Ischemic stroke and myocardial ischemia in clopidogrel users and the association with CYP2C19 loss-of-function homozygocity: a real-world study

Differences in the Proportion of CYP2C19 Loss-of-Function Between Cerebral Infarction and Coronary Artery Disease Patients

Background

Cytochrome P450 2C19 (CYP2C19) genotypes and metabolic phenotypes (extensive metabolizer (EM), intermediate metabolizer (IM), and poor metabolizer (PM)) are related to the metabolism of therapeutic drugs for cardiovascular and cerebrovascular diseases. This study aimed to investigate the differences of CYP2C19 gene polymorphism distribution between coronary artery disease (CAD) patients and cerebral infarction (CI) patients.

Methods

We identified 413 CI patients, 509 CAD patients, and 241 CI+CAD patients from 2016 to 2020 and studied genotypes of CYP2C19 rs4986893 (636G>A) and rs4244285 (681G>A) polymorphisms using PCR-gene chip detection method. Differences in CYP2C19 genotypes and metabolic phenotypes between the groups were compared. To analyze the efficacy of CYP2C19 metabolic phenotypes in discriminating between cerebral infarction and coronary artery disease, multiple logistic regression analysis was conducted after adjusting for gender, age, smoking history, drinking history, hypertension, and diabetes.

Results

There were significant differences in the distribution of CYP2C19 genotypes and metabolic phenotypes between CI and CAD patients. The results of multivariate logistic regression (adjusted for sex, age, smoking, drinking, hypertension, and diabetes) indicated that CYP2C19 IM phenotype (IM vs EM: OR 1.443, 95% CI: 1.086-1.918, P=0.011) and CYP2C19 IM+PM phenotype (IM or PM vs EM: OR 1.440, 95% CI: 1.100-1.885, P=0.008) may be indicators of CI from CAD.

Conclusion

CYP2C19 EM metabolic phenotype was dominant in CAD patients, and CYP2C19 IM metabolic phenotype was dominant in CI patients. After adjusting for other confounding factors, patients with the CYP2C19 IM metabolic phenotype were more likely to develop CI than CAD.

The Influence of Pharmacogenetics on the Clinical Relevance of Pharmacokinetic Drug-Drug Interactions: Drug-Gene, Drug-Gene-Gene and Drug-Drug-Gene Interactions

Drug interactions are a well-known cause of adverse drug events, and drug interaction databases can help the clinician to recognize and avoid such interactions and their adverse events. However, not every interaction leads to an adverse drug event. This is because the clinical relevance of drug-drug interactions also depends on the genetic profile of the patient. If inhibitors or inducers of drug metabolising enzymes (e.g., CYP and UGT) are added to the drug therapy, phenoconcversion can occur. This leads to a genetic phenotype that mismatches the observable phenotype. Drug-drug-gene and drug-gene-gene interactions influence the toxicity and/or ineffectivness of the drug therapy. To date, there have been limited published studies on the impact of genetic variations on drug-drug interactions. This review discusses the current evidence of drug-drug-gene interactions, as well as drug-gene-gene interactions. Phenoconversion is explained, the and methods to calculate the phenotypes are described. Clinical recommendations are given regarding the integratation of the PGx results in the assessment of the relevance of drug interactions in the future.