Interleukin-3 is elevated in patients with coronary artery disease and predicts restenosis after percutaneous coronary intervention

BACKGROUND: Interleukin-3 (IL-3) synthesized by activated T-lymphocytes is a mediator in chronic inflammation and is suspected to promote atherosclerosis. Since there is no data on IL-3 in patients with coronary artery disease (CAD) available, we compared IL-3 concentrations in different subsets of patients with CAD to healthy control patients.

METHODS: 205 consecutive patients with CAD, 136 with stable angina and 69 with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention, 61 patients with asymptomatic CAD and 41 patients with normal coronary arteries were investigated. Serum concentrations of IL-3 and hs-CRP were assessed at baseline and after 6 weeks, 6, and 12 months.

RESULTS: In patients undergoing coronary angioplasty, IL-3 was detectable more frequently than in those with asymptomatic CAD or without CAD, 21 vs. 8%, p=0.02, and 21 vs. 1%, p<0.001, respectively. Patients undergoing coronary angioplasty who developed symptomatic restenosis more frequently had detectable IL-3 levels than patients without restenosis, 45 vs. 17%, p=0.02. IL-3 was the only independent predictor for restenosis in a multivariate analysis. Hs-CRP was significantly elevated in patients with ACS, 230+/-170 mg/l vs. 100+/-140 mg/l, p=0.02, but did not correlate with IL-3 concentrations at any time.

CONCLUSION: IL-3, an important regulator of chronic inflammation, is elevated in patients with CAD, particularly in symptomatic patients undergoing percutaneous coronary intervention. Furthermore, high IL-3 concentrations were found to be predictive of symptomatic restenosis.