.
• Random assignment to early invasive or non-invasive strategies, with further randomization to low-molecular-weight heparin (dalteparin) or placebo.
• Measurement of plasma IL-6 levels at randomization to assess 6- and 12-month mortality.

Main Results:

• Plasma IL-6 levels ≥ 5 ng/L were associated with significantly increased mortality in non-invasive and placebo groups.
• An early invasive strategy reduced 12-month mortality in patients with elevated IL-6 (absolute reduction 5.1%, P=.004).
• Dalteparin treatment showed a trend towards lower 6-month mortality in patients with elevated IL-6 (absolute reduction 3.5%, P=.08).

Conclusions:

• Circulating IL-6 is an independent predictor of increased mortality in unstable CAD.
• Elevated IL-6 levels identify patients who derive the greatest benefit from early invasive management.