@Article{ecn.2010.0213,
AUTHOR = {Bartosz Hudzik, Janusz Szkodzinski, Aleksander Danikiewicz, Krzysztof Wilczek, Wojciech Romanowski, Andrzej Lekston, Lech Polonski, Barbara Zubelewicz-Szkodzinska},
TITLE = {Effect of omeprazole on the concentration of interleukin-6 and transforming growth factor-β1 in patients receiving dual antiplatelet therapy after percutaneous coronary intervention},
JOURNAL = {European Cytokine Network},
VOLUME = {21},
YEAR = {2010},
NUMBER = {4},
PAGES = {257--263},
URL = {http://www.techscience.com/ECN/v21n4/65843},
ISSN = {1952-4005},
ABSTRACT = {Background. Dual antiplatelet therapy (aspirin plus clopidogrel) is recommended in patients
undergoing percutaneous coronary intervention (PCI). Treatment with proton pump inhibitors (PPIs) decreases
bleeding rate. Alarming reports have been made that PPIs may decrease the antiplatelet activity of clopidogrel.
We sought to determine whether levels of interleukin-6 (IL-6) and transforming growth factor-β1 (TGF-β1)
might help distinguish individuals at risk for adverse events. Methods. Thirty-eight patients on aspirin and
clopidogrel were enrolled and divided into two groups: group 1 [patients receiving omeprazole (n = 18)] and
group 2 [patients not receiving omeprazole (n = 20)]. Patients underwent PCI and were scheduled for twelve-month
clinical follow-up. The major, adverse cardiac and cerebrovascular events (MACCE) include death,
re-hospitalization for acute coronary syndromes, and stroke. Results. Median concentrations of IL-6 were
higher in group 1 at 4.7 pg/mL, in comparison with group 2, 1.65 pg/mL (p = 0.003). Median concentrations of
TGF-β1 were similar in both groups (p = 0.5). Patients in group 1 had a significantly higher leukocyte count
[10<sup>3</sup>/mm<sup>3</sup>
 ] (median 7.5 vs 6.5; p = 0.04). There were no deaths during follow-up. The incidence of myocardial
infarction was higher in group 1 (33.4% vs 5.0%; p = 0.03). MACCE at twelve months were more frequent in
group 1 (55.6% vs 20.0%; p = 0.02). The cut-off value to predict MACCEs for IL-6 was > 3.6 pg/mL (sensitivity
64%, specificity 88%, positive predictive value 75%, negative predictive value 81%). Interpretation. We show
here that concomitant omeprazole use is associated with an increased inflammatory reaction. Drug interactions
may reduce the anti-inflammatory effect of clopidogrel. This mechanism maybe responsible for an increased
risk of non-fatal, cardiovascular events, following stent placement.},
DOI = {10.1684/ecn.2010.0213}
}