Prevention our only viable option

They say prevention is better than a cure. It is also a lot cheaper than a cure.

 

A helpful new report on BMI and obesity seeks to clarify how we measure and define clinically relevant obesity, especially for treatment purposes.

 

But with New Zealand's health system under enormous pressure, we argue the best use of scarce resources is to target those at high risk of developing obesity, rather than just an "ambulance at the bottom of the cliff" approach.

 

The new report, published in The Lancet, raises issues that are critically important in the management of the global pandemic of obesity and highly relevant to  New Zealand, which has the third-highest rate of obesity in the world.  

 

New Zealand media coverage of the report has mostly centred on one of its messages: when considering the clinical relevance of an individual's high body mass index (BMI) it is necessary to also take into account the amount and distribution of body fat and whether there is already evidence that excess fat has adversely influenced body function.  

 

Most clinicians now accept that multiple health measures are needed to diagnose obesity.

 

BMI is an affordable and useful tool for determining health risk at a population level, but for individuals, additional measurements are needed to determine the health risks of excess weight, as outlined in The Lancet report, along with public health strategies to limit weight-based bias and stigma.

 

However, the focus on how BMI should be used may have overshadowed an equally, if not more important issue proposed in the new report, the suggestion that management of those with high BMIs should be under two categories: those with "pre-clinical obesity" and those with "clinical obesity", with particular emphasis placed on the needs of the latter. 

 

According to the report, clinical obesity should be diagnosed when there is evidence excess weight has adversely affected organs, tissues or body systems or limited day-to-day activities.

 

The condition is then actively treated, as are other chronic diseases.

 

The report acknowledges some people with pre-clinical obesity may require individualised treatments, but there is the assumption that such individuals will not need intensive medical management. 

 

While this approach may be appealing in that it identifies those who do or do not have a "disease", and is helpful in clinical practice, there are downsides. 

 

The risks associated with increasing levels of body fat and its consequences represent a continuum rather than a binary measure. This is also the case for other disease risk factors like increased blood pressure and smoking. 

 

Furthermore, disease risk factors typically act synergistically.

 

Given that many people with preclinical obesity have multiple disease risk factors, there will be a significant number at high risk of an adverse outcome. Some people with a condition called pre-diabetes could be in this situation.

 

Pre-diabetes can progress to type 2 diabetes, and is a common consequence of obesity.

 

With 228,000 New Zealanders currently living with type 2 diabetes, the costs to the health system of treating this disease are already high. 

 

An example of just one of the many complications of diabetes is kidney failure, with half of those receiving dialysis in New Zealand living with diabetes.

 

However, there is excellent evidence appropriate management of pre-diabetes can reduce the risk of progression to clinical diabetes and the inevitable health and financial consequences of this disease.

 

Overall, type 2 diabetes has been estimated to cost the New Zealand health system $2.1billion per year and this cost is projected to rise to $3.5b by 2040, according to the 2021 "Economic and Social Cost of Type 2 Diabetes" report.

 

Another issue with focusing resources primarily on treating clinical obesity is that proven treatments for obesity are expensive and not readily accessible in New Zealand.

 

With limited money for treatment, and costs projected to escalate as rates of obesity increase, prevention is our only viable option to deal with the obesity epidemic.

 

We need a focus on preventing obesity and type 2 diabetes, not waiting until clinical obesity and type 2 diabetes have developed with resulting adverse effects for individuals, whānau, productivity and health.

 

The government appeared to dismiss the Public Health Advisory Committee 2024 report which included many evidence-based prevention measures that would reduce levels of obesity and type 2 diabetes.

 

Other countries are implementing policies that help prevent obesity, with positive results.

 

Given that treatments for obesity are difficult and expensive to access, and the current financial constraints on New Zealand healthcare, we have little choice but to embrace prevention measures to prevent obesity and type 2 diabetes.

 

Our future health and health system depends on it. - Newsroom