Complex impact of remoteness on the incidence of myocardial infarction in Aboriginal and non-Aboriginal people in Western Australia

Trends in Ischaemic Heart Disease in Australia, 2001-2015: A Comparison of Urban and Rural Populations

OBJECTIVE

Ischaemic heart disease (IHD) is a major source of disease burden worldwide. Recent trends show incidence is declining but it is unclear whether the trends are similar in urban and rural populations. This study examines the trends of IHD events (i.e. hospitalisations and deaths) in New South Wales, Australia by rurality.

METHODS

This was a retrospective analysis of linked administrative data for hospitalisation and death records across NSW between 2001 and 2015. Participants were NSW residents aged 15-105 years who died or were hospitalised with a principal diagnosis of IHD. The main outcome measures were annual age-standardised mortality and hospitalisations for IHD by calendar year and rurality.

RESULTS

Between 2001 and 2015, age-standardised annual IHD hospitalisations declined in urban areas from 587 to 260 and in rural areas from 766 to 395 per 100,000 people. The annual decline in hospitalisations was greater in urban than rural areas, with Annual Percentage Change (APC) of -5.6% (95% CI, -6.1%, -5.0%) and -4.5% (95% CI, -5.0%, -4.0%), respectively (p=0.012). Ischaemic heart disease mortality declined at a similar rate in urban and rural regions (APC -7.6% and -6.7% per annum, p=0.28). Absolute inequalities in IHD deaths persisted until 2015 when there were 49 (urban) and 70 (rural) IHD deaths per 100,000 people.

CONCLUSIONS

Ischaemic heart disease hospitalisations and mortality have declined considerably between 2001 and 2015 in both rural and urban areas, yet inequalities persist, suggesting more intensive preventive efforts are required to further reduce the burden of IHD in rural populations.

Acute myocardial infarction incidence and survival in Aboriginal and non-Aboriginal populations: an observational study in the Northern Territory of Australia, 1992-2014

OBJECTIVES

To examine long-term trends in acute myocardial infarction (AMI) incidence and survival among Aboriginal and non-Aboriginal people.

DESIGN

Retrospective cohort study.

SETTING, PARTICIPANTS

All first AMI hospital cases and deaths due to ischaemic heart disease in the Northern Territory of Australia (NT), 1992-2014.

MAIN OUTCOME MEASURES

Age standardised incidence, survival and mortality.

RESULTS

The upward trend in Aboriginal AMI incidence plateaued around 2007 for males and 2001 for females. AMI incidence decreased for non-Aboriginal population, consistent with the national trends. AMI incidence was higher and survival lower for males, for Aboriginal people and in older age groups. In 2014, the age standardised incidence was 881 and 579 per 100 000 for Aboriginal males and females, respectively, compared with 290 and 187 per 100 000 for non-Aboriginal counterparts. The incidence disparity between Aboriginal and non-Aboriginal population was much greater in younger than older age groups. Survival after an AMI improved over time, and more so for Aboriginal than non-Aboriginal patients, because of a decrease in prehospital deaths and improved survival of hospitalised cases.

CONCLUSIONS

There was an important breakpoint in increasing trends of Aboriginal AMI incidence between 2001 and 2007. The disparity in AMI survival between the NT Aboriginal and non-Aboriginal populations reduced over time as survival improved for both populations.

Challenges in Managing Acute Cardiovascular Diseases and Follow Up Care in Rural Areas: A Narrative Review

This narrative review explores relevant literature that is related to the challenges in implementing evidence-based management for clinicians in rural and remote areas, while primarily focussing on management of acute coronary syndrome (ACS) and follow up care. A targeted literature search around rural/urban differences in the management of ACS, cardiovascular disease, and cardiac rehabilitation identified multiple issues that are related to access, including the ability to pay, transport and geographic distances, delays in patients seeking care, access to diagnostic testing, and timely treatment in an appropriate facility. Workforce shortages or lack of ready access to relevant expertise, cultural differences, and complexity that arises from comorbidities and from geographical isolation amplified diagnostic challenges. Given the urgency in management of ACS, rural clinicians must act quickly to achieve optimal patient outcomes. New technologies and quality improvement approaches enable better access to rapid diagnosis, as well as specialist input and care. Achieving an uptake of cardiac rehabilitation in rural and remote settings poses challenges that may reduce with the use of alternative models to centre-based rehabilitation and use of modern technologies. Expediting improvement in cardiovascular outcomes and reducing rural disparities requires system changes and that clinicians embrace attention to prevention, emergency management, and follow up care in rural contexts.

Missed Acute Myocardial Infarction (MAMI) in a rural and regional setting

Background

Delay in treatment and/or failure to provide reperfusion in ST-segment elevation myocardial infarction (STEMI) impacts on morbidity and mortality. This occurs more often outside metropolitan areas yet the reasons for this are unclear. This study aimed to describe factors associated with missed diagnosis of acute myocardial infarction (MAMI) in a rural and regional setting.

Methods

Using a retrospective cohort design, patients who presented with STEMI and failed to receive reperfusion therapy within four hours were identified as MAMI. Univariate analyses were undertaken to identify differences in clinical characteristics between the treated STEMI group and the MAMI group. Mortality, 30-day readmission rates and length of hospital stay are reported.

Results

Of 100 patients identified as MAMI (70 male, 30 female), 24 died in hospital. Demographics and time from symptom onset were similar in the treated STEMI and MAMI groups. Of the MAMI patients who died, rural hospitals recorded the highest inpatient mortality (69.6% p = 0.008). MAMI patients compared to treated STEMI patients had higher 30 day readmission (31.6% vs 3.3%, p = 0.001) and longer length of stay (5.5 vs 4.3 days p = 0.029). Inaccurate identification of STEMI on electrocardiogram (72%) and diagnostic uncertainty (65%) were associated with MAMI. The Glasgow algorithm to identify STEMI was utilised on 57% of occasions, with 93% accuracy.

Conclusion

Mortality following MAMI is high particularly in smaller rural hospitals. MAMI results in increased length of stay and readmission rate. Electrocardiogram interpretation and diagnostic accuracy require improvement to determine if this improves patient outcomes.

Improving cardiovascular outcomes among Aboriginal Australians: Lessons from research for primary care

BACKGROUND

The Aboriginal people of Australia have much poorer health and social indicators and a substantial life expectancy gap compared to other Australians, with premature cardiovascular disease a major contributor to poorer health. This article draws on research undertaken to examine cardiovascular disparities and focuses on ways in which primary care practitioners can contribute to reducing cardiovascular disparities and improving Aboriginal health.

METHODS

The overall research utilised mixed methods and included data analysis, interviews and group processes which included Aboriginal people, service providers and policymakers. Workshop discussions to identify barriers and what works were recorded by notes and on whiteboards, then distilled and circulated to participants and other stakeholders to refine and validate information. Additional engagement occurred through circulation of draft material and further discussions. This report distils the lessons for primary care practitioners to improve outcomes through management that is attentive to the needs of Aboriginal people.

RESULTS

Aspects of primordial, primary and secondary prevention are identified, with practical strategies for intervention summarised. The premature onset and high incidence of Aboriginal cardiovascular disease make prevention imperative and require that primary care practitioners understand and work to address the social underpinnings of poor health. Doctors are well placed to reinforce the importance of healthy lifestyle at all visits to involve the family and to reduce barriers which impede early care seeking. Ensuring better information for Aboriginal patients and better integrated care for patients who frequently have complex needs and multi-morbidities will also improve care outcomes.

CONCLUSION

Primary care practitioners have an important role in improving Aboriginal cardiovascular care outcomes. It is essential that they recognise the special needs of their Aboriginal patients and work at multiple levels both outside and inside the clinic for prevention and management of disease. A toolkit of proactive and holistic opportunities for interventions is proposed.

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.

Rural-urban differentials in 30-day and 1-year mortality following first-ever heart failure hospitalisation in Western Australia: a population-based study using data linkage

OBJECTIVES

We examined differentials in short-term (30-day mortality) and 1-year mortality (in 30-day survivors) following index (first-ever) hospitalisation for heart failure (HF), between rural and metropolitan patients resident in Western Australia.

DESIGN

A population-based cohort study.

SETTING

Hospitalised patients in Western Australia, Australia.

PARTICIPANTS

Index patients aged 20-84 years with a first-ever hospitalisation for HF between 2000 and 2009 (with no prior admissions for HF in previous 10 years), identified using the Western Australia linked health data.

MAIN OUTCOME MEASURES

30-day and 1-year all-cause mortality (in 30-day survivors) following index admission for HF.

RESULTS

Of 17 379 index patients with HF identified, 25.9% (4499) were from rural areas. Rural patients were significantly younger at first HF hospitalisation than metropolitan patients. Aboriginal patients comprised 1.9% of metropolitan and 17.2% of rural patients. Despite some statistical differences, the prevalence of antecedents including ischaemic heart disease, hypertension, diabetes and chronic kidney disease was high (>20%) in both subpopulations. After adjusting for age only, patients from rural areas had a higher risk of 30-day death (OR 1.16 (95% CI 1.01 to 1.33)) and 1-year death in 30-day survivors (HR 1.11 (95% CI 1.01 to 1.23)). These relative risk estimates increased and remained significant after further progressive adjustments for Aboriginality, socioeconomic status, insurance status, emergency presentation, individual comorbidities and revascularisation with OR 1.25 (1.06 to 1.48) for 30-day mortality and HR 1.13 (1.02 to 1.27) for 1-year mortality. The addition of the weighted Charlson index to the 30-day model improved the 'c' statistic (under the receiver operating characteristic curve) from 0.656 (using a variation of administrative claims model) to 0.714.

CONCLUSIONS

Remoteness and variable access to healthcare can cause important disparities in health outcomes. Rural patients with HF in Western Australia have poorer risk-adjusted outcomes compared with metropolitan patients. This finding has important implications for chronic disease management and provision of health services in rural Australia.

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.

Closing the Gaps: competing estimates of Indigenous Australian life expectancy in the scientific literature

Objective: Closing the gap in life expectancy between Indigenous and other Australians within a generation is central to national Indigenous reform policy (Closing the Gap). Over time, various methods of estimating Indigenous life expectancy and with that, the life expectancy gap, have been adopted with differing, albeit non-comparable results. We present data on the extent of the gap and elucidate the pattern of use and interpretations of the different estimates of the gap, between 2007 and 2012.

Methods: An extensive search was conducted for all peer-reviewed health publications citing estimates of and/or discussing the life expectancy of Indigenous Australians, for the period 2007–2012.

Results: Five predominant patterns of citation of the gap estimates were identified: 20 years, 17 years, 15–20 years, 13 years, and 11.5 years for males and 9.7 years for females. Some authors misinterpret the most recent estimates as reflecting improvement from the 17-year figure, rather than the result of different methods of estimation. Support for the direct methods used to calculate Indigenous life expectancy is indicated.

Conclusions and Implications: A specific estimate of the life expectancy gap has not been established among stakeholders in Indigenous health. Agreement on the magnitude of the gap is arguably needed in order to evaluate strategies aimed at improving health outcomes for Indigenous Australians. Moreover, measuring progress towards ‘closing the gap’ depends on the availability of comparable estimates, using the same techniques of measurement to assess changes over time.