Informing the prevention, diagnosis and management of acute rheumatic fever and rheumatic heart disease in Aboriginal Australian and Torres Strait Islander populations

Rémond, Marc Gerard Wootton (2014) Informing the prevention, diagnosis and management of acute rheumatic fever and rheumatic heart disease in Aboriginal Australian and Torres Strait Islander populations. PhD thesis, James Cook University.

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Abstract

Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) are auto-immune conditions associated with prior exposure to Group A streptococcus (GAS). ARF is an acute condition associated with fever and joint, brain, skin and heart inflammation. RHD is its chronic sequela and is characterised by permanent heart valve damage which can, in turn, lead to heart failure and an increased risk of endocarditis and stroke. To avoid such complications interventions may be required to repair or replace damaged valves.

ARF and RHD are preventable diseases rarely encountered in mainstream Australia. However, Aboriginal Australian and Torres Strait Islander peoples have amongst the highest reported rates of ARF/RHD in the world with significant morbidity and mortality.

This thesis comprises complementary projects and articles that can inform the community and health service response to prevention, diagnosis and management of ARF/RHD with a particular focus on Indigenous Australians.

Prevention: Three systematic reviews are presented that examine strategies to improve primary and secondary prevention of ARF/RHD. High quality studies are often lacking and much of the evidence informing strategies to prevent ARF/RHD is limited or absent. Available evidence indicates primordial prevention via improvements in social, economic and environmental conditions is key. While primary prevention may be achieved through improved diagnosis and early treatment of GAS pharyngitis, implementation can be difficult and research into the development of a GAS vaccine remains crucial.

Effective secondary prevention of ARF/RHD is possible with long-acting benzathine penicillin (LAB). Nonetheless, delivery of LAB is highly variable and frequently poor. Further work is needed to enhance health care systems to maximize uptake of LAB and to identify more effective formulations or delivery devices for administration.

Diagnosis: The utility of screening for RHD via echocardiography (heart ultrasound) to detect early disease is topical as this may facilitate early administration of secondary prophylaxis thereby limiting disease progression. A review of the feasibility of implementing RHD screening in Australia is presented and a number of limiting factors are highlighted. These include a lack of an agreed case definition and a limited understanding of the significance, natural history and potential treatment of early and subclinical RHD. Further, the delivery of secondary prevention is often suboptimal and the impact of additional cases on health services, and the psychosocial health of patients and families, can be substantial.

The refinement of a screening-based case definition for RHD, and particularly the significance of minor heart valve abnormalities, was informed by the Rheumatic Fever Follow-up Study (RhFFUS). Children with prior Borderline RHD (defined under World Heart Federation (WHF) criteria) were up to nine times more likely to experience ARF compared with children with a normal echocardiogram. Their risk of having progressive valve damage was also significantly greater and 1 in 6 developed Definite RHD. In contrast, children with less severe valve abnormalities not satisfying criteria for Borderline RHD were at no greater risk of ARF or echocardiographic progression of valvular lesions.

These results provide cogent evidence that, in some children, valvular changes consistent with Borderline RHD detected on screening echocardiograms represent the earliest stage of Definite RHD. Such children may benefit from secondary prophylaxis or enhanced surveillance through regular echocardiographic monitoring to assess for progression of disease. Moreover, these results lend support to the validity of WHF criteria that distinguish Borderline RHD from other minor echocardiographic changes, as it is only in the former group that there is a greater risk of ARF and valvular lesion progression. Nonetheless, the fact that individuals with minor echocardiographic changes not satisfying criteria for Borderline RHD still had an increased risk of developing Definite RHD suggests that such individuals should be initially monitored with echocardiography to ensure they do not progress.

Management: The final component of this thesis comprises two papers that describe projects that were undertaken to inform potential improvements in the management of ARF/RHD. The first compared the quality of care provided to patients in the Kimberley and far north Queensland where differing models of care were operating. This highlighted more severe disease in the Kimberley and greater specialist follow-up and prescription and receipt of secondary prophylaxis in far north Queensland. This supported an association between far north Queensland's single-provider model of care and centralised RHD control programme and improved patient care, potentially fewer cases of severe disease, and reduced need for surgical and other interventions. Since this study was completed, a centralized RHD control and management programme has been implemented in the Kimberley.

The second project related to the use of prophylactic antibiotics to prevent bacteremia, and potentially infective endocarditis (IE), in patients with RHD undergoing high-risk procedures. While this is recommended for Indigenous patients with RHD under Australian guidelines, American guidelines were recently amended to recommend prophylaxis only in people with prosthetic valves and not in those with "native-valve" RHD. A review of infective endocarditis cases in northern Australia was undertaken to determine whether native valve RHD was associated with an increased risk of IE. Results of this study showed that those with native valve RHD were at increased risk of IE (RR 58) compared to individuals without native valve RHD. Interestingly, the risk of IE in non-Indigenous patients with RHD was found to be 3.7 times higher than in Indigenous Australians with RHD. This study led to recommendations to broaden current Australian guidelines so as to offer prophylactic antibiotics to all persons with RHD undergoing procedures associated with a high risk of bacteraemia.

In conclusion, this thesis provides a number of new insights to address existing knowledge gaps regarding prevention, diagnosis and management of ARF/RHD. It is hoped that continued work on developing a GAS vaccine will eventually deliver an effective and safe method of primary prevention. In the interim the continued focus on early and accurate diagnosis of ARF/RHD and best-practice management (particularly improving uptake of secondary prophylaxis) should be pursued. Overarching these health initiatives must be a commitment to improving the socioeconomic and environmental status of Aboriginal Australian and Torres Strait Islander peoples living in remote communities as a means of effecting ARF/RHD primordial prevention.

Item ID: 42251
Item Type: Thesis (PhD)
Keywords: Aboriginal Australians; acute rheumatic fever; AFR; Australia; diagnosis; disease prevention; epidemiology; Indigenous Australians; inflammatory disease; management; prevention; RDH; rheumatic heart disease; rheumatology; Torres Strait Islanders
Related URLs:
Additional Information:

Publications arising from this thesis are available from the Related URLs field. The publications are:

Chapter 2: Rémond, Marc, and Maguire, Graeme (2012) Primordial and primary prevention of acute rheumatic fever and rheumatic heart disease. In: Carapetis, Jonathan, Brown, Alex, Maguire, Graeme, Walsh, Warren, Noonan, Sara, and Thompson, Dale, (eds.) The Australian guideline for prevention, diagnosis and management of acute rheumatic fever and rheumatic heart disease. RHD Australia, Darwin, NT, Australia, pp. 19-28.

Chapter 2: Rémond, Marc, and Maguire, Graeme (2011) RHD: Women and pregnancy. O & G Magazine, 13 (3). pp. 47-50.

Chapter 2: Rémond, Marc G.W., Coyle, Meaghan E., Mills, Jane E., and Maguire, Graeme P. (2016) Approaches to improving adherence to secondary prophylaxis for rheumatic fever and rheumatic heart disease: a literature review with a global perspective. Cardiology in Review, 24 (2). pp. 94-98.

Chapter 3: Rémond, Marc Gerard Wootton, Wark, Emma Kathleen, and Maguire, Graeme Paul (2013) Screening for rheumatic heart disease in Aboriginal and Torres Strait Islander children. Journal of Paediatrics and Child Health, 49 (7). pp. 526-531.

Chapter 3: Remond, Marc Gerard Wootton, Atkinson, David, White, Andrew, Hodder, Yvonne, Brown, Alex D.H., Carapetis, Jonathan R., and Maguire, Graeme Paul (2012) Rheumatic Fever Follow-Up Study (RhFFUS) protocol: a cohort study investigating the significance of minor echocardiographic abnormalities in Aboriginal Australian and Torres Strait Islander children. BMC Cardiovascular Disorders, 12 (111). pp. 1-8.

Chapter 3: Rémond, Marc, Atkinson, David, White, Andrew, Brown, Alex, Carapetis, Jonathan, Remenyi, Bo, Roberts, Kathryn, and Maguire, Graeme (2015) Are minor echocardiographic changes associated with an increased risk of acute rheumatic fever or progression to rheumatic heart disease? International Journal of Cardiology, 198. pp. 117-122.

Chapter 4: Remond, M.G.W., Severin, K.L., Hodder, Y., Martin, J., Nelson, C., Atkinson, D., and Maguire, G.P. (2013) Variability in disease burden and management of rheumatic fever and rheumatic heart disease in two regions of tropical Australia. Internal Medicine Journal, 43 (4). pp. 386-393.

Chapter 4: Baskerville, Catherine A., Hanrahan, Brendan B., Burke, Andrew J., Holwell, Anna J., Rémond, Marc G.W., and Maguire, Graeme P. (2012) Infective endocarditis and rheumatic heart disease in the north of Australia. Heart, Lung and Circulation, 21 (1). pp. 36-41.

Appendix 1: Rémond, M.G.W., Wheaton, G.R., Walsh, W.F., Prior, D.L., and Maguire, G.P. (2012) Acute rheumatic fever and rheumatic heart disease — priorities in prevention, diagnosis and management. A report of the CSANZ Indigenous Cardiovascular Health Conference, Alice Springs, 2011. Heart, Lung and Circulation, 21 (10). pp. 632-638.

Date Deposited: 14 Jan 2016 03:01
FoR Codes: 11 MEDICAL AND HEALTH SCIENCES > 1102 Cardiovascular Medicine and Haematology > 110201 Cardiology (incl Cardiovascular Diseases) @ 50%
11 MEDICAL AND HEALTH SCIENCES > 1117 Public Health and Health Services > 111701 Aboriginal and Torres Strait Islander Health @ 50%
SEO Codes: 92 HEALTH > 9201 Clinical Health (Organs, Diseases and Abnormal Conditions) > 920103 Cardiovascular System and Diseases @ 33%
92 HEALTH > 9203 Indigenous Health > 920302 Aboriginal and Torres Strait Islander Health - Health Status and Outcomes @ 33%
92 HEALTH > 9203 Indigenous Health > 920303 Aboriginal and Torres Strait Islander Health - Health System Performance (incl. Effectiveness of Interventions) @ 34%
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