Only a fraction of morbidly obese Australians who could potentially benefit from bariatric surgery will have any chance of accessing it, concludes a review that calls for an urgent rethink of obesity management.
Health economists from Victoria and Tasmania used a population model to estimate the likely numbers of people eligible for public bariatric surgery using the Australian New Zealand Metabolic and Obesity Surgery Society (ANZMOSS) framework published in 2020, yet to be formally adopted by the Australian health system.
They estimated that if a five-year program to treat all currently eligible patients was implemented, the maximum yearly demand was a projected 341,343 primary surgeries, more than eight times the existing capacity of the public and private sector combined.
A nine-fold increase was expected if both current and newly eligible patients were treated over the five-year time frame.
One particular challenge was that the ANZMOSS framework incorporated the Edmonton Obesity Scoring System (EOSS) as a key element of its recommendations on eligibility criteria, meaning more patients would be eligible for surgery compared to previous NHMRC guidance, the authors noted in their paper published in Obesity Surgery.
However, robust estimates of the prevalence and distribution of EOSS in the Australian population are not readily available.
“If EOSS scores are to be used to guide decision-making, there is an urgent need for rigorous local research to establish the true prevalence and distribution of EOSS scores by obesity class, and also to explore patient perceptions of their likelihood of taking up bariatric surgery were it available to them, to allow more accurate estimates of both eligibility and likely uptake,” they wrote.
The potential scale of the challenge highlighted by their results suggests the need for a deeper and wider debate on the aims, methods, and costs of all potential delivery models required to treat and manage obesity in Australia, not just bariatric surgery, they said.
“Any attempt to increase access to bariatric surgery in Australia requires significant additional resources to be allocated to the public hospital system in the first instance. As the number of people with obesity increases, clear eligibility criteria for bariatric surgery and the capacity to meet that demand remain unresolved issues in the Australian health system,” they wrote.
“National strategy on obesity in Australia has overwhelmingly focused on prevention. It is time for a major national review of all effective management and treatment options for the millions of Australians who are already affected by obesity,” they concluded.
The ANZMOSS framework differs from NHMRC recommendations on bariatric surgery eligibility. According to the NHMRC guideline for the Management of Overweight and Obesity in Primary Care, bariatric surgery might be considered for adults with BMI > 40 kg/m2, or adults with BMI > 35 kg/m2 and comorbidities that may improve with weight loss, taking into account the individual situation, or people with a BMI > 30 kg/m2 who have poorly controlled type 2 diabetes and are at increased cardiovascular risk.