1.06 Acute rheumatic fever and rheumatic heart disease
Why is it important?
Acute rheumatic fever (ARF) is a disease caused by an autoimmune reaction to an infection with the bacterium group A streptococcus (GAS). ARF is a short illness, but can result in permanent damage to the heart—rheumatic heart disease (RHD). A person who has had ARF once is susceptible to repeated episodes, which can increase the risk of RHD. Following an initial diagnosis of ARF, patients require long-term treatment, including long-term antibiotic treatment to avoid further infections that may damage the heart (AIHW 2013g; RHDAustralia 2012). Heart surgery may be required to repair heart valve damage resulting from RHD.
ARF and RHD are associated with environmental factors such as poverty and poor living conditions. ARF and RHD are now rare diseases in populations with good living conditions and easy access to quality medical care (Parnaby et al. 2010). Aboriginal and Torres Strait Islander peoples will remain at risk of ARF/RHD while socio-economic disadvantage and barriers to accessing health care persist.
Rheumatic Heart Disease Control Programme registers have been established in the NT, Qld and WA with SA currently under development. The NT RHD register has been operating in the Top End since 1997 and in Central Australia since 2001 and currently provides the strongest source of dataon ARF and RHD. Comparisons between jurisdictions should not be made because registers are at different stages of coverage and completion. A number of smaller, geographically limited studies have also been conducted.
Acute rheumatic fever
In the period 2010–13, there were 743 new or recurrent cases of ARF in the NT, WA and Qld combined. The majority (approximately 94%) were for Aboriginal and Torres Strait Islander peoples. ARF is largely restricted to older children and young adults: among Aboriginal and Torres Strait Islander peoples, 52% of cases occurred in children aged 5–14 years, with a further 27% in the 15–24 years age group. Recorded rates of ARF for Indigenous Australians were 1.2 per 1,000 in the NT, 0.6 per 1,000 in WA and 0.3 per 1,000 in Qld. In the NT, the rate has nearly doubled between 2006 and 2013, although this change is not statistically significant.
ARF is not exclusively a disease associated with remote areas. A small study of 26 hospitalisations for ARF to a paediatric hospital in Sydney between 2000 and 2008 found that the majority of these cases were Pacific Islander and Aboriginal and Torres Strait Islander children from suburban Sydney. The authors found that 69% of the children with this disease were from families in the 2 most disadvantaged quintiles of socio-economic advantage/ disadvantage. Additionally, barriers to timely diagnosis were identified in 81% of children, including delayed presentation and delayed referral (Smith et al. 2011).
Rheumatic heart disease
In December 2013, there were 1,474 Aboriginal and Torres Strait Islander people recorded as having RHD in the NT, and 305 in WA. The corresponding figure for Qld was 921 as at July 2014. The prevalence rate of RHD in Indigenous Australians was 20.6 per 1,000 in the NT, 4.5 per 1,000 in Qld and 3.3 per 1,000 in WA. Females comprised 65% of Indigenous Australians in the NT with RHD. After adjusting for differing population age structures, the prevalence of RHD was 39 times as high among Indigenous Australians as it was among other residents of the NT and 206 times higher for Indigenous Australians in Queensland. Data for other Australians is not currently available from the WA register.
Between 2006 and 2013 there was a 41% decline in new registrations of RHD among Indigenous Australians in the NT. There was an increase in new registrations of RHD in WA between 2010 and 2013 though this is likely to be at least in part due to an increase in improved diagnosis and registration.
A recent audit of control programmes in far North Queensland and the Kimberley region of WA found that 1 in 5 patients with RHD had been prescribed an anti-coagulant, 55% had received a specialist review within recommended timeframes, 61% had a timely echocardiogram and 22% had undergone valve surgery. Of patients who were recommended benzathine penicillin secondary prophylaxis, only 18% received more than 80% of scheduled doses in the 12 months prior (Rémond et al. 2013).
Indigenous Australians were hospitalised for ARF/RHD at rates of around 7 times that of other Australians (0.6 per 1,000 compared with 0.1 per 1,000 for non-Indigenous Australians in the period 2011–12 to 2012–13). Rates were highest in the NT (2.7 per 1,000) and lowest in NSW (0.2 per 1,000). Between 2007–08 and 2009–10 rates of hospitalisation for Indigenous Australians were highest in the 10–14 year age group whereas for other Australians rates increased with age and were highest in the 65 years and over group. Indigenous Australians hospitalised for ARF/RHD were less likely than other Australians to have had at least one heart valve procedure performed (28% compared with 49%) (AIHW 2013g).
Rates of ARF and RHD among Indigenous Australians are among the highest in the world and large inequalities exist between Indigenous and other Australians (AIHW 2013g). Interventions that focus on improving housing, socio-economic circumstances and health care will be important for preventing and managing these conditions. Improved access to appropriate treatment for pharyngitis/tonsillitis is likely to reduce the rate of ARF. While it has been suggested that GAS skin infections may be a risk factor for ARF, particularly in Australia, there is currently insufficient evidence to justify recommending skin health programmes exclusively for the prevention of ARF. More research is needed on the association between GAS skin infections and ARF (RHDAustralia 2012). There is considerable scope for the secondary prevention of ARF/RHD through the implementation of disease registers and control programmes, education of patients and their families, treatment with penicillin prophylaxis, and regular clinical review and access to specialists and hospital care. The Better Cardiac Care for Aboriginal and Torres Strait Islander People project is an initiative of the Australian Health Ministers' Advisory Council and is currently being led by NSW Health. One of the priority areas identified for this work includes strengthening the diagnosis, notification and follow-up of RHD. The Essential Service Standards for Equitable National Cardiovascular Care for Aboriginal and Torres Strait Islander people (ESSENCE) project developed 'essential service standards', defining elements of care and service delivery that should be accessible to all people with, or at risk of CVD, regardless of their location, ethnicity, economic circumstances or gender. The standards articulate what elements of care are necessary to reduce disparity in access and outcomes for five critical cardiovascular conditions, including RHD. ESSENCE II follows the completion of ESSENCE I in 2012 and is developing and piloting a primary health cardiovascular care resource kit (due for completion April 2015) and a set of key performance indicators. RHD registers are a central element of secondary disease prevention programmes to prevent recurrence of ARF and reduce the occurrence or severity of RHD. Control programmes improve case detection, and are the most effective way of improving compliance to treatment regimes and supporting clinical follow-up of people with RHD. The Australian Government is currently providing funding for register and control programmes in the NT, WA, Qld and SA, and a National Coordination Unit, RHDAustralia. Under the Rheumatic Fever Strategy (RFS) funding is provided to help improve the detection and diagnosis of ARF and RHD, and improve access to the antibiotic injections that prevent repeated attacks of ARF. The RFS provides funding of $11.6 million over four years (2012–13 to 2015–16) for state- based register and control programmes, and $2.6 million over three years (2012–13 to 2014–15) for the National Coordination Unit (NCU). The NCU supports the state-based programmes to operate in accordance with best practice clinical guidelines, develops national education, training and self-management resources, and is developing a performance monitoring system to improve the collection of data and reporting on incidence and prevalence.
Figure 1.06-1 shows the incidence of rheumatic heart disease among Aboriginal and Torres Strait Islander Australians between 2006 and 2013. Between 2006 and 2013 there was a 41% decline in new registrations of RHD among Indigenous Australians in the NT.
Source: AIHW analysis of Northern Territory Rheumatic Heart Disease Program Register
Figure 1.06-2 shows hospitalisations with a principal diagnosis of acute rheumatic fever or rheumatic heart disease, by age and Indigenous status, between 2007–08 and 2009–10. Between 2007–08 and 2009–10 rates of hospitalisation for Indigenous Australians were highest in the 10–14 year age group whereas for non-Indigenous rates increased with age and were highest in the 65 years and over group.
Source: National Hospital Morbidity Database (AIHW 2013g)