Definition of Polypharmacy in Heart Failure: A Scoping Review of the Literature

Patients with heart failure (HF) have a high prevalence of polypharmacy, which can lead to drug interactions, cognitive impairment, and medication non-compliance. However, the definition of polypharmacy in these patients is still inconsistent. The aim of this scoping review was to find the most common definition of polypharmacy in HF patients. We conducted a scoping review searching Medline, Embase, CINAHL, and Cochrane using terms including polypharmacy, HF and deprescribing, which resulted in 7,949 articles. Articles without a definition of polypharmacy in HF patients and articles which included patients < 18 years of age were excluded; only 59 articles were included. Of the 59 articles, 49% (n = 29) were retrospective, 20% (n = 12) were prospective, 10% (n = 6) were cross-sectional, and 27% (n = 16) were review articles. Twenty percent (n = 12) of the articles focused on HF with reduced ejection fraction, 10% (n = 6) focused on HF with preserved ejection fraction and 69% (n = 41) articles either focused on both diagnoses or did not clarify the specific type of HF. The most common cutoff for polypharmacy in HF was five medications (59%, n = 35). There was no consensus regarding the inclusion or exclusion of over-the-counter medications, supplements, or vitamins. Some newer studies used a cutoff of 10 medications (14%, n = 8), and this may be a more practical and meaningful definition for HF patients.

How do we define high and low dose intensity of heart failure medications: a scoping review

BACKGROUND

Older adults with heart failure often experience adverse drug events with high doses of heart failure medications. Recognizing whether a patient is on a high or low dose intensity heart failure medication can be helpful for daily practice, since it could potentially guide the physician on which symptoms to look for, whether from overdosing or underdosing. However, the current guideline does not provide sufficient information about the dose intensity below the target dose. Furthermore, the definition of high or low-intensity heart failure medication is unclear, and there is no consensus.

METHODS

To close the knowledge gap, we conducted a scoping review of the current literature to identify the most frequently used definition of high versus low doses of heart failure medications. We searched Pubmed, Embase, CINAHL, and Cochrane Library using comprehensive search terms that can capture the intensity of heart failure medications.

RESULTS

We reviewed 464 articles, including 144 articles that had information about beta-blockers (BB), 179 articles about angiotensin-converting enzyme inhibitors (ACEi), 75 articles about angiotensin receptor blockers (ARB), 80 articles about diuretics, 37 articles about mineralocorticoid receptor antagonists (MRA), and 33 articles about angiotensin receptor-neprilysin inhibitor (ARNI). For hydralazine with isosorbide dinitrate or ivabradine, we could not identify any eligible articles. We identified 40 medications with most frequently used definitions of dose intensity. Four medications (nadolol, pindolol, cilazapril, and torsemide) did not reach consensus in definitions. Most of the BBs, ACEis, or ARBs used the definition of low being < 50% of the target dose and high being ≥ 50% of the target dose from the guideline. However, for lisinopril and losartan, the most commonly used definitions of high or low were from pivotal clinical trials with a pre-defined definition of high or low.

CONCLUSION

Our comprehensive scoping review studies identified the most frequently used definition of dose intensity for 40 medications but could not identify the definitions for 4 medications. The results of the current scoping review will be helpful for clinicians to have awareness whether the currently prescribed dose is considered high - requiring close monitoring of side effects, or low - requiring more aggressive up-titration.

A scoping review of randomized trials assessing the impact of n-of-1 trials on clinical outcomes

BACKGROUND

The single patient (n-of-1) trial can be used to resolve therapeutic uncertainty for the individual patient. Treatment alternatives are systematically tested against each other, generating patient-specific data used to inform an individualized treatment plan. We hypothesize that clinical decisions informed by n-of-1 trials improve patient outcomes compared to usual care. Our objective was to provide an overview of the clinical trial evidence on the effect of n-of-1 trials on clinical outcomes.

METHODS

A systematic search of medical databases, trial registries, and gray literature was performed to identify trials assessing clinical outcomes in a group of patients undergoing an n-of-1 trial compared to those receiving usual care for any clinical condition. We abstracted elements related to study design and results and assessed risk of bias for both the overall randomized trials and the n-of-1 trials. The review was registered on PROSPERO. (CRD: 42020166490).

FINDINGS

Twelve randomized trials of the n-of-1 approach were identified in conditions spanning chronic pain, osteoarthritis, chronic irreversible airflow limitation, attention-deficit hyperactivity disorder, hyperlipidemia, atrial fibrillation, statin intolerance, and hypertension. One trial showed a statistically significant benefit in the primary outcome. Only one reached the pre-specified sample size target. Secondary outcomes showed modest benefits, including decreasing medication use, fewer atrial fibrillation episodes, and improved patient satisfaction.

INTERPRETATION

Very few trials have been undertaken to assess the effectiveness of n-of-1 trials in improving clinical outcomes, and most trials were underpowered for the primary outcome. Barriers to enrollment and retention in these trials should be explored, as well-powered randomized trials are needed to clarify the clinical impact of n-of-1 trials and assess their utility in clinical practice.

Long-range nontopological edge currents in charge-neutral graphene

Van der Waals heterostructures display numerous unique electronic properties. Nonlocal measurements, wherein a voltage is measured at contacts placed far away from the expected classical flow of charge carriers, have been widely used in the search for novel transport mechanisms, including dissipationless spin and valley transport^1-9, topological charge-neutral currents^10-12, hydrodynamic flows¹³ and helical edge modes^14-16. Monolayer^1-5,10,15-19, bilayer^9,11,14,20 and few-layer²¹ graphene, transition-metal dichalcogenides^6,7 and moiré superlattices^8,10,12 have been found to display pronounced nonlocal effects. However, the origin of these effects is hotly debated^{3,11,17,22-24}. Graphene, in particular, exhibits giant nonlocality at charge neutrality^1,15-19, a striking behaviour that has attracted competing explanations. Using a superconducting quantum interference device on a tip (SQUID-on-tip) for nanoscale thermal and scanning gate imaging²⁵, here we demonstrate that the commonly occurring charge accumulation at graphene edges^23,26-31 leads to giant nonlocality, producing narrow conductive channels that support long-range currents. Unexpectedly, although the edge conductance has little effect on the current flow in zero magnetic field, it leads to field-induced decoupling between edge and bulk transport at moderate fields. The resulting giant nonlocality at charge neutrality and away from it produces exotic flow patterns that are sensitive to edge disorder, in which charges can flow against the global electric field. The observed one-dimensional edge transport is generic and nontopological and is expected to support nonlocal transport in many electronic systems, offering insight into the numerous controversies and linking them to long-range guided electronic states at system edges.

A meta-analysis of the global impact of the COVID-19 pandemic on stroke care & the Houston Experience

OBJECTIVE

To review the global impact of the COVID-19 pandemic on stroke care-metrics and report data from a health system in Houston.

METHODS

We performed a meta-analysis of the published literature reporting stroke admissions, intracerebral hemorrhage (ICH) cases, number of thrombolysis (tPA) and thrombectomy (MT) cases, and time metrics (door to needle, DTN; and door to groin time, DTG) during the pandemic compared to prepandemic period. Within our hospital system, between January-June 2019 and January-June 2020, we compared the proportion of stroke admissions and door to tPA and MT times.

RESULTS

A total of 32,640 stroke admissions from 29 studies were assessed. Compared to prepandemic period, the mean ratio of stroke admissions during the pandemic was 70.78% [95% CI, 65.02%, 76.54%], ICH cases was 83.10% [95% CI, 71.01%, 95.17%], tPA cases was 81.74% [95% CI, 72.33%, 91.16%], and MT cases was 88.63% [95% CI, 74.12%, 103.13%], whereas DTN time was 104.48% [95% CI, 95.52%, 113.44%] and DTG was 104.30% [95% CI, 81.99%, 126.61%]. In Houston, a total of 4808 cases were assessed. There was an initial drop of ~30% in cases at the pandemic onset. Compared to 2019, there was a significant reduction in mild strokes (NIHSS 1-5) [N (%), 891 (43) vs 635 (40), P = 0.02]. There were similar mean (SD) (mins) DTN [44 (17) vs 42 (17), P = 0.14] but significantly prolonged DTG times [94 (15) vs 85 (20), P = 0.005] in 2020.

INTERPRETATION

The COVID-19 pandemic led to a global reduction in stroke admissions and treatment interventions and prolonged treatment time metrics.

N-of-1 Trials as a Decision Support Tool in Clinical Practice: A Protocol for a Systematic Literature Review and Narrative Synthesis

The n-of-1 trial can utilized in clinical practice as a decision support tool, which may improve patient outcomes by providing both the patient and the clinician with objective evidence to inform personalized treatment decisions. As its use broadens, it will be important to study whether the added time and effort of an n-of-1 trial results in measurable improvements in important patient outcomes compared to usual clinical practice. Parallel-group randomized clinical trials testing the n-of-1 approach versus usual care have been undertaken in a number of medical settings. A systematic review will be performed according to PRISMA guidelines, using MEDLINE, Embase, Cochrane, CINAHL, PsycINFO, Scopus, and Web of Science to search for randomized clinical trials in humans, without date or language restriction. Reports from the gray literature and ongoing studies in trial registries will be included. Articles will be screened by two independent reviewers with a third reviewer consulted to adjudicate disagreement. The quality of included studies will be assessed using the Cochrane Collaboration's tool for assessing risk of bias. A narrative synthesis will explore the differing methodological approaches of the included studies. The protocol will be registered in the PROSPERO registry, and the results of the review will be published in a peer-reviewed journal. To our knowledge, this systematic review will be the first to comprehensively assess the existing research on randomized trials testing the n-of-1 trial approach in clinical practice.

Supra-maximal effort and reaction and movement times in a non-compatible response time task

AIM

The primary purpose of this study was to examine the effect of attempting to exercise supra-maximally on reaction time and movement time in a non-compatible response time task.

METHODS

Subjects (n=9) undertook a 4-choice non-compatible response time test at rest, while cycling at 70 rpm with a resistance of 35 W (low intensity exercise), cycling at 70% of their maximum power output (MPO), cycling at 100% MPO and attempting to cycle at 70 rpm, with a resistance that was 28 W greater than the resistance required to elicit MPO (supra-maximal effort).

RESULTS

Reaction time, movement time, intra-individual variations in reaction time and movement time at each exercise intensity were compared by a series of repeated measures analyses of variance. A significant effect of exercise was shown for movement time, F(4,32)=6.05, p<0.001, eta2=0.44, Power=0.97 and intra-individual variation in reaction time, F(4,32)=4.98, p<0.005, eta2=0.38, Power=0.93. For movement time, Tukey post-hoc tests showed that performance at rest was significantly slower than that during exercise at 70%, 100% MPO and supra-maximal effort. Performance at low intensity exercise was significantly slower than that at MPO. For intra-individual variations in reaction time, Tukey tests found that variations under supra-maximal effort and MPO were significantly greater than those at low intensity and 70% MPO.

CONCLUSIONS

It was concluded that exercise facilitates speed of movement when the limbs used for the motor task are not the ones that are being exercised. Reaction time during maximal and supra-maximal exercise demonstrates large intra-individual variations.

Quantification of groundwater contamination in an urban area using integral pumping tests

In this paper, the integral groundwater investigation method is used for the quantification of PCE and TCE mass flow rates at an industrialized urban area in Linz, Austria. In this approach, pumping wells positioned along control planes perpendicular to the groundwater flow direction are operated for a time period on the order of days and sampled for contaminants. The concentration time series of the contaminants measured during operation of the pumping wells are then used to determine contaminant mass flow rates, mean concentrations and the plume shapes and positions at the control planes. The three control planes used in Linz were positioned downstream of a number of potential source zones, which are distributed over the field site. By use of the integral investigation method, it was possible to identify active contaminant sources, quantify the individual source strength in terms of mass flow rates at the control planes and estimate the contaminant plume position relative to the control planes. The source zones emitting the highest PCE and TCE mass flow rates could be determined, representing the areas where additional investigation and remediation activities will be needed. Additionally, large parts of the area investigated could be excluded from further investigation and remediation activities.

Functional dynamics in the active site of the ribonuclease binase

Binase, a member of a family of microbial guanyl-specific ribonucleases, catalyzes the endonucleotic cleavage of single-stranded RNA. It shares 82% amino acid identity with the well-studied protein barnase. We used NMR spectroscopy to study the millisecond dynamics of this small enzyme, using several methods including the measurement of residual dipolar couplings in solution. Our data show that the active site of binase is flanked by loops that are flexible at the 300-micros time scale. One of the catalytic residues, His-101, is located on such a flexible loop. In contrast, the other catalytic residue, Glu-72, is located on a beta-sheet, and is static. The residues Phe-55, part of the guanine base recognition site, and Tyr-102, stabilizing the base, are the most dynamic. Our findings suggest that binase possesses an active site that has a well-defined bottom, but which has sides that are flexible to facilitate substrate access/egress, and to deliver one of the catalytic residues. The motion in these loops does not change on complexation with the inhibitor d(CGAG) and compares well with the maximum k(cat) (1,500 s(-1)) of these ribonucleases. This observation indicates that the NMR-measured loop motions reflect the opening necessary for product release, which is apparently rate limiting for the overall turnover.

Education on health risks of smoking in Magadan, Russia

PURPOSE

The purpose of this project was to educate young Russians on the health risks of smoking.

METHOD

The American Cancer Society, Alaska Division, sponsored a project to deliver its teaching modules on the health risks of tobacco use to first- through third-graders in Magadan, Russia. Starting with a $4,400 (U.S.) contribution designated for this purpose, a young teacher, Irina Alishova, was contacted in Magadan in 1993. She translated the modules of the American Cancer Society oriented to the first- to the third-grade level. Irina also made contact with the Magadan school system, specifically the principal of Middle School Number 29, Alla Vakulyuk. Principal Vakulyuk encouraged the project and worked with the other schools in the Magadan school system.

RESULTS

Throughout the 1993-94 school year, nearly all of the first- and second-grade classes and a portion of the third-grade classes received and participated in the 50-minute teaching module. An American representative for the American Cancer Society observed one of the classes and noted thoughtful and enthusiastic participation by the schoolchildren.