Fewer Pacific And Māori Babies Survive with Heart Condition
New research shows the survival rates of babies with a rare but potentially fatal heart defect is lower for Pacific and
Māori compared to European babies.
Researchers say it is another example of inequity in health outcomes that raises the question of whether methods of
healthcare provision contribute to these different outcomes.
The study also showed that babies of European ethnicity were more likely than other ethnicities to have the condition,
called congenital critical left heart obstruction (LHO), in which the left side of babies’ hearts does not form
Liggins Institute researcher, neonatologist and PhD student Dr Elza Cloete will present the new findings on Tuesday at a
major gathering of international mother and baby researchers and health professionals in Auckland, the Perinatal Society
of Australia and New Zealand (PSANZ) Annual Scientific Congress 2018.
Dr Cloete analysed New Zealand health statistics on the condition over a nine-year period as part of her PhD, working
with her supervisors Professor Frank Bloomfield, Liggins Institute Director and neonatologist at Starship Hospital, and
Dr Tom Gentles, Director of the national paediatric cardiac service at Starship Hospital. They found that:
• The incidence of LHO was highest in European fetuses and babies (0.59 per 1,000), followed by Māori (0.31 per
1,000) and then Pacific (0.27 per 1,000). Across all ethnicities, it was 0.43 per 1,000.
• Management options taken during pregnancy and shortly after birth varied among ethnic groups. Higher pregnancy
termination rates were found in Europeans, but more stillbirths and higher palliative care rates were recorded for Māori
• Survival to one year was highest in European babies at 58 percent, compared to 44 percent for Māori and 41
percent for Pacific.
Says Dr Cloete, “Ministry of Health figures clearly show that Māori and Pacific families experience inequities across
maternal health and access to care – true across the broader health care sector. Despite that, I don’t think we were
anticipating these results. The differences in perinatal outcomes in particular is quite striking.”
Dr Cloete says there is probably a combination of reasons for these differences.
“We know that Pacific families seek out antenatal care later in pregnancy compared to other ethnic groups. In addition,
how a particular mother and baby are cared for at each step will be influenced by the cultural and religious beliefs of
the family, as well as by their health literacy,” she says.
Where families live and their ability to travel to the country’s paediatric cardiac intervention centre at Starship
Hospital could also influence outcomes, as could differences in socioeconomic status, health literacy and disease
“We also have to consider the possibility of healthcare provider bias,” says Dr Cloete. “Much has been written about
unconscious bias in medicine. When health professional counsel families, we may guide them towards the decision that we
think is appropriate for them based on our own bias, rather than present them with all the options that will allow them
to make the best decision for their family. Those biases may be shaped by our own religious beliefs, cultural awareness,
and societal influences – how ethnic groups are portrayed – or perhaps previous experiences.”
On the other hand, differences in the incidence of these heart defects suggests a genetic component, she says. “We know
that the risk of LHO is higher among close relatives of an affected person.”
Dr Gentles says although the condition is rare, it affects families profoundly.
“These types of conditions are very difficult for families to cope with and adjust to. Making a diagnosis during
pregnancy places a great deal of stress on mothers and families, but it does mean that families are aware of treatment
options at an early stage,” he says.
“If a diagnosis is not made before birth babies become very sick. They may die before they can be treated, their
recovery may be much more complicated and prolonged, and of course their family will be in shock given the unexpected
In the past year, Starship has introduced a dedicated team that works closely with healthcare services around New
Zealand to monitor and support caregivers of babies with LHO. Early results suggest that this initiative has improved
survival in these fragile infants.
Dr Cloete says further research is needed to understand the disparities – not only in cardiac defects but other
congenital conditions or syndromes diagnosed during pregnancy.
“Families should be supported to make the decision that they believe is best for their child. As healthcare
professionals, we have an obligation to present the information to them in an unbiased way,” she says.
The study is part of a larger body of work the team is doing towards establishing a nationwide pulse oximetry screening
programme for the detection of critical heart defects in newborns.