Changes of High Sensitivity C-Reactive Protein During Clopidogrel Therapy in Patients Undergoing Percutaneous Coronary Intervention

Background: The crucial role of inflammation in the development and progression of atherosclerosis has been previously described. However, there is insufficient data available to demonstrate the changes in high sensitivity C-reactive protein (hs-CRP) during clopidogrel therapy.

Objectives: In the present study, we aimed to assess the changes in the inflammatory marker of coronary heart disease, i.e., hs-CRP during clopidogrel therapy, in patients undergoing percutaneous coronary intervention (PCI). We also evaluated the anti-inflammatory effects of clopidogrel, if any, in different groups of patients.

Patients and methods: The study population included 650 consecutive patients who underwent elective, urgent, or emergent PCI. Patients received a 300-mg loading dose of clopidogrel (Plavix(®)) and aspirin either 24 hours before the planned PCI, or immediately before the procedure in patients with urgent or emergent PCI, followed by a 75-mg daily maintenance dose for up to 12 weeks. At the end of the 12(th) week, hs-CRP was re-assessed.

Results: Six hundred-fifty patients including 386 (59.4%) male and 264 (40.6%) female subjects were enrolled in the study. The mean hs-CRP level was 15.36 ± 9.83 mg/L with a median of 14 mg/L (interquartile range 8 to 19.6 mg/L). Female, hypertensive, diabetic, and non-smoking patients had higher reductions in hs-CRP in response to clopidogrel therapy compared to male, non-hypertensive, non-diabetic and smoker patients, respectively (all P < 0.005). The changes in the hs-CRP levels were also statistically different in patients with various index events before PCI (P < 0.001). No significant differences were observed in the mean reduction of hs-CRP between the patients without stent implantation and those with bare metal or drug-eluting stents (P = 0.07), respectively.

Conclusions: We found that the use of clopidogrel in patients undergoing PCI had favorable effects on the suppression of hs-CRP. This effect appears to be heightened and more apparent in some group of patients with co-morbidities such as diabetes and hypertension.