Documentation of results and medication prescribing after combinatorial psychiatric pharmacogenetic testing: A case for discrete results

PURPOSE

Combinatorial pharmacogenetic (PGx) panels intended to aid psychiatric prescribing are available to clinicians. Here, we evaluated the documentation of PGx panel results and subsequent prescribing patterns within a tertiary health care system.

METHODS

We performed a query of psychiatry service note text in our electronic health record using 71 predefined PGx terms. Patients who underwent combinatorial PGx testing were identified, and documentation of test results was analyzed. Prescription data following testing were examined for the frequency of prescriptions influenced by genes on the panel along with the medical specialties involved.

RESULTS

A total of 341 patients received combinatorial PGx testing, and documentation of results was found to be absent or incomplete for 198 patients (58%). The predominant method of documentation was through portable document formats uploaded to the electronic health record's "Media" section. Among patients with at least 1 year of follow-up, a large majority (194/228, 85%) received orders for medications affected by the tested genes, including 132 of 228 (58%) patients receiving at least 1 non-psychiatric medication influenced by the test results.

CONCLUSION

Results from combinatorial PGx testing were poorly documented. Medications affected by these results were often prescribed after testing, highlighting the need for discrete results and clinical decision support.

Pharmacogenetics to prevent hypersensitivity reactions to antiepileptic drugs: is testing performed when indicated?

Extensive scientific evidence consistently demonstrates the clinical validity and utility of HLA-B*15:02 pre-screening in averting severe cutaneous adverse reactions (SCARs), namely Stevens-Johnson syndrome and toxic epidermal necrolysis, associated with carbamazepine or oxcarbazepine usage. Current practice guidelines and drug labeling actively advocate for pharmacogenetic pre-screening before initiating these antiepileptic drugs (AED), with particular emphasis on patients of Asian descent. However, there is a potential need to strengthen compliance with these recommendations. This retrospective study aimed to describe the pharmacogenetic pre-screening, documentation, and SCARs incidence for patients of Asian ancestry initiated on carbamazepine or oxcarbazepine at a large Northeastern USA healthcare system. Between 1 July 2016 and August 1, 2021, 27 patients with documented Asian heritage in the electronic health record (EHR) were included. The overall rate of HLA-B*15:02 pre-screening before carbamazepine or oxcarbazepine initiation was 4%. None who underwent pharmacogenetic pre-screening carried the associated HLA-B risk allele, and no SCARs were reported. Notably, pharmacogenetic results were not discretely entered into the EHR, and the results were only found as attached documents in the miscellaneous section of the EHR. There remains a significant opportunity for improving HLA-B*15:02 pre-screening for patients starting carbamazepine and oxcarbazepine to prevent SCARs in the USA.

Use of the Electronic Health Record for Monitoring Adverse Drug Reactions

PURPOSE OF REVIEW

Adverse drug reactions (ADRs) are a significant cause of morbidity and mortality. The electronic health record (EHR) provides an opportunity to monitor ADRs, mainly through the utilization of drug allergy data and pharmacogenomics. This review article explores the current use of the EHR for ADR monitoring and highlights areas that require improvement.

RECENT FINDINGS

Recent research has identified several issues with using EHR for ADR monitoring. These include the lack of standardization between EHR systems, specificity in data entry options, incomplete and inaccurate documentation, and alert fatigue. These issues can limit the effectiveness of ADR monitoring and compromise patient safety. The EHR has great potential for monitoring ADR but needs significant updates to improve patient safety and optimize care. Future research should concentrate on developing standardized documentation and clinical decision support systems within EHRs. Healthcare professionals should also be educated on the significance of accurate and complete ADR monitoring.

Clinical Pharmacogenetics Implementation Consortium (CPIC) Guideline for CYP2D6, CYP2C19, CYP2B6, SLC6A4, and HTR2A Genotypes and Serotonin Reuptake Inhibitor Antidepressants

Serotonin reuptake inhibitor antidepressants, including selective serotonin reuptake inhibitors (SSRIs; i.e., citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, and sertraline), serotonin and norepinephrine reuptake inhibitors (i.e., desvenlafaxine, duloxetine, levomilnacipran, milnacipran, and venlafaxine), and serotonin modulators with SSRI-like properties (i.e., vilazodone and vortioxetine) are primary pharmacologic treatments for major depressive and anxiety disorders. Genetic variation in CYP2D6, CYP2C19, and CYP2B6 influences the metabolism of many of these antidepressants, which may potentially affect dosing, efficacy, and tolerability. In addition, the pharmacodynamic genes SLC6A4 (serotonin transporter) and HTR2A (serotonin-2A receptor) have been examined in relation to efficacy and side effect profiles of these drugs. This guideline updates and expands the 2015 Clinical Pharmacogenetics Implementation Consortium (CPIC) guideline for CYP2D6 and CYP2C19 genotypes and SSRI dosing and summarizes the impact of CYP2D6, CYP2C19, CYP2B6, SLC6A4, and HTR2A genotypes on antidepressant dosing, efficacy, and tolerability. We provide recommendations for using CYP2D6, CYP2C19, and CYP2B6 genotype results to help inform prescribing these antidepressants and describe the existing data for SLC6A4 and HTR2A, which do not support their clinical use in antidepressant prescribing.

Evaluation of Potential Racial Disparities in CYP2C19-Guided P2Y12 Inhibitor Prescribing After Percutaneous Coronary Intervention

Black patients suffer worse outcomes after percutaneous coronary intervention (PCI) than White patients. Inequities in antiplatelet prescribing may contribute to this health disparity. We compared P2Y12 inhibitor prescribing by race following CYP2C19 genotyping to guide antiplatelet therapy selection after PCI. Patients from 9 sites that performed clinical CYP2C19 genotyping after PCI were included. Alternative therapy (e.g., prasugrel or ticagrelor) was recommended for CYP2C19 no-function allele carriers, in whom clopidogrel is predicted to be less effective. The primary outcome was choice of P2Y12 inhibitor (clopidogrel vs. alternative therapy) based on genotype. Of 3,342 patients included, 2,448 (73%) were White, and 659 (20%) were Black. More Black than White patients had a no-function allele (34.3% vs. 29.7%, P = 0.024). At hospital discharge following PCI, 44.2% of Black and 44.0% of White no-function allele carriers were prescribed alternative therapy. At the time of the last follow-up within 12 months, numerically fewer Black (51.8%) than White (56.7%) no-function allele carriers were prescribed alternative therapy (P = 0.190). However, the difference was not significant after accounting for other factors associated with P2Y12 inhibitor selection (odds ratio 0.79, 95% confidence interval 0.58-1.08). Alternative therapy use did not differ between Black (14.3%) and White (16.7%) patients without a no-function allele (P = 0.232). Among real-world patients who received CYP2C19 testing after PCI, P2Y12 inhibitor prescribing rates did not differ between Black and White patients. Our data suggest an absence of racial disparity in genotype-guided antiplatelet prescribing among patients receiving CYP2C19 testing.

High-Dimensional Neural Network Potential for Liquid Electrolyte Simulations

Liquid electrolytes are one of the most important components of Li-ion batteries, which are a critical technology of the modern world. However, we still lack the computational tools required to accurately calculate key properties of these materials (viscosity and ionic diffusivity) from first principles necessary to support improved designs. In this work, we report a machine learning-based force field for liquid electrolyte simulations, which bridges the gap between the accuracy of range-separated hybrid density functional theory and the efficiency of classical force fields. Predictions of material properties made with this force field are quantitatively accurate compared to experimental data. Our model uses the QRNN deep neural network architecture, which includes both long-range interactions and global charge equilibration. The training data set is composed solely of non-periodic density functional theory (DFT), allowing the practical use of an accurate theory (here, ωB97X-D3BJ/def2-TZVPD), which would be prohibitively expensive for generating large data sets with periodic DFT. In this report, we focus on seven common carbonates and LiPF₆, but this methodology has very few assumptions and can be readily applied to any liquid electrolyte system. This provides a promising path forward for large-scale atomistic modeling of many important battery chemistries.

Transferable Neural Network Potential Energy Surfaces for Closed-Shell Organic Molecules: Extension to Ions

Transferable high dimensional neural network potentials (HDNNPs) have shown great promise as an avenue to increase the accuracy and domain of applicability of existing atomistic force fields for organic systems relevant to life science. We have previously reported such a potential (Schrödinger-ANI) that has broad coverage of druglike molecules. We extend that work here to cover ionic and zwitterionic druglike molecules expected to be relevant to drug discovery research activities. We report a novel HDNNP architecture, which we call QRNN, that predicts atomic charges and uses these charges as descriptors in an energy model that delivers conformational energies within chemical accuracy when measured against the reference theory it is trained to. Further, we find that delta learning based on a semiempirical level of theory approximately halves the errors. We test the models on torsion energy profiles, relative conformational energies, geometric parameters, and relative tautomer errors.

705 CHARACTERISING OLDER ADULTS’ RISK OF HARM FROM BLOOD-PRESSURE LOWERING MEDICATIONS: A SUB-ANALYSIS FROM THE PRIME STUDY

Introduction

Hypertension is a major risk factor for cardiovascular disease and death. Randomised trials in older adults with relatively few co-morbidities recommend treatment of their hypertension [1]. However, blood-pressure lowering medications increase the risk of medication-related harm (MRH) from adverse drug reactions (ADRs), non-adherence, medication errors and drug–drug interactions. We aimed to identify characteristics associated with MRH in older people on blood-pressure lowering medications.

Method

The PRIME (prospective study to develop a model to stratify the risk of MRH in hospitalized elderly patients in the UK) study investigating the incidence and cost of MRH in 1280 older people in Southern England [2]. Adults ≥65 years were recruited from five teaching hospitals at hospital discharge and followed up for 8-weeks. Telephone interviews with study participants, review of primary care records and hospital readmissions were undertaken to identify MRH. PRIME study participants taking blood-pressure lowering medications, as defined by National Institute for Health and Care Excellence hypertension guidelines [3], were included in this analysis.

Results

Sixty-six percent of the PRIME cohort (n = 841) were taking blood-pressure lowering medications. Patients on four blood-pressure lowering medications were five times more likely to experience MRH compared to those taking just one medication (OR 4.96; 95%CI 1.63-15.13;p = 0.01). Most harm events were serious (80%,n = 123), requiring dose change or treatment cessation. Most MRH cases were potentially preventable (49%,n = 75).

Conclusion

MRH from blood-pressure lowering medication in older people is common, serious, and potentially preventable. Decisions around maximising cardiovascular risk reduction must be carefully considered in the context of MRH from blood-pressure lowering medications.

References

1. Sheppard JP, Lown M, Burt J et al. Generalizability of blood pressure lowering trials to older patients: cross-sectional analysis. J Am Geriatr Soc 2020; 68: 2508–15.

2. Parekh N, Ali K, Stevenson JM et al. Incidence and cost of medication harm in older adults following hospital discharge: a multicentre prospective study in the UK. Br J Clin Pharmacol 2018; 84: 1789–97.

3. National Institute for Health and Care Excellence (2019). Available at https://www.nice.org.uk/guidance/ng136. Accessed 27/11/2020.

CYP2C19 Genotype-Guided Antiplatelet Therapy After Percutaneous Coronary Intervention in Diverse Clinical Settings

Background Studies have demonstrated increased risk of major atherothrombotic events in CYP2C19 loss-of-function (LOF) variant carriers versus non-carriers treated with clopidogrel after percutaneous coronary intervention (PCI). We sought to evaluate real-world outcomes with the clinical implementation of CYP2C19-guided antiplatelet therapy after PCI. Methods and Results Data from 9 medical centers where genotyping was performed in the setting of PCI were included. Alternative therapy with prasugrel or ticagrelor was recommended for patients with a CYP2C19 LOF variant. The primary outcome was the composite of major atherothrombotic events (all-cause death, myocardial infarction, ischemic stroke, stent thrombosis, or hospitalization for unstable angina) within 12 months following PCI. Moderate or severe/life-threatening bleeding within 12 months was a secondary outcome. Among 3342 patients, 1032 (31%) were LOF carriers, of whom 571/1032 (55%) were treated with alternative therapy. In LOF carriers, the rate of major atherothrombotic events was lower in patients treated with alternative therapy versus clopidogrel (adjusted HR, 0.56; 95% CI 0.39-0.82). In those without a LOF allele, no difference was observed (adjusted HR, 1.07; 95% CI 0.71-1.60). There was no difference in bleeding with alternative therapy versus clopidogrel in either LOF carriers or those without a LOF allele. Conclusions Real-world data demonstrate lower atherothrombotic risk in CYP2C19 LOF carriers treated with alternative therapy versus clopidogrel and similar risk in those without a LOF allele treated with clopidogrel or alternative therapy. These data suggest that PCI patients treated with clopidogrel should undergo genotyping so that CYP2C19 LOF carriers can be identified and treated with alternative therapy.

Pharmacogenetics: A Precision Medicine Approach to Combatting the Opioid Epidemic

Ineffective pain control is the most commonly cited reason for misuse of prescription opioids and is influenced by genetics. In particular, the gene encoding the CYP2D6 enzyme, which metabolizes some of the most commonly prescribed opioids (e.g., tramadol, hydrocodone) to their more potent forms, is highly polymorphic and can lead to reduced concentrations of the active metabolites and decreased opioid effectiveness. Consideration of the CYP2D6 genotype may allow for predicting opioid response and identifying patients who are likely to respond well to lower potency opioids as well as those who may derive greater pain relief from non-opioid analgesics versus certain opioids. There is emerging evidence that a CYP2D6-guided approach to pain management improves pain control and reduces opioid consumption and thus may be a promising means for combating opioid misuse. Clinical practice guidelines are available for select opioids and other analgesics to support medication and dose selection based on pharmacogenetic data. This article describes the evidence supporting genotype-guided pain management as a means of improving pain control and reducing opioid misuse and clinical recommendations for genotype-guided analgesic prescribing. In addition, a "how to" guide using patient case examples is provided to demystify the process for implementing pharmacogenetics-guided pain management in order to optimize analgesia and minimize adverse effects. Optimizing pain management through genotype-guided approaches may ultimately provide safer and more effective therapy for pain control while decreasing the risk for opioid misuse.

Antiplatelet Therapy and Bleeding Outcomes With CYP2C19 Genotyping

PURPOSE

The impact of antiplatelet therapy with availability of CYP2C19 genotyping on bleeding in a real-world setting has not been extensively studied.

METHODS

Prospective, single-center, cohort study conducted between December 2015 and October 2019 with 1-year follow-up. Patients underwent percutaneous coronary intervention (PCI), CYP2C19 genotyping, and received P2Y12 inhibitor therapy. The primary outcome was time to first bleed of any severity using Bleeding Academic Research Consortium criteria. Secondary outcomes included time to first major bleed and rates of antiplatelet switching.

RESULTS

The primary outcome occurred in 697 of 2091 (33%) participants at a median of 15 days. Major bleeding occurred in 176 (8%) of patients. Compared to clopidogrel, treatment with ticagrelor or prasugrel was associated with increased risk of any bleeding (adjusted HR [aHR] 2.04, 95% CI 1.69-2.46). For patients without CYP2C19 no function alleles, treatment with prasugrel or ticagrelor was associated with increased risk of any bleeding (aHR 2.31, 95% CI 1.83-2.90). Similar associations were observed for major bleeding. No difference in ischemic events was observed. Among patients discharged on ticagrelor or prasugrel, 199 (36%) were de-escalated to clopidogrel within 1 year. De-escalation was more likely after a bleed if patients did not have a no function allele (35.9% vs 19.1%; P = .02).

CONCLUSION

Bleeding is common in post-PCI patients on antiplatelet therapy. Patients on high potency agents had higher bleeding risk in the population at-large and in non-carriers of CYP2C19 no function alleles. Genotype-guided antiplatelet de-escalation should be further explored in prospective studies.

Theoretical Study of Decomposition Kinetics and Thermochemistry of Bis(dimethylamino)silane-Formation of Methyleneimine and Silanimine Species

The gas-phase decomposition kinetics and thermochemistry of bis(dimethylamino)silane (BDMAS), a potential precursor in the chemical vapor deposition of silicon nitride and silicon carbonitride thin films, were systematically studied using ab initio calculations at the CCSD(T)/6-311 + G(2d,p)//B3LYP/6-311 + + G(d,p) level of theory. The reaction routes were mapped out, exploring both the concerted and stepwise reactions in three different zones with the initial cleavage of Si-N, N-Me (Me = CH₃), and Si-H, respectively. It was found that the energy needed to break N-Me at 80.6 kcal·mol^-1 is lower than the ones for Si-N and Si-H, both at 87.4 kcal·mol^-1. When compared with tris(dimethylamino)silane (TrDMAS), it has been shown that the three bonds of N-Me, Si-N, and Si-H in BDMAS can be ruptured more easily, suggesting that BDMAS could be a more efficient precursor gas than TrDMAS. Upon decomposition, BDMAS tends to form methyleneimine and silanimine species, where four methyleneimine species and three silanimine species were produced. From the investigation of the effect of temperature on the kinetic and thermodynamic competition of different decomposition pathways, it has been demonstrated that the concerted formation of N-dimethylaminosilyl methyleneimine (H₂C═N-SiH₂NMe₂) by the elimination of CH₄ from BDMAS is the most kinetically and thermodynamically favored pathway in the whole temperature range from 0 K (ΔH₀^‡ = 62.7 kcal·mol^-1 and ΔH₀ = 7.7 kcal·mol^-1) up to 2673 K. In addition, lower temperatures favor the production of N-methyl methyleneimime (H₂C═NMe), whereas high temperatures promote the formation of N-methylsilanimine (H₂Si = NMe) and 1-dimethylamino-N-methylsilanimine (Me₂NSi = NMe).

Genome-wide association study accounting for anticholinergic burden to examine cognitive dysfunction in psychotic disorders

Identifying genetic contributors to cognitive impairments in psychosis-spectrum disorders can advance understanding of disease pathophysiology. Although CNS medications are known to affect cognitive performance, they are often not accounted for in genetic association studies. In this study, we performed a genome-wide association study (GWAS) of global cognitive performance, measured as composite z-scores from the Brief Assessment of Cognition in Schizophrenia (BACS), in persons with psychotic disorders and controls (N = 817; 682 cases and 135 controls) from the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) study. Analyses accounting for anticholinergic exposures from both psychiatric and non-psychiatric medications revealed five significantly associated variants located at the chromosome 3p21.1 locus, with the top SNP rs1076425 in the inter-alpha-trypsin inhibitor heavy chain 1 (ITIH1) gene (P = 3.25×E-9). The inclusion of anticholinergic burden improved association models (P < 0.001) and the number of significant SNPs identified. The effect sizes and direction of effect of the top variants remained consistent when investigating findings within individuals receiving specific antipsychotic drugs and after accounting for antipsychotic dose. These associations were replicated in a separate study sample of untreated first-episode psychosis. The chromosome 3p21.1 locus was previously reported to have association with the risk for psychotic disorders and cognitive performance in healthy individuals. Our findings suggest that this region may be a psychosis risk locus that is associated with cognitive mechanisms. Our data highlight the general point that the inclusion of medication exposure information may improve the detection of gene-cognition associations in psychiatric genetic research.

How community pharmacists envision using pharmacogenomic data: A qualitative analysis

BACKGROUND

Nearly 300 medications contain pharmacogenomic information in their labeling approved by the U.S. Food and Drug Administration. As this number continues to grow, community pharmacists will be called on to use available pharmacogenomic data at the point of dispensing.

OBJECTIVE

This qualitative study aimed to describe how pharmacists envision the integration of pharmacogenomic data into the current workflows of community pharmacy practice.

METHODS

Community pharmacists from a regional supermarket chain pharmacy in the greater Pittsburgh area were interviewed using a semistructured interview guide. Participating pharmacists were presented with 3 clinical scenarios, followed by questions, to gain insight into how they envisioned the integration of pharmacogenomic data into community pharmacy workflow. The interview transcriptions were transcribed and coded. The content was analyzed to deduce the final themes. Supporting quotes were selected to illustrate each theme.

RESULTS

Ten community pharmacists from 3 different pharmacy locations participated in the study. A thematic analysis produced 6 themes: (1) integrating pharmacogenomic data into the dispensing software, (2) receiving an alert for pharmacogenomic information within the dispensing software, (3) accessing pharmacogenomic clinical guidelines to guide drug-decision-making, (4) contacting the prescriber by adding a task to the call queue, (5) placing a mandatory counseling alert on medications that were adjusted using pharmacogenomic data, and (6) counseling the patient on the first refill of a medication that was adjusted using pharmacogenomic data.

CONCLUSION

This study describes how pharmacists envisioned the integration of pharmacogenomic data into community pharmacy workflow. The participants sought the integration of pharmacogenomic data into existing dispensing software, alerts for actionable prescribing changes using patient-specific pharmacogenomic data when available, and access to clinical decision support. In addition, the participants preferred to engage prescribers and receive alerts to counsel patients at prescription pick-up. These findings are key to integrating pharmacogenomic data into community pharmacy practice.

Projected Utility of Pharmacogenomic Testing Among Individuals Hospitalized With COVID-19: A Retrospective Multicenter Study in the United States

Many academic institutions are collecting blood samples from patients seeking treatment for coronavirus disease 2019 (COVID‐19) to build research biorepositories. It may be feasible to extract pharmacogenomic (PGx) information from biorepositories for clinical use. We sought to characterize the potential value of multigene PGx testing among individuals hospitalized with COVID‐19 in the United States. We performed a cross‐sectional analysis of electronic health records from consecutive individuals hospitalized with COVID‐19 at a large, urban academic health system. We characterized medication orders, focusing on medications with actionable PGx guidance related to 14 commonly assayed genes (CYP2C19, CYP2C9, CYP2D6, CYP3A5, DPYD, G6PD, HLA‐A, HLA‐B, IFNL3, NUDT15, SLCO1B1, TPMT, UGT1A1, and VKORC1). A simulation analysis combined medication data with population phenotype frequencies to estimate how many treatment modifications would be enabled if multigene PGx results were available. Sixty‐four unique medications with PGx guidance were ordered at least once in the cohort (n = 1,852, mean age 60.1 years). Nearly nine in 10 individuals (89.7%) had at least one order for a medication with PGx guidance and 427 patients (23.1%) had orders for 4 or more actionable medications. Using a simulation, we estimated that 17 treatment modifications per 100 patients would be enabled if PGx results were available. The genes CYP2D6 and CYP2C19 were responsible for the majority of treatment modifications, and the medications most often affected were ondansetron, oxycodone, and clopidogrel. PGx results would be relevant for nearly all individuals hospitalized with COVID‐19 and would provide the opportunity to improve clinical care.

Impact of the CYP2C19*17 Allele on Outcomes in Patients Receiving Genotype-Guided Antiplatelet Therapy After Percutaneous Coronary Intervention

Genotyping for CYP2C19 no function alleles to guide antiplatelet therapy after percutaneous coronary intervention (PCI) improves clinical outcomes. Although results for the increased function CYP2C19*17 allele are also reported, its clinical relevance in this setting remains unclear. A collaboration across nine sites examined antiplatelet therapy prescribing and clinical outcomes in 3,342 patients after implementation of CYP2C19-guided antiplatelet therapy. Risk of major atherothrombotic and bleeding events over 12 months after PCI were compared across cytochrome P450 2C19 isozyme (CYP2C19) metabolizer phenotype and antiplatelet therapy groups by proportional hazards regression. Clopidogrel was prescribed to a similar proportion of CYP2C19 normal (84.5%), rapid (82.9%), and ultrarapid metabolizers (80.6%) (P = 0.360). Clopidogrel-treated normal metabolizers (20.4 events/100 patient-years; adjusted hazard ratio (HR) 1.00, 95% confidence interval (CI), 0.75-1.33, P = 0.993) and clopidogrel-treated rapid or ultrarapid metabolizers (19.1 events/100 patient-years; adjusted HR 0.95, 95% CI, 0.69-1.30, P = 0.734) exhibited no difference in major atherothrombotic events compared with patients treated with prasugrel or ticagrelor (17.6 events/100 patient-years). In contrast, clopidogrel-treated intermediate and poor metabolizers exhibited significantly higher atherothrombotic event risk compared with prasugrel/ticagrelor-treated patients (adjusted HR 1.56, 95% CI, 1.12-2.16, P = 0.008). When comparing clopidogrel-treated rapid or ultrarapid metabolizers to normal metabolizers, no difference in atherothrombotic (adjusted HR 0.97, 95% CI, 0.73-1.29, P = 0.808) or bleeding events (adjusted HR 1.34, 95% CI, 0.83-2.17, P = 0.224) were observed. In a real-world setting of genotype-guided antiplatelet therapy, the CYP2C19*17 allele did not significantly impact post-PCI prescribing decisions or clinical outcomes. These results suggest the CYP2C19 *1/*17 and *17/*17 genotypes have limited clinical utility to guide antiplatelet therapy after PCI.

Risk Factors for Cardiovascular Events in Patients on Antidementia Medications

OBJECTIVE

To identify characteristics associated with an increased risk of cardiovascular events in patients diagnosed with Alzheimer disease (AD) and treated with antidementia medications.

METHODS

Demographics, diagnoses, and medication usage of 30 433 Medicare patients were analyzed using 2006 to 2013 claims data and a combined model of screening, ranking and stepwise logistic regressions to evaluate factors associated with composite outcomes of 6 cardiovascular events.

RESULTS

Incidence rate of at least 1 cardiovascular event was 25.1%. Fifty-five factors were identified from the 10 381 candidate variables by the combined model with a c-statistic of 67% and an accuracy of 75%. Factors associated with increased risk of cardiovascular events include history of heart rhythm disorders, alteration of consciousness (odds ratio [OR]: 1.25; 95% confidence interval [CI]: 1.14-1.36), and usage of β-blockers (OR: 1.19; 95% CI: 1.13-1.27).

CONCLUSIONS

Clinicians should consider the increased risk of cardiovascular events in patients with AD with heart rhythm disorders and on β-blockers.

Effect of Selective Serotonin Reuptake Inhibitors on Cardiovascular Outcomes After Percutaneous Coronary Intervention: A Retrospective Cohort Study

BACKGROUND

Depression and coronary artery disease (CAD) are leading causes of death and disability and commonly co-occur. Different antidepressant classes have similar efficacy for depressed patients with CAD, but cardiovascular implications are unclear. Selective serotonin reuptake inhibitors (SSRIs) and mirtazapine are first-line options for depressed patients with CAD. SSRIs, but not mirtazapine, have known antiplatelet effects. Whether this affects risk of bleeding and major adverse cardiac events (MACE) in patients requiring dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) is unknown.

OBJECTIVE

The aim of this analysis is to examine the impact of SSRI treatment on the co-primary endpoints of composite MACE (death, myocardial infarction, or stroke) and composite bleeding events in patients treated with clopidogrel-based DAPT after PCI.

METHODS

We conducted a retrospective study with co-primary endpoints of bleeding and MACE within 1 year of PCI. Three groups were compared: SSRI patients, mirtazapine patients, and patients on neither agent. Mirtazapine acted as a comparator to control for depression, for which diagnosis coding was inadequate. Time-to-event analyses were performed with Kaplan-Meier estimators and adjusted analyses utilized Cox proportional hazards. There were 6874 (820 SSRI, 55 mirtazapine, 5999 neither) patients included.

RESULTS

SSRI patients had lower MACE risk than mirtazapine patients (hazard ratio [HR] 0.61, 95% confidence interval [CI] 0.38-0.97, p = 0.036) but higher MACE risk than patients on neither agent (HR 1.21, 95% CI 1.02-1.43, p = 0.030) in adjusted analyses. No significant differences were associated with bleeding risk (SSRI vs. neither adjusted HR 1.07, 95% CI 0.93-1.24, p = 0.36).

CONCLUSION

SSRI use was associated with a significant decrease in MACE rates compared with patients receiving mirtazapine. Bleeding risk was not affected by either antidepressant treatment. SSRIs may have cardioprotective benefits compared with mirtazapine.

Multisite Investigation of Strategies for the Implementation of CYP2C19 Genotype-Guided Antiplatelet Therapy

CYP2C19 genotype-guided antiplatelet therapy following percutaneous coronary intervention is increasingly implemented in clinical practice. However, challenges such as selecting a testing platform, communicating test results, building clinical decision support processes, providing patient and provider education, and integrating methods to support the translation of emerging evidence to clinical practice are barriers to broad adoption. In this report, we compare and contrast implementation strategies of 12 early adopters, describing solutions to common problems and initial performance metrics for each program. Key differences between programs included the test result turnaround time and timing of therapy changes, which are both related to the CYP2C19 testing model and platform used. Sites reported the need for new informatics infrastructure, expert clinicians such as pharmacists to interpret results, physician champions, and ongoing education. Consensus lessons learned are presented to provide a path forward for those seeking to implement similar clinical pharmacogenomics programs within their institutions.

Multisite Investigation of Outcomes With Implementation of CYP2C19 Genotype-Guided Antiplatelet Therapy After Percutaneous Coronary Intervention

OBJECTIVES

This multicenter pragmatic investigation assessed outcomes following clinical implementation of CYP2C19 genotype-guided antiplatelet therapy after percutaneous coronary intervention (PCI).

BACKGROUND

CYP2C19 loss-of-function alleles impair clopidogrel effectiveness after PCI.

METHODS

After clinical genotyping, each institution recommended alternative antiplatelet therapy (prasugrel, ticagrelor) in PCI patients with a loss-of-function allele. Major adverse cardiovascular events (defined as myocardial infarction, stroke, or death) within 12 months of PCI were compared between patients with a loss-of-function allele prescribed clopidogrel versus alternative therapy. Risk was also compared between patients without a loss-of-function allele and loss-of-function allele carriers prescribed alternative therapy. Cox regression was performed, adjusting for group differences with inverse probability of treatment weights.

RESULTS

Among 1,815 patients, 572 (31.5%) had a loss-of-function allele. The risk for major adverse cardiovascular events was significantly higher in patients with a loss-of-function allele prescribed clopidogrel versus alternative therapy (23.4 vs. 8.7 per 100 patient-years; adjusted hazard ratio: 2.26; 95% confidence interval: 1.18 to 4.32; p = 0.013). Similar results were observed among 1,210 patients with acute coronary syndromes at the time of PCI (adjusted hazard ratio: 2.87; 95% confidence interval: 1.35 to 6.09; p = 0.013). There was no difference in major adverse cardiovascular events between patients without a loss-of-function allele and loss-of-function allele carriers prescribed alternative therapy (adjusted hazard ratio: 1.14; 95% confidence interval: 0.69 to 1.88; p = 0.60).

CONCLUSIONS

These data from real-world observations demonstrate a higher risk for cardiovascular events in patients with a CYP2C19 loss-of-function allele if clopidogrel versus alternative therapy is prescribed. A future randomized study of genotype-guided antiplatelet therapy may be of value.

Sex-based differences in lifting technique under increasing load conditions: A principal component analysis

The objective of the present study was to determine if there is a sex-based difference in lifting technique across increasing-load conditions. Eleven male and 14 female participants (n = 25) with no previous history of low back disorder participated in the study. Participants completed freestyle, symmetric lifts of a box with handles from the floor to a table positioned at 50% of their height for five trials under three load conditions (10%, 20%, and 30% of their individual maximum isometric back strength). Joint kinematic data for the ankle, knee, hip, and lumbar and thoracic spine were collected using a two-camera Optotrak motion capture system. Joint angles were calculated using a three-dimensional Euler rotation sequence. Principal component analysis (PCA) and single component reconstruction were applied to assess differences in lifting technique across the entire waveforms. Thirty-two PCs were retained from the five joints and three axes in accordance with the 90% trace criterion. Repeated-measures ANOVA with a mixed design revealed no significant effect of sex for any of the PCs. This is contrary to previous research that used discrete points on the lifting curve to analyze sex-based differences, but agrees with more recent research using more complex analysis techniques. There was a significant effect of load on lifting technique for five PCs of the lower limb (PC1 of ankle flexion, knee flexion, and knee adduction, as well as PC2 and PC3 of hip flexion) (p < 0.005). However, there was no significant effect of load on the thoracic and lumbar spine. It was concluded that when load is standardized to individual back strength characteristics, males and females adopted a similar lifting technique. In addition, as load increased male and female participants changed their lifting technique in a similar manner.

Genetic determinants of selective serotonin reuptake inhibitor related sexual dysfunction

Sexual dysfunction is a troubling obstacle for individuals being treated for depression and can be caused by both depressive symptoms as well as antidepressant drugs. Selective serotonin reuptake inhibitors (SSRIs) represent a class of antidepressants commonly associated with sexual dysfunction, even after symptomatic improvement. Candidate gene studies have identified associations between sexual dysfunction and altered SSRI pharmacokinetics or to the neurotransmitter systems affected by depression and SSRI treatment. The multifactorial nature of this phenotype and study heterogeneity are currently limitations to the translation of these findings to clinical use. Larger, prospective studies of genetic-guided antidepressant selection may help to clarify the clinical utility of pharmacogenetics in minimizing sexual side effects.

Echinacea purpurea significantly induces cytochrome P450 3A activity but does not alter lopinavir-ritonavir exposure in healthy subjects

STUDY OBJECTIVE

. To determine the influence of Echinacea purpurea on the pharmacokinetics of lopinavir-ritonavir and on cytochrome P450 (CYP) 3A and P-glycoprotein activity by using the probe substrates midazolam and fexofenadine, respectively.

DESIGN

Open-label, single-sequence pharmacokinetic study.

SETTING

Outpatient clinic in a federal government research center.

SUBJECTS

Thirteen healthy volunteers (eight men, five women).

INTERVENTION

Subjects received lopinavir 400 mg-ritonavir 100 mg twice/day with meals for 29.5 days. On day 16, subjects received E. purpurea 500 mg 3 times/day for 28 days: 14 days in combination with lopinavir-ritonavir and 14 days of E. purpurea alone. In order to assess CYP3A and P-glycoprotein activity, subjects received single oral doses of midazolam 8 mg and fexofenadine 120 mg, respectively, before and after the 28 days of E. purpurea.

MEASUREMENTS AND MAIN RESULTS

On days 15 and 30 of lopinavir-ritonavir administration (before and after E. purpurea administration, respectively), serial blood samples were collected over 12 hours to determine lopinavir and ritonavir concentrations and subsequent pharmacokinetic parameters by using noncompartmental methods. Neither lopinavir nor ritonavir pharmacokinetics were significantly altered by 14 days of E. purpurea coadministration. The post-echinacea: pre-echinacea geometric mean ratios (GMRs) for lopinavir area under the concentration-time curve (AUC) from 0-12 hours and for maximum concentration were 0.96 (90% confidence interval [CI] 0.83-1.10, p=0.82) and 1.00 (90% CI 0.88-1.12, p=0.72), respectively. Conversely, GMRs for midazolam AUC from time zero extrapolated to infinity and oral clearance were 0.73 (90% CI 0.61-0.85, p=0.008) and 1.37 (90% CI 1.10-1.63, p=0.02), respectively. Fexofenadine pharmacokinetics did not significantly differ before and after E. purpurea administration (p>0.05).

CONCLUSION

Echinacea purpurea induced CYP3A activity but did not alter lopinavir concentrations, most likely due to the presence of the potent CYP3A inhibitor, ritonavir. Echinacea purpurea is unlikely to alter the pharmacokinetics of ritonavir-boosted protease inhibitors but may cause modest decreases in plasma concentrations of other CYP3A substrates.

Ertapenem clearance during modeled continuous renal replacement therapy

PURPOSE

To determine ertapenem transmembrane clearance (CLtm) during continuous renal replacement therapy (CRRT) using a validated in vitro model.

METHODS

Ertapenem clearance during continuous hemofiltration and hemodialysis was assessed with AN69 and polysulfone hemodiafilters at 4 dialysate (Qd) and ultrafiltration rates (Quf): 1, 2, 3, and 6 l/hour. Blood and dialysate samples were collected at each flow rate and assayed for urea (control solute) and ertapenem concentrations. The experiment was repeated 5 times for each hemodiafilter type. Ertapenem and urea sieving coefficient (SC) and saturation coefficient (SA) were assessed, and CLtm calculated.

RESULTS

In continuous hemofiltration mode, urea and ertapenem SC ranged from 1.00 to 1.19 at all Quf and did not differ between hemodiafilter types. Consequently, convective CLtm also did not differ between hemodiafilters. In continuous dialysis mode, urea Cltm did not differ between hemodiafilter types at any Qd. However, ertapenem SA and CLtm were significantly different between hemodiafilter types at Qd 6l/hour (p<0.001). As Qd increased, mean +/- SD AN69 SA declined significantly from 0.87 +/- 0.12 at Qd 1 l/hour to 0.45 +/- 0.02 at Qd 6 l/hour (p<0.001). Ertapenem SA did not differ at any Qd with the polysulfone hemodiafilter (range 0.71-0.80).

CONCLUSION

Ertapenem was cleared substantially in these in vitro CRRT models. However, our findings illustrate discordance between our observed SC and SA and the published unbound fraction of ertapenem. This finding has been reported with many other drugs, including carbapenem antibiotics. If in vivo studies corroborate our SA and SC findings, dosage adjustment for patients receiving CRRT will be required.

Biomechanical assessment of lateral stiffness elements in the suspension system of a backpack

The purpose of this study was to examine the change in load distribution characteristics associated with adding lateral stiffness elements (rods) to a rucksack (backpack). A load distribution mannequin was instrumented with two 3D load cells to allow determination of the load applied to the shoulders and upper torso independent of the load applied to the hips and lower trunk. Position and mass of the payload (25 kg) were fixed at the centre of the volume of the rucksack and held constant during all testing. It was hypothesized that lateral rods would provide a force bridge that transfers part of the vertical load of the pack from the upper back and shoulders to the hip belt thereby reducing the vertical load on the torso, and possibly reducing the horizontal reaction force that produces a shear load on the spine. Results showed that these active stiffness elements shifted 14% of the vertical load from the upper torso to the pelvic region with lumbar shear load remaining relatively unchanged for all combinations of shoulder strap and waist belt tension. The lateral rods also provided a mean increase of 12% in the extensor moment at the L3-L4 level, thus reducing some demand on the erector spinae muscles.

A suite of objective biomechanical measurement tools for personal load carriage system assessment

For application to military and civilian needs, Defence Research and Development Canada--Toronto contracted Queen's University, Kingston to develop a suite of biomechanical assessment and analytical tools to supplement human-based load carriage system assessment methods. This suite of tools permitted efficient objective evaluation of biomechanical aspects of load-bearing webbing, vests, packs and their components, and therefore contributed to early system assessment and a rapid iterative design process. This paper is a summary of five assessment and analytical tools. A dynamic load carriage simulator was developed to simulate cadence of walking, jogging and running. The simulator comprised a computer-controlled pneumatic platform that oscillated anthropometrically weighted mannequins of varying dimensions from which measures of skin contact pressure, hip reaction forces and moments and relative pack-person displacements were taken. A stiffness tester for range of motion provided force-displacement data on pack suspension systems. A biomechanical model was used to determine forces and moments on the shoulders and hips, and validated using a static load distribution mannequin. Subjective perceptual rating systems were used gather soldier feedback during a standardized mobility circuit. Objective outcome measures were validated by means of other objective measures (e.g., Optotrak, video, Instron, etc.) and then compared to subjective ratings. This approach led to development of objective performance criteria for load carriage systems and to improvements in load carriage designs that could be used both in the military and in general.

Branded versus generic clozapine for treatment of schizophrenia

OBJECTIVE

To report clinical findings resulting from a switch from branded to generic clozapine.

METHODS

Twenty patients diagnosed with schizophrenia were followed in this naturalistic outpatient study. The Positive and Negative Syndrome Scale (PANSS), Beck Anxiety Inventory (BAI), Abnormal Involuntary Movement Scale, and the Movement Disorder Assessment were used to assess differences in the clinical status of patients before and after switching from Clozaril to generic clozapine (Mylan Pharmaceuticals). Results were analyzed by means of the paired t-test and by calculation of the percent change in mean scores. A clinically significant change as measured by the PANSS was defined as a +/- 20% change in mean scores at final evaluation. The design was open-label and non-blinded.

RESULTS

At the final evaluation, the t-test revealed no significant differences between branded and generic clozapine for the total PANSS, the positive symptom, negative symptom, and the general psychopathology subscales of the PANSS, and the BAI. There were no clinically significant changes for any measure.

CONCLUSIONS

In this small group of patients with schizophrenia, no deterioration in clinical status in several domains was noted after changing from branded to generic clozapine. This finding is consistent with pharmacologic data suggesting bioequivalence of the 2 products. Results, however, must be interpreted cautiously due to the lack of optimal study controls and small sample size.

Impact of multiple injections on immunization rates among vulnerable children

BACKGROUND

In 1997, the Advisory Committee on Immunization Practices (ACIP) recommended a switch from oral polio vaccine (OPV) to inactivated polio vaccine (IPV) for the first two infant doses. The ACIP also recommended use of diphtheria, tetanus, and acellular pertussis vaccine (DTaP) for infants. These recommendations resulted in two additional injections at the 2- and 4-month immunization visits. This study evaluates the implementation of new IPV and DTaP immunization recommendations and their impact on immunization coverage levels.

METHODS

Immunization coverage was assessed in public clinics in three urban areas before and after the recommendations. One pre- and three post-recommendation cohorts were followed to 12 months of age.

RESULTS

Almost all (> or = 88%) infants in the pre-recommendation cohort received OPV, DTP, and only one or two injections. Almost all (> or = 78%) infants in the post-recommendation cohorts received IPV, DTaP, and three or four injections. The percentage of infants in the post-recommendation cohorts up-to-date for immunizations at 12 months of age was slightly higher than those in the pre-recommendation cohort.

CONCLUSIONS

Providers rapidly switched from OPV and DTP to IPV and DTaP. Coverage at 12 months of age was higher among IPV/DTaP recipients than among OPV/DTP recipients. Provider and parent acceptance of four injections at a visit was high. The recent pneumococcal conjugate vaccine recommendations potentially add a fifth injection at 2 and 4 months of age. Acceptance or rejection of five injections by providers and parents needs early assessment.

Binding site elucidation of hydantoin-based antagonists of LFA-1 using multidisciplinary technologies: evidence for the allosteric inhibition of a protein--protein interaction

The binding site on the lymphocyte function-associated antigen-1 (LFA-1) of a class of hydantoin-based antagonists of leukocyte cell adhesion has been identified. This site resides in the inserted-domain (I-domain) of the CD11a chain at a location that is distal to residues known to be required for interactions with the intercellular adhesion molecules. This finding supports the hypothesis that the molecules are antagonizing cell adhesion via an allosteric modification of LFA-1. The binding site was identified using an integrated immunochemical, chemical, and molecular modeling approach. Antibodies that map to epitopes on the I-domain were blocked from binding to the purified protein by the hydantoins, indicating that the hydantoin-binding site resides on the I-domain. Photoaffinity labeling of the I-domain followed by LC/MS and LC/MS/MS analysis of the enzymatic digest identified proline 281 as the primary amino acid residue covalently attached to the photoprobe. Distance constraints derived from this study coupled with known SAR considerations allowed for the construction of a molecular model of the I-domain/inhibitor complex. The atomic details of the protein/antagonist interaction were accurately predicted by this model, as subsequently confirmed by the X-ray crystal structure of the complex.

A longitudinal study of the development of low back pain in an industrial population

STUDY DESIGN

This is a longitudinal study in which industrial workers without chronic low back pain (LBP) were initially assessed with a comprehensive test battery and surveyed every 6 months thereafter for 2 years.

OBJECTIVE

To determine factors that may predispose industrial workers who lift over 5000 kg per shift to LBP.

SUMMARY OF BACKGROUND DATA

Prospective studies are small in number and often limited in breadth or depth of the test battery, methodologic issues, or investigator expertise. There are no prospective studies that focus on a homogeneous work sample of industrial employees.

METHODS

Production workers (n = 149) who volunteered for the 2-year study were assessed using physical measures (e.g., muscular strength, endurance, and flexibility), lifting kinematics (a sagittal plane box lift), and health, lifestyle, and work environment data (paper questionnaires). Follow-up questionnaires were distributed every 6 months for 2 years.

RESULTS

Using self-report of LBP as the main outcome measure, eight variables predicted LBP in this sample with a 75% correct prediction rate. Predictor variables included age, thoracic acceleration during the trunk velocity test, median frequency intercept of electromyography of the right L3 erector spinae, quadriceps strength, quadriceps endurance, self-assessment of fitness, having a confidante, and number of medications currently taken.

CONCLUSION

Results confirmed the multifactorial nature of low back pain and suggest that personal fitness is an important defense against low back pain, even in manual handling lifting tasks.

Back fitness and back health assessment considerations for the Canadian Physical Activity, Fitness and Lifestyle Appraisal

The Canadian Physical Activity, Fitness, and Lifestyle Appraisal (CPAFLA) is used as a measure for the health-related fitness of the general population. The CPAFLA includes an evaluation of back health, which is comprised of abdominal muscular endurance (partial curl-ups) and trunk flexion (sit and reach). This paper reviews the occupational, lifestyle, and physical risks associated with back pain and examines the measurement techniques used to assess health-related fitness components of back health in fitness assessments, such as the CPAFLA. Recommendations for future revisions of the CPACFLA's back health assessment and future research needs are presented.

Vaccination status of children in the Women, Infants, and Children (WIC) Program: are we doing enough to improve coverage?

BACKGROUND

Vaccination-promoting strategies in the Supplemental Nutrition Program for Women, Infants, and Children (WIC) have been shown to produce dramatic improvements in coverage and other health outcomes.

OBJECTIVES

To determine national and state-specific population-based vaccine coverage rates among preschool children who participate in the WIC program, and to describe the strategies for promoting vaccination in WIC.

DESIGN/METHODS

Demographic data, WIC participation, and vaccination histories for children aged 24 to 35 months in 1999 were collected from parents through the National Immunization Survey. The healthcare providers for the children in the survey were contacted to verify and complete vaccination information. We defined children as up-to-date (UTD) if they had received four doses of diphtheria and tetanus toxoids and pertussis vaccine (DPT), three doses of poliovirus vaccine, one dose of measles-mumps-rubella vaccine (MMR), and three doses of Haemophilus influenzae type b vaccine (Hib) by 24 months. Description of state-level vaccination-promoting activities in WIC was collected through an annual survey completed by the state WIC and immunization program directors.

RESULTS

Complete data were collected on 15,766 children, of whom 7783 (49%) participated in WIC sometime in their lives. Nationally, children who had ever participated in WIC were less well-immunized at 24 months compared to children who had not: 72.9% UTD (95% CI, 71.3-74.5) versus 80.8% UTD (95% CI, 79.5-82.1), respectively. In 42 states, 24-month coverage among WIC participants was less than among non-WIC participants, including 13 states where the difference was > or = 10%. Vaccination activities linked with WIC were reported from 76% of 8287 WIC sites nationwide. States conducting more-frequent interventions and reaching a higher proportion of WIC participants had 40% higher vaccination coverage levels for the WIC participants in that state (p<0.05).

CONCLUSIONS

Children served by WIC remain less well-immunized than the nation's more-affluent children who do not participate in WIC. Thus, WIC remains a good place to target these children. This study provides evidence that fully implemented WIC linkage works to improve vaccination rates. Strategies that have been shown to improve the vaccination coverage levels of WIC participants should be expanded and adequately funded to protect these children.

Performance of US hospitals on recommended screening and immunization practices for pregnant and postpartum women

OBJECTIVE

Recommendations by most national advisory committees on immunization include evaluating all pregnant women for chronic hepatitis B virus infection and immunity to rubella. It is recommended that all pregnant women be screened for hepatitis B surface antigen during an early prenatal visit and that rubella vaccine be administered in the postpartum period to women not known to be immune. This study determined the extent to which hospitals with labor and delivery services adhere to these recommendations.

METHODS

We conducted a mail survey of a stratified random sample of all US medical-surgical hospitals to (1) determine the proportion of hospitals with hepatitis B screening policies and rubella immunization programs and (2) identify significant factors associated with the presence of these policies and programs. Hospitals were stratified by number of beds (<100, 100-499, and > or =500) and affiliation with a medical school.

RESULTS

Of 986 institutions surveyed, 858 (87%) responded. Of these, 635 (74%) were labor and delivery hospitals. Approximately half of these (51%) had hospital policies related to screening pregnant women for the hepatitis B surface antigen. Twenty-one percent had rubella immunization programs for postpartum women. Only 14% of labor and delivery hospitals were in full compliance with published recommendations for hepatitis B surface antigen screening and rubella postpartum vaccination. Hospitals were more likely to be compliant if they had more than 100 beds, were private rather than public institutions, were affiliated with a medical school, and were in states with laws regarding hepatitis B surface antigen screening of pregnant women.

CONCLUSIONS

Almost half, and more than three quarters, of hospitals were not in compliance with hepatitis B screening and rubella postpartum immunization recommendations, respectively. Hospitals should develop and implement policies for these preventive services.

Inositol signaling and plant growth

Living organisms have evolved to contain a wide variety of receptors and signaling pathways that are essential for their survival in a changing environment. Of these, the phosphoinositide pathway is one of the best conserved. The ability of the phosphoinositides to permeate both hydrophobic and hydrophilic environments, and their diverse functions within cells have contributed to their persistence in nature. In eukaryotes, phosphoinositides are essential metabolites as well as labile messengers that regulate cellular physiology while traveling within and between cells. The stereospecificity of the six hydroxyls on the inositol ring provides the basis for the functional diversity of the phosphorylated isomers that, in turn, generate a selective means of intracellular and intercellular communication for coordinating cell growth. Although such complexity presents a difficult challenge for bench scientists, it is ideal for the regulation of cellular functions in living organisms.

Vaccination practices, policies, and management factors associated with high vaccination coverage levels in Georgia public clinics. Georgia Immunization Program Evaluation Team

BACKGROUND

Controlling vaccine-preventable diseases by achieving high childhood vaccination coverage levels is a national priority. However, there are few, if any, comprehensive evaluations of state immunization programs in the United States, and little attention has been given to the importance of vaccination clinic management style and staff motivation.

OBJECTIVE

To evaluate the factors associated with the increase in childhood vaccination coverage levels from 53% in 1988 to 89% in 1994 in Georgia's public health clinics.

DESIGN

A 1994 mail survey obtaining information on clinic vaccination policies and practices and management practices.

SETTING

All 227 public health clinics in Georgia.

PARTICIPANTS

Clinic nurses responsible for vaccination services.

OUTCOME MEASURE

The 1994 clinic-specific coverage level for 21- to 23-month-old children for 4 doses of diphtheria and tetanus toxoids and pertussis vaccine, 3 doses of polio vaccine, and 1 dose of a measles-containing vaccine as determined by an independent state assessment of clinic coverage levels.

RESULTS

Univariate analysis showed that higher coverage levels were significantly (P<.05) associated with smaller clinic size, higher proportions of clientele enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), being a nonurban clinic, and numerous vaccination practices and policies. Multivariable analysis showed that only 8 of greater than 150 factors remained associated with higher coverage levels, including having no waiting time to be seen, having telephone reminder systems, conducting home visits for defaulters, and restricting WIC vouchers when a child was undervaccinated. Motivational factors related to higher coverage included clinic lead nurses receiving an incentive to raise coverage and lead nurses participating in assessments of clinic coverage levels by state immunization staff.

CONCLUSIONS

No single factor is responsible for raising vaccination coverage levels. Efforts to improve coverage should include local assessment to provide feedback on performance and identify appropriate local solutions. Coordinating with WIC, conducting recall and reminder activities, motivating clinic staff, and having staff participate in decisions are important in raising vaccination levels.

The first five years: a review of the collaboration between DHHR and the WVU School of Medicine

In 1992, the West Virginia Dept. of Health and Human Resources (DHHR) and the West Virginia University School of Medicine, Dept. of Behavioral Medicine and Psychiatry (BM & P), entered into a collaborative effort to provide treatment for patients at the state-operated psychiatric hospital in Weston, W.Va. Within five years, patients were moved into a new, modern facility renamed the William R. Sharpe Jr. Hospital, which is JCAHO approved and Medicare certified; the clinical and nursing staff has increased by 38%; and students from a variety of disciplines rotate through for training. In addition, 70% of all patients admitted are discharged within 20 days or less.

A phosphatidylinositol 4-kinase pleckstrin homology domain that binds phosphatidylinositol 4-monophosphate

Pleckstrin homology (PH) domains are found in many proteins involved in signal transduction, including the family of large molecular mass phosphatidylinositol (PI) 4-kinases. Although the exact function of these newly discovered domains is unknown, it is recognized that they may influence enzyme regulation by binding different ligands. In this study, the recombinant PI 4-kinase PH domain was explored for its ability to bind to different phospholipids. First, we isolated partial cDNAs of the >7-kilobase transcripts of PI 4-kinases from carrot (DcPI4Kalpha) and Arabidopsis (AtPI4Kalpha). The deduced primary sequences were 41% identical and 68% similar to rat and human PI 4-kinases and contained the telltale lipid kinase unique domain, PH domain, and catalytic domain. Antibodies raised against the expressed lipid kinase unique, PH, and catalytic domains identified a polypeptide of 205 kDa in Arabidopsis microsomes and an F-actin-enriched fraction from carrot cells. The 205-kDa immunoaffinity-purified Arabidopsis protein had PI 4-kinase activity. We have used the expressed PH domain to characterize lipid binding properties. The recombinant PH domain selectively bound to phosphatidylinositol 4-monophosphate (PI-4-P), phosphatidylinositol 4,5-bisphosphate (PI-4,5-P2), and phosphatidic acid and did not bind to the 3-phosphoinositides. The PH domain had the highest affinity for PI-4-P, the product of the reaction. Consideration is given to the potential impact that this has on cytoskeletal organization and the PI signaling pathway in cells that have a high PI-4-P/PI-4,5-P2 ratio.

The influence of muscle fiber size and type distribution on electromyographic measures of back muscle fatigability

STUDY DESIGN

This was a cross-sectional study carried out on a group of 31 healthy, consenting volunteers with no history of low back pain (17 men, 14 women).

OBJECTIVES

To evaluate the relationship between electromyographic measures of erector spinae fatigability and the muscle's fiber type characteristics.

SUMMARY OF BACKGROUND DATA

Using electromyographic techniques, a pronounced fatigability of the muscles of patients with low back pain has been identified. It has been postulated that this is the result of an unfavorable back muscle fiber type distribution, although an association between electromyographic measures of fatigue and the muscle's fiber type characteristics has never been established.

METHODS

Two tests of back extensor fatigability were performed (on separate days), each to the limit of endurance: 1) maintenance of 60% total maximum voluntary contraction of the back extensors, and 2) performance of the Biering-Sørensen test. Pairs of surface electrodes were attached to the skin overlying the belly of the erector spinae, bilaterally, at T10 and L3. The median frequency was computed from the electromyographic power spectrum, and fatigability was given by the slope of the linear regression of median frequency on time (MFgrad; %.s-1). One week later, two percutaneous erector spinae muscle biopsy samples were obtained from the same sites described for electromyography (left side only). Samples were prepared for histochemistry for the identification of muscle fiber types. Fiber sizes (cross-sectional areas) were quantified using computerized image analysis.

RESULTS

The mean fiber size at each erector spinae region showed a significant correlation with maximum back extensor strength. In the thoracic region, the relative area of the muscle occupied by Type I fibers (which accounts for the relative size and distribution of the fiber types) showed a significant relationship with MFgrad recorded during each fatigue test. A similar relationship was observed for the lumbar region, but for the Biering-Sørensen test only.

CONCLUSIONS

The electromyographic changes recorded in back muscles during fatigue appear to be related to the underlying muscle fiber type area distribution. This confirms the usefulness of electromyography in reflecting such muscle characteristics in a noninvasive manner, when monitoring changes in function consequent to the development of, or rehabilitation from, low back pain.

Muscle fibre size and type distribution in thoracic and lumbar regions of erector spinae in healthy subjects without low back pain: normal values and sex differences

This study sought to investigate the normal muscle fibre size and type distribution of the human erector spinae, both in thoracic and lumbar regions, in a group of 31 young healthy male (n = 17) and female (n = 14) volunteers. Two percutaneous muscle biopsy samples were obtained under local anaesthesia, from the belly of the left erector spinae, at the levels of the 10th thoracic and 3rd lumbar vertebrae. Samples were prepared for routine histochemistry for the identification of fibre types. Fibre size (cross-sectional area (CSA) and narrow diameter (ND)) was quantified using computerised image analysis. The mean CSA/ND for each fibre type was greater in the thoracic than the lumbar region, but there was no difference between the 2 regions either for percentage type I (i.e. percentage distribution by number), percentage type I area (i.e. relative area of the muscle occupied by type I fibres) or the ratio describing the size of the type I fibre relative to that of the type II. Men had larger fibres than women, for each fibre type and at both sampling sites. In the men, each fibre type was of a similar mean size, whereas in the women the type I fibres were considerably larger than both the type IIA and type IIB fibres, with no difference between the latter two. In both regions of the erector spinae there was no difference between men and women for the proportion (%) of a given fibre type, but the percentage type I fibre area was significantly higher in the women. The erector spinae display muscle fibre characteristics which are clearly very different from those of other skeletal muscles, and which, with their predominance of relatively large type I (slow twitch) fibres, befit their function as postural muscles. Differences between thoracic and lumbar fascicles of the muscle, and between the muscles of men and women, may reflect adaptive responses to differences in function. In assessing the degree of any pathological change in the muscle of patients with low back pain, it seems clear that (1) sex cannot be disregarded and (2) 'atrophied' (using the criteria from other muscles) type II fibres are not necessarily abnormal for the erector spinae, particularly in women.