Influence of carriage of genetic variants CYP2D6 * 4 / CYP2D6 * 3 on maximum heart rate when using bisoprolol in patients with acute coronary syndrome

Funding Acknowledgements

Type of funding sources: None.

Introduction

Bisoprolol is one of the most effective and frequently prescribed beta-blockers. The widespread use of bisoprolol is due to its high efficiency in the treatment of patients with various cardiological pathologies: arterial hypertension, ischemic heart disease, chronic heart failure. Bisoprolol, like all members of the group of beta-adrenergic blockers, is effective in the treatment of patients with acute myocardial infarction, reducing the risk of complications such as rhythm disturbances and sudden cardiac death. In vitro studies indicate that bisoprolol is a substrate for two isoforms of cytochrome P450 - 3A4 and 2D6.

Purpose

The purpose of this work was to analyze the effect of CYP2D6 activity on the chronotropic effect of bisoprolol therapy in patients with acute coronary syndrome (ACS).

Materials and methods

The study included patients with ACS who was assigned bisoprolol according to clinical indications. All patients included in the study were Holter monitor on the 10th day of hospitalization - the minimum, mean, maximum heart rate during the day and the maximum heart rate were assessed at the time of exercise was evaluated against the background of the current therapy. All patients included in the study also underwent molecular genetic testing. The detection of polymorphic variants of СYP2D6 (*3/*4) gene was carried out by real-time PCR.

Results

A total of 93 patients, 58 males and 35 females were included in the study. The average age of patients is 63 years.  In the studied population, CYP2D6 * 3 was not detected. The CYP2D6 * 4 mutation occurred with a frequency of 15%, which is comparable to previously published data on the Russian population. The distribution of alleles corresponded to the Hardy-Weinberg law (Chi square, p> 0.05). In order to determine the effect of genetically determined CYP2D6 activity on the effectiveness of bisoprolol therapy in patients with ACS, we identified a group of patients - carriers of the allelic CYP2D6 * 4 variant in homozygous or heterozygous form (AA / AG) (group with a reduced metabolic rate), and a group with the CYP2D6 genotype GG (group with normal and increased metabolic rate). In the correlation analysis, carriage of CYP2D6 * 4 in heterozygous or homozygous form was associated with a lower maximum heart rate during exercise (r-0.21; p <0.05). Maximum heart rate during exercise in carriers of CYP2D6 * 4 was 107 [105; 119], in the comparison group - 114 [108; 120]. The difference was significant with p <0.05 (values are expressed as median [25%; 75%]).

Conclusion

In this study, for the first time, the role of the influence of allelic variants of the CYP2D6 gene on the achievement of maximum heart rate during exercise was revealed when using bisoprolol in patients with ACS. These data may have promising implications for maximizing the personalization of therapy for patients, including those with ACS.

The effect of rs776746 polymorphism in the <i>CYP3A5</i> gene on heart rate when using bisoprolol in patients with acute coronary syndrome

Aim. The aim of this work was to study the occurrence of the rs776746 allelic variant of the CYP3A5 gene and its effect on heart rate (HR) when using bisoprolol in patients hospitalized with acute coronary syndrome (ACS).

Materials and methods. The study included patients with ACS who were prescribed bisoprolol for clinical indications. All patients underwent molecular genetic testing. In order to evaluate the effectiveness of the therapy with bisoprolol, all patients underwent Holter electrocardiogram (ECG) monitoting on days 10, the following parameters were assessed: minimum, average, maximum heart rate and heart rate during an exercise test. The stress test was performed as a ladder test.

Results. The study involved 97 patients (63,5±10,5 years), including 60 men and 37 women. The frequency of occurrence of the desired alleles of the CYP3A5 gene was: CYP3A5*3 - 93%, and CYP3A5*1 - 7%, which corresponds to its prevalence in the European population. 84 carriers of the CYP3A5*3*3 genotype (87%), 12 heterozygous carriers of the *1 allele (12%) and one patient with the *1*1 genotype (1%) were identified. In order to search for differences in the effects of bisoprolol depending on the genetically predetermined activity of CYP3A5, we divided the general group of patients into two subgroups: subgroup 1 (CYP3A5*3*3), represented by carriers of the genotype associated with the synthesis of the inactive form of CYP3A5, and subgroup 2 (CYP3A5*1*3 and CYP3A5*1*1), represented by carriers of at least one allele encoding the synthesis of a fully functional protein CYP3A5, coupled with an increased metabolic rate. Patients did not differ in clinical and demographic characteristics. By the time of daily ECG monitoring, both groups reached comparable heart rate values. In carriers of at least one CYP3A5*1 allele (n = 13), associated with an increased metabolic rate, the daily dose of bisoprolol on the 10th day of hospitalization was significantly higher (p <0.05). The only carrier of the homozygous CYP3A5 *1*1 variant receives bisoprolol at a daily dose of 10 mg. Taking into account the close to significant differences in glomerular filtration rate (GFR) in patients in the groups with the studied genetic variants, and the known eliminating role of the kidneys for bisoprolol, a linear regression model was built with the inclusion of factors that could affect the dose of bisoprolol: GFR, functional class of chronic heart failure, gender, age, number of simultaneously assigned CYP3A5 substrates. Of the parameters listed, only the CYP3A5 genotype significantly predicted the dose of bisoprolol (F=8.5; p<0.005; R2=0.096).

Conclusion. In this study, it was demonstrated for the first time that patients with different genetic variants of CYP3A5, in particular with respect to the rs776746 polymorphism, may differ in individual requirements for the dose of bisoprolol.

Syndrome of senile asthenia and anxiety-depressive disorders in elderly patients with acute coronary syndrome

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Northwestern State Medical University named after I.I. Mechnikov

Introduction. The syndrome of senile asthenia (ASA) ("fragility") in combination with anxiety-depressive symptoms in patients contributes to an increase in the frequency of hospitalizations, reduces the effectiveness of treatment and the quality of life. To study the relationship of SSA with anxiety-depressive disorders in elderly patients after acute coronary syndrome (ACS).

Materials and methods. The study included patients with acute coronary syndrome. The inclusion criterion was also a signed voluntary informed consent to participate in the study. A total of 76 patients, 44 men and 32 women hospitalized for ACS were included in this prospective observational study. The average age of the patients is 73.2 years. A questionnaire was conducted with a validated questionnaire "Age is not a hindrance", and the hospital anxiety and depression scale (HADS) was also used.

Results. SSA was found in 32% (p = 0.01) of hospitalized elderly patients, in the majority of women (71%) than men (29%). The average overall score according to the questionnaire "Age is not a hindrance" in elderly patients with ACS was 4.58. The results of the HADS survey showed that anxiety and depressive symptoms in fragile elderly patients occurred in 53.7% and 46.8%, respectively. There was a pronounced relationship between the occurrence of SSA and the symptoms of anxiety according to HADS (p &lt;0.001), however, the more severe depressive symptoms were, the less frequent was SSA (p = 0.007).

Conclusions. "Fragility" in elderly hospitalized patients with ACS is associated with increased anxiety and depressive symptoms. In addition, a significant relationship was demonstrated between high scores on «the age is not a hindrance» questionnaire and the presence of anxiety, but not depression.

[Patient age and CYP2D6*4/CYP2D6*3 genotype on maximal heart rate in patients after acute coronary syndrome treated with bisoprolol.]

We have analyzed influence of genetic variants CYP2D6*3 (2549delA) and CYP2D6*4 (1846G>A), as well as other factors on effects of bisoprolol in patients with acute coronary syndrome. The study included 97 patients with acute coronary syndrome. Mean age was 63±10 years; 60 men and 37 women. We have found association between carriage of CYP2D6*4 (1846G>A) and maximal heart rate at exertion (R-0,21; р<0,05). When the correction for potential confounders was made, age was the only significant predictor of maximal heart rate (β=0,6; SE=0,07; p<0,001). At the same time it was found that CYP2D6*4 was associated with more advanced age of the patients (r=0,2; p<0,05).