The role of sex, age and genetic polymorphisms of CYP enzymes on the pharmacokinetics of anticholinergic drugs

Development of two ultra-sensitive UHPLC-QqQ-MS/MS methods for the simultaneous determination of hydroxyzine and its active metabolite (cetirizine) in human blood: applications to real cases of forensic toxicology

Both postmortem toxicological and medical-forensic examinations are very important in the case of analyzing various types of chemical substances. Hydroxyzine (HZ) is a first-generation antihistamine drug with a sedative effect that disrupts cognitive function and affects the ability to drive motor vehicles. Enzymatic oxidation of the hydroxy-methyl group to the carboxyl group leads to the formation of its main metabolite-cetirizine (CZ). CZ is the active substance of antiallergic drugs. Because it does not cross the BBB (blood-brain barrier) easily, it is less likely to cause drowsiness or affect memory and impair cognitive function. Therefore, in criminal studies, it is often important what medication had been taken by a person involved, e.g., in a car accident, HZ or CZ. The analysis of both antihistamine drugs is challenging, as usually very low concentrations of the compound of interest need to be determined. Thus, an ultra-sensitive UHPLC-QqQ-MS/MS method was developed for simultaneous determination of HZ and CZ in biological fluid samples. The lower limit of quantification (LOQ) for HZ and CZ was calculated as 0.345 and 0.3696 ng/mL, respectively. Together with a reduced sample volume to 200 μL, it makes the developed method suitable for a sensitive multidrug forensic toxicological analysis. Samples were extracted with simple and fast liquid-liquid extraction (ethyl acetate, pH 9). The present method for the determination of HZ and CZ in human blood proved to be simple, fast, selective, and sensitive. The quantification by LC-MS/MS was successfully applied to the samples coming from 28 authentic biological fluids (blood, urine, vitreous humor, bile and stomach content), both antemortem and postmortem. The performed studies confirm that the developed method is characterized by a high extraction efficiency. Its accuracy, reproducibility, simplicity, and selectivity suggest its application in clinical, toxicological, and forensic laboratories.

Is Dosage Adjustment Based on Age Necessary for Intravenous Lidocaine in Patients Undergoing General Anesthesia: A Prospective Multi-Arm Comparative Study

It remains unclear whether dosage adjustment of intravenous lidocaine is necessary during general anesthesia for elderly patients over 75 years old. This study aimed to investigate the effects of age on the pharmacokinetics (PK) and safety of intravenous lidocaine in patients undergoing general anesthesia. A total of 599 plasma samples were collected from 76 general anesthesia patients across three age groups: 18-64, 65-74, and ≥ 75 years. Lidocaine was administered intravenously at a dose of 1.5 mg/kg for the 18-64 and 65-74 years groups, while the dose was adjusted to 1.0 mg/kg for the ≥ 75 years group. The plasma concentrations of lidocaine and its active metabolites were measured using a validated ultra-performance liquid chromatography-tandem mass spectrometry assay, and the data were analyzed using a noncompartmental analysis. The results revealed no significant age-related differences in the PK of lidocaine and its metabolites. Among the three age groups, over 90 % of patient achieved a lidocaine concentration within a safe and effective range when the dosage was normalized to 1.5 mg/kg. In conclusion, age-based dosage adjustment was unnecessary for intravenous lidocaine in patients below 86 years undergoing general anesthesia.

The Diversity of CYP2C19 Polymorphisms in the Thai Population: Implications for Precision Medicine

Introduction

CYP2C19 plays a major role in the metabolism of various drugs. The most common genetic variants were the CYP2C19*2 and *3 alleles (rs4244285 and rs4986893, non-functional variants). In previous studies, we found that genetic polymorphisms in CYP2C19 variants influenced the active metabolites of clopidogrel and caused major adverse cardiovascular and cerebrovascular effects. However, the distribution of CYP2C19 varies among ethnic groups and according to adverse drug reactions. This study aimed to investigate the frequency of CYP2C19 genetic polymorphisms in the Thai population and analyze the differences in the frequency of CYP2C19 genetic polymorphisms between Thai and other populations.

Methods

This study enrolled 211 unrelated healthy Thai individuals in total. We performed a real-time polymerase chain reaction to genotype CYP2C19*2 (681G > A) and CYP2C19*3 (636G > A).

Results

In the Thai population, the CYP2C19*1 allele was the most prevalent at 70.14%, while the CYP2C19*2 and *3 alleles were found at frequencies of 25.36% and 4.50%, respectively. Conversely, the CYP2C19*3 allele was not detected in Caucasian, Hispanic, African, Italian, Macedonian, Tanzanian, or North Indian populations. The phenotypic profile of this gene revealed that the frequency of intermediate metabolizers (IMs) is nearly equal to that of extensive metabolizers (EMs), at 42.65% and 48.82% respectively, with genotypes *1/*2 (36.02%) and *1/*3 (6.63%). Likewise, poor metabolizers (PMs) with genotypes *2/*2 (6.16%), *2/*3 (2.37%), and *3/*3 (<1%) are more prevalent in our population as well.

Conclusion

The distribution of CYP2C19 genotype and phenotype influenced by non-functional alleles has potential as a pharmacogenomics biomarker for precision medicine and is dependent on an ethnic-specific genetic variation database.

An Evidence-Based Update on Anticholinergic Use for Drug-Induced Movement Disorders

Drug-induced movement disorders (DIMDs) are associated with use of dopamine receptor blocking agents (DRBAs), including antipsychotics. The most common forms are drug-induced parkinsonism (DIP), dystonia, akathisia, and tardive dyskinesia (TD). Although rare, neuroleptic malignant syndrome (NMS) is a potentially life-threatening consequence of DRBA exposure. Recommendations for anticholinergic use in patients with DIMDs were developed on the basis of a roundtable discussion with healthcare professionals with extensive expertise in DIMD management, along with a comprehensive literature review. The roundtable agreed that "extrapyramidal symptoms" is a non-specific term that encompasses a range of abnormal movements. As such, it contributes to a misconception that all DIMDs can be treated in the same way, potentially leading to the misuse and overprescribing of anticholinergics. DIMDs are neurobiologically and clinically distinct, with different treatment paradigms and varying levels of evidence for anticholinergic use. Whereas evidence indicates anticholinergics can be effective for DIP and dystonia, they are not recommended for TD, akathisia, or NMS; nor are they supported for preventing DIMDs except in individuals at high risk for acute dystonia. Anticholinergics may induce serious peripheral adverse effects (e.g., urinary retention) and central effects (e.g., impaired cognition), all of which can be highly concerning especially in older adults. Appropriate use of anticholinergics therefore requires careful consideration of the evidence for efficacy (e.g., supportive for DIP but not TD) and the risks for serious adverse events. If used, anticholinergic medications should be prescribed at the lowest effective dose and for limited periods of time. When discontinued, they should be tapered gradually.

Polypharmacy, drug-drug interactions, anticholinergic burden and cognitive outcomes: a snapshot from a community-dwelling sample of older men and women in northern Italy

Polypharmacy (PP) use is very common in older people and may lead to drug-drug interactions (DDIs) and anticholinergic burden (ACB) that may affect cognitive function. We aimed to determine the occurrence of PP, potential DDIs and ACB and their role in cognitive outcomes in an older population. Cross-sectional data from 636 community-dwelling adults (73.2 ± 6.0 SD, 58.6% women) participating in the NutBrain study (2019-2023) were analyzed. Participants were asked about their medication use, and data on potential DDIs and ACB were extracted. The associations of PP (≥ 5 drugs/day), potential DDIs, and ACB with mild cognitive impairment (MCI) and specific cognitive domains were assessed using logistic regression adjusted for confounders. Sex-stratified analysis was performed. Overall, 27.2% of the participants were exposed to PP, 42.3% to potential DDIs and 19% to cumulative ACB. Women were less exposed to PP and more exposed to ACB than men. In multivariate analysis, the odds of having MCI (24%) were three times higher in those with severe ACB (≥ 3) (OR 3.34, 95%CI 1.35-8.25). ACB was positively associated with poor executive function (OR 4.45, 95%CI 1.72-11.49) and specifically with the Frontal Assessment Battery and neuropsychological tests of phonological and semantic fluency. In sex-stratified analysis, ACB was statistically significantly associated with MCI and executive function in women and with memory in men. PP, potential DDIs and anticholinergics use are very common in community-dwelling older people. ACB exposure is associated with MCI, particularly with poor executive function. Clinicians are encouraged to be vigilant when prescribing anticholinergics.Trial registration: Trial registration number NCT04461951, date of registration July 7, 2020 (retrospectively registered, ClinicalTrials.gov).

Outcome differences by sex in oncology clinical trials

Identifying sex differences in outcomes and toxicity between males and females in oncology clinical trials is important and has also been mandated by National Institutes of Health policies. Here we analyze the Trialtrove database, finding that, strikingly, only 472/89,221 oncology clinical trials (0.5%) had curated post-treatment sex comparisons. Among 288 trials with comparisons of survival, outcome, or response, 16% report males having statistically significant better survival outcome or response, while 42% reported significantly better survival outcome or response for females. The strongest differences are in trials of EGFR inhibitors in lung cancer and rituximab in non-Hodgkin's lymphoma (both favoring females). Among 44 trials with side effect comparisons, more trials report significantly lesser side effects in males (N = 22) than in females (N = 13). Thus, while statistical comparisons between sexes in oncology trials are rarely reported, important differences in outcome and toxicity exist. These considerable outcome and toxicity differences highlight the need for reporting sex differences more thoroughly going forward.

Net clinical benefit of clopidogrel versus ticagrelor in elderly patients carrying CYP2C19 loss-of-function variants with acute coronary syndrome after percutaneous coronary intervention

BACKGROUND AND AIMS

Elderly patients with acute coronary syndrome (ACS) tend to choose clopidogrel over potent P2Y12 receptor inhibitor such as ticagrelor after percutaneous coronary intervention (PCI) in China considering higher risks of bleeding. CYP2C19 genotype is regarded as a major factor influencing the efficacy of clopidogrel. The present study aims to investigate the efficacy and safety of ticagrelor relative to clopidogrel in elderly ACS patients after PCI in China with reduced CYP2C19 metabolism.

METHODS

Between January 2016 and March 2019, 2751 ACS patients over 65 years old with CYP2C19 loss-of-function (LOF) variants after PCI were enrolled. All patients were treated with aspirin and P2Y12 receptor inhibitor, among whom 2056 received clopidogrel and 695 received ticagrelor. Net adverse clinical events (NACE), a composite of cardiac death, myocardial infarction (MI), ischemic stroke, target vessel revascularization and clinically relevant bleeding including Bleeding Academic Research Consortium (BARC) types 2, 3, 5 bleeding, were compared between the two groups at 12 months after PCI. Propensity score matching (PSM) was conducted to balance the baseline characteristics between the two groups.

RESULTS

Before and after PSM, NACE was significantly increased in ticagrelor group compared with clopidogrel group at 12 months post PCI (Before PSM, 15.18% vs. 25.61% p<0.001; After PSM, 11.66% vs. 26.01% p<0.001). MACE was comparable between the two groups (Before PSM, 5.45% vs. 5.32% p>0.999; After PSM, 3.59% vs. 5.38% p=0.146). BARC types 2, 3, 5 bleeding events were significantly increased in patients treated with ticagrelor relative to clopidogrel (Before PSM, 10.31% vs. 21.01% p<0.001; After PSM, 8.22% vs. 21.38% p<0.001), which was mainly attributed to a higher incidence of BARC type 2 bleeding events in ticagrelor group (Before PSM, 8.12% vs. 18.56% p<0.001; After PSM, 6.43% vs. 18.83% p<0.001).

CONCLUSIONS

In the present real-world study, selection of ticagrelor over clopidogrel showed a significant increase in NACE with a higher incidence of bleeding and similar ischemic events in elderly ACS patients carrying CYP2C19 LOF variants after PCI.

Relationship between clinical efficacy and plasma concentration-dose ratio of risperidone in patients with schizophrenia

This study aimed to retrospectively explore the relationship between clinical efficacy and plasma concentration-dose ratio of risperidone (RIS) in 252 patients with schizophrenia taking RIS orally. After the same dose of RIS treatment, the plasma concentration of RIS/9-hydroxyrisperidone (9-OH-RIS), the total plasma concentration of RIS, and the ratio of the steady-state plasma concentration to the daily dose of the total active product (C/D) showed individual difference. The RIS plasma concentration was significantly higher in patients taking high doses than those taking lower doses ( P  = 0.003). There was a statistically significant difference in C/D ratio between males and females ( P  = 0.003). There were significant differences in ratio of C/D and the total plasma concentration of RIS between patients under 60 years and over 60 years ( P  = 0.016; P  = 0.005). Logistic regression analysis showed that the therapeutic effect and adverse reactions of RIS were correlated with the ratio of C/D in patients with schizophrenia ( P  = 0.038; P  < 0.001). It has been suggested that the importance of monitoring of the plasma concentration of RIS in patients with schizophrenia and the ratio of C/D may be used as the reference for RIS personalized treatment.

Gender-specific linkages: frailty, polypharmacy, anti-cholinergic burden, and 5-year mortality risk-a real-world analysis

Background

With higher age, frailty escalates the risk of falls, unexpected physical dysfunction, hospitalization, and mortality. Polypharmacy in the older population is a major challenge that not only increases medical costs, but also may worsen the risk of hospitalization and death. More importantly, the properties of anti-cholinergic drugs contribute various negative effects. This study aimed to investigate the sex difference in the association of polypharmacy, anticholinergic burden, and frailty with mortality.

Methods

Participants older than 65 years who attended the geriatric outpatient clinic of the study center between January 2015 and July 2020 were invited to participate in this retrospective study. Comprehensive geriatric assessment data were collected and the phenotype of frailty was determined by Fried's criteria. Cox regression and the Kaplan-Meier curve were used to identify risk factors of 5-year survival along with intergroup differences in the risks.

Results

Of the 2,077 participants, 47.5% were female. The prevalence of frailty and the rate of polypharmacy were 44.7% and 60.6%, respectively. Higher age, male sex, low body mass index, low Mini-Mental State Examination scores, low activities of daily living, frailty status, polypharmacy, and a high Charlson Comorbidity Index score, and greater anticholinergic burden were significant risk factors that were associated with the 5-year all-cause mortality. Male patients with frailty exhibited the highest risks of mortality compared with male patients without frailty and female patients with or without frailty. Polypharmacy was significantly associated with a higher 5-year mortality rate in the frail male group compared with the non-frail male. In frail female group, individuals with a higher anticholinergic burden (as indicated by the Anticholinergic Cognitive Burden Scale) from drug usage exhibited an elevated 5-year mortality rate.

Conclusions

Polypharmacy and greater anticholinergic burden, synergistically interacted with frailty and intensified the 5-year mortality risk in a gender-specific manner. To mitigate mortality risks, clinicians should prudently identify polypharmacy and anticholinergic burden in the older population.

Physiologically based pharmacokinetic (PBPK) modelling of oral drug absorption in older adults - an AGePOP review

The older population consisting of persons aged 65 years or older is the fastest-growing population group and also the major consumer of pharmaceutical products. Due to the heterogenous ageing process, this age group shows high interindividual variability in the dose-exposure-response relationship and, thus, a prediction of drug safety and efficacy is challenging. Although physiologically based pharmacokinetic (PBPK) modelling is a well-established tool to inform and confirm drug dosing strategies during drug development for special population groups, age-related changes in absorption are poorly accounted for in current PBPK models. The purpose of this review is to summarise the current state-of-knowledge in terms of physiological changes with increasing age that can influence the oral absorption of dosage forms. The capacity of common PBPK platforms to incorporate these changes and describe the older population is also discussed, as well as the implications of extrinsic factors such as drug-drug interactions associated with polypharmacy on the model development process. The future potential of this field will rely on addressing the gaps identified in this article, which can subsequently supplement in-vitro and in-vivo data for more robust decision-making on the adequacy of the formulation for use in older adults and inform pharmacotherapy.

CYP2D6 genetic polymorphisms in Saudi systemic lupus erythematosus patients: A cross-sectional study

OBJECTIVES

To determine the prevalence of selected single nucleotide polymorphisms (rs1080985, rs28624811, rs1065852, rs28371725, and rs1135840) in cytochrome P450 2D6 (CYP2D6) gene among Saudi systemic lupus erythematosus (SLE) patients and to investigate the association between the genetic variants and clinical features of SLE.

METHODS

This cross-sectional study was carried out on adult Saudi patients at King Khalid University Hospital, Riyadh, Saudi Arabia. Patients with confirmed SLE based on the 2012 Systemic Lupus International Collaborating Clinics classification criteria were included in the study. Peripheral blood was collected for genomic deoxyribonucleic acid extraction and TaqMan® technologies were used for target genotyping. For statistical analysis, differences in genotype frequencies were determined using the Chi-square test, and the association between the variant genotypes and SLE features was evaluated using logistical regression models.

RESULTS

There were 107 participants included in this study. Overall, the most predominant (23.4%) recessive genotype was AA in rs28624811, and the least prevalent (1.9%) recessive genotype was TT in rs28371725. Moreover, the variant rs1080985 genotypes (GC or CC) were significantly associated with the presence of serositis manifestation (OR=3.15, p=0.03), even after adjusting for age and gender. However, the dominant rs28624811 genotype (GG) was associated with renal involvement (OR=2.56, p=0.03).

CONCLUSION

Systemic lupus erythematosus patients carrying CYP2D6 variants might be considered at risk for certain manifestations of SLE. Further studies are needed to investigate the implication of these genetic variations in clinical outcomes and drug response.

The Influence of Acitretin on Brain Lipidomics in Adolescent Mice-Implications for Pediatric and Adolescent Dermatological Therapy

Administration of systemic retinoids such as acitretin has not been approved yet for pediatric patients. An adverse event of retinoid-therapy that occurs with lower prevalence in children than in adults is hyperlipidemia. This might be based on the lack of comorbidities in young patients, but must not be neglected. Especially for the development of the human brain up to young adulthood, dysbalance of lipids might be deleterious. Here, we provide for the first time an in-depth analysis of the influence of subchronic acitretin-administration on lipid composition of brain parenchyma of young wild type mice. For comparison and to evaluate the systemic effect of the treatment, liver lipids were analogously investigated. As expected, triglycerides increased in liver as well as in brain and a non-significant increase in cholesterol was observed. However, specifically brain showed an increase in lyso-phosphatidylcholine and carnitine as well as in sphingomyelin. Group analysis of lipid classes revealed no statistical effects, while single species were tissue-dependently changed: effects in brain were in general more subtly as compared to those in liver regarding the mere number of changed lipid species. Thus, while the overall impact of acitretin seems comparably small regarding brain, the change in individual species and their role in brain development and maturation has to be considered.

Relevance of sex-differenced analyses in bioenergetics and nutritional studies

Sex-biased analyses still remain as one of the biggest limitations to obtain universal conclusions. In biomedicine, the majority of experimental analyses and a significant amount of patient-derived cohort studies exclusively included males. In nutritional and molecular medicine, sex-influence is also frequently underrated, even considering maternal-inherited organelles such as mitochondria. We herein illustrate with in-house original data examples of how sex influences mitochondrial homeostasis, review these topics and highlight the consequences of biasing scientific analyses excluding females as differentiated entities from males.

Characterization of LC-MS based urine metabolomics in healthy children and adults

Previous studies reported that sex and age could influence urine metabolomics, which should be considered in biomarker discovery. As a consequence, for the baseline of urine metabolomics characteristics, it becomes critical to avoid confounding effects in clinical cohort studies. In this study, we provided a comprehensive lifespan characterization of urine metabolomics in a cohort of 348 healthy children and 315 adults, aged 1 to 78 years, using liquid chromatography coupled with high resolution mass spectrometry. Our results suggest that sex-dependent urine metabolites are much greater in adults than in children. The pantothenate and CoA biosynthesis and alanine metabolism pathways were enriched in early life. Androgen and estrogen metabolism showed high activity during adolescence and youth stages. Pyrimidine metabolism was enriched in the geriatric stage. Based on the above analysis, metabolomic characteristics of each age stage were provided. This work could help us understand the baseline of urine metabolism characteristics and contribute to further studies of clinical disease biomarker discovery.

Clinical Effectiveness of Muscarinic Receptor-Targeted Interventions in Neuropsychiatric Disorders: A Systematic Review

BACKGROUND

For decades, treatment of mood disorders, psychoses, anxiety and dementia have been confounded by limited efficacy and high rates of treatment resistance. Preclinical and clinical evidence have highlighted disruption of cholinergic signalling in several neuropsychiatric conditions and examined intervention strategies including acetylcholinesterase inhibitors and nicotinic receptor-targeted intervention. However, the effectiveness of these approaches is often curtailed by on-target side effects. Post mortem studies implicate muscarinic receptor dysregulation in neuropsychiatric pathophysiology; therefore, we conducted a systematic review and meta-analysis to investigate the therapeutic efficacy and safety of muscarinic receptor-targeted interventions in adults with neuropsychiatric disorders.

METHODS

PubMed, EMBASE, PsycINFO, EBSCO and Web of Science were searched using relevant keywords from database inception to 7 August 2022. Randomised, double-blind, placebo-controlled studies were included if they investigated the effect of muscarinic receptor-targeted intervention in adults with a diagnosis of a neuropsychiatric disorder and were published in English. A narrative synthesis approach was adopted to describe the findings. Wherever three or more studies with a similar intervention were available, effect sizes were calculated, and a meta-analysis was performed. Cochrane risk-of-bias-2 tool was utilised to assess the risk of bias, and sensitivity analyses were performed to identify publication bias. Certainty analysis (high, moderate, low and/or very low) was conducted using GRADE criteria.

RESULTS

Overall, 33 studies met the inclusion criteria and 5 were included in the meta-analysis. Despite a limited pool with several different interventions, we found therapeutic efficacy of xanomeline (M₁/M₄ agonist) in primary psychotic disorders plus behavioural and psychological symptoms of dementia. Scopolamine showed a significant antidepressant effect in a combined cohort of major depressive and bipolar disorders in the short-term outcome measure, but no effect following cessation of treatment. Results from bias assessments suggest "very low" certainty in the antidepressant effect of scopolamine. Critical limitations of the current literature included low power, high heterogeneity in the patient population and a lack of active comparators.

CONCLUSION

While the results are not definitive, findings on muscarinic receptor-targeted interventions in several mental disorders are promising in terms of efficacy and safety, specifically in treating schizophrenia, mood disorders, and behavioural and psychiatric symptoms of Alzheimer's disease. However, orthosteric muscarinic receptor-targeted interventions are associated with a range of peripheral adverse effects that are thought to be mediated via M₂/M₃ receptors. The orthosteric binding site of muscarinic acetylcholine receptors is remarkably conserved, posing a challenge for subtype-selective interventions; nonetheless allosteric ligands with biased signalling pathways are now in development. We conclude that adequately powered prospective studies with subtype-selective interventions are required to determine the clinical effectiveness of muscarinic-receptor targeted interventions for the treatment of neuropsychiatric disorders.