A research study led by Immunology Registrar Dr Jacqui Gale has shown Māori and Pacific Peoples are screened for coeliac disease and lupus (two autoimmune diseases) at around 55 – 60 percent the rate of European individuals.
“The results are interesting. We suspected there would be a gap in testing rates when we started the project, and the data confirmed this,” says Jacqui.
Jacqui began her research in 2023, analysing laboratory data for antibody tests used in the investigation of coeliac disease and systemic lupus erythematosus (SLE). She looked at 52,000 anti-tissue transglutaminase (anti-tTG) screens, which are used to detect coeliac disease, and 25,000 antinuclear antibody (ANA) screens, commonly used in the assessment of lupus and related autoimmune conditions. The tests were performed between 2020 and 2023 and covered patients in Wellington, Hutt Valley, Wairarapa, and Taranaki.
“We looked at how screening rates and positivity varied by ethnicity and region. What we saw was consistent across all four areas. Europeans and other ethnic groups were screened more often than Māori and Pacific populations, for both conditions,” says Jacqui.
“Europeans were screened about 1.6 times more than Māori and 1.8 times more than Pacific Peoples for ANA. The pattern was similar for coeliac disease, with Europeans screened 1.6 times more than Māori and 2.5 times more than Pacific Peoples.”
Jacqui says she had expected to see higher ANA positivity rates for Māori and Pacific Peoples based on the known increased prevalence of lupus in these groups. There is limited data on coeliac disease prevalence by ethnicity in Aotearoa New Zealand.
“The similar ANA positivity rates across ethnic groups were unexpected, given the higher lupus burden in Māori and Pacific Peoples. This suggests lower screening rates are contributing to missed or delayed diagnoses. This can mean people present later, with more advanced or severe disease. It really underscores the need for more equitable testing strategies in New Zealand,” says Jacqui.
While the research has shown clear gaps in testing and a need to improve access for Māori and Pacific Peoples, the solution is not to increase testing across the board. Screening tests like ANA and tTG can produce false positives, particularly when used indiscriminately.
“This study is about raising awareness among referrers, rather than increasing unnecessary testing. It’s about helping people recognise the symptoms of lupus and coeliac disease, especially in Māori and Pacific patients, so that the right tests are requested when they’re needed,” says Jacqui.
“It is also about informing further work on greater community outreach to increase screening and more equitable health outcomes across the country. I’ve submitted my study to the Royal Australasian College of Physicians as part of my training, and I’m proud to have contributed to this space.”
Click here to view an earlier article on Jacqui’s research and the background to the study.