Ingrid Stacey

Star Scientist - Ingrid Stacey

WA researcher Ingrid Stacey is looking to better understand how rheumatic heart disease affects First Nations people

6 December 2023

Despite being virtually eliminated in the general Australian population in recent decades, rheumatic heart disease (RHD) continues to disproportionately impact Aboriginal and Torres Strait Islander people. Young Aboriginal and Torres Strait Islander people with RHD are dying at rates that are a staggering 18 times higher than the non-Indigenous Australian population.

Cardiovascular epidemiologist and PhD student Ingrid Stacey is working with Dr Lee Nedkoff and the team at the Institute’s research hub in Western Australia to gather data on RHD rates and outcomes across Australia. This data plays a crucial role in advocacy and decision-making to help reduce the burden of this chronic, yet preventable, disease.

What does a cardiovascular epidemiologist do?

We measure the burden and patterns of cardiovascular disease in the population, including what might be contributing to increases or decreases in disease rates.

Ingrid Stacey and Dr Lee Nedkoff working in the laboratory

My expertise is in linked data, which involves gathering multiple data sources, including doctor’s records, hospital admissions and death records, and putting them together to understand what’s happening to individual people over time. We use this information to answer important research questions.

What research are you currently working on?

I'm looking at the outcomes of RHD and acute rheumatic fever (ARF) in young people. These are acquired diseases caused by infection with Strep A bacterium that usually causes a sore throat or a skin infection in childhood. When these infections are not treated promptly, a person's own immune system can potentially attack the heart valve tissues, causing serious consequences.

Unfortunately, First Nations Australians have some of the world's highest rates of ARF and RHD.

What impact does RHD have on the body?

It starts with ARF, which is an acute feverish episode that causes painful and tender joints, among other symptoms. The peak onset of ARF is between the ages of five and 14 years old.

ARF generally resolves within weeks or months, but once a person has had ARF they might develop antibodies that can attack and damage their heart valves. This long-term condition of damaged heart valves is called RHD. RHD increases the risk of severe complications like infective endocarditis, atrial fibrillation, heart failure, stroke, complicated pregnancies and even death.

Those people who have had ARF or RHD need to start monthly injections with penicillin to prevent the disease from worsening. These injections are painful and inconvenient. People who develop severe RHD might need a heart valve repair or replacement and will possibly take anticoagulant drugs for the rest of their life.

For under 35-year-olds with RHD, one in five with mild or moderate disease will progress to atrial fibrillation, heart failure, stroke, endocarditis, or death within eight years.

Why are Aboriginal and Torres Strait Islander people at higher risk for ARF and RHD?

Colonisation caused enormous disruption to the communities and culture of Aboriginal and Torres Strait Islander people, resulting in the ongoing socioeconomic differences we are all aware of today. This includes experiencing higher rates of poverty and unemployment, leading to inadequate hygiene and housing infrastructure which creates environments that cause the Strep A infections driving ARF and RHD to thrive.

If people who have had ARF don't have good access to healthcare, don't feel welcome at their local healthcare provider, or don’t see someone with an awareness of ARF and RHD, they’re less likely to be checked out and therefore less likely to have the infections treated.

RHD is 100% preventable – but only if the environmental health factors causing ARF and RHD are improved, and infections are treated promptly. It's easy to think that the answer is simple then, however Australia has a history of misguided attempts to 'fix things'. The best solutions will emerge when we listen to the voices and needs of individual First Nations communities, and bring together the wisdom of communities with what medical science has to offer.

What is the focus of your RHD research?

I’m working in Dr Nedkoff’s team in the Cardiology Population Health Laboratory. The research project I’m involved in is called the End RHD in Australia Study of Epidemiology (ERASE) and it’s led by my PhD supervisor and Theme Lead for Aboriginal Cardiovascular studies, A/Prof Judith Katzenellenbogen.

Ingrid Stacey and Dr Nedkoff walking down a hallway

ERASE was the first study that measured the rates of ARF and RHD across multiple Australian jurisdictions. My PhD uses the ERASE data to investigate the health outcomes for young people with RHD, including how they use the public health system. I have also looked at whether RHD Control Programs, which record everyone who has been notified as diagnosed with ARF and/or RHD, are working - and the answer is yes, but earlier interventions are needed. My first study measured health outcomes in young people who have mild or moderate illness and found that they're still progressing to severe outcomes quite quickly, despite being in a country with seemingly good healthcare.

I recently published a mortality analysis, which fortunately found that RHD death rates had approximately halved since they were last measured. But interestingly, among people with RHD who died only 15% of deaths had RHD as the underlying cause – people also died from other chronic illnesses including diabetes, respiratory disease, and cancer. So RHD is interacting with other diseases to cause premature death.

As a side study, we looked at how well we are capturing RHD deaths, and unfortunately, there seems to be a fair bit of missing data, especially for Aboriginal and Torres Strait Islander people. Unless people can be counted, we can't really tell the story that needs to be told.

You mentioned that RHD rates in Australia have been decreasing. Can you tell us more about that?

We looked at RHD deaths between 2010 and 2017 and found that mortality had decreased in the younger age group of 25- to 44-year-old Aboriginal and Torres Strait Islander people. In this group, RHD-underlying mortality has halved from 7.55 deaths per 100,000 person-years (for 1997-2005) to 2.63 deaths per 100,000 person-years (for 2010-2017), which is good news.

Despite the decrease, these young First Nations people are still dying from RHD at 18 times higher rates than other Australians. So whilst there has been progress, there is still substantial room for improvement.

What do you think has contributed to declining rates of RHD?

There is strong leadership among Aboriginal and Torres Strait Islander people. The National Aboriginal Community Controlled Health Organisation (NACCHO) has been leading the way with a newly established unit dedicated to RHD prevention, advocacy, and awareness.

There are also communities that have designed successful health promotion and prevention programs that tackle the issues in a way that's appropriate for their communities - a great example of this is "On Track Watch".

The Register Control Programs also play their part - they identify people with ARF and RHD and follow them up over time. They send reminders for ongoing health care and for regular penicillin injections, which prevent ARF recurrence and reduce the risk of developing RHD.

What prompted your career change and returning to study to complete a PhD?

I was working as a cell biologist and I found myself in the lab thinking ‘why are we sending all the results to a statistician?’ - I really wanted to analyse the data myself! So I enrolled in a Masters of Biostatistics.

From there the decision to do a PhD was the fortunate combination of a few things at the right time – a great project arose, my supervisor and mentor A/Prof Katzenellenbogen was willing to take me under her wing, and my children had started full-time schooling. So far the PhD experience feels similar to full-time employment, but I’m sure that feeling will change as the submission date gets closer. [laughs]

What are your interests and passions outside of the lab?

I've forgotten because I have two young children – so I'm basically a domestic servant when I'm not working [laughs]. I do my research while they're at school, and then when they're home, we're just doing the usual parenting things.

Ingrid with her family with a quokka

When we go out together as a family we enjoy going to the beach and spending time outdoors. I also try and fit in the gym and some dance classes where I can.

That’s great that you can work research around parenting responsibilities.

I’ve found my work to be incredibly flexible, with the post-COVID work-from-home arrangements being quite critical to this. The school my kids go to is close to home, so once they're at school I can get to work about 5 minutes later. Then in the evening I’ll do some more work while they're out at sporting activities or doing homework.

I am fortunate to have fantastic female supervisors and mentors who completely understand this stage of life and have guided me through managing a PhD with children.

Acknowledgement of Country

The Victor Chang Cardiac Research Institute acknowledges Traditional Owners of Country throughout Australia and recognises the continuing connection to lands, waters and communities. We pay our respect to Aboriginal and Torres Strait Islander cultures; and to Elders past and present.

Victor Chang Cardiac Research Institute - The Home of Heart Research for 30 Years