Association between CYP2C9 polymorphisms and ischemic stroke following endovascular neurointervention

Influence of CYP450 Enzymes and ABCB1 Polymorphisms on Clopidogrel Response in Moroccan Patients with Acute Coronary Syndromes

Introduction

Clopidogrel is an antiplatelet prodrug primarily prescribed to prevent or treat acute coronary syndrome (ACS) or acute ischemic stroke (IS), polymorphisms of genes encoding cytochrome P-450 (CYP) and P-glycoprotein transporter, could affect the efficiency of clopidogrel absorption and biotransformation, especially during the first critical hours following its administration.

Methods

The present study was designed to investigate the potential association of clopidogrel responsiveness and 14 polymorphisms in the genes encoding the CYPs (CYP2C9, 2C19, 3A4, 3A5, 1A2, and 2B6), the ATP binding cassette subfamily B member 1 (ABCB1). Platelet aggregation activity was measured after 8h of 300mg clopidogrel administration for fifty-five ACS patients.

Results

There was no significant association between polymorphism of the studied CYPs and clopidogrel responsiveness (P>0.05). The frequency of the ABCB1 3435 T allele in clopidogrel non-responders was higher (78.9%) compared to responders (52.8%), but this difference was not significant (P=0.057). Demographic characteristics, comorbidities, concomitant treatments were not associated with clopidogrel response.

Discussion

There was no effect of the studied genetic variations and demographic factors on the platelet activity of clopidogrel in Moroccan ACS patients.

Independent and Interactive Effects of Sex and CYP2C9 Variant rs4918758 on Ischemic Stroke Risk in Taiwan Biobank

Purpose

Stroke is a complex health condition caused by multiple risk factors. We investigated whether the Cytochrome P450 2C9 (CYP2C9) rs4918758 polymorphism and sex were independently and interactively associated with ischemic stroke risk among Taiwan Biobank (TWB) participants.

Material and Methods

We analyzed TWB data pertaining to 9197 female and 8625 male individuals. Data collected between 2008 and 2015 were linked to medical records in the National Health Insurance Database (NHIRD). Based on multiple logistic regression analyses, we estimated odds ratios (OR) and 95% confidence intervals (CI) for ischemic stroke.

Results

We found that 441 women and 468 men had ischemic stroke. There were no differences in the risk of ischemic stroke between individuals with the TC/CC genotype and those with the TT genotype [OR (95% CI) = 1.04 (0.90–1.21)]. When compared to women, men had an OR of 1.03 (95% CI = 0.87–1.22) for ischemic stroke. Based on further analysis, sex was found to interact with polymorphism rs4918758 (p for interaction = 0.0019). After categorizing by sex, men with TC/CC genotype showed significant ORs but not women [OR (95% CI) = 1.32 (1.07–16.33) vs 0.83 (0.68–1.00)]. Further stratification by genotype showed that in comparison with their female counterparts, men with the TT and TC/CC genotypes had ORs of 0.59 (95% CI = 0.44–0.80) and 1.36 (95% CI = 1.10–1.68), respectively.

Conclusion

According to our study, the TT genotype of rs4918758 was associated with a reduced risk of ischemic stroke in Taiwanese men when compared to women, whereas the TC/CC genotype was associated with a greater risk.

Risk of stroke in CYP2C19 LoF polymorphism carrier coronary artery disease patients undergoing clopidogrel therapy: An ethnicity-based updated meta-analysis

BACKGROUND

Antiplatelet agent clopidogrel has been widely used for stroke management for many years, although resistance to clopidogrel may increase the chance of stroke recurrence. CYP2C19 loss-of-function (LoF) polymorphism is assumed to be responsible for the poor metabolism of clopidogrel that ultimately turns to resistance. Previous publications could not provide firm evidence due to highly conflicting and heterogeneous outcomes.

AIM

To get clear evidence from an updated meta-analysis on CYP2C19 LoF polymorphism association with stroke risk in clopidogrel treated patients, this study has been performed.

METHODS

We conducted a meta-analysis with 72 selected studies from authentic databases, including 40,035 coronary artery disease patients treated with clopidogrel.

RESULTS

This analysis showed that the worldwide carrier of one or more CYP2C19 LoF alleles had a significantly higher risk of stroke and composite events than the non-LoF carriers (RR=1.78, 95% CI=1.52-2.07, p<0.00001 and RR=1.39, 95% CI=1.26-1.54, p<0.00001, respectively). Besides, subgroup analysis showed that Asian CYP2C19 LoF carriers had a significantly increased risk of stroke (RR=1.91, 95% CI=1.60-2.28, p<0.00001) while the risk of composite events was significantly higher in all ethnic populations (Asian: RR=1.58, 95% CI=1.32-1.89, p<0.00001; Caucasian: RR=1.27, 95% CI=1.08-1.50, p=0.003; Hispanic and others: RR=1.21, 95% CI=1.09-1.34, p=0.0003).

CONCLUSION

Our meta-analysis confirmed that the presence of CYP2C19 LoF alleles increases the risk of stroke and composite events recurrence in the worldwide population, especially in Asians undergoing clopidogrel treatment. Alternative antiplatelet therapy should be investigated thoroughly for the intermediate and poor metabolizers.