Evaluation of sexual dimorphism in the efficacy and safety of simvastatin/atorvastatin therapy in a southern Brazilian cohort

A systematic review on sex differences in adverse drug reactions related to psychotropic, cardiovascular, and analgesic medications

Background and objective: Adverse drug reactions (ADRs) are the main safety concerns of clinically used medications. Accumulating evidence has shown that ADRs can affect men and women differently, which suggests sex as a biological predictor in the risk of ADRs. This review aims to summarize the current state of knowledge on sex differences in ADRs with the focus on the commonly used psychotropic, cardiovascular, and analgesic medications, and to aid clinical decision making and future mechanistic investigations on this topic. Methods: PubMed search was performed with combinations of the following terms: over 1,800 drugs of interests, sex difference (and its related terms), and side effects (and its related terms), which yielded over 400 unique articles. Articles related to psychotropic, cardiovascular, and analgesic medications were included in the subsequent full-text review. Characteristics and the main findings (male-biased, female-biased, or not sex biased ADRs) of each included article were collected, and the results were summarized by drug class and/or individual drug. Results: Twenty-six articles studying sex differences in ADRs of six psychotropic medications, ten cardiovascular medications, and one analgesic medication were included in this review. The main findings of these articles suggested that more than half of the ADRs being evaluated showed sex difference pattern in occurrence rate. For instance, lithium was found to cause more thyroid dysfunction in women, and amisulpride induced prolactin increase was more pronounced in women than in men. Some serious ADRs were also found to exert sex difference pattern, such as clozapine induced neutropenia was more prevalent in women whereas simvastatin/atorvastatin-related abnormal liver functions were more pronounced in men.

Neurodegenerative Disease: Roles for Sex, Hormones, and Oxidative Stress

Neurodegenerative diseases cause severe impairments in cognitive and motor function. With an increasing aging population and the onset of these diseases between 50 and 70 years, the consequences are bound to be devastating. While age and longevity are the main risk factors for neurodegenerative diseases, sex is also an important risk factor. The characteristic of sex is multifaceted, encompassing sex chromosome complement, sex hormones (estrogens and androgens), and sex hormone receptors. Sex hormone receptors can induce various signaling cascades, ranging from genomic transcription to intracellular signaling pathways that are dependent on the health of the cell. Oxidative stress, associated with aging, can impact the health of the cell. Sex hormones can be neuroprotective under low oxidative stress conditions but not in high oxidative stress conditions. An understudied sex hormone receptor that can induce activation of oxidative stress signaling is the membrane androgen receptor (mAR). mAR can mediate nicotinamide adenine dinucleotide-phosphate (NADPH) oxidase (NOX)-generated oxidative stress that is associated with several neurodegenerative diseases, such as Alzheimer disease. Further complicating this is that aging can alter sex hormone signaling. Prior to menopause, women experience more estrogens than androgens. During menopause, this sex hormone profile switches in women due to the dramatic ovarian loss of 17β-estradiol with maintained ovarian androgen (testosterone, androstenedione) production. Indeed, aging men have higher estrogens than aging women due to aromatization of androgens to estrogens. Therefore, higher activation of mAR-NOX signaling could occur in menopausal women compared with aged men, mediating the observed sex differences. Understanding of these signaling cascades could provide therapeutic targets for neurodegenerative diseases.

Statin associated adverse reactions in Latin America: a scoping review

OBJECTIVES

We aim to describe the frequency and type of adverse drug reactions (ADRs) in patients on statins in published studies from Latin American (LATAM) countries.

DESIGN

Scoping review.

METHODS

A literature search was conducted in three databases (PubMed, EMBASE and LILACS) in addition to a manual search in relevant journals from LATAM universities or medical societies. A snowballing technique was used to identify further references. Randomised controlled trials (RCTs) and observational studies between 2000 and 2020 were included. Studies were considered eligible if they included adults on statin therapy from LATAM and reported data on ADRs. Data on ADRs were abstracted and presented by study design.

RESULTS

Out of 8076 articles, a total of 20 studies were included (7 RCTs and 13 observational studies). We identified three head-to-head statin RCTs, two statin-versus-policosanol RCTs and only two placebo-controlled trials. The statin-related ADRs frequency ranged from 0% to 35.1% in RCTs and 0% to 28.4% in observational studies. The most common ADRs were muscle-related events including myalgia and elevated creatine phosphokinase. Other reported ADRs were gastrointestinal symptoms, headache and altered fasting plasma glucose.

CONCLUSIONS

We identified differences in the frequency of ADRs in both observational studies and RCTs from LATAM countries. This could be due to the absence of standard definitions and reporting of ADRs as well as differences among the study's interventions, population characteristics or design. The variability of ADRs and the absence of definitions are similar to studies from other geographical locations. Further placebo-controlled trials and real-world data registries with universal definitions should follow.

[18F]Atorvastatin Pharmacokinetics and Biodistribution in Healthy Female and Male Rats

Statins are 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors that are widely used to prevent cardiovascular diseases. However, a series of pleiotropic mechanisms have been associated with statins, particularly with atorvastatin. Therefore, the assessment of [¹⁸F]atorvastatin kinetics with positron emission tomography (PET) may elucidate the mechanism of action of statins and the impact of sexual dimorphism, which is one of the most debated interindividual variations influencing the therapeutic efficacy. [¹⁸F]Atorvastatin was synthesized via a previously optimized ¹⁸F-deoxyfluorination strategy, used for preclinical PET studies in female and male Wistar rats (n = 7 for both groups), and for subsequent ex vivo biodistribution assessment. PET data were fitted to several pharmacokinetic models, which allowed for estimating relevant kinetic parameters. Both PET imaging and biodistribution studies showed negligible uptake of [¹⁸F]atorvastatin in all tissues compared with the primary target organ (liver), excretory pathways (kidneys and small intestine), and stomach. Uptake of [¹⁸F]atorvastatin was 38 ± 3% higher in the female liver than in the male liver. The irreversible 2-tissue compartment model showed the best fit to describe [¹⁸F]atorvastatin kinetics in the liver. A strong correlation (R² > 0.93) between quantitative K_i (the radiotracer’s unidirectional net rate of influx between compartments) and semi-quantitative liver’s SUV (standard uptake value), measured between 40 to 90 min, showed potential to use the latter parameter, which circumvents the need for blood sampling as a surrogate of K_i for monitoring [¹⁸F]atorvastatin uptake. Preclinical assays showed faster uptake and clearance for female rats compared to males, seemingly related to a higher efficiency for exchanges between the arterial input and the hepatic tissue. Due to the slow [¹⁸F]atorvastatin kinetics, equilibrium between the liver and plasma concentration was not reached during the time frame studied, making it difficult to obtain sufficient and accurate kinetic information to quantitatively characterize the radiotracer pharmacokinetics over time. Nevertheless, the reported results suggest that the SUV can potentially be used as a simplified measure, provided all scans are performed at the same time point. Preclinical PET-studies with [¹⁸F]atorvastatin showed faster uptake and clearance in female compared to male rats, apparently related to higher efficiency for exchange between arterial blood and hepatic tissue.

Cholecystectomy and Biliary Sphincterotomy Increase Fecal Bile Loss and Improve Lipid Profile in Dyslipidemia

BACKGROUND AND AIMS

Bile is the only significant pathway for cholesterol elimination. Cholecystectomy (CS) increases fecal bile acid loss, and endoscopic biliary sphincterotomy (ES) is thought to have a similar effect. We speculated that a combined effect of ES + CS would further enhance fecal bile acid loss, potentially causing lipid profile changes in these patients.

METHODS

Fecal bile acids and sterols were determined using gas chromatography in cohorts of post-CS + ES, post-CS and in healthy controls. The effect of ES + CS on blood lipid profile was assessed retrospectively in a single-center cohort of post-CS + ES patients, using a computerized database. Parameters of interest included demographics, medical history, and lipid profiles.

RESULTS

Fecal primary bile acid concentrations were increased after CS + ES compared to CS and controls (cholic acid [CA] 1.4 ng/mg vs. 0.26 ng/mg, p = 0.02 vs. 0.23 ng/mg, p = 0.004, chenodeoxycholic acid [CDCA] 1.92 ng/mg vs. 0.39 ng/mg, p = 0.02 vs. 0.23 ng/mg, p = 0.01, respectively). Fecal cholesterol excretion was similar in all three groups. Baseline serum lipid profile and subsequent changes following CS + ES were correlated. In patients with baseline hypercholesterolemia (total cholesterol (TC) > 200 mg/dl), TC levels decreased by 28.5 mg/dl, and LDL levels decreased by 21.5 mg/dl. The effect was more pronounced in those with TC > 200 mg/dl, despite of statin intake. In patients with hypertriglyceridemia [triglycerides (TG) > 200 mg/dl], TG decreased by 67.8 mg/dl following ES + CS. Among patients without dyslipidemia or dyslipidemia with adequate response to statins, the effect of ES + CS on lipid profile was minor.

CONCLUSIONS

Fecal bile acid loss increases following CS + ES. The effect on blood lipid profile depends on baseline TC and TG levels. Lipid profile is improved in dyslipidemic patients, while the impact of CS + ES is minimal on the normolipemic population.

Sexual Dimorphism in Drug Metabolism and Pharmacokinetics

Background:

Sex and gender-based differences are observed well beyond the sex organs and affect several physiological and biochemical processes involved in the metabolism of drug molecules. It is essential to understand not only the sex and gender-based differences in the metabolism of the drug but also the molecular mechanisms involved in the regulation of drug metabolism for avoiding sex-related adverse effects of drugs in the human.

Method:

The articles on the sex and gender-based differences in the metabolism of drug molecules were retrieved from the Pub Med database. The articles were classified into the metabolism of the drug molecule, gene expression regulation of drug-metabolizing enzymes, the effect of sex hormones on the metabolism of drug, expression of drugmetabolizing enzymes, etc.

Result:

Several drug molecules are known, which are metabolized differently in males and females. These differences in metabolism may be due to the genomic and non-genomic action of sex hormones. Several other drug molecules still require further evaluation at the molecular level regarding the sex and gender-based differences in their metabolism. Attention is also required at the effect of signaling cascades associated with the metabolism of drug molecules.

Conclusion:

Sex and gender-based differences in the metabolism of drugs exist at various levels and it may be due to the genomic and non-genomic action of sex hormones. Detailed understanding of the effect of sex and related condition on the metabolism of drug molecules will help clinicians to determine the effective therapeutic doses of drugs dependingon the condition of patient and disease.

Atorvastatin Induced Adverse Drug Reactions among South Indian Tamils

INTRODUCTION

Atorvastatin is the most widely used statin world-over. Although atorvastatin is beneficial in reducing cardiovascular morbidity and mortality, they are associated with Adverse Drug Reactions (ADRs) which are under-recognized as well as under-reported. There is no data on safety of atorvastatin in ethnic populations like South Indian Tamils and hence the need for this study.

AIM

To report the Adverse Events (AEs) associated with atorvastatin use, their causality and severity in dyslipidemic south Indian Tamils.

MATERIALS AND METHODS

This cross-sectional study was carried out on 304 dyslipidemic Tamils. Those on any lipid lowering therapy within one month before study enrolment, those with contraindications to statin therapy, hypothyroid patients, those with LDL cholesterol >250 mg/dL or serum triglycerides >400 mg/dL and patients who were on drugs which modulate Cytochrome P 450 3A4/5 (CYP3A4/5) activity were excluded from the study. Causality assessment for atorvastatin induced AEs were done using Naranjo adverse drug reaction probability scale criteria and severity assessment was done using Hartwig scale. AEs which were causally related to atorvastatin use were reported as ADRs.

RESULTS

One hundred and eighty three AEs were noted among 145 (47.7%) patients, during the course of first 45 days of atorvastatin therapy. AEs were probably due to atorvastatin in 11% of the patients and possibly due to atorvastatin in 89%. Most common ADRs were myalgia (41%), followed by nervous system ADRs (35.5%) and gastrointestinal ADRs (14%).

CONCLUSION

Myalgia was the most common cause for atorvastatin discontinuation which might place these individuals at an increased risk of cardiovascular morbidity and mortality. Measures to identify and address atorvastatin induced myalgia should be given priority.

ESR1 polymorphisms and statin therapy: a sex-specific approach

Lipid-lowering therapy has shown a high degree of variability in clinical response and there is evidence that the variability in drug response between individuals is due to genetic factors. Thirteen single nucleotide polymorphisms (SNPs) within the ESR1 gene were evaluated with basal lipid and lipoprotein levels, as well as response to lipid-lowering therapy, in 495 hypercholesterolemic individuals of European descent receiving simvastatin or atorvastatin. Significant associations were detected between rs4870061 (P=0.040, corrected P-value (PC)=0.440), rs1801132 (P=0.002, PC=0.022) and the SNP rs3020314 (P=0.013, PC=0.143) with triglyceride (TG) baseline levels. The rs4870061 was also associated with high-density lipoprotein cholesterol (HDL-C) baseline levels (P=0.045, PC=0.495). Regarding statin efficacy, rs2234693 C/C was associated with greater HDL-C increase (P=0.037; PC=0.407) and rs3798577 T allele was associated with greater total cholesterol (TC) reduction (P=0.019; PC=0.209) and greater TG reduction (P=0.026; PC=0.286). These associations suggest that ESR1 polymorphisms are in part responsible for the TC, HDL-C and TG variation levels and this effect may be sex-specific.

Effects of simvastatin and atorvastatin on biochemical and hematological markers in patients with risk of cardiovascular diseases

OBJECTIVE

This study aimed to investigate the effects of simvastatin (SVS) and atorvastatin (AVS) on the biochemical and hematological markers in patients with risk of cardiovascular diseases.

METHODS

One hundred and fifty outpatients were enrolled from the Department of Cardiology. Patients were treated with AVS or SVS. The lipids and hematological parameters were measured at baseline and after 4-week treatment, and the risk factors of cardiovascular diseases were recorded.

RESULTS

After 4-week treatment, the lipids significantly changed. However, for hematological parameters, only mean platelet volume (MPV) significantly decreased after statins treatment (SVS: t = 68.748, P = 0.000; AVS: t = 39.472, P = 0.000), and the extent of decline was similar between SVS group and AVS group (t = 1.063, P = 0.289). There were no correlations between MPV and lipids. SVS and AVS had comparable effects on the lipid parameters after 4-week treatment, and there were no significant correlations of ΔMPV with the Δtotal cholesterol, Δhigh density lipoprotein-cholesterol, Δlow density lipoprotein-cholesterol, Δtriglyceride, Δapolipoproteint A1, Δapolipoproteint B and Δlipoproteint (a) after treatments (all P > 0.05).

CONCLUSION

After statins treatment, the lipids significantly change; only MPV significantly decreases among hematological parameters, but it has no relationship with lipids reduction. The synthetic atorvastatin has similar effects to native simvastatin in the management of patients with risk for cardiovascular diseases.