World Hypertension Day - Can't cure your blood pressure? Genetic testing can help you "win the battle"

Hypertension is known as the "silent killer". Sustained hypertension can cause damage to multiple organs, including the heart, brain, kidneys and blood vessels throughout the body, and then induce stroke, myocardial infarction, coronary heart disease, heart failure, renal failure, etc. Its disability and mortality rates are relatively high. Effectively controlling blood pressure levels can prevent the occurrence of serious complications of hypertension, so it is particularly important to choose safe and effective treatment drugs.

ØHave you chosen the right antihypertensive medicine ?

Once hypertension is diagnosed, in addition to adjusting diet and lifestyle, the use of antihypertensive drugs is essential. Have you ever experienced unstable blood pressure control, severe adverse drug reactions, and repeated attempts on yourself but still unable to lower your blood pressure? That may be because the antihypertensive drug is not selected correctly. Only by choosing the right antihypertensive drug can blood pressure be effectively controlled and adverse reactions be minimized. So how can we shorten the road of repeated attempts and twists and turns in choosing antihypertensive drugs? Genetic testing for hypertension drugs may be a sharp weapon that helps you "defeat the enemy with one move."

ØWhat is drug gene testing ?

In clinical practice, we often find that different patients respond differently to the same drug, which is related to individual differences among patients, including the patient's own physical condition, external environmental factors, and genetic factors. A large number of studies have shown that genetic factors are an important cause of individual differences in drug responses.

After entering the body, drugs need to be absorbed, distributed, metabolized, and cleared. In this process, transporters responsible for drug transport, metabolic enzymes responsible for metabolism, and related proteins of drug receptors are involved. The polymorphism of the genes encoding these proteins can seriously affect the metabolic rate, blood drug concentration, and drug sensitivity of the drug, thereby showing different drug effects and side effects [1]. Drug gene testing can detect the genotype of the patient's drug-related genes, and then predict the therapeutic effect of the patient's use of this drug. Combined with the patient's clinical information, it can guide doctors to choose the best drug treatment plan for each patient's specific situation.

ØGene testing for hypertension drugs**** Customize your medication plan

With the in-depth study of pharmacogenetics in recent years, the correlation between drug efficacy, adverse reactions and genes has gradually become clear. Through genetic testing, the drug-related genotype of the patient can be determined in advance. Combined with the patient's other conditions, the doctor can tailor a medication plan for the patient, which can avoid the risk of adverse reactions and waste of medical resources caused by repeated drug trials [2]. Genetic testing technology has gradually matured in the drug treatment of hypertension. The latest "Guidelines for Rational Use of Hypertension Drugs" clearly states that the impact of pharmacogenomics should be considered when using antihypertensive drugs. Genetic testing can guide clinicians to select appropriate antihypertensive drugs and dosages for specific patients to improve the effectiveness and safety of antihypertensive drug treatment.

There are many types of drugs for the treatment of hypertension, and different drugs correspond to different genotypes, generally including CYP2D6, ADRB1, CYP2C9, AGTR1, ACE, etc. [3]. Differences in genotypes lead to different drug metabolism rates, which in turn affect the effectiveness and safety of drug treatment. Understanding the patient's genotype can help adjust the patient's medication or dosage in a targeted manner.

ØWhere can I get genetic testing for hypertension drugs?

At present, the Pharmacogenomics Laboratory of Beijing Chaoyang Hospital affiliated to Capital Medical University has launched a hypertension drug gene testing project, which can help you know your hypertension drug genotype and obtain a customized individualized hypertension medication plan based on it, so as to help you find the most suitable antihypertensive drug for yourself as soon as possible. This project is tested once, and the benefits will last a lifetime, and it can be reimbursed by medical insurance. You can go to the cardiology department, neurology department, vascular surgery department, pharmacy department and other departments to order this test project.

ØClinical application cases of gene testing for hypertension drugs

Mr. Wang, a patient with a 5-year history of hypertension, recently visited the doctor due to elevated blood pressure. The doctor adjusted the antihypertensive regimen to 50 mg qd of losartan tablets (Cozaar). After 2 weeks of use, the patient's blood pressure was still poorly controlled. The patient visited the doctor again. This time, the doctor prescribed a genetic test for hypertension drugs for the patient. The results showed that the patient's CYP2C9*3 was a heterozygous mutation (1/3), and the AGTR1 gene locus was wild type (AA), indicating that the patient's metabolic enzyme activity was low, but the receptor sensitivity was normal . Because losartan needs to be metabolically activated by this enzyme, this means that the effective blood concentration of losartan tablets taken by this patient is low, resulting in poor efficacy. Other sartan drugs need to be metabolically inactivated by this enzyme, and the reduction of this enzyme activity can lead to a higher blood concentration, and a small dose can be used to exert its effect. Therefore, the doctor adjusted the medication regimen to ** irbesartan (Ambovi) 75 mgqd . After 2 weeks of treatment, the patient's blood pressure was well controlled.

Pharmaceutical Tips: CYP2C9 activates losartan and inactivates other sartan drugs . Patients with the 3/3 genotype have a low ability to activate losartan and need to increase the dose or replace other drugs to enhance the antihypertensive effect; however, they are sensitive to irbesartan and valsartan, and a small dose may achieve clinical efficacy. A larger dose requires vigilance against the risk of adverse drug reactions.

References

[1] Rysz, J., Franczyk, B., Rysz-Górzyńska, M., & Gluba-Brzózka, A. (2020). Pharmacogenomics of Hypertension Treatment. International journal of molecular sciences, 21(13), 4709.

[2] Hockings, JK, Pasternak, AL, Erwin, AL, Mason, NT, Eng, C., & Hicks, JK (2020). Pharmacogenomics: Anevolving clinical tool for precision medicine. Cleveland Clinic journal of medicine, 87(2), 91–99.

[3] “Technical Guidelines for Drug Metabolizing Enzymes and Drug Target Gene Detection (Trial) 2015”.