A ‘postcode lottery’ is denying people with obesity access to weight loss surgery through the public health system in
some parts of Aotearoa New Zealand, researchers say.
Across different DHB regions, public funding and rates of bariatric surgeries relative to local morbid obesity
prevalence vary by over 16-fold, a University of Auckland-led study has revealed.
The study, published in Internal Medical Journal, has for the first time calculated the number of surgeries relative to the number of people with very high BMI living in
each region.
Bariatric surgery, which includes stomach stapling and gastric bypass, is performed on the stomach and/or intestines to
help a person with serious obesity lose weight. It is the most effective treatment for this condition, leading to lasting weight loss, improved quality of
life, remission of type 2 diabetes and reduced heart disease and cancer risk.
The researchers collected surgery data over two years, from July 2013 to June 2015, and worked out regional totals per
1000 people with a BMI of 40 or greater. They found that of approximately 400 bariatric surgeries being performed in the
public health system each year, the rates varied widely, from 8.8 surgeries per 1000 people living with serious obesity
in the Counties Manukau DHB region and 4.9 per 1000 in Waitemata, to lower than 0.5 surgeries per 1000 in MidCentral and
Taranaki - both regions with more than 5000 people affected by obesity.
Another stark contrast was between Canterbury DHB and Waitemata DHB (north and west Auckland). Despite the two regions
having similar total population and prevalence of very high BMI (411,700 and 2.9 percent in Canterbury, 439,850 and 2.7
percent in Waitemata), the surgery rates were 1.1 percent and 8.8 percent (13 and 104 surgeries) respectively.
Associate Professor Rinki Murphy, in the University’s School of Medicine and endocrinologist at both Auckland and
Counties DHBs, led the study with DHB public health and surgical colleagues.
“At the moment, your chances of getting bariatric surgery are influenced by where you live,” she says. “Our findings
indicate that New Zealand’s public funding allocation for bariatric surgery needs to take into account local prevalence
of morbid obesity.
“While most DHBs delivered a higher number of bariatric surgery procedures than the Ministry of Health funded targets,
overall New Zealand’s national rates of public-funded bariatric procedures at 2.7 per 1000 morbidly obese patients is
less than half the rate in the UK and Australia.”
Dr Murphy says the health system needs to urgently respond to the rising numbers of people affected by obesity.
“We need to work harder to eliminate inequities by geographic region, and to provide better and more transparent
approaches to prioritising patient selection for this limited resource, along with more research to understand how to
best serve our populations.”