Effects of obesity on pharmacokinetics implications for drug therapy

Anti-infectives in Pediatric Patients with Cystic Fibrosis: A Comprehensive Review of Population Pharmacokinetic Analyses

Pulmonary complications are the leading cause of morbidity and mortality in pediatric patients with cystic fibrosis. Altered pharmacokinetic parameters in this population, as well as high inter- and intra-individual variability, complicate the optimization of anti-infective treatments. In this review, we aim to summarize and describe all anti-infective population pharmacokinetic (popPK) models applied to pediatric populations with cystic fibrosis. Our objectives were to identify the most-reported structural models and retained covariates and to compare the dosing regimens used in clinical routine with those recommended in literature and guidelines. A literature search was done through the PubMed database from inception to August 2024. Studies were retained only if they complied with the inclusion and exclusion criteria. The review included 21 popPK models covering the pharmacokinetic profiles of eight different molecules. Among these, five are recommended antibiotics for treating pulmonary infections in patients with cystic fibrosis. All models incorporated body composition and/or renal function measures as covariates in their pharmacokinetic parameter equations. Standard dosing regimens in the studies were consistent with guidelines and literature recommendations. This is the first review summarizing and describing all anti-infective popPK models in pediatric patients with cystic fibrosis. Improved estimation of pharmacokinetic parameters and a clearer understanding of variability sources will enhance the optimization of antibiotic treatment in clinical practice. Finally, the impact of new targeted therapies on the management of this population will have to be closely monitored in the years ahead.

Treatment options for heart failure in individuals with overweight or obesity: a review

Obesity and heart failure are interlaced global epidemics, each contributing to significant morbidity and mortality. Obesity is not only a risk-factor for heart failure, but also complicates its management, by distinctive pathophysiological mechanisms and cumulative comorbidities, requiring tailored treatment plan. To present current treatment options for heart failure in individuals with overweight/obesity, emphasizing available pharmacological therapies, non-pharmacological strategies, and the management of related comorbidities. We conducted a comprehensive literature review regarding the results of heart failure treatments in individuals with overweight/obesity, including cornerstone interventions as well as emerging therapeutic options. Specific drug classes, including angiotensin receptor-neprilysin inhibitors, mineralocorticoid receptor antagonists, and sodium-glucose cotransporter-2 inhibitors, have demonstrated consistent efficacy in heart failure irrespective of body mass index, while diuretics remain a key for fluid management. Glucagon-like peptide-1 receptor agonists have shown promising results in improving relevant outcomes and warrant further research. Non-pharmacological approaches, including weight-loss strategies and lifestyle modifications, have shown to improve symptoms, exercise tolerance and quality of life. Managing heart failure in individuals with overweight/obesity requires a multidisciplinary, individualized approach integrating pharmacological and non-pharmacological options. Emerging therapies and preventive strategies arise to address the unique challenges in this population and provide improved outcomes.

Regional anesthesia in obese patients: Challenges, considerations, and solutions

The increasing global prevalence of obesity has significant implications for anesthesiologists, particularly in the context of regional anesthesia. Anesthesiologists face numerous challenges during anesthesia in obese patients, including compromised respiratory function, altered pharmacokinetics of local anesthetics, and difficulties in identifying anatomical landmarks. Obesity often leads to reduced respiratory reserve, increased risk of hypoventilation, and conditions such as obstructive sleep apnea syndrome and obesity hypoventilation syndrome, which increase the likelihood of postoperative complications. Additionally, altered body composition in obese patients affects the distribution of local anesthetics, requiring adjustments in dosing based on lean body weight rather than total body weight. Furthermore, excess adipose tissue complicates the identification of anatomical landmarks and the use of ultrasound for regional block procedures, as the increased tissue depth and reduced image resolution hinder needle placement. Proper positioning, the use of low-frequency transducers, and harmonic imaging techniques are essential for optimizing ultrasound guidance. Additionally, the use of longer needles and the application of trigonometric calculations based on ultrasound scans can help determine the appropriate needle length. To overcome these challenges, anesthesiologists should adopt strategies that involve adjusting drug dosages, utilizing specialized equipment, and continuously monitoring patients for potential complications. A holistic approach involving knowledge of these technical and pathological challenges, as well as adapting techniques and equipment, is crucial for ensuring the safety and effectiveness of regional anesthesia in obese patients.

Waist circumference and body surface area and the risk of developing new-onset atrial fibrillation: A systematic review and meta-analysis of observational studies

BACKGROUND

Atrial fibrillation (AF) is a prevalent cardiac arrhythmia with significant health consequences. Identifying modifiable risk factors, such as obesity, is crucial. While body mass index (BMI) is linked to increased AF risk, the association between new-onset AF (NOAF) and other anthropometric measures like waist circumference (WC) and body surface area (BSA) warrants further investigation.

OBJECTIVES

This systematic review and meta-analysis aimed to compare mean WC and BSA between individuals who developed NOAF and those who did not.

METHODS

We conducted a comprehensive search up to February 2024 for studies comparing mean WC and BSA in groups with and without incident NOAF. Participants had no prior AF history. We used a random-effects model to calculate standardized mean differences (SMDs) and 95 % confidence intervals (CIs). Subgroup analyses explored NOAF occurrence following coronary artery bypass graft (CABG) surgery, in the absence of any preceding procedure, and after other cardiac procedures.

RESULTS

Our analysis of 34 studies revealed that adults with NOAF had significantly higher WC (SMD = 0.20, 95 % CI 0.01; 0.39) and BSA (SMD = 0.06, 95 % CI 0.01; 0.11) compared to those without NOAF. Subgroup analysis showed a more pronounced association in individuals developing NOAF after CABG (SMD = 0.33, 95 % CI 0.17; 0.48) and in those without any prior procedure before NOAF diagnosis (SMD = 0.23, 95 % CI 0.08; 0.38) versus those without NOAF.

CONCLUSION

Higher WC and BSA appear to be significantly associated with an increased risk of NOAF, with the relations being more pronounced in specific subgroups.

Therapeutic Enoxaparin Dosing in Obesity

OBJECTIVE

This review aims to systematically summarize the available data on efficacy and safety of therapeutic enoxaparin in obese patients and to identify gaps to guide future research.

DATA SOURCES

Medline and Embase were systematically searched for eligible studies (last searched December 20, 2023). Studies were included if they reported on therapeutic dosing regimens, adverse bleeding, thrombotic outcomes, or antifactor Xa (AFXa) monitoring in obese adult patients.

STUDY SELECTION AND DATA EXTRACTION

The systematic review management tool Covidence was used to manage the study selection and data extraction process. The reference list from eligible studies was screened to determine any additional eligible studies.

DATA SYNTHESIS

Sixteen studies were included in the analysis. Studies used a variety of doses, indications, and study designs making comparison difficult. Twelve studies reported the incidence of thrombotic events (median = 1.3% [interquartile range [IQR] = 0.3%-2.3%]) and all studies reported the incidence of bleeding events (median = 5.7% [IQR = 2.4%-14.5%]). Two of the 8 studies analyzing the influence of weight/body mass index (BMI) or dose per kg on AFXa levels reported statistically significant results. One study concluded that BMI did not affect achievement of target AFXa levels. However, the second study found that dosing using actual body weight was an independent predictor of supratherapeutic AFXa levels in the obese population.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This is the first comprehensive review with a focus on therapeutic dosing of enoxaparin in obesity and has been conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement. Seven of the included studies were published since 2018 indicating that new evidence on this topic is emerging.

CONCLUSION

There was inadequate evidence to support an optimal dosing strategy in obese patients due to the heterogeneity of the studies. The AFXa monitoring may be appropriate to guide dosing in this population. Further research is required to determine a suitable dosing regimen.

Anesthetic Considerations in Athletes: A Review

Athletes present a unique challenge for anesthesiologists because of their specific physiology and the demands of their sport. Anesthesia for athletes requires careful consideration of factors such as muscle mass, hydration status, and the potential for drug interactions with performance-enhancing substances. Additionally, the use of specific anesthetic agents, such as inhalational and intravenous anesthetics, requires adjustments to the dosing regimen to ensure adequate anesthesia. Sports anesthesia is a subspecialty that encompasses not only expert knowledge regarding regional and general anesthesia and pain management but also the pathophysiology unique to athletes and psychological concerns associated with professional sports and complete knowledge about World Anti-Doping Agency guidelines as well as substance abuse. Moreover, the pressure of being scrutinized by a broad circle of concerned persons, including family members, team members, coaches, club owners, media, and fans, makes this an area of excellence and expertise. This review highlights how an athlete's physiological changes can alter anesthetic drug effects. Considering the importance of vigilant preoperative assessment, selecting the proper anesthesia plan, and perioperative strategies for better recovery and performance outcomes.

Efficacy of GLP-1 Receptor Agonists on Weight Loss, BMI, and Waist Circumference for Patients With Obesity or Overweight: A Systematic Review, Meta-analysis, and Meta-regression of 47 Randomized Controlled Trials

OBJECTIVE

To provide an updated synthesis on effects of glucagon-like peptide 1 receptor agonists (GLP-1 RAs) on weight, BMI, and waist circumference incorporating newer randomized controlled trials (RCTs), particularly in individuals with overweight or obesity.

RESEARCH DESIGN AND METHODS

We systematically searched PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) for RCTs published from inception to 4 October 2024. The search was limited to RCTs evaluating the use of GLP-1 RAs for mean differences from baseline in weight, BMI, and waist circumference in adults with obesity or overweight with or without diabetes. Two independent reviewers performed the literature search and data extraction, resolving disagreements via consensus or third-reviewer consultation.

RESULTS

Forty-seven RCTs were included, with a combined cohort of 23,244 patients. GLP-1 RAs demonstrated a mean weight reduction of -4.57 kg (95% CI -5.35 to -3.78), mean BMI reduction of -2.07 kg/m2 (95% CI -2.53 to -1.62), and mean waist circumference reduction of -4.55 cm (95% CI -5.72 to -3.38) compared with placebo. This effect was consistent across diabetes status, GLP-1 RA used, and route of administration. The greatest treatment benefit appeared to favor patients who were younger, female, without diabetes, with higher baseline weight and BMI but lower baseline HbA1c, and treated over a longer duration. Limitations include substantial statistical heterogeneity, in part due to broad inclusion criteria. However, this heterogeneity may improve generalizability by reflecting a wide range of study designs and patient populations.

CONCLUSIONS

GLP-1 RAs demonstrated significant weight, BMI, and waist circumference reduction benefits in this meta-analysis.

Safety, Tolerability, and Pharmacokinetics of a Novel Anti-obesity Agent, S-309309, in Healthy Adults with or Without Obesity

BACKGROUND

Anti-obesity medications are recommended for patients who do not achieve and maintain weight loss despite lifestyle interventions. S-309309 is a novel oral inhibitor of monoacylglycerol O-acyltransferase 2 being developed as a treatment for obesity.

OBJECTIVE

The objective of the study was to investigate the safety, clinical pharmacology, pharmacokinetics and pharmacodynamic biomarker of S-309309.

METHODS

A phase I, single-center, two-part, randomized, double-blind, placebo-controlled study of S-309309 following oral administration of a single-ascending dose (part 1) and a multiple dose (part 2) in healthy adults with or without obesity was conducted. We also assessed the effect of food on the pharmacokinetics of S-309309 and the effect of S-309309 on electrocardiogram parameters, the pharmacokinetics of midazolam (a cytochrome P450 3A substrate), and the pharmacodynamic biomarker of monoacylglycerol O-acyltransferase 2 inhibition.

RESULTS

In part 1 (N = 50), a single-ascending dose of S-309309 in healthy adults demonstrated dose proportionality and comparable exposure of S-309309 between the fasted and fed states. In part 2 (N = 24), no clinically meaningful difference was observed in the pharmacokinetics of multiple doses between healthy adults with or without obesity. S-309309 did not affect the pharmacokinetics of the cytochrome P450 3A substrate. The pharmacodynamic biomarker of monoacylglycerol O-acyltransferase 2 inhibition, dicarboxylic acid (18:1), was significantly increased after S-309309 administration in healthy adults with or without obesity. Overall, S-309309 demonstrated acceptable safety and tolerability without any serious adverse events or discontinuations because of adverse events, and did not have a clinically relevant effect on the heart rate or cardiac conduction. An effect on the placebo-corrected change-from-baseline corrected QT interval, corrected for heart rate using the Fridericia method, exceeding 10 ms can be excluded.

CONCLUSIONS

S-309309 was well tolerated as single-dose (up to 300 mg) and multiple-dose (50 mg once daily for 14 days) oral administration. The pharmacokinetic characteristics remained unaffected by obesity and food intake. S-309309 did not affect the pharmacokinetics of the cytochrome P450 3A substrate. Overall, S-309309 had an acceptable safety profile and favorable pharmacokinetic and pharmacodynamic characteristics.

CLINICAL TRIAL REGISTRATION

NCT05247970, date of registration: 8 February, 2022.

Influence of Obesity on the Efficacy and Toxicity of Patients Undergoing Autologous Hematopoietic Cell Transplantation for Lymphoma

Hematopoietic cell transplantation requires higher doses of chemotherapy, and practices of adjusting the weight because of concerns of organ toxicity are common. This retrospective analysis of 239 adult recipients of autologous hematopoietic cell transplantation for lymphoma assessed the effect of obesity on transplantation outcomes.

BACKGROUND

Prior data evaluating the impact of obesity in autologous hematopoietic cell transplantation (AHCT) for lymphomas have provided differing results when assessing overall (OS) and progression-free survival (PFS). Impact on survival outcomes have been described, but direct comparison of discrete toxicities is lacking.

PATIENTS AND METHODS

We retrospectively compared outcomes with patients divided between 3 groups: nonobese patients (n = 129), obese patients dosed on adjusted body weight (AdjBW) (n = 32), and obese patients dosed on total body weight (TBW) (n = 78).

RESULTS

In multivariate analysis of OS with the nonobese group as the comparator, outcomes trended worse in obese patients dosed on AdjBW (HR 1.22, 95% CI 0.52-2.85) but were improved in obese patients dosed on TBW (HR 0.19, 95% CI 0.04-0.85, P = .012). PFS of obese patients dosed on AdjBW vs. the nonobese group was comparable (HR 1.19, 95% CI 0.63-2.24), but improved in obese patients dosed on TBW (HR 0.45, 95% CI 0.23-0.89, P = .021). Notably, no differences were noted between groups in gastrointestinal, infectious, renal, or hepatic toxicities.

CONCLUSION

In summary, our data suggest that recipients of AHCT for lymphoma should be dosed on TBW to maximize curative outcomes with no apparent increase in toxicities.

Pharmacodynamic Modeling of Warfarin Dosing Algorithm for Cardiovascular Patients in Indonesia: A Tailored Method to Anticoagulation Therapy

Purpose

Warfarin is an anticoagulant drug widely used for treating thromboembolism-related conditions. The main challenge with this drug is the high variability in patients response, which is influenced by both clinical, non-clinical, and genetic factors, such as VKORC1, CYP2C9, and CYP4F2. Therefore, this research aimed to evaluate the impact of clinical and genetic factors on warfarin dose adjustment and to develop a dosing algorithm for patients with cardiovascular disease.

Patients and Methods

A total of 77 research subjects were selected using consecutive sampling based on the inclusion criteria of cardiac outpatients on warfarin for ≥3 months with PT-INR data, complete medical records, and willingness to participate. Exclusion criteria included vitamin K use and inability to follow up. Patients demographic data and clinical characteristics were collected from medical records. Blood samples were obtained for genetic testing of CYP4F2 rs2108622 (sequencing). Statistical analyses included both bivariate and multivariate analyses (logistic regression) with a significance level set at <0.05.

Results

Statistical analysis using the Kruskal-Wallis test showed that the CC, CT, and TT genotypes were significantly associated with warfarin dose (p = 0.02). Furthermore, the Mann-Whitney test results showed that gender did not have a significant relationship with warfarin dose (p = 0.16). The Spearman Rank correlation test showed that age (p = 0.02) and BMI (p = 0.03) had significant relationships with warfarin dose (p < 0.05). However, gender (p = 0.89) had no effect, while age (p = 0.01), BMI (p = 0.01), and genotype (p = 0.01) significantly influenced warfarin dose determination.

Conclusion

In conclusion, the combined contribution of age (8.76%), BMI (7.95%), and CYP4F2 genotype (8.29%) to warfarin dose adjustment was 25%. The linear regression model for predicting warfarin dose was determined to be y = 12.736-0.16*age + 0.55*BMI + 3.55*genotype, where 1 = CC, 2 = CT, and 3 = TT.

Risk Factors and Patterns of Drug-Drug Interactions in Two Categories of Level-3 Hospitals in Dhaka: A Cross-Sectional Study

Background and Aims

Drug-drug interactions (DDIs) are a significant health issue that may adversely affect the health and well-being of patients. This study assesses and compares potential DDI (pDDI) patterns, severity, and associated risk factors in government and private hospitals in Dhaka, Bangladesh.

Methods

A total of 188 and 206 prescriptions were collected from various government and private hospitals' outdoor departments, respectively, by capturing pictures of the prescriptions. Bivariate analyses were performed through STATA 15. MedScape drug interaction checker was applied to identify pDDIs, while their consequences were obtained from DrugBank and MedScape.

Results

Private hospitals had more pDDIs containing prescriptions than government hospitals (62.62% and 57.97%, respectively). The mean pDDIs cases were 3.29 in the private hospitals, while at government hospitals they were 3.02. Among the detected pDDIs, pharmacodynamic pDDIs were predominat, accounting for 63.32% and 66.23% of total events in government and private hospitals, respectively. Severity-wise, both types of hospitals had almost equal amounts of serious (10.34% vs. 9.18%), moderate (68.96% vs. 59.61%), and minor (20.06% vs. 21.79%) pDDIs. Polypharmacy was crucial in pDDI cases, responsible for 70.21% and 81.83% of pDDIs in government and private hospitals, respectively. Multiple comorbidities with pDDIs were more common in private hospitals (24.46% vs. 18.93%), while government hospitals displayed a higher frequency of pDDIs with one comorbidity (24.75% vs. 17.55%). Non-mention of comorbidities was correlated with both types of hospitals (p ≤ 0.01) in pDDIs cases. Furthermore, considerable amounts of pDDIs in prescription error categories were detected. Both types of hospitals had a prevalence of antihypertensive, antidiabetic, psychotic, and antiplatelet-related pDDIs.

Conclusion

The two kinds of hospitals exhibited similar pDDI patterns, while their associations were random with the risk variables. When prescribing pharmacokinetics and pharmacodynamics pDDIs, physicians should evaluate the risk-benefit ratio.

Finding individualised treatment in obese needing enoxaparin (FIT ONE): a multicentre study of therapeutic enoxaparin and the role of anti-factor Xa monitoring

Enoxaparin is dosed according to actual body weight in treatment of arterial and venous thrombosis. Due to its hydrophilic nature, it distributes according to lean body mass which may be problematic when dosing obese patients as this may increase the risk of bleeding events in this population. The aim was to evaluate current therapeutic enoxaparin dosing strategies, including Antifactor Xa (AFXa) level monitoring, in obese patients and to identify factors that contribute to treatment failure and excess anticoagulation. A retrospective cohort study was conducted reviewing patients administered therapeutic enoxaparin between May 2020 and April 2021. Data were collected on patient characteristics, enoxaparin therapy, AFXa monitoring, and outcomes. Regression models were constructed to assess variables of interest to estimate any association with AFXa levels. In total 762 patients were included in the analysis. The mean initial weight-based dose was 0.95 mg/kg twice daily (SD: ± 0.12, IQR 0.92-1.01) and 1.04 mg/kg once daily (SD: ± 0.26, IQR 0.93-1.12) and 14.4% of patients had AFXa monitoring. Treatment failure was experienced by 2.2%, 5% experienced bleeding. There was no association between the mean actual milligram per kilogram weight-based twice daily doses and subtherapeutic, therapeutic and supratherapeutic AFXa levels (P = 0.135). Obesity was not included in the final regression models due to lack of significance. At a mean therapeutic enoxaparin dose of 0.95 mg/kg twice daily and 1.04 mg/kg once daily no excess in treatment failure or bleeding events were observed in obese patients compared to the product information. Obesity was not an independent variable that affected the achievement of target AFXa levels.

Combined carbapenem resulted in a 4.48-fold increase in valproic acid clearance: a population pharmacokinetic model in Chinese children and adults with epilepsy or after neurosurgery

Our study aims to explore the pharmacokinetics of valproic acid (VPA) in Chinese patients with epilepsy or after neurosurgery and establish a robust population pharmacokinetics (PPK) model. The PPK model was developed using nonlinear mixed-effects modeling, incorporating a total of 615 VPA plasma concentration data points from 443 Chinese epilepsy or after neurosurgery patients. A one-compartment model with an additive residual model was established. Forward addition and backward elimination strategies were used to assess the impact of covariates on the model parameters. Goodness-of-fit plots, bootstrap, visual predict check and normalized prediction distribution errors were used for model validation. In the final model, the apparent clearance (CL) was estimated using the following formula: CL  L / h = 0.430 × BW / 60 0.787 × Cr / 50.3 - 0.253 × ALB / 39 - 0.873 × e gender × e CBP × e IND 2   × e η CL (gender = 0.121 when is female, otherwise = 0; CBP = 1.50 when combined with carbapenems, otherwise = 0; IND2 = 0.15 when combined with oxcarbazepine, carbamazepine, phenobarbital, or phenytoin, otherwise = 0). The volume of distribution (Vd) was estimated using the formula: Vd  L = 8.66 × BW / 60 0.751 . Comedication with carbapenems could increase VPA clearance by 4.48 times, and comedication with oxcarbazepine could enhance VPA clearance by 116%. Besides, creatinine and albumin could affect VPA clearance. Goodness-of-fit plots, bootstrap, visual predict check and normalized prediction distribution showed acceptable data fit, stability, and predictability of the model. In our study, a PPK model was utilized to attain a more comprehensive insight into these variables, improving the accuracy and individualization of VPA therapy in Chinese patients with epilepsy or after neurosurgery.

Effect of Helicobacter pylori on sleeve gastrectomy and gastric microbiome differences in patients with obesity and diabetes

BACKGROUND

Obesity and diabetes mellitus (DM) have become public health concerns worldwide. Both conditions have severe consequences and are associated with significant medical costs and productivity loss. Additionally, Helicobacter pylori infection may be a risk factor for the development of these conditions. However, whether eradicating H. pylori infection directly causes weight loss or improves insulin sensitivity is unknown.

METHODS

In this study, we confirmed the effect of sleeve gastrectomy according to the state of the gastric microbiota in 40 patients with obesity, DM, and H. pylori infection. Patients with obesity were divided into four groups: non-DM without H. pylori infection (ND), non-DM with H. pylori infection (ND-HP), DM, and DM with H. pylori infection (DM-HP) using 16S V3-V4 sequencing.

RESULTS

In the DM group, ALT, hemoglobin, HbA1c, blood glucose, and HSI significantly decreased, whereas high-density lipoprotein significantly increased. However, in the H. pylori-positive group, no significant difference was observed. The diversity of gastric microbiota decreased in the order of the ND > DM > ND-HP > DM-HP groups. We also conducted a correlation analysis between the preoperative microbes and clinical data. In the ND-HP group, most of the top 20 gastric microbiota were negatively correlated with glucose metabolism. However, H. pylori infection was positively correlated with pre-insulin levels.

CONCLUSION

Therefore, these findings indicate that patients with obesity and diabetes clearly benefit from surgery, but H. pylori infection may also affect clinical improvement.

Medication Dosing for Children With Overweight and Obesity

Approximately 14.7 million US children aged 2 to 19 years are obese. This creates significant challenges to dosing medications that are primarily weight based (mg/kg) and in predicting pharmacokinetics parameters in pediatric patients. Obese individuals generally have a larger volume of distribution (Vd) for lipophilic medications. Conversely, the Vd of hydrophilic medications may be increased or decreased owing to increased lean body mass, blood volume, and decreased percentage of total body water. They may also experience decreased hepatic clearance secondary to fatty infiltrates of the liver. Hence, obesity may affect loading dose, dosage interval, plasma half-life, and time to reach steady-state concentration for various medications. Weight-based dosing is also a cause for potential medication errors. This position statement of the Pediatric Pharmacy Association recommends that weight-based dosing should be used in patients ages <18 years who weigh <40 kg; weight-based dosing should be used in patients ≥40 kg, unless the recommended adult dose for the specific indication is exceeded; clinicians should use pharmacokinetic analysis for adjusting medications in children diagnosed with overweight and obesity; and research efforts continue to evaluate dosing of medications in children diagnosed with overweight and obesity.

Screening and Perioperative Management of Obesity Hypoventilation Syndrome

Obesity hypoventilation syndrome (OHS) can often be underdiagnosed or misdiagnosed and has been shown to pose significant risks in perioperative situations. Patients with OHS have a higher prevalence of baseline morbid conditions like hypertension, congestive heart failure (CHF), diabetes mellitus, atrial fibrillation, and pulmonary hypertension (PH), which contribute to adverse postoperative outcomes. The potential challenges include difficult intubation and loss of airway, postoperative respiratory failure, worsening heart failure, pulmonary hypertensive crisis, and opioid-induced respiratory depression (OIRD). It is, therefore, important to screen all obese patients for obstructive sleep apnea (OSA) and OHS before elective surgical procedures. The aim of this review is to discuss the preoperative screening and evaluation and safe anesthetic and up-to-date ventilatory management of this complex group of patients. This review also intends to increase the awareness of OHS in the adult population among hospitalists, surgeons, and cardiologists who may find themselves taking care of these patients in complex multidisciplinary settings.

Physiologically based pharmacokinetic modeling in obesity: applications and challenges

INTRODUCTION

Rising global obesity rates pose a threat to people's health. Obesity causes a series of pathophysiologic changes, making the response of patients with obesity to drugs different from that of nonobese, thus affecting the treatment efficacy and even leading to adverse events. Therefore, understanding obesity's effects on pharmacokinetics is essential for the rational use of drugs in patients with obesity.

AREAS COVERED

Articles related to physiologically based pharmacokinetic (PBPK) modeling in patients with obesity from inception to October 2023 were searched in PubMed, Embase, Web of Science and the Cochrane Library. This review outlines PBPK modeling applications in exploring factors influencing obesity's effects on pharmacokinetics, guiding clinical drug development and evaluating and optimizing clinical use of drugs in patients with obesity.

EXPERT OPINION

Obesity-induced pathophysiologic alterations impact drug pharmacokinetics and drug-drug interactions (DDIs), altering drug exposure. However, there is a lack of universal body size indices or quantitative pharmacology models to predict the optimal for the patients with obesity. Therefore, dosage regimens for patients with obesity must consider individual physiological and biochemical information, and clinically individualize therapeutic drug monitoring for highly variable drugs to ensure effective drug dosing and avoid adverse effects.

Effect of Obesity on the Use of Antiarrhythmics in Adults With Atrial Fibrillation: A Narrative Review

BACKGROUND

Atrial fibrillation (AF) and obesity coexist in approximately 37.6 million and 650 million people globally, respectively. The anatomical and physiological changes in individuals with obesity may influence the pharmacokinetic properties of drugs.

AIM

This review aimed to describe the evidence of the effect of obesity on the pharmacokinetics of antiarrhythmics in people with AF.

METHODS

Three databases were searched from inception to June 2023. Original studies that addressed the use of antiarrhythmics in adults with AF and concomitant obesity were included.

RESULTS

A total of 4549 de-duplicated articles were screened, and 114 articles underwent full-text review. Ten studies were included in this narrative synthesis: seven cohort studies, two pharmacokinetic studies, and a single case report. Samples ranged from 1 to 371 participants, predominately males (41%-85%), aged 59-75 years, with a body mass index (BMI) of 23-66 kg/m2. The two most frequently investigated antiarrhythmics were amiodarone and dofetilide. Other drugs investigated included diltiazem, flecainide, disopyramide, propafenone, dronedarone, sotalol, vernakalant, and ibutilide. Findings indicate that obesity may affect the pharmacokinetics of amiodarone and sodium channel blockers (e.g., flecainide, disopyramide, and propafenone). Factors such as drug lipophilicity may also influence the pharmacokinetics of the drug and the need for dose modification.

DISCUSSION

Antiarrhythmics are not uniformly affected by obesity. This observation is based on heterogeneous studies of participants with an average BMI and poorly controlled confounding factors such as multimorbidity, concomitant medications, varying routes of administration, and assessment of obesity. Controlled trials with stratification at the time of recruitment for obesity are necessary to determine the significance of these findings.

Competing Benefits and Competing Hazards: The Benefit to Harm Balance in Individual Patients in Rational Therapeutics

For any therapeutic intervention in an individual, there is a balance between the potential benefits and the possible harms. The extent to which the benefits are desirable in a given condition depends on the efficacy of the intervention, the chance of obtaining it and the seriousness and intensity of the condition. The extent to which the harms are undesirable depends on the nature of the hazard that can lead to harm, the chance that the harm will occur and its seriousness and intensity. Rational therapeutic decisions require clinicians to consider competing courses of action, with potential benefits of different desirability and potential harms of different undesirability. They also have a duty to explain to the patient, for the contemplated interventions, both the possible benefits and the potential harms that the patient may consider significant. In an individual patient, it is necessary to consider (a) the probabilities of benefit from both intervention and non-intervention and (b) the probabilities of harm from both intervention and non-intervention. However, there are several potential problems. Here, we consider how failure to distinguish maximum benefits from probable benefits, or hazards (potential harms) from probable harms, and failure to consider all the competing probabilities may lead to imperfect therapeutic decisions. We also briefly discuss methods to assess the benefit to harm balance.

Optimization and validation of a fat-on-a-chip model for non-invasive therapeutic drug discovery

Obesity is a significant public health concern that is closely associated with various comorbidities such as heart disease, stroke, type II diabetes (T2D), and certain cancers. Due to the central role of adipose tissue in many disease etiologies and the pervasive nature in the body, engineered adipose tissue models are essential for drug discovery and studying disease progression. This study validates a fat-on-a-chip (FOAC) model derived from primary mature adipocytes. Our FOAC model uses a Micronit perfusion device and introduces a novel approach for collecting continuous data by using two non-invasive readout techniques, resazurin and glucose uptake. The Micronit platform proved to be a reproducible model that can effectively maintain adipocyte viability, metabolic activity, and basic functionality, and is capable of mimicking physiologically relevant responses such as adipocyte hypertrophy and insulin-mediated glucose uptake. Importantly, we demonstrate that adipocyte size is highly dependent on extracellular matrix properties, as adipocytes derived from different patients with variable starting lipid areas equilibrate to the same size in the hyaluronic acid hydrogel. This model can be used to study T2D and monitor adipocyte responses to insulin for longitudinally tracking therapeutic efficacy of novel drugs or drug combinations.

Association between institutionalization by 4 months post-discharge walking capacity and lean body mass in elderly hip fracture patients: Evidence from a Swedish Registry Based Study

Background and purpose

Losing independence is a main concern for hip fracture patients, and particularly not being able to return home. Given the large impact on quality of life by loss of independence and the high risk for institutionalization after hip fracture, it is of importance to identify modifiable risk factors for such negative outcomes. This study aimed to investigate the association between two such factors, that is, lean body mass and 4 months post-discharge walking capacity, and the risk of institutionalization in previously independent living older people who suffer a hip fracture.

Patients and methods

A retrospective cohort study was conducted using Swedish national-based population registers. Patients ⩾60 years with a hip fracture during 2008-2017 were included from the Swedish National Registry for Hip Fractures. Risk of institutionalization over the 1-year period following a hip fracture was analyzed using logistic regression analyses adjusted for potential predictors and characteristics.

Results

In total, 11,265 patients were included. Over the first year, 8% (95% CI: 8-9) of the patients with a hip fracture had lost independence, increasing to 15% (95% CI: 14-16) after 5 years. Poor recovery of post-discharge walking ability was associated with a higher odds ratio of losing independence compared with good recovery (OR 12.0; 95% CI: 7.8-18.4; p < 0.001). Having higher estimated lean body mass than 45 kg at index was associated with lower odds of losing independence.

Conclusion

Maintaining lean body mass and mobility after a hip fracture is likely important from an individual as well as public health perspective.

Impact of Body Mass Index in the Cardioverter Efficacy of Amiodarone in Persistent Atrial Fibrillation

BACKGROUND

Amiodarone is an anti-arrhythmic drug that has extensive tissue distribution and substantial storage in the fat tissue. Different studies have described some implications of body fat composition in its pharmacokinetics and pharmacodynamics. However, no clinical studies have described its implications for clinical efficacy.

METHODS

We studied 878 patients with persistent atrial fibrillation (AF) treated with a regimen of amiodarone and referred to electrical cardioversion (ECV), included prospectively in two Spanish registries. We analyzed the influence of body mass index (BMI), as well as overweight and obesity, in the efficacy of amiodarone for achieving pharmacologic cardioversion to sinus rhythm (SR) before ECV.

RESULTS

A total of 185 patients (21.1%) reverted to SR before ECV. Patients who reverted to SR had a lower BMI than those who did not revert (27.45 ± 4.36 kg/m2 vs. 29.11 ± 4.09 kg/m2; p < 0.001). We observed a progressively lower probability of reverting to SR in overweight and obese patients (normal weight 28.3%, overweight 21.3%, obesity 13.1%; p < 0.001). In the logistic regression, BMI (kg/m2) adjusted for other related variables remained as the main factor inversely related to reversion to SR (OR = 0.904 × kg/m2); CI 75% 0.864-0.946).

CONCLUSIONS

We observed a negative relationship between an increased BMI and the efficacy of amiodarone for reversion to SR, suggesting a negative clinical impact of excess body fat in its efficacy.

Reporting on patient's body mass index (BMI) in recent clinical trials for patients with breast cancer: a systematic review

BACKGROUND

The proportion of patients with breast cancer and obesity is increasing. While the therapeutic landscape of breast cancer has been expanding, we lack knowledge about the potential differential efficacy of most drugs according to the body mass index (BMI). Here, we conducted a systematic review on recent clinical drug trials to document the dosing regimen of recent drugs, the reporting of BMI and the possible exclusion of patients according to BMI, other adiposity measurements and/or diabetes (leading comorbidity of obesity). We further explored whether treatment efficacy was evaluated according to BMI.

METHODS

A search of Pubmed and ClinicalTrials.gov was performed to identify phase I-IV trials investigating novel systemic breast cancer treatments. Dosing regimens and exclusion based on BMI, adiposity measurements or diabetes, documentation of BMI and subgroup analyses according to BMI were assessed.

RESULTS

495 trials evaluating 26 different drugs were included. Most of the drugs (21/26, 81%) were given in a fixed dose independent of patient weight. BMI was an exclusion criterion in 3 out of 495 trials. Patients with diabetes, the leading comorbidity of obesity, were excluded in 67/495 trials (13.5%). Distribution of patients according to BMI was mentioned in 8% of the manuscripts, subgroup analysis was performed in 2 trials. No other measures of adiposity/body composition were mentioned in any of the trials. Retrospective analyses on the impact of BMI were performed in 6 trials.

CONCLUSIONS

Patient adiposity is hardly considered as most novel drug treatments are given in a fixed dose. BMI is generally not reported in recent trials and few secondary analyses are performed. Given the prevalence of patients with obesity and the impact obesity can have on pharmacokinetics and cancer biology, more attention should be given by investigators and study sponsors to reporting patient's BMI and evaluating its impact on treatment efficacy and toxicity.

[An online tool to personalize the drug-doses for obese adults]

BACKGROUND

Between 1975 and 2014, the number of people suffering from obesity tripled, reaching 17% of the adult population in France and more than 35% in the United States. Obesity is defined by a Body Mass Index (BMI)>30kg/m2 and characterized by a significant accumulation of adipose tissue responsible for the increase in weight. This accumulation leads to physiological changes capable of modifying the pharmacokinetics of drugs, which can lead to the administration of inappropriate doses. For this reason, some significant dosage adjustments are necessary for obese patients. However, data on these adaptations are not easily accessible and sometimes complex to implement in practice.

AIM

To perform a new online tool allowing to calculate and propose an adjusted dose of a drug that should be administered to an obese patient.

METHOD

(i) carrying out an extensive bibliographic research according to the PRISMA methodology; and (ii) the development of a new website site proposing an adjusted dose for obese patients.

RESULTS

Firstly, 49 reviews concerning the dose adaptation have been evaluated and, secondly, 319 articles have been selected. Among them, 204 articles have been included in the database to justify the adjusted dose of 84 drugs and administration methods including antibiotics, antifungals, anticoagulants or even cancer drugs. This database is available online through a calculator on the website named Adapt'Obese. Thus, with the sex, height and weight of an obese patient, Adapt'Obese proposes a personalized and adjusted dose of the drug to administer.

PERSPECTIVES

Other drugs will be added soon, and functional improvements are planned, with the aim of adapting the dosages in obese patients, as for patients with renal insufficiency.

Influence of Weight and Body Size on the Pharmacokinetics of Heart Failure Pharmacotherapy: A Systematic Review

OBJECTIVE

To conduct a review of studies evaluating the influence of body size and weight (WT) on the pharmacokinetics (PK) of drugs recommended for heart failure (HF) treatment.

DATA SOURCES

A systematic search of the MEDLINE (1946 to April 2023) and EMBASE (1974 to April 2023) databases was conducted for articles that focused on the impact of WT or body size on the PK of drugs of interest used in HF patients.

STUDY SELECTION AND DATA EXTRACTION

Articles written in English or French related to the aim of our study were retained for analysis.

DATA SYNTHESIS

Of 6493 articles, 20 were retained for analysis. Weight was associated with the clearance of digoxin, carvedilol, enalapril, and candesartan as well as the volume of distribution of eplerenone and bisoprolol. There was no documented direct impact of WT on the PK of furosemide, valsartan, and metoprolol, although these studies were limited or confounded by the small sample size, adjustment of PK factors by WT, or the use of the Cockroff-Gault equation for the evaluation of creatinine clearance, which includes WT.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review highlights and summarizes the available data on the importance of WT on the PK of HF treatment.

CONCLUSION

Considering the significant impact of WT on most HF drugs in this review, it may be important to further investigate it in the context of personalized therapy, particularly in patients presenting extreme WTs.

Predictors for Dexmedetomidine Requirement for Sedation under Regional Anesthesia

(1) Background: This prospective observational study aimed to investigate the predictors affecting DMT requirements for sedation during regional anesthesia. (2) Method: A total of 108 patients who received regional anesthesia with intravenous DMT administration for orthopedic upper- or lower-extremity surgery were enrolled. Following successful regional anesthesia, DMT was administered at a rate of 4 µg/kg/h until reaching loss of consciousness (LOC). The administered dose of DMT per body weight until LOC (DMTLOC; µg/kg) was evaluated. The infusion was maintained at a rate of 0.2-0.7 µg/kg/h during the surgery. At the end of surgery, the elapsed time to a BIS value of 90 (TBIS90; s) was recorded. Linear regression models were used to identify potential predictors of DMTLOC and TBIS90. (3) Results: One hundred patients were analyzed. There were negative relationships between DMTLOC and age (r = -0.297, p = 0.003) and DMTLOC and body mass index (BMI) (r = -0.425, p < 0.001), respectively. Multiple linear regression models revealed that both increasing age and BMI were significantly related to DMTLOC (r2 = 0.259, p < 0.001), but those variables showed no association with TBIS90. (4) Conclusions: The results of this study suggest that initial loading of DMT should be carefully titrated to minimize risk in elderly and obese surgical populations.

Castelino R, Inglis SC, Davidson PM, Ferguson C. Direct oral anticoagulant use in hospitalized patients with atrial fibrillation across body mass index categories: design and rationale for a retrospective cohort study

Background

Atrial fibrillation (AF) and obesity are common conditions globally; yet, there remains suboptimal pharmacological management contributing to high rates of hospitalization in patients with AF. The altered pathophysiology of both obese and underweight individuals may influence the pharmacology of medications, including those used to manage AF. This, in turn, increases the risk of adverse events and impacts patient risk for stroke and rehospitalization. Despite the well-established complications of obesity, research investigating the relationship between obesity and AF is scant.

Objectives

The primary aim of this study is to describe cardiovascular-related hospitalization in AF patients according to BMI categories. A secondary aim is to describe anticoagulant and antiarrhythmic prescribing practice patterns in patients with AF, according to the BMI category.

Design

A retrospective, exploratory descriptive observational cohort study, using routinely collected electronic medical record data from five public hospitals within a single health district, with a population dominantly that is culturally and linguistically diverse, and has a low socioeconomic status.

Methods and analysis

Data extraction will include a 24-month period (January 2017 to December 2018) with a 12-month follow-up. All adult (⩾18 years) patients at discharge diagnosed with AF, prescribed any oral anticoagulant and/or oral rate/rhythm control agent, will be eligible for inclusion.

Ethics and dissemination

Ethics approval from the health district and the University of Wollongong has been granted. Findings will seek to demonstrate associations between management strategies and patient outcomes, as well as describe patterns of acute care management from prescribers. These data will be used to inform and generate hypotheses for large-scale studies examining the impact of body weight on anticoagulation prescribing at national and global scales.

Impact of Obesity on Atrial Fibrillation Pathogenesis and Treatment Options

Atrial fibrillation (AF) is the most common cardiac arrhythmia. AF increases the risk of stroke, heart failure, dementia, and hospitalization. Obesity significantly increases AF risk, both directly and indirectly, through related conditions, like hypertension, diabetes, and heart failure. Obesity-driven structural and electrical remodeling contribute to AF via several reported mechanisms, including adiposity, inflammation, fibrosis, oxidative stress, ion channel alterations, and autonomic dysfunction. In particular, expanding epicardial adipose tissue during obesity has been suggested as a key driver of AF via paracrine signaling and direct infiltration. Weight loss has been shown to reverse these changes and reduce AF risk and recurrence after ablation. However, studies on how obesity affects pharmacologic or interventional AF treatments are limited. In this review, we discuss mechanisms by which obesity mediates AF and treatment outcomes, aiming to provide insight into obesity-drug interactions and guide personalized treatment for this patient subgroup.

Comparison of Fat-Free Mass and Ideal Body Weight Scalar for Anesthetic Induction Dose of Propofol in Patients with Morbid Obesity: A Double-Blind, Randomized Clinical Trial

Background

Obesity is a growing problem worldwide and can affect both the pharmacodynamics and pharmacokinetics of various drugs, including anesthetics, resulting in the under-or overdosing of certain drugs. There is no consensus on the ideal dosing regimen for obese populations.

Objectives

In this study, 2 weight-based dosing of propofol used for induction of anesthesia were compared in terms of the onset of action time, adequacy of anesthesia, and effects on hemodynamic indices (eg, heart rate [HR] and blood pressure).

Methods

In this randomized, double-blind clinical trial, 40 patients with morbid obesity (MO) scheduled for bariatric surgery with body mass index (BMI) > 35, age 18 - 59 years, American Society of Anesthesiologists physical status (ASA-PS) II and III were randomly divided into 2 groups, using block randomization method, to receive 2 mg/kg of propofol for induction of anesthesia based on either fat-free mass (FFM) group or ideal body weight (IBW) group. The primary outcome was the time duration to reach the bispectral index (BIS) ≤ 60. Time to the disappearance of eyelash reflex, signs of inadequate anesthesia (ie, BIS > 60, straining during intubation, or eye-opening), requirements for additional doses, and hemodynamic indices (including HR and mean arterial pressure [MAP]) were also compared.

Results

The mean time to reach BIS ≤ 60 was 134.1 s in the FFM group and 148.7 s in the IBW group. This difference was not statistically significant (P = 0.334). The time of disappearance of eyelash reflex was also not significantly different between the study groups (P = 0.814). However, 2 patients in the FFM group and 8 patients in the IBW group showed signs of inadequate anesthesia and required additional doses. This difference was statistically significant (P = 0.032). Hemodynamic variables, before and 2 min after propofol induction dose administration were comparable between the study groups (P = 0.520, P = 0.327, P = 0.847, P = 0.516 for pre-intervention MAP, post-intervention MAP, pre-intervention HR, and post-intervention HR, respectively).

Conclusions

Propofol dosing, based on FFM and IBW, for induction of anesthesia, provides comparable onset time of action and hemodynamic effects; however, in terms of the adequacy of anesthesia, the dosing based on FFM is more favorable compared to the dosing based on IBW.

Pharmacokinetic analysis of acute and dietary exposure to piperonyl butoxide in the mouse

Piperonyl butoxide (PBO) is a popular insecticide synergist present in thousands of commercial, agricultural, and household products. PBO inhibits cytochrome P450 activity, impairing the ability of insects to detoxify insecticides. PBO was recently discovered to also inhibit Sonic hedgehog signaling, a pathway required for embryonic development, and rodent studies have demonstrated the potential for in utero PBO exposure to cause structural malformations of the brain, face, and limbs, or more subtle neurodevelopmental abnormalities. The current understanding of the pharmacokinetics of PBO in mice is limited, particularly with respect to dosing paradigms associated with developmental toxicity. To establish a pharmacokinetic (PK) model for oral exposure, PBO was administered to female C57BL/6J mice acutely by oral gavage (22-1800 mg/kg) or via diet (0.09 % PBO in chow). Serum and adipose samples were collected, and PBO concentrations were determined by HPLC-MS/MS. The serum concentrations of PBO were best fit by a linear one-compartment model. PBO concentrations in visceral adipose tissue greatly exceeded those in serum. PBO concentrations in both serum and adipose tissue decreased quickly after cessation of dietary exposure. The elimination half-life of PBO in the mouse after gavage dosing was 6.5 h (90 % CI 4.7-9.5 h), and systemic oral clearance was 83.3 ± 20.5 mL/h. The bioavailability of PBO in chow was 41 % that of PBO delivered in olive oil by gavage. Establishment of this PK model provides a foundation for relating PBO concentrations that cause developmental toxicity in the rodent models to Sonic hedgehog signaling pathway inhibition.

The Importance of Assessing Drug Pharmacokinetics and Pharmacodynamics in the Obese Population During Drug Development

Obesity remains a US national health crisis and a growing concern worldwide. Concerningly, individuals who are obese are at an increased risk for comorbid diseases that include, but are not limited to, hypertension, diabetes, cardiovascular disease, and cancer. Beyond the risk for developing these conditions, obesity may also impact the pharmacological activity of the therapies being used to treat them and other disease states. The pharmacokinetics (PK), pharmacodynamics (PD), safety, and efficacy of therapies, both currently marketed and under clinical development, may be directly impacted by the physiological alterations that occur secondary to the occurrence of chronic excess body weight. The increased prevalence of this disease should not be ignored. Both private and federal institutions involved in drug research and development should consider, as appropriate, a greater inclusion of individuals who are obese in clinical trials throughout the entirety of drug development, and leverage the available PK, PD, safety, and efficacy data to make more informed dosing recommendations.

Comprehensive Review of Anesthetic Evaluation and Management in Obese Female Patients Undergoing In Vitro Fertilization

Obesity has become a global health epidemic with profound implications for various medical specialties, including reproductive medicine. This comprehensive review focuses on the anesthetic evaluation and management of obese patients undergoing in vitro fertilization (IVF) procedures. Obesity, as defined by BMI, is associated with infertility and poses unique challenges for anesthetic care. The review also addresses the timing of anesthesia concerning IVF procedures, the impact of obesity on IVF success rates, and the importance of emotional and psychological support for obese patients undergoing IVF. Challenges and future directions in the field are highlighted, focusing on ongoing research, emerging technologies, and the role of multidisciplinary teams in managing these complex cases. In conclusion, this review underscores the critical role of tailored anesthesia and perioperative care in optimizing outcomes for obese patients undergoing IVF. It provides valuable insights for anesthetic providers, reproductive specialists, and healthcare teams, emphasizing the need for a patient-centered approach to address the unique challenges posed by obesity in the context of assisted reproductive technology.

Pharmacokinetic relevance of glomerular hyperfiltration for drug dosing

In chronic kidney disease (CKD) patients, hypofiltration may lead to the accumulation of drugs that are cleared mainly by the kidney and, vice versa, hyperfiltration may cause augmented renal excretion of the same drugs. In this review we mainly focus on the issue of whether hyperfiltration significantly impacts the renal clearance of drugs and whether the same alteration may demand an up-titration of the doses applied in clinical practice. About half of severely ill, septic patients and patients with burns show glomerular hyperfiltration and this may lead to enhanced removal of drugs such as hydrophilic antibiotics and a higher risk of antibiotic treatment failure. In general, hyperfiltering obese individuals show higher absolute drug clearances than non-obese control subjects, but this depends on the body size descriptor adopted to adjust for fat excess. Several mechanisms influence pharmacokinetics in type 2 diabetes, including renal hyperfiltration, reduced tubular reabsorption and augmented tubular excretion. However, no consistent pharmacokinetic alteration has been identified in hyperfiltering obese subjects and type 2 diabetics. Non-vitamin K antagonist oral anticoagulants (NOACs) have exhibited lower plasma concentrations in hyperfiltering patients in some studies in patients with atrial fibrillation, but a recent systematic review failed to document any excess risk for stroke and systemic embolism in these patients. Hyperfiltration is common among severely ill patients in intensive care units and drug levels should be measured whenever possible in these high-risk patients to prevent underdosing and treatment failure. Hyperfiltration is also common in patients with obesity or type 2 diabetes, but no consistent pharmacokinetic alteration has been described in these patients. No NOAC dose adjustment is indicated in patients with atrial fibrillation being treated with these drugs.

Efficacy of Super-Bioavailable Itraconazole and Conventional Itraconazole at Different Dosing Regimens in Glabrous Tinea Infection - A Randomized Clinical Trial

Introduction

Itraconazole follows non-linear pharmacokinetics and hence is recommended once daily, but in real-world practice, is commonly prescribed as twice daily. Hence, this study aimed to evaluate the efficacy and safety of super-bioavailable-itraconazole-130 mg (SB-130) and conventional-itraconazole-200 mg (CITZ-200) once daily compared with conventional-itraconazole-100 mg (CITZ-100) twice daily in glabrous tinea.

Methods

A total of 261 eligible patients were enrolled in this prospective, randomized, clinical study from December-2021 to August-2022 at seven centers in India. Efficacy and safety assessments were done at week-3 and 6, with follow-up at week-10 for relapse. The primary objective was to assess the proportion of patients who achieved complete cure at week-6 following treatment in all itraconazole groups. The secondary outcomes were safety and clinical and mycological cure rates.

Results

Of 261 patients, 240 were included in the analysis. At week-6, 140 patients were completely cured; thus, overall cure rate was 58.33%. Fifty-five patients (69%) in SB-130 while 47/77 (61%) and 38/83 (46%) patients were completely cured in CITZ-200 and CITZ-100 groups respectively (p<0.05; SB-130: CITZ-100, p=0.32; SB-130: CITZ-200, p=0.058; CITZ-200: CITZ-100). There was no statistical difference in the mycological cure rate and area clearance rate between any of the groups (p=0.14); however, a statistically significant difference was noted for OD dosing over BD dosing in achieving clinical cure rates (p<0.05). A total of 13/140 patients (9%) relapsed following complete cure, with no statistically significant difference between any of the groups (p=0.50). All treatments were safe and well-tolerated, with no discontinuation.

Conclusion

In this clinical study, moderate efficacy with all doses of ITZ was reported but was better with OD dosing. Although there was no statistical difference between SB-130 and CITZ-200, SB-130 may be preferred over CITZ-200 owing to the advantage of SB over the conventional ITZ.

Body mass index as a predictor of the outcomes of acute clozapine toxicity: a cross-sectional study

Acute antipsychotic overdose is frequently reported nowadays. Clozapine is one of the atypical agents that are highly lipophilic, highly protein-bound, has a large volume of distribution, and accumulates in the brain and other tissues. Obesity is an essential factor controlling patients' treatment and clinical course. The current study aimed to study the prognostic value of body mass index (BMI) in patients with acute clozapine poisoning. All patients were evaluated on admission using the Poison Severity Score (PSS) and Glasgow Coma Score (GCS). The BMI was calculated. Mortality and the need for ICU admission were defined as primary outcomes, whereas secondary outcomes included cardiovascular complications and the need for mechanical ventilation. Thirty-eight patients presented with acute clozapine poisoning. The mean age of included patients was 25.2 ± 6. Patients were categorized regarding BMI into average weight (26.3%), overweight (31.6%), and obese (42.1%). Pearson's correlation indicated a significant positive correlation between BMI and respiratory rate (r = .364, p = .025). A significant negative correlation existed between BMI and GCS (r = .674, p ≤ .001). ROC curve reveals that BMI is an excellent predictor for the requirement of mechanical ventilation area under the curve (AUC > .9), a fair predictor of ICU admission AUC (.747). BMI had a sensitivity of 100% and specificity of 51.7 for the prediction of ICU admission. In conclusion, obesity increased the severity of toxicity and the incidence of poor clinical outcomes in patients with acute clozapine poisoning.

3D printing for personalised medicines: implications for policy and practice

The current healthcare dynamic has shifted from one-size-fits-all to patient-centred care, with our increased understanding of pharmacokinetics and pharmacogenomics demanding a switch to more individualised therapies. As the pharmaceutical industry remains yet to succumb to the push of a technological paradigm shift, pharmacists lack the means to provide completely personalised medicine (PM) to their patients in a safe, affordable, and widely accessible manner. As additive manufacturing technology has already established its strength in producing pharmaceutical formulations, it is necessary to next consider methods by which this technology can create PM accessible from pharmacies. In this article, we reviewed the limitations of current pharmaceutical manufacturing methods for PMs, three-dimensional (3D) printing techniques that are most beneficial for PMs, implications of bringing this technology into pharmacy practice, and implications for policy surrounding 3D printing techniques in the manufacturing of PMs.

The role of nutrition in children with cancer

In recent years, the influence of nutrition on the health and growth of children has become increasingly important. The relevance of nutrition is even greater for children who are facing cancer. Malnutrition, within the context of undernutrition and overnutrition, may impact not only the effectiveness of treatments and outcomes, but also the quality of life for patients and their families. In this article, we review nutritional assessment methods for children with cancer, focusing on the specific characteristics of this population and analyze the efficacy of nutritional interventions, which include enteral, parenteral, and nutritional education. From our analysis, two important conclusions emerged: i) there is a need to focus our attention on the nutritional status and the body composition of oncologic children, since these factors have a relevant impact on clinical outcomes during treatment as well as after their conclusion; ii) the support of skilled clinical nutrition personnel would be extremely helpful for the global management of these patients.

Vivarium Lighting as an Important Extrinsic Factor Influencing Animal-based Research

Light is an extrinsic factor that exerts widespread influence on the regulation of circadian, physiologic, hormonal, metabolic, and behavioral systems of all animals, including those used in research. These wide-ranging biologic effects of light are mediated by distinct photoreceptors, the melanopsin-containing intrinsically photosensitive retinal ganglion cells of the nonvisual system, which interact with the rods and cones of the conventional visual system. Here, we review the nature of light and circadian rhythms, current industry practices and standards, and our present understanding of the neurophysiology of the visual and nonvisual systems. We also consider the implications of this extrinsic factor for vivarium measurement, production, and technological application of light, and provide simple recommendations on artificial lighting for use by regulatory authorities, lighting manufacturers, designers, engineers, researchers, and research animal care staff that ensure best practices for optimizing animal health and wellbeing and, ultimately, improving scientific outcomes.

Chemotherapy and Anticancer Drugs Adjustment in Obesity: A Narrative Review

BACKGROUND

Obese individuals have higher rates of cancer incidence and cancer- related mortality. The worse chemotherapy outcomes observed in this subset of patients are multifactorial, including the altered physiology in obesity and its impact on pharmacokinetics, the possible increased risk of underdosing, and treatment-related toxicity.

AIMS

The present review aimed to discuss recent data on physiology, providing just an overall perspective and pharmacokinetic alterations in obesity concerning chemotherapy. We also reviewed the controversies of dosing adjustment strategies in adult and pediatric patients, mainly addressing the use of actual total body weight and ideal body weight.

METHODS

This narrative review tried to provide the best evidence to support antineoplastic drug dosing strategies in children, adolescents, and adults.

RESULTS

Cardiovascular, hepatic, and renal alterations of obesity can affect the distribution, metabolism, and clearance of drugs. Anticancer drugs have a narrow therapeutic range, and variations in dosing may result in either toxicity or underdosing. Obese patients are underrepresented in clinical trials that focus on determining recommendations for chemotherapy dosing and administration in clinical practice. After considering associated comorbidities, the guidelines recommend that chemotherapy should be dosed according to body surface area (BSA) calculated with actual total body weight, not an estimate or ideal weight, especially when the intention of therapy is the cure.

CONCLUSION

The actual total body weight dosing appears to be a better approach to dosing anticancer drugs in both adults and children when aiming for curative results, showing no difference in toxicity and no limitation in treatment outcomes compared to adjusted doses.

Effect of obesity on dolutegravir exposure in Black Southern African adults living with HIV

Background

Dolutegravir, a component of the preferred first-line antiretroviral therapy regimen, has been associated with increased weight gain. South Africa has a high prevalence of obesity, especially among women. Understanding dolutegravir exposure in patients with obesity is important for dose optimisation.

Objectives

We compared the pharmacokinetic parameters of dolutegravir in Southern African adults living with HIV with and without obesity.

Method

Blood samples were collected at various time points over a 24 h-period for dolutegravir assays. Non-compartmental analysis was conducted and geometric mean ratios (GMRs), with 90% confidence intervals (CIs), were generated to compare dolutegravir pharmacokinetic parameters between the groups. Regression analyses to assess predictors of dolutegravir exposure were done.

Results

Forty participants were enrolled, 26 were women and 10 had obesity. Dolutegravir area under the concentration-time curve to 24-h and the maximum concentrations were not statistically significantly lower in participants with obesity: GMR 0.91 (90% CI: 0.71-1.16) and GMR 0.86 (90% CI: 0.68-1.07), respectively. In a multivariate linear regression analysis adjusting for age, gender, body mass index, creatinine clearance and randomisation arm (tenofovir alafenamide or tenofovir disoproxil fumarate), a unit increase in body mass index was associated with 1.2% lower dolutegravir area under the concentration-time curve to 24-h (P = 0.035).

Conclusion

Dolutegravir exposure was marginally lower in participants with obesity, but this is not clinically significant. Our findings suggest that there is no need to dose adjust dolutegravir in people with obesity.

Application of a Volumetric Absorptive Microsampling (VAMS)-Based Method for the Determination of Paracetamol and Four of its Metabolites as a Tool for Pharmacokinetic Studies in Obese and Non-Obese Patients

BACKGROUND

The pharmacokinetic (PK) profile of a drug is influenced by several factors, which can lead to a suboptimal dosing regimen in specific patient populations. As obesity becomes increasingly prevalent, it is important that optimized dosing schemes are available for these patients. To set up such dosing schemes, PK studies should be performed in this population. Regarding paracetamol (acetaminophen [APAP]), obese patients would benefit from a tailored dosing scheme, as both the volume of distribution and metabolism are increased compared with non-obese patients. This includes metabolism by cytochrome P450 2E1, which is involved in APAP-associated hepatotoxicity. To decrease the burden for patients in these PK studies, finger-prick sampling could be used.

OBJECTIVE

The aim of this study was to compare the quantitative determination of APAP and four metabolites in different blood-based matrices and to determine if capillary dried blood samples, collected directly following finger-prick, could serve as a tool to investigate APAP PK in obese and non-obese patients.

METHODS

In this study, we performed a clinical validation of methods for the determination of APAP and four of its metabolites (APAP-glucuronide, APAP-sulfate, APAP-mercapturate, and APAP-cysteine) in blood, plasma, and dried blood. The latter was obtained by volumetric absorptive microsampling (VAMS), either starting from the venous blood or collected directly following a finger-prick. Results were compared between the different matrices and, in addition, blood:plasma (B:P) ratios were determined for the different analytes.

RESULTS

Liquid and dried venous blood results were in good agreement. Furthermore, differences between capillary (finger-prick) and venous VAMS blood samples remained limited for most analytes. However, for APAP-cysteine, caution should be paid to the interpretation of concentrations in (dried) blood. With the exception of APAP, concentrations were higher in plasma compared with blood, with B:P ratios ranging between 0.52 and 0.65. A time-dependent change in median B:P ratio was observed for APAP and APAP-cysteine. Additionally, a time-dependent trend was seen for APAP, as well as for APAP-glucuronide and APAP-mercapturate, for the distribution between capillary and venous blood.

CONCLUSIONS

We demonstrated that finger-prick sampling is a viable alternative to conventional venous blood sampling to investigate the PK of APAP and its metabolites in obese and non-obese patients.

Outcomes of modern antiretroviral therapy in obese individuals living with HIV

Obesity is a global epidemic and people living with HIV (PLWH) are showing similar obesity trends to those in the general population. Obesity is manifested by several physiological features that can alter volume of distribution, elimination and metabolism of various medications including ART. Some drugs are increasingly prone to pharmacokinetic alteration during obesity depending on their physicochemical properties and clearance mechanism. These considerations raise concerns of hampered efficacy, development of resistance or increased toxicity of ART in PLWH. Here, we summarize available literature on the exposure and antiviral outcomes of currently available antiretroviral drugs in the context of obesity and provide a panel of recommendations for the clinical management and follow-up in this growing patient population.

Obesity as a modifier of the cardiovascular effectiveness of sodium-glucose cotransporter-2 inhibitors in type 2 diabetes

AIMS

To assess the association between the use of sodium-glucose cotransporter-2 (SGLT2i) and cardiovascular outcomes and death as a function of obesity among patients with type 2 diabetes.

METHODS

This new-user, active-comparator cohort study used U.K.'s Clinical Practice Research Datalink linked to Hospital Episodes Statistics repository and Office for National Statistics. The cohort included 34,128 new-users of SGLT2i matched 1:1 to 34,128 new-users of dipeptidyl peptidase-4 inhibitors (DPP-4i) on body mass index and propensity score. Cox proportional hazards models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) of major adverse cardiovascular events (MACE), overall and in body mass index (BMI) categories (≤24.9 kg/m², 25.0-29.9 kg/m², 30.0-39.9 kg/m², ≥40 kg/m²). Secondary outcomes included all-cause mortality and hospitalization for heart failure.

RESULTS

SGLT2i were associated with a decreased risk of MACE (HR: 0.78, 95 %CI: 0.69-0.88) compared to DPP-4i. This decreased risk was most pronounced among obese and severely obese patients (HR: 0.77, 95 %CI: 0.66-0.91; HR: 0.67, 95% CI: 0.49-0.91, respectively) but not among overweight patients (HR: 0.94, 95 %CI: 0.73-1.22). Similar patterns were observed for cardiovascular mortality, all-cause mortality, and heart failure.

CONCLUSION

Compared with DPP-4i, the cardioprotective effect associated with SGLT2i is stronger among patients with higher BMI.

Influence of body fatness on propofol requirements for loss of consciousness in target-controlled infusion: A STROBE-compliant study

This prospective observational study evaluated the effects of body fat on the pharmacologic effect of propofol. Hundred patients aged 18 to 75 years who were scheduled to undergo orthopedic surgery under regional block were enrolled. All participants underwent bioelectrical impedance analysis and were allocated into 2 groups: the high and normal adiposity group, according to percent body fat. Following successful regional block, propofol was incrementally infused until loss of consciousness (LOC) with a target-controlled infusion pump. The effect-site concentration of propofol at LOC and the total infused dose of propofol per total body weight until LOC were recorded. At the end of the surgery, the infusion of propofol was stopped. The elapsed time to recovery of consciousness (ROC) and the effect-site concentration at ROC were recorded. These pharmacologic data were compared between 2 groups. The effect-site concentration of propofol at LOC (µg/mL) was significantly lower in the high adiposity group than in the normal group in both sexes (3.5 ± 0.4 vs 3.9 ± 0.6; P = .020 in males, and 3.4 [interquartile range: 2.9-3.5] vs 3.8 [interquartile range: 3.3-3.9]; P = .006 in females). Total dose per total body weight until LOC (mg/kg) were also significantly lower in the high adiposity group than in the normal group. There was no significant difference in the data related to ROC. The pharmacologic effects of propofol may be affected by the composition of body components. The concentration of propofol using a target-controlled infusion system may be diminished in patients with a high proportion of body fat.

Concentrations of Efavirenz, Tenofovir, and Emtricitabine in Obesity: A Cross-Sectional Study

BACKGROUND

Obesity is increasing worldwide including in people living with HIV (PLWH). Antiretroviral pharmacokinetic data in obesity are limited.

OBJECTIVES

To measure antiretroviral drug concentrations in obese and nonobese PLWH treated with the fixed-dose combination of efavirenz-tenofovir-emtricitabine. To determine pharmacokinetic differences across indicators of obesity and their associated immunovirological outcomes.

METHODS

We conducted a cross-sectional sample analysis of 2 cohort studies. We measured mid-dose efavirenz, 8-hydroxy-efavirenz, tenofovir, and emtricitabine concentrations. Antiretroviral drug concentrations were analyzed by body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR).

RESULTS

We performed a study of 213 participants: General obesity was detected in 20.4% using BMI and abdominal obesity in 53.6% using WC and 62.4% using WHR, respectively. The median concentrations of all antiretroviral drugs were lower among obese participants determined by BMI and WC, with efavirenz showing greater differences than tenofovir or emtricitabine. For BMI, results were most striking for efavirenz (1752.3 vs 2342.9 ng/mL, P = 0.002) with lower concentrations in obese participants. Using WC, efavirenz (1845.8 vs 2571.2 ng/mL, P < 0.001), tenofovir (65.8 vs 73.2 ng/mL, P = 0.036), and emtricitabine (159.5 vs 221.0 ng/mL, P = 0.005) concentrations were lower in obese participants. Eight-hydroxyefavirenz concentrations were similar in nonobese and obese participants for WC. Using WHR, the concentrations of all antiretroviral drugs were lower in the obese population, most strikingly for emtricitabine (173.5 vs 229.0 ng/mL, P = 0.015). There were no immunovirological associations.

CONCLUSION

We found lower antiretroviral concentrations in all obese groups, most strikingly in participants with abdominal obesity determined by WC. Lower drug concentrations had no immunovirological associations.

Impact of Body Mass Index on Muscle Strength, Thicknesses, and Fiber Composition in Young Women

High body mass index (BMI) may influence muscle strength, muscle thickness (Mtk), and fiber composition. We evaluated these parameters in 31 and 27 women grouped in non-oral contraceptive (non-OC) groups and OC groups, respectively, and further divided them into groups based on BMI: BMI_low, BMI_norm, and BMI_high. Maximum isometric force (F_max), Mtk, and the relative percentage of muscle fiber composition (%) were examined in both groups. F_max and Mtk values were significantly greater in the BMI_high than the BMI_low within the OC group. However, there was no significant difference in the non-OC group. BMI_low and BMI_norm groups showed a difference in the distribution of muscle fiber types 1 and 2 with almost the same proportions in both non-OC and OC groups. However, the BMI_high group showed a difference in the distribution of muscle fiber types 1 and 2, with type 1 about 18.76% higher in the non-OC group. Contrastively, type 2 was about 34.35% higher in the OC group. In this study, we found that there was a significant difference in F_max and Mtk according to the BMI level in the OC group, but no significant difference was found in the non-OC group. Moreover, the distribution of type 2 muscle fibers tended to be higher in the OC group of BMI_high, although the sample size was small. Therefore, although no significant difference of F_max and Mtk was found according to BMI level in the non-OC group in this study, the increase in BMI level appeared to be more associative of muscle strength in the OC group. Based on the present results, future studies are needed that consider the BMI level as well as the presence or absence of OC in future research about women's muscle strength.

Prophylactic Cefazolin Dosing in Obesity-a Systematic Review

Currently, there is no consensus on whether a standard 2-g prophylactic cefazolin dose provides sufficient antimicrobial coverage in obese surgical patients. This systematic review analysed both outcome and pharmacokinetic studies, aiming to determine the appropriate cefazolin dose. A systematic search was conducted using 4 databases. In total, 3 outcome and 15 pharmacokinetic studies met the inclusion criteria. All 3 outcome studies concluded that there is no need for increased dose. Also, 9 pharmacokinetic studies reached this conclusion; however, 6 pharmacokinetic studies recommended that 2-g dose is insufficient to achieve adequate plasma or tissue concentrations. The stronger body of evidence supports that 2-g dose of cefazolin is sufficient for surgery lasting up to 4 h; however, large-scale outcome studies are needed to confirm this evidence.

Dexamethasone exposure in normal-weight and obese hospitalized COVID-19 patients: An observational exploratory trial

During the latest pandemic, the RECOVERY study showed the benefits of dexamethasone (DEX) use in COVID-19 patients. Obesity has been proven to be an independent risk factor for severe forms of infection, but little information is available in the literature regarding DEX dose adjustment according to body weight. We conducted a prospective, observational, exploratory study at Geneva University Hospitals to assess the impact of weight on DEX pharmacokinetics (PK) in normal-weight versus obese COVID-19 hospitalized patients. Two groups of patients were enrolled: normal-weight and obese (body mass index [BMI] 18.5-25 and >30 kg/m2 , respectively). All patients received the standard of care therapy of 6 mg DEX orally. Blood samples were collected, and DEX concentrations were measured. The mean DEX AUC0-8 and Cmax were lower in the obese compared to the normal-weight group (572.02 ± 258.96 vs. 926.92 ± 552.12 ng h/ml and 138.67 ± 68.03 vs. 203.44 ± 126.30 ng/ml, respectively). A decrease in DEX AUC0-8 of 4% per additional BMI unit was observed, defining a significant relationship between weight and DEX AUC0-8 (p = 0.004, 95% CI 2-7%). In women, irrespective of the BMI, DEX AUC0-8 increased by 214% in comparison to men (p < 0.001, 95% CI 154-298%). Similarly, the mean Cmax increased by 205% in women (p < 0.001, 95% CI 141-297%). Conversely, no significant difference between the obese and normal-weight groups was observed for exploratory treatment outcomes, such as the length of hospitalization. BMI, weight, and gender significantly affected DEX AUC. We conclude that dose adjustment would be needed if the aim is to achieve the same exposures in normal-weight and obese patients.