Variation in cardiovascular disease care: an Australian cohort study on sex differences in receipt of coronary procedures

Objectives The aim of this study was to quantify sex differences in diagnostic and revascularisation coronary procedures within 1 year of hospitalisation for acute myocardial infarction (AMI) or angina. Design This is a prospective cohort study. Baseline questionnaire (January 2006–April 2009) data from the Sax Institute’s 45 and Up Study were linked to hospitalisation and mortality data (to 30 June 2016) in a time-to-event analysis, treating death as a censoring event. Setting This was conducted in New South Wales, Australia. Participants The study included participants aged ≥45 years with no history of ischaemic heart disease (IHD) who were admitted to hospital with a primary diagnosis of AMI (n=4580) or a primary diagnosis of angina or chronic IHD with secondary diagnosis of angina (n=4457). Outcome measures The outcome of this study was coronary angiography and coronary revascularisation with percutaneous coronary intervention or coronary artery bypass graft (PCI/CABG) within 1 year of index admission. Cox regression models compared coronary procedure rates in men and women, adjusting sequentially for age, sociodemographic variables and health characteristics. Results Among patients with AMI, 71.6% of men (crude rate 3.45/person-year) and 64.7% of women (2.62/person-year) received angiography; 57.8% of men (1.73/person-year) and 37.4% of women (0.77/person-year) received PCI/CABG. Adjusted HRs for men versus women were 1.00 (0.92–1.08) for angiography and 1.51 (1.38–1.67) for PCI/CABG. In the angina group, 67.3% of men (crude rate 2.36/person-year) and 54.9% of women (1.32/person-year) received angiography; 44.6% of men (0.90/person-year) and 19.5% of women (0.26/person-year) received PCI/CABG. Adjusted HRs were 1.24 (1.14–1.34) and 2.44 (2.16–2.75), respectively. Conclusions Men are more likely than women to receive coronary procedures, particularly revascularisation. This difference is most evident among people with angina, where clinical guidelines are less prescriptive than for AMI.This research was supported by a NSW CVRN Women and Heart Disease grant from the National Heart Foundation of Australia (101692). EB is supported by the National Health and Medical Research Council of Australia (1042717

Multi-instrument observations of the effects of a solar wind pressure pulse on the high latitude ionosphere : a detailed case study of a geomagnetic sudden impulse

Funding: ARF was supported by an STFC studentship, Science Foundation Ireland Grant 18/FRL/6199, and an Irish Research Council Government of Ireland Postdoctoral Fellowship GOIPD/2022/782. ML, TKY, and SEM acknowledge support from the Science and Technology Facilities Council, UKRI, grant no. ST/W00089X/1. JAC is supported by Royal Society grant DHF\R1\211068. HKS was supported by an STFC studentship. TE was supported by a Leverhulme Trust Early Career Fellowship (ECF-2019-155), the University of Leicester and the University of Glasgow. SJW was supported by NERC studentship NE/L002493/1. MKJ was supported by STFC Grant ST/W00089X/1. JML was supported by the Irish Research Council. LJP was supported by AFOSR MURI Award 26-0201-51-62.The effects of a solar wind pressure pulse on the terrestrial magnetosphere have been observed in detail across multiple datasets. The communication of these effects into the magnetosphere is known as a positive geomagnetic sudden impulse (+SI), and are observed across latitudes and different phenomena to characterise the propagation of +SI effects through the magnetosphere. A superposition of Alfvén and compressional propagation modes are observed in magnetometer signatures, with the dominance of these signatures varying with latitude. For the first time, collocated lobe reconnection convection vortices and region 0 field aligned currents are observed preceding the +SI onset, and an enhancement of these signatures is observed as a result of +SI effects. Finally, cusp auroral emission is observed collocated with the convection and current signatures. For the first time, simultaneous observations across multiple phenomena are presented to confirm models of +SI propagation presented previously.Publisher PDFPeer reviewe

Quantification of magnetosphere–ionosphere coupling timescales using mutual information : response of terrestrial radio emissions and ionospheric–magnetospheric currents

Auroral kilometric radiation (AKR) is a terrestrial radio emission excited by the same accelerated electrons which excite auroral emissions. Although it is well correlated with auroral and geomagnetic activity, the coupling timescales between AKR and different magnetospheric or ionospheric regions have yet to be determined. Estimation of these coupling timescales is non-trivial as a result of complex, non-linear processes which rarely occur in isolation. In this study, the mutual information between AKR intensity and different geomagnetic indices is used to assess the correlation between variables. Indices are shifted to different temporal lags relative to AKR intensity, and the lag at which the variables have the most shared information is found. This lag is interpreted as the coupling timescale. The AKR source region receives the effects of a shared driver before the auroral ionosphere. Conversely, the polar ionosphere reacts to a shared driver before the AKR source region. Bow shock interplanetary magnetic field BZ is excited about 1 h before AKR enhancements. This work provides quantitatively determined temporal context to the coupling timelines at Earth. The results suggest that there is a sequence of excitation following the onset of a shared driver: first, the polar ionosphere feels the effects, followed by the AKR source region and then the auroral ionosphere

Do patients adhere to over-the-counter artemisinin combination therapy for malaria? evidence from an intervention study in Uganda

<p>Abstract</p> <p>Background</p> <p>Increasing affordability of artemisinin combination therapy (ACT) in the African retail sector could be critical to expanding access to effective malaria treatment, but must be balanced by efforts to protect the efficacy of these drugs. Previous research estimates ACT adherence rates among public sector patients, but adherence among retail sector purchasers could differ substantially. This study aimed to estimate adherence rates to subsidized, over-the-counter ACT in rural Uganda.</p> <p>Methods</p> <p>An intervention study was conducted with four licensed drug shops in Eastern Uganda in December 2009. Artemether-lumefantrine (AL) was made available for sale at a 95% subsidy over-the counter. Customers completed a brief survey at the time of purchase and then were randomly assigned to one of three study arms: no follow-up, follow-up after two days or follow-up after three days. Surveyors recorded the number of pills remaining through blister pack observation or through self-report if the pack was unavailable. The purpose of the three-day follow-up arm was to capture non-adherence in the sense of an incomplete treatment course ("under-dosing"). The purpose of the two-day follow-up arm was to capture whether participants completed the full course too soon ("over-dosing").</p> <p>Results</p> <p>Of the 106 patients in the two-day follow-up sample, 14 (13.2%) had finished the entire treatment course by the second day. Of the 152 patients in the three-day follow-up sample, 49 (32.2%) were definitely non-adherent, three (2%) were probably non-adherent and 100 (65.8%) were probably adherent. Among the 52 who were non-adherent, 31 (59.6%) had more than a full day of treatment remaining.</p> <p>Conclusions</p> <p>Overall, adherence to subsidized ACT purchased over-the-counter was found to be moderate. Further, a non-trivial fraction of those who complete treatment are taking the full course too quickly. Strategies to increase adherence in the retail sector are needed in the context of increasing availability and affordability of ACT in this sector.</p

SuperDARN Heppner-Maynard Boundaries

SuperDARN Heppner-Maynard Boundary latitudes for the Northern Hemisphere for 2011 and 2015. Determined using the traditional latitude determination condition and all available high and polar latitude radar data. Data files provide date, time and the midnight meridian value of the Heppner-Maynard Boundary

SuperDARN Observations of High Latitude Electrodynamics in the Terrestrial Ionosphere

Coupling of the solar wind and interplanetary magnetic field to the terrestrialsystem results in a dynamic magnetosphere-ionosphere interaction, full of complexityyet to be unravelled. In this thesis, high latitude electrodynamics willbe examined in relation to solar wind - magnetosphere - ionosphere coupling,primarily by observations from the Super Dual Auroral Radar Network (Super-DARN). SuperDARN is made up of, at time of writing, over 35 high frequencycoherent scatter radars, which provide near global coverage of the geomagneticpoles. Originally conceived to measure ionospheric convection, the SuperDARNdataset can be assimilated into minute resolution electrostatic potential solutions,known as ionospheric convection maps, which are the primary diagnostic tool inthis thesis. The quality of the derived equipotential maps is dependent on a varietyof processing stages, including the determination of the low latitude limitof the convection pattern. Firstly, a new method for determining the position ofthis boundary is presented, based on an examination of the relationship betweenthe scale sizes of the convection and field aligned current (FAC) regions. A linearrelationship is demonstrated, which can be used, incorporating independent FACmeasurements, to estimate a scatter independent measure of the low latitudelimit of the convection region. Finally, the effects of the impact of solar windpressure pulses on the terrestrial ionosphere will be examined. If the pressurepulse compresses the magnetosphere but does not trigger a geomagnetic storm,this is known as a positive sudden impulse. Enhancements in dayside driving ofthe ionosphere following the onset of a positive sudden impulse will be presentedboth in the form of a detailed case study, and statistically using a superposedepoch analysis. For the first time, simultaneous measurements of ionosphericconvection and FACs will be utilised to observe the effects of this phenomenon.</div

Solar Wind control of Auroral Kilometric Radiation as measured by the Wind Satellite

International audienc

A perspective on substorm dynamics from 10 years of Auroral Kilometric Radiation

International audienceAuroral Kilometric Radiation (AKR) is terrestrial radio emission that originates from high latitude magnetic field lines. The intensity of AKR increases when the magnetosphere is perturbed, and so can indicate the presence of driving from the solar wind. This is true for structures that can vary in scale such as pressure pulses, as well as substorm onsets that follow periods of negative turnings in the Z component of the interplanetary magnetic field. In the latter case, AKR intensification correlates with the strengthening of high-latitude current systems in the ionosphere as the magnetotail current is reconfigured. As well as this, morphological changes in the AKR source region have also been observed to coincide with substorm onset, with an intensification of the AKR emission often accompanied by a low frequency extension, interpreted as an expansion of the source region to higher altitudes along the field line. Although the directivity and source region localisation of AKR make the observations highly dependent on observer local time and latitude, we isolate AKR from Wind radio observations made over a decade and examine the observations with respect to the spacecraft viewing position, accounting for such effects. Using lists of substorm onsets, we examine the AKR power and the spectral extent of the emission with respect to the substorm timeline, expanding on previous studies of the AKR response. Results show a clear increase in AKR power that precedes substorm onset by approximately 20 minutes, and confirm a proportionally higher intensification in lower frequency AKR sources. This in turn indicates quantitatively the spatial response of parallel electric fields after the loading of magnetic flux during substorm growth phase. In characterising the typical AKR response during substorms, these results can inform observations of magnetospheric changes during sudden commencement events and those that are seperate from substorm dynamics