Is the incidence of heart attack still decreasing in Australia? Developing reliable methods for monitoring trends in myocardial infarction and coronary heart disease (AUS-MOCHA): a study protocol

INTRODUCTION

Accurate monitoring of acute coronary heart disease (CHD) is essential for understanding the effects of primary and secondary prevention and for planning of healthcare services. The ability to reliably monitor acute CHD has been affected by new diagnostic tests for myocardial infarction (MI) and changing clinical classifications and management of CHD. Our study will develop new and reliable methods for monitoring population trends in incidence, outcomes and health service usage for acute CHD and chest pain.

METHODS AND ANALYSIS

The study cohort of all CHD will be identified from the Western Australian Data Linkage System using state-wide data sets for emergency department presentation, hospitalisations and mortality data for 2002-2014. This core linked data set will be supplemented with data from hospital medical record reviews, pathology data and hospital pharmacy dispensing databases. The consistency over time of the coding of the different subgroups of CHD/chest pain (ST-elevation MI, non-ST elevation MI, unstable angina, stable angina, other CHD, non-CHD chest pain) in linked data will be assessed using these data sources, and an algorithm developed detailing groups in which temporal trends can be reliably measured. This algorithm will be used for measurement of trends in incidence and outcomes of acute CHD, and to develop further methods for monitoring acute CHD using unlinked and linked data with varying availability of hospitalisation history.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the Human Research Ethics Committees of the WA Department of Health (#2016/23) and The University of Western Australia (RA/4/1/7230). Findings will be disseminated via publication in peer-reviewed journals, and presentation at national and international conferences. There will also be a strong platform for dissemination of new monitoring methods via collaboration with the Australian Institute of Health and Welfare which will assist with promotion of these methods at state and national levels.

Impact of thrombolysis in acute ischaemic stroke without occlusion: an observational comparative study

BACKGROUND AND PURPOSE

The impact of intravenous recombinant tissue plasminogen activator (IV-rtPA) in patients with acute ischaemic stroke (AIS) but no arterial occlusion is currently a matter of debate. This study aimed to assess functional outcome of such patients with respect to IV-rtPA use.

METHODS

A retrospective case-control analysis was performed comparing the outcome of AIS patients without arterial occlusion with or without IV-rtPA use. Patients were selected from prospective consecutive observational registries of five European university hospitals. The primary study outcome was excellent outcome at 3 months after stroke, as defined by a modified Rankin Scale (mRS) 0-1.

RESULTS

A total of 488 patients without arterial occlusion documented by angiography were included in the present study; 300 received IV-rtPA and 188 did not. No between-group difference was found for excellent outcome before and after adjustment for baseline characteristics (adjusted odds ratio for no IV-rtPA use 0.79, 95% confidence interval 0.51-1.24, P = 0.31). Similar results were found for favourable outcome (defined as a 90-day mRS of 0-2) whereas a higher rate of early neurological improvement was found in IV-rtPA-treated patients (adjusted odds ratio 1.99; 95% confidence interval 1.29-3.07, P = 0.002). Sensitivity analyses yielded similar results.

CONCLUSIONS

Our study suggests that AIS patients without visible arterial occlusion treated with IV-rtPA may have no better outcome at 3 months than those untreated. However, only a randomized controlled trial would provide a definitive answer about the impact of rtPA in acute stroke patients without occlusion. Until then, these patients should be treated by rtPA as recommended.

Application of transit data analysis and artificial neural network in the prediction of discharge of Lor River, NW Spain

Transit data analysis and artificial neural networks (ANNs) have proven to be a useful tool for characterizing and modelling non-linear hydrological processes. In this paper, these methods have been used to characterize and to predict the discharge of Lor River (North Western Spain), 1, 2 and 3 days ahead. Transit data analyses show a coefficient of correlation of 0.53 for a lag between precipitation and discharge of 1 day. On the other hand, temperature and discharge has a negative coefficient of correlation (-0.43) for a delay of 19 days. The ANNs developed provide a good result for the validation period, with R(2) between 0.92 and 0.80. Furthermore, these prediction models have been tested with discharge data from a period 16 years later. Results of this testing period also show a good correlation, with R(2) between 0.91 and 0.64. Overall, results indicate that ANNs are a good tool to predict river discharge with a small number of input variables.

Development of the National Kidney Transplantation Program in Uruguay

The first kidney transplantation (KT) in Uruguay was performed in 1969. We report the rates of KT and survival of patients and grafts up to December 2014. The country has a surface of 176,215 km(2) and a population of 3,286,314 inhabitants (18.6 inhabitants per km(2)). Till December 31, 2014, 1,940 KT have been performed in Uruguay (41.8 pmp that year); 90.4% of them were from cadaveric donors (CD). Median age of recipients (R) was 44 ± 14 years; R older than 55 years increased from 0 to 27% during the period. Our pre-emptive KT program started in 2007. Optimal donors (D) decreased from 65.2% to 35.5%, and D older than 45 years old increased from 9% to 37%. Trauma as cause of death decreased from 49% to 32% and stroke as cause of death increased from 25% to 39%. Patient survival rates at 1, 5, and 8 years were 93%, 87%, and 78%, respectively for KT performed between 1980 and 1989; they were 98%, 93%, and 89%, respectively, for KT performed between 1990 and1999; they were 97%, 91%, and 90%, respectively, for KT performed between 2000 and 2010. In December 2013, there were 1098 patients pmp in renal replacement therapy, 758 pmp in dialysis, and 340 pmp (30.9%) with a functioning graft. Our national KT program is mainly based (90.6%) on cadaveric donation. Epidemiological changes in the characteristics of R and D followed the changes in aging that occurred in the general population and the dialysis population. The survival rates from patients and kidneys are similar to those reported by the European and the American registries.

Calcium phosphate supplementation increases faecal Lactobacillus spp. in a randomised trial of young adults

The aim of the studies was to determine the effects of calcium carbonate and calcium phosphate supplementation on faecal Lactobacillus spp., with and without a probiotic supplement, in healthy adults. Study 1 comprised of a randomised, double-blind, crossover design; participants (n=15) received 2 capsules/d of 250 mg elemental calcium as calcium carbonate (Ca1) and calcium phosphate (Ca2) each for 2-week periods, with 2-week baseline and washout periods. Study 2 was a randomised, double-blind, crossover design; participants (n=17) received 2 capsules/d of Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011 (probiotic) alone, the probiotic with 2 capsules/d of Ca1, and probiotic with 2 capsules/d of Ca2 each for 2-week periods with 2-week baseline and washout periods. In both studies, stools were collected during the baseline, intervention and washout periods for Lactobacillus spp. quantification and qPCR analyses. Participants completed daily questionnaires of stool frequency and compliance. In Study 1, neither calcium supplement influenced viable counts of resident Lactobacillus spp., genome equivalents of lactic acid bacteria or stool frequency. In Study 2, faecal Lactobacillus spp. counts were significantly enhanced from baseline when the probiotic was administered with Ca2 (4.83±0.30, 5.79±0.31) (P=0.02), but not with Ca1 (4.98±0.31) or with the probiotic alone (5.36±0.31, 5.55±0.29) (not significant). Detection of L. helveticus R0052 and L. rhamnosus R0011 was significantly increased with all treatments, but did not differ among treatments. There were no changes in weekly stool frequency. Calcium phosphate co-administration may increase gastrointestinal survival of orally-administered Lactobacillus spp.

The epidemiology of reoperations for orthopaedic trauma

INTRODUCTION

The Royal College of Surgeons of England (RCS) has issued guidance regarding the use of reoperation rates in the revalidation of UK-based orthopaedic surgeons. Currently, little has been published concerning acceptable rates of reoperation following primary surgical management of orthopaedic trauma, particularly with reference to revalidation.

METHODS

A retrospective review was conducted of patients undergoing clearly defined reoperations following primary surgical management of trauma between 1 January 2010 and 31 December 2011. A full case note review was undertaken to establish the demographics, clinical course and context of reoperation. A review of the imaging was performed to establish whether the procedure performed was in line with accepted trauma practice and whether the technical execution was acceptable.

RESULTS

A total of 3,688 patients underwent primary procedures within the time period studied while 70 (1.90%, 99% CI: 1.39-2.55) required an unplanned reoperation. Thirty-nine (56%) of these patients were male. The mean age of patients was 56 years (range: 18-98 years) and there was a median time to reoperation of 50 days (IQR: 13-154 days). Potentially avoidable reoperations occurred in 41 patients (58.6%, 99% CI: 43.2-72.6). This was largely due to technical errors (40 patients, 57.1%, 99% CI: 41.8-71.3), representing 1.11% (99% CI: 0.73-1.64) of the total trauma workload. Within RCS guidelines, 28-day reoperation rates for hip, wrist and ankle fractures were 1.4% (99% CI: 0.5-3.3), 3.5% (99% CI: 0.8%-12.1) and 1.86% (99% CI: 0.4-6.6) respectively.

CONCLUSIONS

We present novel work that has established baseline reoperation rates for index procedures required for revalidation of orthopaedic surgeons.

Disparities experienced by Aboriginal compared to non-Aboriginal metropolitan Western Australians in receiving coronary angiography following acute ischaemic heart disease: the impact of age and comorbidities

INTRODUCTION

Aboriginal Australians have a substantially higher frequency of ischaemic heart disease (IHD) events than their non-Aboriginal counterparts, together with a higher prevalence of comorbidities. The pattern of health service provision for IHD suggests inequitable delivery of important diagnostic procedures. Published data on disparities in IHD management among Aboriginal Australians are conflicting, and the role of comorbidities has not been adequately delineated. We compared the profiles of Aboriginal and non-Aboriginal patients in the metropolitan area undergoing emergency IHD admissions at Western Australian metropolitan hospitals, and investigated the determinants of receiving coronary angiography.

METHODS

Person-linked administrative hospital and mortality records were used to identify 28-day survivors of IHD emergency admission events (n =20,816) commencing at metropolitan hospitals in 2005-09. The outcome measure was receipt of angiography. The Aboriginal to non-Aboriginal risk ratio (RR) was estimated from a multivariable Poisson log-linear regression model with allowance for multiple IHD events in individuals. The subgroup of myocardial infarction (MI) events was modelled separately.

RESULTS

Compared with their non-Aboriginal counterparts, Aboriginal IHD patients were younger and more likely to have comorbidities. In the age- and sex-adjusted model, Aboriginal patients were less likely than others to receive angiography (RRIHD 0.77, 95% CI 0.72-0.83; RRMI 0.81, 95% CI 0.75-0.87) but in the full multivariable model this disparity was accounted for by comorbidities as well as IHD category and MI subtype, and private health insurance (RRIHD 0.95, 95% CI 0.89-1.01; RRMI 0.94, 95% CI 0.88-1.01). When stratified by age groups, this disparity was not significant in the 25-54 year age group (RRMI 0.95, 95% CI 0.88-1.02) but was significant in the 55-84 year age group (RRMI 0.88, 95% CI 0.77-0.99).

CONCLUSIONS

The disproportionate under-management of older Aboriginal IHD patients is of particular concern. Regardless of age, the disparity between Aboriginal and non-Aboriginal Australians in receiving angiography for acute IHD in a metropolitan setting is mediated substantially by comorbidities. This constellation of health problems is a 'double-whammy' for Aboriginal people, predisposing them to IHD and also adversely impacting on their receipt of angiography. Further research should investigate how older age and comorbidities influence clinical decision making in this context.

Long-term use and cost-effectiveness of secondary prevention drugs for heart disease in Western Australian seniors (WAMACH): a study protocol

INTRODUCTION

Secondary prevention drugs for cardiac disease have been demonstrated by clinical trials to be effective in reducing future cardiovascular and mortality events (WAMACH is the Western Australian Medication Adherence and Costs in Heart disease study). Hence, most countries have adopted health policies and guidelines for the use of these drugs, and included them in government subsidised drug lists to encourage their use. However, suboptimal prescribing and non-adherence to these drugs remains a universal problem. Our study will investigate trends in dispensing patterns of drugs for secondary prevention of cardiovascular events and will also identify factors influencing these patterns. It will also assess the clinical and economic consequences of non-adherence and the cost-effectiveness of using these drugs.

METHODS AND ANALYSIS

This population-based cohort study will use longitudinal data on almost 40,000 people aged 65 years or older who were hospitalised in Western Australia between 2003 and 2008 for coronary heart disease, heart failure or atrial fibrillation. Linking of several State and Federal government administrative data sets will provide person-based information on drugs dispensed precardiac and postcardiac event, reasons for hospital admission, emergency department visits, mortality and medical visits. Dispensed drug trends will be described, drug adherence measured and their association with future all-cause/cardiovascular events will be estimated. The cost-effectiveness of these long-term therapies for cardiac disease and the impact of adherence will be evaluated.

ETHICS AND DISSEMINATION

Human Research Ethics Committee (HREC) approvals have been obtained from the Department of Health (Western Australian #2011/62 and Federal) and the University of Western Australia (RA/4/1/1130), in addition to HREC approvals from all participating hospitals. Findings will be published in peer-reviewed medical journals and presented at local, national and international conferences. Results will also be disseminated to consumer groups.

Radon as a natural tracer for gas transport within uranium waste rock piles

Acid mine drainage (AMD) has been identified as the main cause for outflow of acid water and radioactive/non-radioactive contaminants. AMD encompasses pyrites oxidation when water and oxygen are available. AMD was identified in uranium waste rock piles (WRPs) of Indústrias Nucleares do Brasil-Caldas facility (Brazilian uranium mine), resulting in high costs for water treatment. AMD reduction is the main challenge, and scientific investigation has been conducted to understand oxygen and water transportation within WRPs, where 222Rn is used as natural tracer for oxygen transportation. The study consists of soil radon gas mapping in the top layer of WRP4 using active soil gas pumping, radon adsorption in active charcoal and 222Rn determination using high-resolution gamma-ray spectrometry. A sampling network of 71 points was built where samples were collected at a depth of 40 cm. Soil radon gas concentration ranged from 33.7 to 1484.2 kBq m(-3) with mean concentration of 320.7±263.3 kBq m(-3).

Transfers to metropolitan hospitals and coronary angiography for rural Aboriginal and non-Aboriginal patients with acute ischaemic heart disease in Western Australia

Background

Aboriginal people have a disproportionately higher incidence rate of ischaemic heart disease (IHD) than non-Aboriginal people. The findings on Aboriginal disparity in receiving coronary artery procedures are inconclusive. We describe the profile and transfers of IHD patients admitted to rural hospitals as emergency admissions and investigate determinants of transfers and coronary angiography.

Methods

Person-linked hospital and mortality records were used to identify 28-day survivors of IHD events commencing at rural hospitals in Western Australia. Outcome measures were receipt of coronary angiography, transfer to a metropolitan hospital, and coronary angiography if transferred to a metropolitan hospital.

Results

Compared to non-Aboriginal patients, Aboriginal patients with IHD were more likely to be younger, have more co-morbidities, reside remotely, but less likely to have private insurance. After adjusting for demographic characteristics, Aboriginal people with MI were less likely to be transferred to a metropolitan hospital, and if transferred were less likely to receive coronary angiography. These disparities were not significant after adjusting for comorbidities and private insurance. In the full multivariate model age, comorbidities and private insurance were adversely associated with transfer to a metropolitan hospital and coronary angiography.

Conclusion

Disparity in receiving coronary angiography following emergency admission for IHD to rural hospitals is mediated through the lower likelihood of being transferred to metropolitan hospitals where this procedure is performed. The likelihood of a transfer is increased if the patient has private insurance, however, rural Aboriginal people have a lower rate of private insurance than their non-Aboriginal counterparts. Health practitioners and policy makers can continue to claim that they treat Aboriginal and non-Aboriginal people alike based upon clinical indications, as private insurance is acting as a filter to reduce rural residents accessing interventional cardiology. If health practitioners and policy makers are truly committed to reducing health disparities, they must reflect upon the broader systems in which disparity is perpetuated and work towards a systems improvement.

Progression to insulin for patients with diabetes mellitus on dual oral antidiabetic therapy using the US Department of Defense Database

AIM

To compare 'progression to insulin' for three cohorts on oral antidiabetic medication combinations: metformin/sulphonylurea (Met/SU), metformin/thiazolidinedione (Met/TZD) and sulphonylurea/thiazolidinedione (SU/TZD).

METHODS

Retrospective cohort analysis design was used. The subjects were US nationwide members of military and their families. A total of 5608 patients who were on antidiabetic monotherapy for at least 1 year before adding a second agent to their medication regimen between October 2001 and September 2008 participated in this study. Mean age ranged from 64 to 71 years among the cohorts. Cox regression compared the progression to insulin, adjusting for demographics, months of follow-up and co-morbidities [measured with Chronic Disease Score (CDS)].

RESULTS

By the end of the 2- to 6-year follow-up period, 14.3% of the Met/TZD cohort, 23.6% of the Met/SU cohort and 28.2% of the SU/TZD cohort had insulin added to their regimen. Those in the Met/SU cohort had a 1.8 times higher probability of progression to insulin than those in the Met/TZD cohort [odds ratio (OR) = 1.80, 95% confidence interval (CI) = 1.51-2.14), and those in the SU/TZD cohort had a 2.5 times higher probability of progression to insulin than those in the Met/TZD cohort (OR = 2.51, 95% CI = 2.04-3.08).

CONCLUSION

When sensitizers were paired (Met/TZD), a lower percentage of patients progressed to insulin during the study period, as opposed to patients who used a combination of a secretagogue with a sensitizer (SU/TZD or Met/SU).

Should we continue temozolomide beyond six cycles in the adjuvant treatment of glioblastoma without an evidence of clinical benefit? A cost analysis based on prescribing patterns in Spain

PURPOSE

The standard adjuvant treatment for glioblastoma is temozolomide concomitant with radiotherapy, followed by a further six cycles of temozolomide. However, due to the lack of empirical evidence and international consensus regarding the optimal duration of temozolomide treatment, it is often extended to 12 or more cycles, even in the absence of residual disease. No clinical trial has shown clear evidence of clinical benefit of this extended treatment. We have explored the economic impact of this practice in Spain.

MATERIALS AND METHODS

Spanish neuro-oncologists completed a questionnaire on the clinical management of glioblastomas in their centers. Based on their responses and on available clinical and demographic data, we estimated the number of patients who receive more than six cycles of temozolomide and calculated the cost of this extended treatment.

RESULTS

Temozolomide treatment is continued for more than six cycles by 80.5 % of neuro-oncologists: 44.4 % only if there is residual disease; 27.8 % for 12 cycles even in the absence of residual disease; and 8.3 % until progression. Thus, 292 patients annually will continue treatment beyond six cycles in spite of a lack of clear evidence of clinical benefit. Temozolomide is covered by the National Health Insurance System, and the additional economic burden to society of this extended treatment is nearly 1.5 million euros a year.

CONCLUSIONS

The optimal duration of adjuvant temozolomide treatment merits investigation in a clinical trial due to the economic consequences of prolonged treatment without evidence of greater patient benefit.