Māori are significantly more likely to die within 30 days of surgery than non-Māori, a disparity a surgeon has described as damning.
A new study, published today in the New Zealand Medical Journal, found that no matter the type of surgery, a significant disparity existed.
The study, led by Otago University's Jason Gurney (Ngāpuhi, Ngāti Hine), looked at the 3.9 million surgical procedures carried out in New Zealand between 2005 and 2017.
Looking at instances where someone died within 30 days of an operation, Dr Gurney said they found one common observation: "No matter where we look, Māori are more likely to die within 30 days of a surgical procedure."
That observation remained when they looked at 90-day results. There were some exceptions where the disparity was small, but they were in small fields like neurosurgery.
But across the board, for every 100 acute operations the 30-day mortality ratio for Māori was 1.1, compared to 0.7 for European. That meant Māori were 14 percent more likely to die within 30 days, the study said.
For elective or waiting list procedures, the ratio was 0.2 for Māori and 0.1 for European. That meant Māori were 35 percent more likely to die within 30 days of a procedure.
While post-operation deaths are rare, Dr Gurney said the numbers revealed a distressing disparity.
"They sound like small numbers, but when you're looking at millions of procedures it adds up to a lot of deaths, it also adds up to preventable deaths," Dr Gurney said.
"If there was equality between Māori and Europeans, fewer Māori would die - that's the bottom line."
Dr Gurney said there were many possible contributing factors, but even with several variables accounted for, like higher rates of Māori with underlying health issues, the imbalance remained.
"The stark disparities that we show in our paper are controlled for comorbidities. Even in the presence of comorbidity, even if you take that out of the equation, Māori are still much more likely to die within that post-operative period," he said.
"So it can also point us toward maybe other things to focus our attention on."
Dr Gurney said there were multiple causes that amounted to problems that were deeply systemic.
Māori had higher rates of underlying health issues, but also poorer access to primary health care. Research also shows that often, Māori receive a different standard of post-operative care, Dr Gurney said, and Māori were also more likely to have surgery in smaller, limited-capacity, hospitals.
He said it all pointed to a need for wholesale change to how things are done.
Auckland surgeon Jonathan Koea (Te Ātiawa, Ngāti Mutunga), who is also a member of the Royal Australasian College of Surgeons' Māori Advisory Group, said a disparity has always been assumed, but its extent was not fully known.
He said the numbers released today are "damning".
"You know it's an uncomfortable read that Māori are twice as likely to die after amputations as non-Māori, one third more likely to die after bowel resections, about 25 percent more likely to die after cardiac surgery," he said of the research.
"Those are not small figures of a few percentage points, those are quite big proportional increases."
Professor Koea, who was one of more than a dozen people to contribute to the study, said a multitude of reasons have added up to a single fact: The health system is not fair, nor is it delivering for Māori.
There are few Māori surgeons, he said, and the health system often had little understanding of Māori needs.
"You know I'm a surgeon, I'm as responsible for this as anybody else. And you have to acknowledge that hospitals everywhere are filled with very talented, highly committed individuals who truly do their best for everybody," Koea said.
"I hope that individual health providers will read it and take that on board. But I think acknowledging that the outcomes for all New Zealanders are not the same, that's a very important point to get to," he said.