Incidence of Stroke in Indigenous Populations of Countries With a Very High Human Development Index: A Systematic Review

BACKGROUND AND OBJECTIVES

Cardiovascular disease contributes significantly to disease burden among many Indigenous populations. However, data on stroke incidence in Indigenous populations are sparse. We aimed to investigate what is known of stroke incidence in Indigenous populations of countries with a very high Human Development Index (HDI), locating the research in the broader context of Indigenous health.

METHODS

We identified population-based stroke incidence studies published between 1990 and 2022 among Indigenous adult populations of developed countries using PubMed, Embase, and Global Health databases, without language restriction. We excluded non-peer-reviewed sources, studies with fewer than 10 Indigenous people, or not covering a 35- to 64-year minimum age range. Two reviewers independently screened titles, abstracts, and full-text articles and extracted data. We assessed quality using "gold standard" criteria for population-based stroke incidence studies, the Newcastle-Ottawa Scale for risk of bias, and CONSIDER criteria for reporting of Indigenous health research. An Indigenous Advisory Board provided oversight for the study.

RESULTS

From 13,041 publications screened, 24 studies (19 full-text articles, 5 abstracts) from 7 countries met the inclusion criteria. Age-standardized stroke incidence rate ratios were greater in Aboriginal and Torres Strait Islander Australians (1.7-3.2), American Indians (1.2), Sámi of Sweden/Norway (1.08-2.14), and Singaporean Malay (1.7-1.9), compared with respective non-Indigenous populations. Studies had substantial heterogeneity in design and risk of bias. Attack rates, male-female rate ratios, and time trends are reported where available. Few investigators reported Indigenous stakeholder involvement, with few studies meeting any of the CONSIDER criteria for research among Indigenous populations.

DISCUSSION

In countries with a very high HDI, there are notable, albeit varying, disparities in stroke incidence between Indigenous and non-Indigenous populations, although there are gaps in data availability and quality. A greater understanding of stroke incidence is imperative for informing effective societal responses to socioeconomic and health disparities in these populations. Future studies into stroke incidence in Indigenous populations should be designed and conducted with Indigenous oversight and governance to facilitate improved outcomes and capacity building.

REGISTRATION INFORMATION

PROSPERO registration: CRD42021242367.

Determining the Optimal Methodology for Identifying Incident Stroke Deaths Using Administrative Datasets Within Australia

BACKGROUND AND AIM

Quantifying stroke incidence and mortality is crucial for disease surveillance and health system planning. Administrative data offer a cost-effective alternative to "gold standard" population-based studies. However, the optimal methodology for establishing stroke deaths from administrative data remains unclear. We aimed to determine the optimal method for identifying stroke-related deaths in administrative datasets as the fatal component of stroke incidence, comparing counts derived using underlying and all causes of death (CoD).

METHOD

Using whole-population multijurisdictional person-level linked data from hospital and death datasets from South Australia, the Northern Territory, and Western Australia, we identified first-ever stroke events between 2012 and 2015, using underlying CoD and all CoD to identify fatal stroke counts. We determined the 28-day case fatality for both counts and compared results with gold standard Australian population-based stroke incidence studies.

RESULTS

The total number of incident stroke events was 16,150 using underlying CoD and 18,074 using all CoD. Case fatality was 24.7% and 32.7% using underlying and all CoD, respectively. Case fatality using underlying CoD was similar to that observed in four Australian "gold standard" population-based studies (20%-24%).

CONCLUSIONS

Underlying CoD generates fatal incident stroke estimates more consistent with population-based studies than estimates based on stroke deaths identified from all-cause fields in death registers.

A Review of Cardiac Surgical Procedures and Their Outcomes for Paediatric Rheumatic Heart Disease in Western Australia

INTRODUCTION

Surgical intervention is an important treatment modality for advanced rheumatic heart disease (RHD). This study aimed to describe patient characteristics and outcomes from cardiac surgery for RHD in patients referred to the only tertiary paediatric hospital in Western Australia.

METHODS

An analysis of patient characteristics and cardiac surgery outcomes in patients with RHD was undertaken, using data from clinical cardiac databases, medical notes, and correspondence from rural outreach clinics.

RESULTS

29 patients (59% female, 97% Aboriginal, Māori or Pacific Islander) underwent 41 valve interventions over 34 cardiac surgeries for RHD between 2000-2018. Median age at first surgery was 12.2 (range 4-16) years. Severe mitral regurgitation (MR) was the most common indication for primary surgery (62%), followed by mixed mitral regurgitation/aortic regurgitation (21%) and severe aortic regurgitation (17%). Mitral valve repair was the most common valve intervention (56%). Two patients had mitral valve replacement (MVR) at first operation, two patients had MVR at second operation and two had MVR at third operation. There was no early mortality. One patient required early (<30 days) reoperation for aortic valve repair failure. Two patients had late reoperations at 3.3 and 6.1 months after the first procedure for MR. Four (14%) patients experienced documented ARF recurrences. Late mortality occurred in 3 (10%) patients, all due to cardiac causes. On last follow-up echocardiogram 5 patients (17%) had moderate MR and none had severe MR.

CONCLUSIONS

This is the first study to describe characteristics and outcomes in WA paediatric patients having surgery for RHD. Outcomes are comparable to similar studies, with favourable long-term survival.

Fracture Risk Increases After Stroke or Transient Ischemic Attack and Is Associated With Reduced Quality of Life

BACKGROUND

Fractures are a serious consequence following stroke, but it is unclear how these events influence health-related quality of life (HRQoL). We aimed to compare annualized rates of fractures before and after stroke or transient ischemic attack (TIA), identify associated factors, and examine the relationship with HRQoL after stroke/TIA.

METHODS

Retrospective cohort study using data from the Australian Stroke Clinical Registry (2009-2013) linked with hospital administrative and mortality data. Rates of fractures were assessed in the 1-year period before and after stroke/TIA. Negative binomial regression, with censoring at death, was used to identify factors associated with fractures after stroke/TIA. Respondents provided HRQoL data once between 90 and 180 days after stroke/TIA using the EuroQoL 5-dimensional 3-level instrument. Adjusted logistic regression was used to assess differences in HRQoL at 90 to 180 days by previous fracture.

RESULTS

Among 13 594 adult survivors of stroke/TIA (49.7% aged ≥75 years, 45.5% female, 47.9% unable to walk on admission), 618 fractures occurred in the year before stroke/TIA (45 fractures per 1000 person-years) compared with 888 fractures in the year after stroke/TIA (74 fractures per 1000 person-years). This represented a relative increase of 63% (95% CI, 47%-80%). Factors associated with poststroke fractures included being female (incidence rate ratio [IRR], 1.34 [95% CI, 1.05-1.72]), increased age (per 10-year increase, IRR, 1.35 [95% CI, 1.21-1.50]), history of prior fracture(s; IRR, 2.56 [95% CI, 1.77-3.70]), and higher Charlson Comorbidity Scores (per 1-point increase, IRR, 1.18 [95% CI, 1.10-1.27]). Receipt of stroke unit care was associated with fewer poststroke fractures (IRR, 0.67 [95% CI, 0.49-0.93]). HRQoL at 90 to 180 days was worse among patients with prior fracture across the domains of mobility, self-care, usual activities, and pain/discomfort.

CONCLUSIONS

Fracture risk increases substantially after stroke/TIA, and a history of these events is associated with poorer HRQoL at 90 to 180 days after stroke/TIA.

Incidence of Stroke in the Aboriginal and Non-Aboriginal Populations of Australia: A Data Linkage Study

BACKGROUND

Most estimates of stroke incidence among Aboriginal and Torres Strait Islander (hereinafter Aboriginal) Australians are confined to single regions and include small sample sizes. We aimed to measure and compare stroke incidence in Aboriginal and non-Aboriginal residents across central and western Australia.

METHODS

Whole-population multijurisdictional person-linked data from hospital and death datasets were used to identify stroke admissions and stroke-related deaths (2001-2015) in Western Australia, South Australia, and the Northern Territory. Fatal (including out-of-hospital deaths) and nonfatal incident (first-ever) strokes in patients aged 20-84 years were identified during the 4-year study period (2012-2015), using a 10-year lookback period to exclude people with prior stroke. Incidence rates per 100 000 population/year were estimated for Aboriginal and non-Aboriginal populations, age-standardized to the World Health Organization World Standard population.

RESULTS

In a population of 3 223 711 people (3.7% Aboriginal), 11 740 incident (first-ever) strokes (20.6% regional/remote location of residence; 15.6% fatal) were identified from 2012 to 2015, 675 (5.7%) in Aboriginal people (73.6% regional/remote; 17.0% fatal). Median age of Aboriginal cases (54.5 years; 50.1% female) was 16 years younger than non-Aboriginal cases (70.3 years; 44.1% female; P<0.001), with significantly greater prevalence of comorbidities. Age-standardized stroke incidence in Aboriginal people (192/100 000 [95% CI, 177-208]) was 2.9-fold greater than in non-Aboriginal people (66/100 000 [95% CI, 65-68]) aged 20-84 years; fatal incidence was 4.2-fold greater (38/100 000 [95% CI, 31-46] versus 9/100 000 [95% CI, 9-10]). Disparities were particularly apparent at younger ages (20-54 years), where age-standardized stroke incidence was 4.3-fold greater in Aboriginal people (90/100 000 [95% CI, 81-100]) than non-Aboriginal people (21/100 000 [95% CI, 20-22]).

CONCLUSIONS

Stroke occurred more commonly, and at younger ages, in Aboriginal than non-Aboriginal populations. Greater prevalence of baseline comorbidities was present in the younger Aboriginal population. Improved primary prevention is required. To optimize stroke prevention, interventions should include culturally appropriate community-based health promotion and integrated support for nonmetropolitan health services.

Rheumatic heart disease mortality in Indigenous and non-Indigenous Australians between 2010 and 2017

OBJECTIVES

To generate contemporary age-specific mortality rates for Indigenous and non-Indigenous Australians aged <65 years who died from rheumatic heart disease (RHD) between 2013 and 2017, and to ascertain the underlying causes of death (COD) of a prevalent RHD cohort aged <65 years who died during the same period.

METHODS

For this retrospective, cross-sectional epidemiological study, Australian RHD deaths for 2013-2017 were investigated by first, mortality rates generated using Australian Bureau of Statistics death registrations where RHD was a coded COD, and second COD analyses of death records for a prevalent RHD cohort identified from RHD register and hospitalisations. All analyses were undertaken by Indigenous status and age group (0-24, 25-44, 45-64 years).

RESULTS

Age-specific RHD mortality rates per 100 000 were 0.32, 2.63 and 7.41 among Indigenous 0-24, 25-44 and 45-64 year olds, respectively, and the age-standardised mortality ratio (Indigenous vs non-Indigenous 0-64 year olds) was 14.0. Within the prevalent cohort who died (n=726), RHD was the underlying COD in 15.0% of all deaths, increasing to 24.6% when RHD was included as associated COD. However, other cardiovascular and non-cardiovascular conditions were the underlying COD in 34% and 43% respectively.

CONCLUSION

Premature mortality in people with RHD aged <65 years has approximately halved in Australia since 1997-2005, most notably among younger Indigenous people. Mortality rates based solely on underlying COD potentially underestimates true RHD mortality burden. Further strategies are required to reduce the high Indigenous to non-Indigenous mortality rate disparity, in addition to optimising major comorbidities that contribute to non-RHD mortality.

Large Burden of Stroke Incidence in People with Cardiac Disease: A Linked Data Cohort Study

Purpose

People with cardiac disease have 2-4 times greater risk of stroke than the general population. We measured stroke incidence in people with coronary heart disease (CHD), atrial fibrillation (AF) or valvular heart disease (VHD).

Methods

We used a person-linked hospitalization/mortality dataset to identify all people hospitalized with CHD, AF or VHD (1985-2017), and stratified them as pre-existing (hospitalized 1985-2012 and alive at October 31, 2012) or new (first-ever cardiac hospitalization in the five-year study period, 2012-2017). We identified first-ever strokes occurring from 2012 to 2017 in patients aged 20-94 years and calculated age-specific and age-standardized rates (ASR) for each cardiac cohort.

Results

Of the 175,560 people in the cohort, most had CHD (69.9%); 16.3% had multiple cardiac conditions. From 2012-17, 5871 first-ever strokes occurred. ASRs were greater in females than males in single and multiple condition cardiac groups, largely driven by rates in females aged ≥75 years, with stroke incidence in this age group being at least 20% greater in females than males in each cardiac subgroup. In females aged 20-54 years, stroke incidence was 4.9-fold greater in those with multiple versus single cardiac conditions. This differential declined with increasing age. Non-fatal stroke incidence was greater than fatal stroke in all age groups except in the 85-94 age group. Incidence rate ratios were up to 2-fold larger in new versus pre-existing cardiac disease.

Conclusion

Stroke incidence in people with cardiac disease is substantial, with older females, and younger patients with multiple cardiac conditions, at elevated risk. These patients should be specifically targeted for evidence-based management to minimize the burden of stroke.

Abstract 140: The Incidence Of Stroke In Indigenous Populations Of Countries With A Very High Human Development Index: A Systematic Review

Introduction: Despite known socioeconomic and health disparities affecting Indigenous populations in developed countries, stroke incidence data are sparse. With Indigenous Advisory Board oversight, we undertook a systematic review to compare Indigenous with non-Indigenous stroke incidence rates in countries with a very high Human Development Index (HDI).

Methods: We identified population-based stroke incidence studies published from 1990-2022 in Indigenous adult populations of developed countries using PubMed, EMBASE and Global Health databases, without language restriction. We excluded non-peer-reviewed sources, studies with <10 Indigenous people, or studies not covering a 35-64 year minimum age range. Two reviewers independently screened titles, abstracts, and full texts, and extracted data. We assessed quality using "ideal" criteria for population-based stroke incidence studies, the Newcastle-Ottawa Scale for risk of bias, and CONSIDER criteria for Indigenous research.

Results: Among 13,041 publications, 24 studies (19 full text, 5 abstracts) from 7 countries met inclusion criteria. Compared with respective non-Indigenous populations (Fig 1), age-standardised incidence rates were greater in Aboriginal and Torres Strait Islander Australians (ratios ranging from 1.7-3.2), American Indians (1.2), Sámi of Sweden/Norway (1.08-2.14), and Singaporean Malay (1.7-1.9), with higher rate ratios at younger ages. Studies had substantial heterogeneity in design and risk of bias. Few investigators reported Indigenous stakeholder involvement.

Conclusions: In countries with a very high HDI, available data suggest marked disparities in stroke incidence in Indigenous populations, although there are gaps in data availability and quality. Indigenous stakeholder involvement in studies is infrequently reported. A greater understanding of stroke incidence in these populations is imperative for informing effective societal responses.

Corrigendum to: Evolution of non-fatal burden estimates for cardiovascular disease in Australia: a comparison of national and state-wide methodology of burden of disease

Objective Burden of disease studies measure the impact of disease at the population level;however, methods and data sources for estimates of prevalence vary. Using a selection of cardiovascular diseases, we aimed to describe the implications of using different disease models and linked administrative data on prevalence estimation within three Australian burden of disease studies. Methods Three different methods (A = 2011 Australian Burden of Disease Study; B = 2015 Australian Burden of Disease Study; C = 2015 Western Australian Burden of Disease Study), which used linked data, were used to compare prevalence estimates of stroke, aortic aneurysm, rheumatic valvular heart disease (VHD) and non-rheumatic VHD. We applied these methods to 2015 Western Australian data, and calculated crude overall and age-specific prevalence for each condition. Results Overall, Method C produced estimates of cardiovascular prevalence that were lower than the other methods, excluding non-rheumatic VHD. Prevalence of acute and chronic stroke was up to one-third higher in Method A and B compared to Method C. Aortic aneurysms had the largest change in prevalence, with Method A producing an eight-fold higher estimate compared to Method C, but Method B was 10-20% lower. Estimates of VHD varied dramatically, with an up to six-fold change in prevalence in Method C due to substantial changes to disease models and the use of linked data. Conclusions Prevalence estimates require the best available data sources, updated disease models and constant review to inform government policy and health reform. Availability of nation-wide linked data will markedly improve future burden estimates.

Evolution of non-fatal burden estimates for cardiovascular disease in Australia: a comparison of national and state-wide methodology of burden of disease

Objective Burden of disease studies measure the impact of disease at the population level;however, methods and data sources for estimates of prevalence vary. Using a selection of cardiovascular diseases, we aimed to describe the implications of using different disease models and linked administrative data on prevalence estimation within three Australian burden of disease studies. Methods Three different methods (A = 2011 Australian Burden of Disease Study; B = 2015 Australian Burden of Disease Study; C = 2015 Western Australian Burden of Disease Study), which used linked data, were used to compare prevalence estimates of stroke, aortic aneurysm, rheumatic valvular heart disease (VHD) and non-rheumatic VHD. We applied these methods to 2015 Western Australian data, and calculated crude overall and age-specific prevalence for each condition. Results Overall, Method C produced estimates of cardiovascular prevalence that were lower than the other methods, excluding non-rheumatic VHD. Prevalence of acute and chronic stroke was up to one-third higher in Method A and B compared to Method C. Aortic aneurysms had the largest change in prevalence, with Method A producing an eight-fold higher estimate compared to Method C, but Method B was 10-20% lower. Estimates of VHD varied dramatically, with an up to six-fold change in prevalence in Method C due to substantial changes to disease models and the use of linked data. Conclusions Prevalence estimates require the best available data sources, updated disease models and constant review to inform government policy and health reform. Availability of nation-wide linked data will markedly improve future burden estimates.

Burden of stroke incidence among atrial fibrillation, valvular heart disease and coronary heart disease patients

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Health and Medical Research Council of Australia

Background

The public health burden of stroke has continued to increase in recent decades. In patients with cardiac disease, the risk of stroke is 2-4 times higher than in the general population, and therefore investigating stroke incidence in these patients is important for identifying opportunities for stroke prevention.

Purpose

We aimed to measure the incidence of stroke in people with atrial fibrillation (AF), valvular heart disease (VHD) or coronary heart disease (CHD) to assess the risk of stroke by age, sex, pre-existing vs new cardiac disease, and nonfatal/fatal status.

Methods

We used a person-linked hospitalisation/mortality dataset to identify all people hospitalized with AF, VHD or CHD from 1985 to 2017 in a whole-population setting. These cardiac cases were stratified as pre-existing (hospitalised between 1985 and 2012, who were alive at 31st October 2012 with no history of stroke) or new (first-ever cardiac hospitalisation from November 1st, 2012 to October 31st, 2017, with no prior hospitalisation for AF, VHD or CHD, and no history of stroke). Patients aged 20-94 years were included in the study. Pre-existing and new cardiac cases were followed over the 5-year study period (1st November 2012 to 31st December 2017) to identify first-ever stroke events. Age-specific and age-standardised rates (ASR) for stroke incidence were calculated for all cardiac cases combined, and separately for pre-existing and new cases.

Results

The cohort comprised 175,560 patients. The majority of the cohort had a single cardiac condition (55.7% CHD; 23.0% AF; 5.0% VHD), while 16.3% of patients had multiple cardiac conditions. There were 5,871 (3.3%) first-ever strokes (5.2% in AF patients, 4.0% in VHD, 2.8% in CHD). Stroke incidence ASRs were greater in women than men across each cardiac group and irrespective of the presence of single or multiple cardiac conditions (Figure). This was largely driven by women aged ≥75 years, with stroke incidence being greater in women than men in each cardiac group. In women aged 20-54 years, there was a 4.9-fold higher incidence of stroke in those with multiple versus single cardiac conditions, and this differential appeared to decline with increasing age (Figure). Incidence of non-fatal strokes was greater than fatal stroke in all age groups except among 85-94 year olds. Incidence rates in each cardiac group were between 1.2 and 2.4 times higher in those with new versus pre-existing cardiac disease.

Conclusions

Stroke incidence is substantial in patients with cardiac disease. Older women with AF and VHD had the highest stroke rates overall, although younger patients with multiple cardiac conditions were also at high risk. These cardiac patients should be targeted for evidence-based management to minimise their stroke risk, especially in the period immediately following diagnosis when risk is highest.

Figure Legend. Age-specific and age-standardised stroke incidence rates in all cardiac cases.

Living with Rheumatic Heart Disease at the Intersection of Biomedical and Aboriginal Worldviews

Rheumatic heart disease (RHD) significantly impacts the lives of First Nations Australians. Failure to eliminate RHD is in part attributed to healthcare strategies that fail to understand the lived experience of RHD. To rectify this, a PhD study was undertaken in the Northern Territory (NT) of Australia, combining Aboriginal ways of knowing, being and doing with interviews (24 participants from clinical and community settings) and participant observation to privilege Aboriginal voices, including the interpretations and experiences of Aboriginal co-researchers (described in the adjunct article). During analysis, Aboriginal co-researchers identified three interwoven themes: maintaining good feelings; creating clear understanding (from good information); and choosing a good djalkiri (path). These affirm a worldview that prioritises relationships, positive emotions and the wellbeing of family/community. The findings demonstrate the inter-connectedness of knowledge, choice and behaviour that become increasingly complex in stressful and traumatic health, socioeconomic, political, historical and cultural contexts. Not previously heard in the RHD domain, the findings reveal fundamental differences between Aboriginal and biomedical worldviews contributing to the failure of current approaches to communicating health messages. Mitigating this, Aboriginal co-researchers provided targeted recommendations for culturally responsive health encounters, including: communicating to create positive emotions; building trust; and providing family and community data and health messages (rather than individualistic).

Long-term outcomes following rheumatic heart disease diagnosis in Australia

Aims 

Rheumatic heart disease (RHD) is a major contributor to cardiac morbidity and mortality globally. This study aims to estimate the probability and predictors of progressing to non-fatal cardiovascular complications and death in young Australians after their first RHD diagnosis.

Methods and results 

This retrospective cohort study used linked RHD register, hospital, and death data from five Australian states and territories (covering 70% of the whole population and 86% of the Indigenous population). Progression from uncomplicated RHD to all-cause death and non-fatal cardiovascular complications (surgical intervention, heart failure, atrial fibrillation, infective endocarditis, and stroke) was estimated for people aged <35 years with first-ever RHD diagnosis between 2010 and 2018, identified from register and hospital data. The study cohort comprised 1718 initially uncomplicated RHD cases (84.6% Indigenous; 10.9% migrant; 63.2% women; 40.3% aged 5–14 years; 76.4% non-metropolitan). The composite outcome of death/cardiovascular complication was experienced by 23.3% (95% confidence interval: 19.5–26.9) within 8 years. Older age and metropolitan residence were independent positive predictors of the composite outcome; history of acute rheumatic fever was a negative predictor. Population group (Indigenous/migrant/other Australian) and sex were not predictive of outcome after multivariable adjustment.

Conclusion 

This study provides the most definitive and contemporary estimates of progression to major cardiovascular complication or death in young Australians with RHD. Despite access to the publically funded universal Australian healthcare system, one-fifth of initially uncomplicated RHD cases will experience one of the major complications of RHD within 8 years supporting the need for programmes to eradicate RHD.

Healing Right Way: study protocol for a stepped wedge cluster randomised controlled trial to enhance rehabilitation services and improve quality of life in Aboriginal Australians after brain injury

INTRODUCTION

Despite higher incidence of brain injury among Aboriginal compared with non-Aboriginal Australians, suboptimal engagement exists between rehabilitation services and Aboriginal brain injury survivors. Aboriginal patients often feel culturally insecure in hospital and navigation of services post discharge is complex. Health professionals report feeling ill-equipped working with Aboriginal patients. This study will test the impact of a research-informed culturally secure intervention model for Aboriginal people with brain injury. METHODS AND ANALYSIS: Design: Stepped wedge cluster randomised control trial design; intervention sequentially introduced at four pairs of healthcare sites across Western Australia at 26-week intervals.Recruitment: Aboriginal participants aged ≥18 years within 4 weeks of an acute stroke or traumatic brain injury.Intervention: (1) Cultural security training for hospital staff and (2) local, trial-specific, Aboriginal Brain Injury Coordinators supporting participants.Primary outcome: Quality-of-life using EuroQOL-5D-3L (European Quality of Life scale, five dimensions, three severity levels) Visual Analogue Scale score at 26 weeks post injury. Recruitment of 312 participants is estimated to detect a difference of 15 points with 80% power at the 5% significance level. A linear mixed model will be used to assess the between-condition difference.Secondary outcome measures: Modified Rankin Scale, Functional Independence Measure, Modified Caregiver Strain Index, Hospital Anxiety and Depression Scale at 12 and 26 weeks post injury, rehabilitation occasions of service received, hospital compliance with minimum care processes by 26 weeks post injury, acceptability of Intervention Package, feasibility of Aboriginal Brain Injury Coordinator role.Evaluations: An economic evaluation will determine the potential cost-effectiveness of the intervention. Process evaluation will document fidelity to study processes and capture changing contexts including barriers to intervention implementation and acceptability/feasibility of the intervention through participant questionnaires at 12 and 26 weeks.

ETHICS AND DISSEMINATION

The study has approvals from Aboriginal, university and health services human research ethics committees. Findings will be disseminated through stakeholder reports, participant workshops, peer-reviewed journal articles and conference papers.

TRIAL REGISTRATION NUMBER

ACTRN12618000139279.

Study protocol for a prospective process evaluation of a culturally secure rehabilitation programme for Aboriginal Australians after brain injury: the Healing Right Way project

INTRODUCTION

Aboriginal and Torres Strait Islander (hereafter respectfully referred to as Aboriginal) people are Australia's First Peoples, having the longest continuous culture in the world and deep spiritual connections with ancestral land. Improvements in their health and well-being is a major policy goal of Australian governments, as the legacy of colonisation and disruption of cultural practices contribute to major health challenges. Lack of culturally secure services impacts participation of Aboriginal people in health services. Aboriginal people with a brain injury typically experience poor access to rehabilitation and support following hospital discharge. 'Healing Right Way' (HRW) is a randomised control trial aiming to improve access to interdisciplinary and culturally secure rehabilitation services for Aboriginal people after brain injury in Western Australia, improve health outcomes and provide the first best practice model. This protocol is for the process evaluation of the HRW trial.

METHODS AND ANALYSIS

A prospective mixed methods process evaluation will use the Consolidated Framework for Implementation Research to evaluate implementation and intervention processes involved in HRW. Data collection includes qualitative and quantitative data from all sites during control and intervention phases, relating to three categories: (1) implementation of trial processes; (2) cultural security training; and (3) Aboriginal Brain Injury Coordinator role. Additional data elements collected from HRW will support the process evaluation regarding fidelity and intervention integrity. Iterative cross-sectional and longitudinal data synthesis will support the implementation of HRW, interpretation of findings and inform future development and implementation of culturally secure interventions for Aboriginal people.

ETHICS AND DISSEMINATION

This process evaluation was reviewed by The University of Western Australia Human Research Ethics Committee (RA/4/20/4952). Evaluation findings will be disseminated via academic mechanisms, seminars at trial sites, regional Aboriginal health forums, peak bodies for Aboriginal health organisations and the Australian Indigenous HealthInfoNet (https://healthinfonet.ecu.edu.au/).

TRIAL REGISTRATION NUMBER

ACTRN12618000139279.

"You felt like a prisoner in your own self, trapped": the experiences of Aboriginal people with acquired communication disorders

PURPOSE

Aboriginal Australians are under-represented in brain injury rehabilitation services despite a high incidence of both stroke and traumatic brain injury in this population. This study aimed to explore the experiences of Aboriginal Australian adults with acquired communication disorders (ACDs) after brain injury for the first time to inform the development of accessible and culturally secure service delivery models.

METHODS AND MATERIALS

Semi-structured interviews were undertaken with 32 Aboriginal people who had experienced a brain injury resulting in ACDs (aged 35-79 years) and 18 family members/carers across Western Australia. Thematic analysis identified common themes across participants.

RESULTS

Overall themes related to communication (both related to the communication disorder and general healthcare interactions), health and social contexts, recovery, and support, being away from family and country, knowledge and beliefs about brain injury, and follow-up.

CONCLUSIONS

An increase in healthcare staff's appreciation of the health and social contexts of Aboriginal people after brain injury is needed in order to improve communication with Aboriginal patients and the ability to offer accessible rehabilitation services. Ongoing support is required, with cultural identity noted as key to ensuring cultural security and ultimately recovery. Involvement of family and other Aboriginal people in recovery processes, as well as access to relevant Aboriginal languages and proximity to ancestral lands is central.Implications for rehabilitationAcknowledgment of cultural identity and strengths through involvement of extended family and Aboriginal Hospital Liaison Officers, access to language and proximity to country all central to rehabilitation planning for Aboriginal people after brain injury.Cultural security training for rehabilitation staff is recommended focusing on clear two-way communication skills to make medical information accessible for Aboriginal patients and to listen to patients' concerns in a way that respects cultural context.Information regarding practical support and implications for ongoing management of life after brain injury (for the person and their family) is essential, and should supplement the medical-related information provided.Follow-up post discharge from hospital best facilitated through establishing contact with local Aboriginal community through Aboriginal community controlled health services, community elders, and Aboriginal health workers across organisations.

Can the CHA2 DS2 -VA schema be used to decide on anticoagulant therapy in Aboriginal and other Australians with non-valvular atrial fibrillation?

The Australasian guidelines recommend use of the CHA₂ DS₂ -VA schema to stratify ischaemic stroke risk in patients with non-valvular atrial fibrillation (N-VAF) and determine risk thresholds for recommending oral anticoagulant (OAC) therapy. However, the CHA₂ DS₂ -VA score has not been validated in a representative Australian population cohort with N-VAF, including in Aboriginal people who are known to have a higher age-adjusted stroke risk than other Australians. In a retrospective data-linkage study of 49 114 patients aged 24-84 years with N-VAF, 40.0% women and 2.5% Aboriginal, we found that patients with a CHA₂ DS₂ -VA score >2 had high annual stroke rates (>2%) that would justify OAC therapy. This occurred regardless of Aboriginal status. Non-Aboriginal patients with a CHA₂ DS₂ -VA score of 0 had a mean annual stroke rate of 0.4%, and hence were not likely to benefit from antithrombotic therapy. However, Aboriginal patients with a zero CHA₂ DS₂ -VA score had a significantly higher annual stroke rate of 0.9%, and could potentially obtain net clinical benefit from anticoagulation, primarily with the safer non-vitamin K antagonist OAC. We conclude that clinicians can confidently use the CHA₂ DS₂ -VA score to make decisions regarding anticoagulation in accordance with stroke risk in patients with N-VAF, except in Aboriginal people in whom the risk score was unable to identify those at truly low risk of stroke.

The Incidence of Stroke in Indigenous Populations of Countries With a Very High Human Development Index: A Systematic Review Protocol

Background and Aims: Despite known Indigenous health and socioeconomic disadvantage in countries with a Very High Human Development Index, data on the incidence of stroke in these populations are sparse. With oversight from an Indigenous Advisory Board, we will undertake a systematic review of the incidence of stroke in Indigenous populations of developed countries or regions, with comparisons between Indigenous and non-Indigenous populations of the same region, though not between different Indigenous populations. Methods: Using PubMed, OVID-EMBASE, and Global Health databases, we will examine population-based incidence studies of stroke in Indigenous adult populations of developed countries published 1990-current, without language restriction. Non-peer-reviewed sources, studies including <10 Indigenous People, or with insufficient data to determine incidence, will be excluded. Two reviewers will independently validate the search strategies, screen titles and abstracts, and record reasons for rejection. Relevant articles will undergo full-text screening, with standard data extracted for all studies included. Quality assessment will include Sudlow and Warlow's criteria for population-based stroke incidence studies, the Newcastle-Ottawa Scale for risk of bias, and the CONSIDER checklist for Indigenous research. Results: Primary outcomes include crude, age-specific and/or age-standardized incidence of stroke. Secondary outcomes include overall stroke rates, incidence rate ratio and case-fatality. Results will be synthesized in figures and tables, describing data sources, populations, methodology, and findings. Within-population meta-analysis will be performed if, and where, methodologically sound and comparable studies allow this. Conclusion: We will undertake the first systematic review assessing disparities in stroke incidence in Indigenous populations of developed countries. Data outputs will be disseminated to relevant Indigenous stakeholders to inform public health and policy research.

Investigating inequities in cardiovascular care and outcomes for Queensland Aboriginal and Torres Strait Islander people: protocol for a hospital-based retrospective cohort data linkage project

INTRODUCTION

Cardiovascular disease (CVD) represents a significant burden of disease for Aboriginal and Torres Strait Islander people, a population that continues to experience a lower life expectancy than other Australians. The aim of the Better Cardiac Care Data Linkage project is to describe patient care pathways and to identify disparities in care and health outcomes between Aboriginal and Torres Strait Islander people and other Queensland residents diagnosed with CVD in the state of Queensland.

METHODS

This is a population-based retrospective cohort study using linked regional, state and national health and administrative data collections to describe disparities in CVD healthcare in primary and secondary prevention settings and during hospitalisation. The CVD cohort will be identified from the Queensland Hospital Admitted Patient Data Collection for admissions that occurred between 1 July 2010 and 31 June 2016 and will include relevant International Classification of Disease codes for ischaemic heart disease, congestive heart failure, stroke, acute rheumatic fever and rheumatic heart disease. Person-level data will be linked by Data Linkage Queensland and the Australian Institute of Health and Welfare (AIHW) in accordance with ethical and public health approvals to describe the patient journey prior to, during and post the hospital admission.

ANALYSIS

This project will focus largely on descriptive epidemiological measures and multivariate analysis of clinical care standards and outcomes for Aboriginal and Torres Strait Islander people compared with other Queenslanders, including identification of risk factors for suboptimal care and change over time. Variation in care pathways and patient outcomes will be compared by Indigenous status, sex, age group, remoteness of residence, year of index hospitalisation and socioeconomic status. Cox models for time-to-event data and mixed models or generalised estimating equations for longitudinal data will be used to measure change over time where temporal effects exist.

ETHICS AND DISSEMINATION

Ethical approval has been granted by Human Research Ethics Committees of the Prince Charles Hospital (HREC/15/QPCH/289) and the AIHW (EO2016-1-233). The Northern Territory Department of Health and Menzies School of Health Research have also provided reciprocal ethical approval of the project (HREC 2019-3490). The deidentified results will be summarised in a report and shared with investigators, advisory groups, Queensland Health and key stakeholders. Findings will be disseminated through workshops, conferences and will be published in peer-reviewed journals.

Occurrence and timely management of problems requiring prompt intervention among Indigenous compared with non-Indigenous Australian palliative care patients: a multijurisdictional cohort study

OBJECTIVES

Anticipation and prompt relief of symptoms among patients with a life-limiting illness is a core element of palliative care. Indigenous Australians commonly encounter cultural barriers in healthcare that may impair outcomes. The Palliative Care Outcomes Collaboration collects patient care data for the purposes of continuous quality improvement and benchmarking, with each recorded care episode divided into phases that reflect a patient's condition. We aimed to investigate differences between Indigenous and non-Indigenous patients in the occurrence and duration of 'unstable' phases (which indicate unanticipated deterioration in a patient's condition or circumstances), and determine attainment of the relevant benchmark (resolution of unstable phases in ≤3 days in 90% of cases) for both groups.

DESIGN

Cohort study.

SETTING

Australia-wide hospital-based and community-based specialist palliative care (1 January 2010 to 30 June 2015).

PARTICIPANTS

139 556 (1502 Indigenous and 138 054 non-Indigenous) adult patients.

OUTCOME MEASURES

Indigenous and non-Indigenous patients were compared on (1) the risk of a phase being categorised as unstable, (2) the duration of unstable phases, and (3) the risk of unstable phases being prolonged (>3 days). Crude and adjusted estimates were produced from three-level robust Poisson regression and complementary log-log discrete time survival models.

RESULTS

Unstable phases occurred with similar frequency overall among Indigenous and non-Indigenous patients (adjusted relative risks 1.06; 95% CI 1.00 to 1.11; not significant after correction for multiple comparisons). The duration and risk of prolongation of unstable phases were similar in both patient groups, with no significant differences evident among subgroups. The benchmark was not met for either Indigenous or non-Indigenous patients (unstable phase duration >3 days in 24.3% vs 25.5%; p=0.398).

CONCLUSIONS

Despite well-documented shortcomings of healthcare for Indigenous Australians, there is no clear evidence of greater occurrence or prolongation of unanticipated problems among Indigenous patients accessing specialist palliative care services in hospital or the community.

Understanding valvular heart disease in the dental setting

BACKGROUND

Limited evidence is available regarding dentists' knowledge and interpretation of infective endocarditis (IE) prophylaxis guidelines. The aim of this study was to determine understanding and management of rheumatic and non-rheumatic valvular heart disease (VHD) in the dental setting in Western Australia (WA).

METHODS

A cross-sectional survey of dentists within Perth utilized an online Qualtrics questionnaire developed after consultation with stakeholders. A sampling frame was compiled from the Australian Health Practitioner Regulation Agency with contact details obtained from the White Pages (online), using five quintiles of Socio-Economic Indexes for Areas according to dentist's place of practice.

RESULTS

Of 41 (13.7% of 300 approached) dentists completing the survey (95.1% general dentists, mean years of practice = 15.6), 90.2% reported following the Australian Therapeutic Guidelines (ATG) regarding IE antibiotic prophylaxis in VHD. Most (92.7%) were unaware of the rheumatic heart disease (RHD) control program. Nearly all participants indicated prophylaxis for clearly invasive procedures such as tooth extraction (100.0%) and periodontal surgery (95.1%). Many dentists made the decision to prescribe antibiotics themselves (36.6%).

CONCLUSIONS

The majority of dentists followed the ATG's IE prophylaxis recommendations for cardiac lesions and dental procedures. There was limited knowledge of the national RHD guidelines and the WA RHD control program.

Can non-fatal burden estimates from the Global Burden of Disease study be used locally? An investigation using models of stroke and diabetes for South Africa

Background: The Global Burden of Disease (GBD) approach estimates disease burden by combining fatal (years of life lost) and non-fatal burden prevalence-based years of life lived with disability (PYLDs) estimates. Although South Africa has data to estimate mortality, prevalence data to estimate non-fatal burden are sparse. PYLD estimates from the GBD study for South Africa can potentially be used. However, there is a divergence in mortality estimates for South Africa between the second South African National Burden of Disease (SANBD2) and 2013 GBD studies. Objective: We investigated the feasibility of utilising GBD PYLD estimates for stroke and diabetes by exploring different disease modelling scenarios. Method: DisMod II software-generated South African stroke and diabetes PYLDs for 2010 from models using local epidemiological parameters and demographic data for people 20-79 years old. We investigated the impact on PYLD estimates of 1) differences in the cause-of-death envelope, 2) differences in the cause-specific mortality estimates (increase/decrease by 15% for stroke and 30% for diabetes), and 3) difference using local disease parameters compared to other country or region parameters. Differences were expressed as ratios, average ratios and ratio ranges. Results: Using the GBD cause-of-death envelope (16% more deaths than SANBD2) and holding other parameters constant yielded age-specific ratios of PYLDs for stroke and diabetes ranging between 0.89 and 1.07 (average 0.98) for males. Similar results were observed for females. A 15% change in age-specific stroke mortality showed little difference in the ratio comparison of PYLDs (range 0.98-1.02) while a 30% change in age-specific diabetes mortality resulted in a ratio range of 0.96-1.07 for PYLDs depending on age. Conclusion: This study showed that GBD non-fatal burden estimates (PYLDs) can be used for stroke and diabetes non-fatal burden in the SANBD2 study.

Ending rheumatic heart disease in Australia: the evidence for a new approach

■The RHD Endgame Strategy: the blueprint to eliminate rheumatic heart disease in Australia by 2031 (the Endgame Strategy) is the blueprint to eliminate rheumatic heart disease (RHD) in Australia by 2031. Aboriginal and Torres Strait Islander people live with one of the highest per capita burdens of RHD in the world. ■The Endgame Strategy synthesises information compiled across the 5-year lifespan of the End Rheumatic Heart Disease Centre of Research Excellence (END RHD CRE). Data and results from priority research projects across several disciplines of research complemented literature reviews, systematic reviews and narrative reviews. Further, the experiences of those working in acute rheumatic fever (ARF) and RHD control and those living with RHD to provide the technical evidence for eliminating RHD in Australia were included. ■The lived experience of RHD is a critical factor in health outcomes. All future strategies to address ARF and RHD must prioritise Aboriginal and Torres Strait Islander people's knowledge, perspectives and experiences and develop co-designed approaches to RHD elimination. The environmental, economic, social and political context of RHD in Australia is inexorably linked to ending the disease. ■Statistical modelling undertaken in 2019 looked at the economic and health impacts of implementing an indicative strategy to eliminate RHD by 2031. Beginning in 2019, the strategy would include: reducing household crowding, improving hygiene infrastructure, strengthening primary health care and improving secondary prophylaxis. It was estimated that the strategy would prevent 663 deaths and save the health care system $188 million. ■The Endgame Strategy provides the evidence for a new approach to RHD elimination. It proposes an implementation framework of five priority action areas. These focus on strategies to prevent new cases of ARF and RHD early in the causal pathway from Streptococcus pyogenes exposure to ARF, and strategies that address the critical systems and structural changes needed to support a comprehensive RHD elimination strategy.

The use of cardiac valve procedures for rheumatic heart disease in Australia; a cross-sectional study 2002-2017

Background

Australia, although a high income economy, carries a significant burden of rheumatic heart disease (RHD). Acute rheumatic fever (ARF) and RHD are endemic in the Indigenous population. Immigrants from low/lower-income countries (‘non-Indigenous high-risk’) are also at increased risk compared with ‘non-Indigenous low-risk’ Australians. This study describes the utilisation of surgical and percutaneous procedures for RHD-related valve disease among patients aged less than 50 years, from 2002 to 2017.

Methods

A descriptive study using data from the ‘End RHD in Australia: Study of Epidemiology (ERASE) Project’ linking RHD Registers and hospital inpatient data from five states/territories, and two surgical databases. Trends across three-year periods were determined and post-procedural all-cause 30-day mortality calculated.

Results

A total of 3900 valves interventions were undertaken in 3028 procedural episodes among 2487 patients. Over 50% of patients were in the 35–49 years group, and 64% were female. Over 60% of procedures for 3-24 year-olds were for Indigenous patients. There were few significant changes across the study period other than downward trends in the number and proportion of procedures for young Indigenous patients (3–24 years) and ‘non-Indigenous/low risk’ patients aged ≥35 years. Mitral valve procedures predominated, and multi-valve interventions increased, including on the tricuspid valve. The majority of replacement prostheses were mechanical, although bioprosthetic valve use increased overall, being highest among females <35 years and Indigenous Australians. All-cause mortality (n = 42) at 30-days was 1.4% overall (range 1.1–1.7), but 2.0% for Indigenous patients.

Conclusions

The frequency of cardiac valve procedures, and 30-day mortality remained steady across 15 years. Some changes in the distribution of procedures in population groups were evident. Replacement procedures, the use of bioprosthetic valves, and multiple-valve interventions increased. The challenge for Australian public health officials is to reduce the incidence, and improve the early detection and management of ARF/RHD in high-risk populations within Australia.

•

Epidemic RHD in Indigenous Australians drives RHD-related cardiac valve procedures.

•

30-day mortality post-procedural is low in those under 50 years.

•

Bioprosthetic valve replacements higher in young women, and increasing in older patients.

Contemporary Incidence and Prevalence of Rheumatic Fever and Rheumatic Heart Disease in Australia Using Linked Data: The Case for Policy Change

Background In 2018, the World Health Organization prioritized control of acute rheumatic fever (ARF) and rheumatic heart disease (RHD), including disease surveillance. We developed strategies for estimating contemporary ARF/RHD incidence and prevalence in Australia (2015-2017) by age group, sex, and region for Indigenous and non-Indigenous Australians based on innovative, direct methods. Methods and Results This population-based study used linked administrative data from 5 Australian jurisdictions. A cohort of ARF (age <45 years) and RHD cases (<55 years) were sourced from jurisdictional ARF/RHD registers, surgical registries, and inpatient data. We developed robust methods for epidemiologic case ascertainment for ARF/RHD. We calculated age-specific and age-standardized incidence and prevalence. Age-standardized rate and prevalence ratios compared disease burden between demographic subgroups. Of 1425 ARF episodes, 72.1% were first-ever, 88.8% in Indigenous people and 78.6% were aged <25 years. The age-standardized ARF first-ever rates were 71.9 and 0.60/100 000 for Indigenous and non-Indigenous populations, respectively (age-standardized rate ratio=124.1; 95% CI, 105.2-146.3). The 2017 Global Burden of Disease RHD prevalent counts for Australia (<55 years) underestimate the burden (1518 versus 6156 Australia-wide extrapolated from our study). The Indigenous age-standardized RHD prevalence (666.3/100 000) was 61.4 times higher (95% CI, 59.3-63.5) than non-Indigenous (10.9/100 000). Female RHD prevalence was double that in males. Regions in northern Australia had the highest rates. Conclusions This study provides the most accurate estimates to date of Australian ARF and RHD rates. The high Indigenous burden necessitates urgent government action. Findings suggest RHD may be underestimated in many high-resource settings. The linked data methods outlined here have potential for global applicability.

Hospital Presentations in Long-Term Survivors of Stroke: Causes and Associated Factors in a Linked Data Study

BACKGROUND AND PURPOSE

A comprehensive understanding of the long-term impact of stroke assists in health care planning. We aimed to determine changes in rates, causes, and associated factors for hospital presentations among long-term survivors of stroke.

METHODS

Person-level data from the AuSCR (Australian Stroke Clinical Registry) during 2009 to 2013 were linked with state-based health department emergency department and hospital admission data. The study cohort included adults with first-ever stroke who survived the first 6 months after discharge from hospital. Annualized rates of hospital presentations (nonadmitted emergency department or admission)/person/year were calculated for 1 to 12 months prior, and 7 to 12 months (inclusive) after hospitalization. Multilevel, negative binomial regression was used to identify associated factors after adjustment for prestroke hospital presentations and stratification for perceived impairment status. Perceived impairments to health were defined according to the subscales and visual analog health status scores on the 5-Dimension European Quality of Life Scale.

RESULTS

There were 7183 adults with acute stroke, 7-month survivors (median age 72 years; 56% male; 81% ischemic, and 42% with impairment at 90-180 days) from 39 hospitals included in this landmark analysis. Annualized presentations/person increased from 0.88 (95% CI, 0.86-0.91) to 1.25 (95% CI, 1.22-1.29) between the prestroke and poststroke periods, with greater rate increases in those with than without perceived impairment (55% versus 26%). Higher presentation rates were most strongly associated with older age (≥85 versus 65 years, incidence rate ratio, 1.52 [95% CI, 1.27-1.82]) and greater comorbidity score (incidence rate ratio, 1.06 [95% CI, 1.02-1.10]), whereas reduced rates were associated with greater social advantage (incidence rate ratio, 0.71 [95% CI, 0.60-0.84]). Poststroke hospital presentations (7-12 months) were most frequently related to recurrent cardiovascular and cerebrovascular events and sequelae of stroke.

CONCLUSIONS

A large increase in annualized hospital presentation rates after stroke indicates the potential for improved community management and support for this vulnerable patient group.

Case Ascertainment on Australian Registers for Acute Rheumatic Fever and Rheumatic Heart Disease

In Australia, disease registers for acute rheumatic fever (ARF) and rheumatic heart disease (RHD) were previously established to facilitate disease surveillance and control, yet little is known about the extent of case-ascertainment. We compared ARF/RHD case ascertainment based on Australian ARF/RHD register records with administrative hospital data from the Northern Territory (NT), South Australia (SA), Queensland (QLD) and Western Australia (WA) for cases 3-59 years of age. Agreement across data sources was compared for persons with an ARF episode or first-ever RHD diagnosis. ARF/RHD registers from the different jurisdictions were missing 26% of Indigenous hospitalised ARF/RHD cases overall (ranging 17-40% by jurisdiction) and 10% of non-Indigenous hospitalised ARF/RHD cases (3-28%). The proportion of hospitalised RHD cases (36%) was half the proportion of hospitalised ARF cases (70%) notified to the ARF/RHD registers. The registers were found to capture few RHD cases in metropolitan areas (SA Metro: 13%, QLD Metro: 35%, WA Metro: 14%). Indigenous status, older age, comorbidities, drug/alcohol abuse and disease severity were predictors of cases appearing in the hospital data only (p < 0.05); sex was not a determinant. This analysis confirms that there are biases associated with the epidemiological analysis of single sources of case ascertainment for ARF/RHD using Australian data.

Development and Evaluation of a Prediction Model for Ascertaining Rheumatic Heart Disease Status in Administrative Data

Background

Previous research has raised substantial concerns regarding the validity of the International Statistical Classification of Diseases and Related Health Problems (ICD) codes (ICD-10 I05-I09) for rheumatic heart disease (RHD) due to likely misclassification of non-rheumatic valvular disease (non-rheumatic VHD) as RHD. There is currently no validated, quantitative approach for reliable case ascertainment of RHD in administrative hospital data.

Methods

A comprehensive dataset of validated Australian RHD cases was compiled and linked to inpatient hospital records with an RHD ICD code (2000-2018, n=7555). A prediction model was developed based on a generalized linear mixed model structure considering an extensive range of demographic and clinical variables. It was validated internally using randomly selected cross-validation samples and externally. Conditional optimal probability cutpoints were calculated, maximising discrimination separately for high-risk versus low-risk populations.

Results

The proposed model reduced the false-positive rate (FPR) from acute rheumatic fever (ARF) cases misclassified as RHD from 0.59 to 0.27; similarly for non-rheumatic VHD from 0.77 to 0.22. Overall, the model achieved strong discriminant capacity (AUC: 0.93) and maintained a similar robust performance during external validation (AUC: 0.88). It can also be used when only basic demographic and diagnosis data are available.

Conclusion

This paper is the first to show that not only misclassification of non-rheumatic VHD but also of ARF as RHD yields substantial FPRs. Both sources of bias can be successfully addressed with the proposed model which provides an effective solution for reliable RHD case ascertainment from hospital data for epidemiological disease monitoring and policy evaluation.

Priorities for improved management of acute rheumatic fever and rheumatic heart disease: analysis of cross-sectional continuous quality improvement data in Aboriginal primary healthcare centres in Australia

Objective This study investigated the delivery of guideline-recommended services for the management of acute rheumatic fever (ARF) and rheumatic heart disease (RHD) in Australian primary healthcare centres participating in the Audit and Best Practice for Chronic Disease (ABCD) National Research Partnership project. Methods ARF and RHD clinical audit data were collected from 63 Aboriginal centres in four Australian jurisdictions using the ABCD ARF/RHD audit tool. Records of up to 30 patients treated for ARF and/or RHD were analysed per centre from the most recent audit conducted between 2009 and 2014. The main outcome measure was a quality of ARF and RHD care composite indicator consisting of nine best-practice service items. Results Of 1081 patients, most were Indigenous (96%), female (61%), from the Northern Territory and Queensland (97%) and <25 years of age (49%). The composite indicator was highest in the 0-14 year age group (77% vs 65-67% in other age groups). Timely injections and provision of client education are important specific areas for improvement. Multiple regression showed age >15 years to be a significant negative factor for several care indicators, particularly for the delivery of long-acting antibiotic injections and specialist services in the 15-24 year age group. Conclusions The results suggest that timely injection and patient education are priorities for managing ARF and RHD, particularly focusing on child-to-adult transition care. What is known about the topic? The burden of rheumatic fever and RHD in some Aboriginal communities is among the highest documented globally. Guideline-adherent RHD prevention and management in primary health care (PHC) settings are critically important to reduce this burden. Continuous quality improvement (CQI) is a proven strategy to improve guideline adherence, using audit cycles and proactive engagement of PHC end users with their own data. Previously, such CQI strategies using a systems approach were shown to improve delivery of ARF and RHD care in six Aboriginal health services (three government and three community controlled). What does this paper add? This paper focuses on the variation across age groups in the quality of ARF and/or RHD care according to nine quality of care indicators across 63 PHC centres serving the Aboriginal population in the Northern Territory, Queensland, South Australia and Western Australia. These new findings provide insight into difference in quality of care by life stage, indicating particular areas for improvement of the management of ARF and RHD at the PHC level, and can act as a baseline for monitoring of care quality for ARF and RHD into the future. What are the implications for practitioners? Management plans and innovative strategies or systems for improving adherence need to be developed as a matter of urgency. PHC professionals need to closely monitor adherence to secondary prophylaxis at both the clinic and individual level. RHD priority status needs to be assigned and recorded as a tool to guide management. Systems strengthening needs to particularly target child-to-adult transition care. Practitioners are urged to keep a quick link to the RHDAustralia website to access resources and guidelines pertaining to ARF and RHD (https://www.rhdaustralia.org.au/arf-rhd-guideline, accessed 3 October 2019). CQI strategies can assist PHC centres to improve the care they provide to patients.

Collaborative data familiarisation and quality assessment: Reflections from use of a national dataset to investigate palliative care for Indigenous Australians

BACKGROUND

Data quality is fundamental to the integrity of quantitative research. The role of external researchers in data quality assessment (DQA) remains ill-defined in the context of secondary use for research of large, centrally curated health datasets. In order to investigate equity of palliative care provided to Indigenous Australian patients, researchers accessed a now-historical version of a national palliative care dataset developed primarily for the purpose of continuous quality improvement.

OBJECTIVES

(i) To apply a generic DQA framework to the dataset and (ii) to report the process and results of this assessment and examine the consequences for conducting the research.

METHOD

The data were systematically examined for completeness, consistency and credibility. Data quality issues relevant to the Indigenous identifier and framing of research questions were of particular interest.

RESULTS

The dataset comprised 477,518 records of 144,951 patients (Indigenous N = 1515; missing Indigenous identifier N = 4998) collected from participating specialist palliative care services during a period (1 January 2010-30 June 2015) in which data-checking systems underwent substantial upgrades. Progressive improvement in completeness of data over the study period was evident. The data were error-free with respect to many credibility and consistency checks, with anomalies detected reported to data managers. As the proportion of missing values remained substantial for some clinical care variables, multiple imputation procedures were used in subsequent analyses.

CONCLUSION AND IMPLICATIONS

In secondary use of large curated datasets, DQA by external researchers may both influence proposed analytical methods and contribute to improvement of data curation processes through feedback to data managers.

Low positive predictive value of International Classification of Diseases, 10th Revision codes in relation to rheumatic heart disease: a challenge for global surveillance

International Classification of Diseases, 10th Revision codes for rheumatic heart disease (RHD) include valvular heart disease of unspecified origin, limiting their usefulness for estimating RHD burden. A cross-disciplinary national consultation developed an algorithm to improve RHD identification in hospital data. The algorithm has been operationalised and piloted. The algorithm developed categorised 32% of RHD-coded patients as probable/possible RHD. We outline a series of research initiatives to improve identification of RHD in administrative data thereby contributing to monitoring the RHD burden globally.

Disparities in Antihypertensive Prescribing After Stroke

Background and Purpose—

Despite evidence to support the prescription of antihypertensive medications before hospital discharge to promote medication adherence and prevent recurrent events, many patients with stroke miss out on these medications at discharge. We aimed to examine patient, clinical, and system-level differences in the prescription of antihypertensive medications at hospital discharge after stroke.

Methods—

Adults with acute ischemic stroke or intracerebral hemorrhage alive at discharge were included (years 2009–2013) from 39 hospitals participating in the Australian Stroke Clinical Registry. Patient comorbidities were identified using the International Statistical Classification of Diseases and Related Health Problems (Tenth Edition, Australian Modification ) codes from the hospital admissions and emergency presentation data. The outcome variable and other system factors were derived from the Australian Stroke Clinical Registry dataset. Multivariable, multilevel logistic regression was used to examine factors associated with the prescription of antihypertensive medications at hospital discharge.

Results—

Of the 10 315 patients included, 79.0% (intracerebral hemorrhage, 74.1%; acute ischemic stroke, 79.8%) were prescribed antihypertensive medications at discharge. Prescription varied between hospital sites, with 6 sites >2 SDs below the national average for provision of antihypertensives at discharge. Prescription was also independently associated with patient and clinical factors including history of hypertension, diabetes mellitus, management in an acute stroke unit, and discharge to rehabilitation. In patients with acute ischemic stroke, females (odds ratio, 0.85; 95% CI, 0.76–0.94), those who had greater stroke severity (odds ratio, 0.81; 95% CI 0.72–0.92), or dementia (odds ratio, 0.65; 95% CI, 0.52–0.81) were less likely to be prescribed.

Conclusions—

Prescription of antihypertensive medications poststroke varies between hospitals and according to patient factors including age, sex, stroke severity, and comorbidity profile. Implementation of targeted quality improvement initiatives at local hospitals may help to reduce the variation in prescription observed.

Rheumatic heart disease in pregnancy: Profile of women admitted to a Western Australian tertiary obstetric hospital

This retrospective study assessed maternal and perinatal outcomes for women with rheumatic heart disease (RHD) admitted to the largest tertiary obstetric hospital in Western Australia from 2009 to 2016. Of 54 women identified, 75.9% were Indigenous, 59.3% lived in rural areas and 40.7% had severe RHD. Heart failure developed in 10% who gave birth. Indigenous women were younger, had higher gravidity (P = 0.0305), were more likely to receive secondary prophylaxis (P = 0.0041) and have sub-optimal antenatal clinic attendance (P = 0.0078). There were no maternal deaths and two perinatal deaths (4.0%), reflecting vigilance in the obstetric management of women with RHD in Western Australia.

The End Rheumatic Heart Disease in Australia Study of Epidemiology (ERASE) Project: data sources, case ascertainment and cohort profile

PURPOSE

Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) persist as public health issues in developing countries and among disadvantaged communities in high-income countries, with rates in Aboriginal and Torres Strait Islander peoples in Australia among the highest recorded globally. A robust evidence base is critical to support policy recommendations for eliminating RHD, but available data are fragmented and incomplete. The End RHD in Australia: Study of Epidemiology (ERASE) Project aims to provide a comprehensive database of ARF and RHD cases in Australia as a basis for improved monitoring and to assess prevention and treatment strategies. The objective of this paper is to describe the process for case ascertainment and profile of the study cohort.

PATIENTS AND METHODS

The ERASE database has been built using linked administrative data from RHD registers, inpatient hospitalizations, and death registry data from 2001 to 2017 (mid-year). Additional linked datasets are available. The longitudinal nature of the data is harnessed to estimate onset and assess the progression of the disease. To accommodate systematic limitations in diagnostic coding for RHD, hospital-only identified RHD has been determined using a purposefully developed prediction model.

RESULTS

Of 132,053 patients for whom data were received, 42,064 are considered true cases of ARF or RHD in the study period. The patient population under 60 years in the compiled dataset is more than double the number of patients identified in ARF/RHD registers (12,907 versus 5049). Non-registered patients were more likely to be older, non-Indigenous, and at a later disease stage.

CONCLUSION

The ERASE Project has created an unprecedented linked administrative database on ARF and RHD in Australia. These data provide a critical baseline for efforts to end ARF/RHD in Australia. The methodological work conducted to compile this database resulted in significant improvements in the robustness of epidemiological estimates and entails valuable lessons for ARF/RHD research globally.

Delay in commencement of palliative care service episodes provided to Indigenous and non-Indigenous patients: cross-sectional analysis of an Australian multi-jurisdictional dataset

Background

Rapid effective responsiveness to patient needs is pivotal to high quality palliative care. Aboriginal and Torres Strait Islander (Indigenous) people are susceptible to life-limiting illnesses at younger ages than other Australians and experience inequity of health service provision. The Palliative Care Outcomes Collaboration collects Australia-wide health service data on patient care, and has established performance benchmarks for specialist palliative care services. We investigated whether the benchmark for timely commencement of palliative care episodes (occurrence of delay >1 day after being designated ‘ready for care’ in <10% instances) is being met for Indigenous Australians in participating services. Additionally, we investigated the association between identification as Indigenous and delay.

Methods

Using multi-jurisdictional Palliative Care Outcomes Collaboration data, this cross-sectional analytical study investigated all episodes of care (n = 84,238) provided to patients ≥18 years (n = 61,073: Indigenous n = 645) in hospital and community settings commenced and completed during the period 01/07/2013–30/06/2015. Proportions of episodes resulting in delay were determined. Crude and adjusted odds of delay among Indigenous compared with non-Indigenous patients were investigated using multiple logistic regression, with missing data handled by multiple imputation.

Results

The benchmark was met for both Indigenous and non-Indigenous patients (delay in 8.3 and 8.4% episodes respectively). However, the likelihood of delay was modestly higher in episodes provided to Indigenous than non-Indigenous patients (adjusted odds ratio [aOR], 1.41; 95% confidence interval [CI] 1.07–1.86). Excess delay among Indigenous patients was accentuated in first episodes (aOR, 1.53; 95% CI 1.14–2.06), in patients aged < 65 years (aOR, 1.66; 95% CI 1.14–2.41), and among those residing in Inner Regional areas (aOR, 1.97; 95% CI 1.19–3.28), and also approached significance among those in outer regional, remote and very remote areas collectively (aOR, 1.72; CI 0.97–3.05).

Conclusions

Although the timeliness benchmark is being met for Indigenous Australians in palliative care, they may experience delayed initiation of care episodes, particularly if younger, and especially at first encounter with a service. Qualitative research is required to explore determinants of delay in initiating palliative care episodes. The timeliness of initial referral for specialist palliative care in this population remains to be determined.

Electronic supplementary material

The online version of this article (10.1186/s12904-018-0380-7) contains supplementary material, which is available to authorized users.

Complexity in disease management: A linked data analysis of multimorbidity in Aboriginal and non-Aboriginal patients hospitalised with atherothrombotic disease in Western Australia

BACKGROUND

Hospitalisation for atherothrombotic disease (ATD) is expected to rise in coming decades. However, increasingly, associated comorbidities impose challenges in managing patients and deciding appropriate secondary prevention. We investigated the prevalence and pattern of multimorbidity (presence of two or more chronic conditions) in Aboriginal and non-Aboriginal Western Australian residents with ATDs.

METHODS AND FINDINGS

We used population-based de-identified linked administrative health data from 1 January 2000 to 30 June 2014 to identify a cohort of patients aged 25-59 years admitted to Western Australian hospitals with a discharge diagnosis of ATD. The prevalence of common chronic diseases in these patients was estimated and the patterns of comorbidities and multimorbidities empirically explored using two different approaches: identification of the most commonly occurring pairs and triplets of comorbid diseases, and through latent class analysis (LCA). Half of the cohort had multimorbidity, although this was much higher in Aboriginal people (Aboriginal: 79.2% vs. non-Aboriginal: 39.3%). Only a quarter were without any documented comorbidities. Hypertension, diabetes, alcohol abuse disorders and acid peptic diseases were the leading comorbidities in the major comorbid combinations across both Aboriginal and non-Aboriginal cohorts. The LCA identified four and six distinct clinically meaningful classes of multimorbidity for Aboriginal and non-Aboriginal patients, respectively. Out of the six groups in non-Aboriginal patients, four were similar to the groups identified in Aboriginal patients. The largest proportion of patients (33% in Aboriginal and 66% in non-Aboriginal) was assigned to the "minimally diseased" (or relatively healthy) group, with most patients having less than two conditions. Other groups showed variability in degree and pattern of multimorbidity.

CONCLUSION

Multimorbidity is common in ATD patients and the comorbidities tend to interact and cluster together. Physicians need to consider these in their clinical practice. Different treatment and secondary prevention strategies are likely to be useful for management in these cluster groups.

Patterns of Medicare-funded primary health and specialist consultations in Aboriginal and non-Aboriginal Australians in the two years before hospitalisation for ischaemic heart disease

BACKGROUND

Ischaemic heart disease (IHD) remains the leading cause of morbidity and mortality for both Aboriginal and non-Aboriginal Australians. Patterns of primary and specialist care in patients leading up to the first hospitalisation for IHD potentially impact on prevention and subsequent outcomes. We investigated the differences in general practice (GP), specialist and emergency department (ED) consultations, and associated resource use in Aboriginal and non-Aboriginal people in the two years preceding hospitalisation for IHD.

METHODS

Linked-data were used to identify first IHD admissions for Western Australians aged 25-74 years in 2002-2007. Person-linked GP, specialist and ED consultations were obtained from the Medicare Benefits Schedule (MBS) and ED records to assess health care access and costs for the preceding 2 years.

RESULTS

Aboriginal people constituted 4.7% of 27,230 IHD patients, 3.5% of 1,348,238 MBS records, and 14% of 33,170 ED presentations. Aboriginal (vs. non-Aboriginal) people were younger (mean 50.2 vs 60.5 years), more commonly women (45.2% vs 28.4%), had more comorbidities [Charlson index≥1, 35.2% vs 26.3%], were more likely to have had GP visits (adjusted rate-ratio 1.07, 95% CI 1.02-1.12), long/prolonged (16.0% vs 11.9%) consults and non-vocationally registered GP consults (17.1% vs 3.2%), but less likely to received specialist consults (mean 1.0 vs 4.1). Mean number of urgent/semi-urgent ED presentations in the year preceding the IHD admission was higher in Aboriginal people (2.9 vs 1.9). Aboriginal people incurred 2.7% of total associated MBS expenditure (estimated at $59.7 million). Mean total cost per person was 43.3% lower in Aboriginal patients, with cost differentials being greatest in diabetic and chronic kidney disease patients.

CONCLUSIONS

Despite being over-represented in urgent/semi-urgent ED presentations and admissions for IHD, Aboriginal people were under-resourced compared with the rest of the population, particularly in terms of specialist care prior to first IHD hospitalisation. The findings underscore the need for better primary and specialist shared care delivery models particularly for Aboriginal people.

Rheumatic heart disease: infectious disease origin, chronic care approach

BACKGROUND

Rheumatic heart disease (RHD) is a chronic cardiac condition with an infectious aetiology, causing high disease burden in low-income settings. Affected individuals are young and associated morbidity is high. However, RHD is relatively neglected due to the populations involved and its lower incidence relative to other heart diseases.

METHODS AND RESULTS

In this narrative review, we describe how RHD care can be informed by and integrated with models of care developed for priority non-communicable diseases (coronary heart disease), and high-burden communicable diseases (tuberculosis). Examining the four-level prevention model (primordial through tertiary prevention) suggests primordial and primary prevention of RHD can leverage off existing tuberculosis control efforts, given shared risk factors. Successes in coronary heart disease control provide inspiration for similarly bold initiatives for RHD. Further, we illustrate how the Chronic Care Model (CCM), developed for use in non-communicable diseases, offers a relevant framework to approach RHD care. Systems strengthening through greater integration of services can improve RHD programs.

CONCLUSION

Strengthening of systems through integration/linkages with other well-performing and resourced services in conjunction with policies to adopt the CCM framework for the secondary and tertiary prevention of RHD in settings with limited resources, has the potential to significantly reduce the burden of RHD globally. More research is required to provide evidence-based recommendations for policy and service design.

Perspectives of Aboriginal women on participation in mammographic screening: a step towards improving services

Background

Early detection of breast cancer using screening mammography provides an opportunity for treatment which can lead to significantly improved outcomes. Despite considerable efforts having been made, the rate at which Aboriginal and Torres Strait Islander (hereafter respectfully referred to as Aboriginal) women in Western Australia participate in BreastScreen WA’s screening mammogram program remains below that for the overall female population of Western Australia. This study aimed to examine perspectives on breast screening amongst Aboriginal women in Western Australia. We explored the factors which impact on participation in breast screening and sought to identify potential initiatives to address lower participation in screening.

Methods

Semi-structured interviews, focus group discussions and yarning sessions were conducted with a total of 65 research participants. They were all Aboriginal and comprised consumers and health professionals from locations across the state.

Results

Our findings show that research participants generally were willing to have a mammogram. Key reasons given were having a genetic predisposition to breast cancer and a perception of investing in health for the sake of the next generation, as well as personal well-being. Barriers identified included lack of education about or understanding of screening, inadequacies in cultural appropriateness in the screening program, cultural beliefs around cancer in general and breast cancer in particular, and competing health and life priorities. However, many enablers were identified which can serve as potential strategies to assuage fear and increase screening uptake. These included increased education delivered by respected Aboriginal women, culturally appropriate promotion and the provision of care and support from other women in the community.

Conclusion

The higher participation rates for Aboriginal women in Western Australia than are found for Aboriginal women nationally demonstrate the success of the strategies put in place by BreastScreen WA. These efforts must be supported and existing policies and practices enhanced to address the limitations in the existing program. Only by implementing and evaluating such initiatives and making breast screening programs more accessible to Aboriginal women can the current disparity between the screening participation rates of Aboriginal and non-Aboriginal women be reduced.

Secondary preventive medication use in a prevalent population-based cohort of acute coronary syndrome survivors

AIM

Describe the dispensing patterns for guideline-recommended medications during 2008 in people with acute coronary syndrome (ACS) and how dispensing varies by gender and time since last ACS hospitalization.

METHOD

A descriptive cohort spanning 20 years of people alive post-ACS in 2008. We extracted all ACS hospitalizations and deaths in Western Australia (1989-2008), and all person-linked Pharmaceutical Benefits Scheme claims nationally for 2008. Participants were 23 642 men and women (36.8%), alive and aged 65-89 years in mid-2008 who were hospitalized for ACS between 1989 and 2008. Main outcome was the proportion of the study cohort (in 2008) dispensed guideline-recommended cardiovascular medications in that year. Adjusted odds ratios estimating the association between type (and number) of guideline-recommended medications and time since last ACS hospitalization.

RESULTS

Medications most commonly dispensed in 2008 were statins (79.6% of study cohort) and then angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers (ACEi/ARBs) (71.1%), aspirin or clopidogrel (59.4%), and β-blockers (54.6%). Only 51.8% of the cohort was dispensed three or more of these drug types in 2008. Women with ACS were 18% less likely to be dispensed statins (adjusted odds ratio (OR)=0.82; 95% CI 0.76-0.88). Overall, for each incremental year since last ACS admission, there was an 8% increased odds (adjusted OR=1.08; 95% CI 1.07-1.08) of being dispensed fewer of the recommended drug regimen in 2008.

CONCLUSION

Longer time since last ACS admission was associated with dispensing fewer medications types and combinations in 2008. Interventions are warranted to improve dispensing long term and any apparent gender inequality in the drug class filled.

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.

Knowledge translation lessons from an audit of Aboriginal Australians with acute coronary syndrome presenting to a regional hospital

Objective:

Translation of evidence into practice by health systems can be slow and incomplete and may disproportionately impact disadvantaged populations. Coronary heart disease is the leading cause of death among Aboriginal Australians. Timely access to effective medical care for acute coronary syndrome substantially improves survival. A quality-of-care audit conducted at a regional Western Australian hospital in 2011–2012 compared the Emergency Department management of Aboriginal and non-Aboriginal acute coronary syndrome patients. This audit is used as a case study of translating knowledge processes in order to identify the factors that support equity-oriented knowledge translation.

Methods:

In-depth interviews were conducted with a purposive sample of the audit team and further key stakeholders with interest/experience in knowledge translation in the context of Aboriginal health. Interviews were analysed for alignment of the knowledge translation process with the thematic steps outlined in Tugwell’s cascade for equity-oriented knowledge translation framework.

Results:

In preparing the audit, groundwork helped shape management support to ensure receptivity to targeting Aboriginal cardiovascular outcomes. Reporting of audit findings and resulting advocacy were undertaken by the audit team with awareness of the institutional hierarchy, appropriate timing, personal relationships and recognising the importance of tailoring messages to specific audiences. These strategies were also acknowledged as important in the key stakeholder interviews. A follow-up audit documented a general improvement in treatment guideline adherence and a reduction in treatment inequalities for Aboriginal presentations.

Conclusion:

As well as identifying outcomes such as practice changes, a useful evaluation increases understanding of why and how an intervention worked. Case studies such as this enrich our understanding of the complex human factors, including individual attributes, experiences and relationships and systemic factors that shape equity-oriented knowledge translation. Given the potential that improving knowledge translation has to close the gap in Aboriginal health disparities, we must choose strategies that adequately take into account the unique contingencies of context across institutions and cultures.