Area under the concentration–time curve to minimum inhibitory concentration ratio as a predictor of vancomycin treatment outcome in methicillin-resistant Staphylococcus aureus bacteraemia

There have been few clinical studies on the association between the 24-h area under the concentration–time curve (AUC₂₄) to minimum inhibitory concentration (MIC) ratio and vancomycin treatment outcomes in methicillin-resistant Staphylococcus aureus (MRSA) infections. Patients with MRSA bacteraemia between July 2009 and January 2012 were analysed retrospectively. All adult patients treated with vancomycin for ≥72 h without dialysis were included. The MIC was determined by Etest and broth microdilution (BMD). Initial steady-state AUC₂₄ was estimated using a Bayesian model, and the AUC₂₄/MIC cut-off value for differentiating treatment success and failure was calculated by classification and regression tree (CART) analysis. In total, 76 patients were enrolled; vancomycin treatment failure occurred in 20 patients (26.3%). Catheter-related infection was the most frequent (35.5%), followed by surgical site infection (26.3%), whilst 25 (32.9%) had complicated infections. In univariate analysis, decreased MRSA vancomycin susceptibility (MIC ≥ 1.5 mg/L) and vancomycin trough levels (15–20 mg/L) were not associated with treatment outcomes. In the CART analysis, low initial vancomycin AUC₂₄/MIC (<430 by Etest; <398.5 by BMD) was associated with a higher treatment failure rate (50.0% vs. 25.0%, P = 0.039 by Etest; 45.0% vs. 23.2%; P = 0.065 by BMD). In multivariate analysis, low initial vancomycin AUC₂₄/MIC was a significant risk factor for treatment failure [adjusted odds ratio (aOR) = 4.39, 95% confidence interval (CI), 1.26–15.35 by Etest; aOR = 3.73, 95% CI 1.10–12.61 by BMD]. In MRSA bacteraemia, a low initial vancomycin AUC₂₄/MIC is an independent risk factor for vancomycin treatment failure.     

Media's effect on shaping knowledge,awareness risk perceptions and communication practices of pandemic COVID-19 among pharmacists

BackgroundCoronavirus disease (COVID-19), an infection of the zoonotic coronavirus, is presenting a healthcare challenge around the globe. This study aims to assess the levels of disease knowledge and risk perception among pharmacists. We also recognize predictors of risk perception and perceived media roles. Methods This is a questionnaire-base cross-sectional study. The questionnaire was developed on a web-based platform and invitations were sent to pharmacists nationwide to participate in the study using social media applications. Results A total of 486 pharmacists participated in this study, where females were dominant (78.6%, n = 382). Most (40.4%, n = 198) pharmacists scored 4 out of 5 in basic disease knowledge, and more than half were able to recognize common methods of spread. Risk was highly perceived among participants, and was predicted by gender, living area, and having children (p < 0,05). Frequency of watching the media and sources of information also influenced both risk perception and perceived media roles. Conclusion Disease awareness among pharmacists, as well as risk perception must be considered for effective risk communication planning. The role of media in shaping perceptions should also be carefully studied to encourage compliance with government containment measures and engagement in preventive behaviors.     

Renal pharmacists’ perceptions and current practices of assessing medication adherence in dialysis patients

Background Medication nonadherence is a major problem in chronic kidney failure patients undergoing dialysis. Pharmacists play a vital role in improving medication-related patient outcomes, reducing drug-related problems, and improving medication adherence. However, little is known about how pharmacists assess medication adherence in dialysis patients. Objective To measure pharmacists’ perceptions, current practices, and barriers to assessing adherence in dialysis patients. Setting Australian renal-specialised pharmacists. Method An online survey was conducted between March and May 2016. Survey included five psychometric scales measuring perceived prevalence, contributors, effective methods, barriers, and confidence to assess adherence on a 10-point Likert scale (1 = strongly disagree; 10 = strongly agree). Current practices were identified using a 4-point graded response (1 = do not practice; 4 = practice for all). Main outcome measure: Perception scores, scale reliability, and responses to current practices questionnaire. Results 41 pharmacists completed the survey (response rate, 91.1%). The majority (91.9%, n = 34; median = 8.0) agreed patients were nonadherent to medication. Time constraints (43.8%, n = 14) and hospital support (31.3%, n = 10) were perceived as barriers to assessment. Objective blood monitoring was frequently used to determine nonadherence (57.1%, n = 16), whereas subjective interviews were rarely conducted (27.6%, n = 8). Though all pharmacists support the presence of dedicated pharmacist for assessing adherence (100.0%, n = 33), only 24.2% were actually performing this function. Conclusion Pharmacists were rarely assigned for adherence assessment in dialysis settings. Established self-report methods were under-utilised compared to objective methods. Future research should investigate the effectiveness of pharmacists’ involvement in facilitating adherence promotion and early identification of medication-related issues in dialysis patients.

     

The dosing and monitoring of vancomycin: what is the best way forward?

We have evaluated the literature to review optimal dosing and monitoring of intravenous vancomycin in adults, in response to evolving understanding of targets associated with efficacy and toxicity. The area under the total concentration–time curve (0–24 h) divided by the minimum inhibitory concentration (AUC₂₄/MIC) is the most commonly accepted index to guide vancomycin dosing for the treatment of Staphylococcus aureus infections, with a value of 400 h a widely recommended target for efficacy. Upper limits of AUC₂₄ exposure of around 700 (mg/L).h have been proposed, based on the hypothesis that higher exposures of vancomycin are associated with an unacceptable risk of nephrotoxicity. If AUC₂₄/MIC targets are used, sources of variability in the assessment of both AUC₂₄ and MIC need to be considered. Current consensus guidelines recommend measuring trough vancomycin concentrations during intermittent dosing as a surrogate for the AUC₂₄. Trough concentrations are a misleading surrogate for AUC₂₄ and a poor end-point in themselves. AUC₂₄ estimation using log-linear pharmacokinetic methods based on two plasma concentrations, or Bayesian methods are superior. Alternatively, a single concentration measured during continuous infusion allows simple AUC₂₄ estimation and dose-adjustment. All of these methods have logistical challenges which must be overcome if they are to be adopted successfully.     

Desired vancomycin trough concentration to achieve an AUC0‐24/MIC ≥400 in Chinese children with complicated infectious diseases

A vancomycin steady‐state trough concentration (C_min) of 15‐20 mg/L is recommended for achieving a ratio of the 24‐hour area under the curve to the minimum inhibitory concentration (AUC_0‐24/MIC) of ≥400 in adults. Since few paediatric data are available, our objectives were to (a) measure the pharmacokinetic indices of vancomycin and (b) determine the correlation between C_min and AUC_0‐24/MIC in paediatric patients. Population‐based pharmacokinetic modelling was performed for paediatric patients to estimate the individual parameters. The relationship between C_min and the calculated AUC_0‐24/MIC was explored using linear regression and a probabilistic framework. A sensitivity analysis was also conducted using Monte Carlo simulations. Body‐weight significantly influenced the pharmacokinetics of vancomycin. Based on real data and simulations, C_min ranges of 5.0‐5.9 and 9.0‐12.9 mg/L were associated with AUC_0‐24/MIC ≥400 for MIC values of ≤0.5 and ≤1 mg/L, respectively. Vancomycin regimens of 10 and 15 mg/kg every 6 hours achieved a C_min of 5.0‐5.9 mg/L and AUC_0‐24/MIC ≥400 in >90% of the children when MIC was ≤0.5 mg/L. At a MIC of ≤1 mg/L, vancomycin at 15 mg/kg every 6 hours achieved C_min of 9.0‐12.9 mg/L and AUC_0‐24/MIC ≥400 in 2.0‐ and 1.6‐fold as many children compared to a dose of 10 mg/kg every 6 hours, respectively. Vancomycin C_min values of 5.0‐12.9 mg/L were strongly predictive of achieving AUC_0‐24/MIC ≥400, and rational dosing regimens of 10‐15 mg/kg q6h were required in paediatric patients, depending on the pathogen.     

Determination of vancomycin exposure target and individualised dosing recommendations for neonates: model-informed precision dosing

IntroductionFew studies incorporating population pharmacokinetic/pharmacodynamic (Pop-PK/PD) modelling have been conducted to quantify the exposure target of vancomycin in neonates. A retrospective observational cohort study was undertaken in neonates to determine this target and dosing recommendations (chictr.org.cn, ChiCTR1900027919).MethodsA Pop-PK model was developed to estimate PK parameters. Causalities between acute kidney injury (AKI) occurrence and vancomycin use were verified using Naranjo criteria. Thresholds of vancomycin exposure in predicting AKI or efficacy were identified via classification and regression tree analysis. Associations between exposure thresholds and clinical outcomes, including AKI and efficacy, were analysed by logistic regression. Dosing recommendations were designed using Monte Carlo simulations based on the optimised exposure target.ResultsPop-PK modelling included 182 neonates with 411 observations. On covariate analysis, neonatal physiological maturation, renal function and concomitant use of vasoactive agents (VAS) significantly affected vancomycin PK. Seven cases of vancomycin-induced AKI were detected. Area under the concentration-time curve from 0–24 hours (AUC_0–24) ≥ 485 mg?h/L was an independent risk factor for AKI after adjusting for VAS co-administration. The clinical efficacy of vancomycin was analysed in 42 patients with blood culture-proven staphylococcal sepsis. AUC_0–24 to minimum inhibitory concentration (AUC_0–24/MIC) ≥ 234 was the only significant predictor of clinical effectiveness. Monte Carlo simulations indicated that regimens in Neonatal Formulary 7 and Red Book (2018) were unsuitable for all neonates.ConclusionAn AUC_0–24 of 240–480 (assuming MIC = 1 mg/L) is a recommended exposure target of vancomycin in neonates. Model-informed dosing regimens are valuable in clinical practice.     

Informing a collaborative-care model for delivering medication assisted treatment for opioid dependence (MATOD): An analysis of pharmacist,prescriber and patient perceptions

BackgroundDemand for medication assisted treatment for opioid dependence (MATOD) in Australia exceeds capacity, particularly in rural and regional areas. There is increasing recognition that community pharmacists are well-positioned to take on expanded roles in MATOD delivery, however there has been limited Australian research exploring attitudes of pharmacists, prescribers, and patients to collaborative models of care.Objective(s)This study aimed to better understand enablers and barriers to a collaborative model for MATOD, to inform implementation in regions where increases in treatment capacity are urgently needed.MethodsSemi-structured telephone interviews were conducted with pharmacists (n = 11), prescribers (n = 6), and patients (n = 8) recruited from the Frankston-Mornington Peninsula region in Victoria, Australia, where transport and access to services have impacts on health care utilisation. The COM-B model was used to explore perceptions of pharmacists’ capability, opportunity, and motivations for delivering collaborative care.ResultsThere was strong motivation among healthcare professionals to participate in a collaborative model of care, with the main perceived benefits including improvements in accessibility, convenience, and continuity of care, and leverage of pharmacists’ high level of patient engagement. Key barriers identified by both pharmacists and prescribers included a perceived lack of pharmacist skills in some areas (capability) and resources (opportunity) to deliver collaborative care in a community pharmacy setting. Established relationships between all stakeholders (social opportunity) and communication between pharmacists and prescribers were identified as facilitators. Barriers and facilitators aligned with seven key areas: skills, confidence, relationships, patient selection, protocols, communication and resources.ConclusionsFindings informed the development of a collaborative model that was individualised, protocol based, and supported by training and clear processes.Project impactThis study identifies specific barriers and facilitators to a pharmacist-prescriber collaborative model of care for MATOD. The resulting model will be tested in a hybrid implementation-effectiveness trial in the Frankston-Mornington Peninsula region.     

Patient perception of community pharmacists prescribing pre-exposure prophylaxis for HIV prevention

ObjectiveThe primary objective of this study was to determine patients’ perceptions of pharmacists prescribing pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) prevention.DesignAn anonymous, 26-item, cross-sectional survey was administered to individuals and data collection occurred during a 12-week period from January to March 2019.Setting and participantsIndividuals were recruited to complete the survey in person at 5 locations of a large grocery-chain pharmacy in Washington, D.C. and Maryland. Inclusion criteria included individuals who were at least 18 years old and able to read and write English. Exclusion criteria included persons living with HIV or acquired immunodeficiency syndrome.Outcome measuresIn order to measure perception, participants were asked on the survey to select their level of agreement using a Likert scale from 1 to 5 (1 = strongly disagree, 5 = strongly agree). Researchers analyzed overall perception in addition to differences in perception based on various demographic characteristics.ResultsIn total, 117 surveys were collected and analyzed. Most participants were comfortable with pharmacists prescribing PrEP. Notable statistically significant findings included participants who interacted with pharmacists through medication therapy review (4.4, 3.1 [P < 0.05]) and vaccinations (4.3, 3.1 [P < 0.05]) were more likely to agree with pharmacists prescribing PrEP than participants who had no previous interactions with pharmacists. Participants who had previously used PrEP were more likely to agree with pharmacists prescribing PrEP than those who had not used PrEP before.ConclusionThis study provided a glimpse into patients’ perceptions of pharmacists prescribing PrEP. Patients were generally favorable of pharmacists prescribing PrEP; however, there are still barriers to overcome before prescribing PrEP for HIV prevention can feasibly occur in the community setting.     

Primary care provider perceptions of an integrated community pharmacy hypertension management program

BackgroundTrained community pharmacists provided hypertension (HTN) management services in collaboration with a patient-centered medical home (PCMH).ObjectiveTo explore primary care provider (PCP) perceptions of a HTN management program in which patients at the PCMH with elevated blood pressure could choose to receive follow-up care with a trained community pharmacist at a chain community pharmacy.MethodsWe conducted informal interviews with 8 PCPs with a range of level of involvement with the collaborative HTN management program to inform the development of a 13-question online survey that was distributed to PCPs at 10 participating Michigan Medicine PCMH clinics. The primary outcome was the percent of PCPs who reported that the program improved their patient’s blood pressure. Secondary outcomes included awareness of the program, alternative follow-up strategies, PCP satisfaction, and barriers to using the program.ResultsA total of 39 PCPs (30.0%) responded to the survey. More than one-half (n = 21 of 39, 53.9%) of respondents reported that at least 1 of their patients had seen a trained community pharmacist for HTN management services. Almost all of these PCPs (n = 19 of 21, 90.5%) reported being satisfied with the program, and 80.9% (n = 17 of 21) agreed that it helped patients improve their blood pressure control. The most common barriers identified were patients preferring to follow up directly with their PCP (n = 18 of 39, 46.2%), PCPs being more comfortable with patients having a visit with an embedded ambulatory care pharmacist (n = 16 of 39, 41.0%), and a lack of written materials to share with patients about the program (n = 15 of 39, 38.5%).ConclusionPCPs who used the integrated community pharmacy HTN management program were satisfied with the program and thought that it resulted in improved blood pressure control. PCPs may benefit from written information to share with their patients as well as education to increase their awareness of the program and its beneficial effect on patient blood pressure.     

Innovative learning in pharmacy practice: The perceived benefits of and barriers to a layered learning practice model

ObjectiveTo assess pharmacy preceptors’ perceptions of the benefits of and barriers to a layered learning practice model (LLPM) at their practice site.MethodsAn online survey was created using Qualtrics and sent to experiential directors at all colleges [or schools] of pharmacy in Ohio and at Big Ten universities. The experiential directors were asked to send the survey to all preceptors affiliated with their program. The survey assessed the perceived or actual benefits of and barriers to a layered learning model. Benefits and barriers to patient care, student or resident learning, and the practice site were assessed.ResultsIn total, 304 surveys were initiated by precepting pharmacists. Survey respondents reported precepting introductory pharmacy practice experience students (n = 113, 37.1%), advanced pharmacy practice experience students (n = 184, 60.5%), and residents (n = 176, 57.9%) throughout a given year. Survey respondents’ most commonly identified benefits of a LLPM included an increase in patient access to pharmacy team members (n = 97, 42.3%), an increase in the number of precepting opportunities for learners (n = 80, 34.9%), and improvement in patient education (n = 76, 33.2%). The top identified barriers to a LLPM included performing precepting duties that may interfere with preceptor job responsibilities (n = 158, 72.1%), having inadequate workspace for learners (n = 120, 54.8%), and being unable to effectively teach or oversee multiple learners simultaneously (n = 77, 35.1%).ConclusionsThis research provides insight into pharmacy preceptor perception of how a LLPM impacts practice sites, patient care, and training of pharmacy learners. This information may be valuable in the design of preceptor development for colleges of pharmacy and residency programs.     

Determining therapeutic trough ranges for linezolid

Linezolid (LZD) is an oxazolidinone approved for the treatment of gram-positive infections. Therapeutic drug monitoring is increasingly used to optimize LZD dosing. The therapeutic target for LZD is to achieve an area under the concentration-time curve over 24 h divided by the MIC (AUC/MIC) > 100. In this study, we determined the trough ranges associated with this therapeutic AUC. Concentration-time profiles for 999 virtual patients were simulated using a previously published pharmacokinetic model for LZD. AUC was estimated for each virtual patient using the trapezoidal method. We determined the trough ranges that achieve the therapeutic target of AUC/MIC > 100 at different MIC values of 1, 2 and 4 μg/mL. Trough samples correlated well with LZD AUC (R² = 0.87). For trough concentration of 2–5 μg/mL, 99% had an AUC_0–24 > 100 µg⋅h⋅ml⁻¹, 23% had an AUC_0–24 > 200 µg⋅h⋅ml⁻¹ and none had an AUC_0–24 > 400 µg⋅h⋅ml⁻¹. For trough concentrations of 5–8 µg/ml, 87% of the patients had an AUC_0–24 > 200 µg⋅h⋅ml⁻¹ and none had an AUC_0–24 > 400 µg⋅h⋅ml⁻¹ To achieve the therapeutic target of an AUC/MIC > 100, it is suggested that trough ranges be set at 2–5 µg/ml if the MIC < 2 and 5–8 µg/ml if the MIC = 2; however, at an MIC of 4 µg/ml, it is difficult to achieve an AUC/MIC > 100 without increasing the risk of LZD toxicity.     

Towards defining and supporting pharmacists' professional role associated with traditional and complementary medicines – A systematic literature review

BackgroundA review conducted in 2015 reported community pharmacists are willing to adopt a professional role in counselling consumers about the appropriate and safe use of traditional and complementary medicines (T&CM) but faced multiple barriers in doing so; including the role being poorly defined. This current review aimed to update and extend these findings, by identifying studies published since 2015 that reported on pharmacists across any setting.MethodsEligible studies published between January 01, 2016 and December 31, 2021 were identified across six databases (PubMed, Scopus, Web of Science, EMBASE, ScienceDirect and MEDLINE). A grounded theory approach was used to thematically synthesize the data extracted.FindingsA total 64 studies representing pharmacists across 30 countries were included for review. Study designs varied including cross-sectional surveys (n = 36), qualitative studies (n = 14), and pseudo-patient studies (n = 3). Eight studies reported on practice and/or bioethical responsibilities and 19 studies reported on factors that would enable pharmacists to fulfill these responsibilities, while 37 studies reported about both.ConclusionThese findings indicate research about pharmacists’ responsibilities associated with T&CM is evolving from gap analysis towards research that is proactive in advocating for change in multiple areas. These findings can be used to inform a consensus discussion among pharmacists and key stakeholders regarding a set of professional responsibilities that would serve in the development of: a clearly defined role and associated practice standards, and competency requirements that inform educational learning objectives for inclusion in undergraduate, post-graduate and continuing professional pharmacy education.     

Diabetes care in Qatar: a survey of pharmacists’ activities,attitudes and knowledge

Background Diabetes mellitus is recognized as a major public health issue and is one of the top ten causes of death in Qatar. Objective To describe the activities, and attitudes of Qatar pharmacists toward diabetes, to measure their diabetes knowledge and to assess their perceived barriers for diabetes care. Setting Community and ambulatory pharmacies in Qatar. Method Study objectives were addressed in a cross sectional survey of community and ambulatory pharmacists in Qatar. A phone call explaining the study was made to all community and ambulatory pharmacists in Qatar. Consenting pharmacists anonymously completed the survey either online or as paper. Main outcome measure Diabetes related activities, knowledge, attitudes and perceived barriers. Results Over 7 months, 126 surveys were collected (28% response rate). The majority of pharmacists always or often counselled patients on the appropriate time to take each medication and on medication side effects (90%, n = 100/111 and 73%, n = 81/111 respectively). Yet around 50% always or often provided education on the importance of screening for nephropathy (n = 59/112) and retinopathy (n = 58/109). In addition, 41% always or often provided education about the importance of immunization (n = 45/111) and 45% always or often provided therapy recommendations to physicians (n = 49/111). Using Diabetes Attitude Scale-3, most respondents had positive attitudes toward the need for special training, psychosocial impact of diabetes, and patient autonomy. Around 25% (n = 32/126) scored less than 6 out of 10 on the diabetes related knowledge test. The top three barriers for providing diabetes services were lack of time (53%, n = 67/126) shortage of personnel (42%, n = 53/126) and lack of private counseling area (42%, n = 53/126). Conclusion Qatar pharmacists mainly provide basic services for diabetic patients. They have an average diabetes related knowledge. Yet overall, they have positive attitudes toward diabetes, which is a vital component of any successful diabetes care service.

     

Roles and responsibilities of pharmacists with respect to natural health products: Key informant interviews

BackgroundAlthough many pharmacies sell natural health products (NHPs), there is no clear definition as to the roles and responsibilities (if any) of pharmacists with respect to these products.ObjectiveThe purpose of this study was to explore pharmacy and stakeholder leaders' perceptions of pharmacists' professional NHP roles and responsibilities.MethodsSemi-structured key informant interviews were conducted with pharmacy leaders (n = 17) and stakeholder (n = 18) leaders representing consumers, complementary and alternative medicine practitioners, conventional health care practitioners, and industry across Canada.ResultsAll participants believed a main NHP responsibility for pharmacists was in safety monitoring, although a one challenge identified in the interviews was pharmacists' general lack of NHP knowledge; however, stakeholder leaders did not expect pharmacists to be experts, but should have a basic level of knowledge about NHPs.ConclusionParticipants described pharmacists' professional roles and responsibilities for NHPs as similar to those for over-the-counter drugs; more awareness of existing NHP-related pharmacy policies is needed, and pharmacy owners/managers should provide additional training to ensure front-line pharmacists have appropriate knowledge of NHPs sold in the pharmacy.