Obesity diagnosis recommendations reflect the complexity of the condition but risk unintended consequences – LCP
Health analytics
This week, the Lancet called for an overhaul of the current simple definition of obesity and proposed separating it into two distinct categories: pre-clinical and clinical obesity.
The new two-tier definition of obesity moves away from simple body mass index (BMI), which classifies individuals as obese based solely on a BMI over 30. Instead, it distinguishes ‘clinical obesity,’ where an individual has a BMI over 30 and a larger waist circumference alongside clinical complications and/or impacts on daily living. This is compared to ‘pre-clinical obesity,’ whereby an individual has a BMI over 30 and a raised waist circumference but no organ dysfunction or clinical complications.
Health experts at LCP see the Lancet Commission as an important contribution to the increasing public health and societal issue of obesity and agree that current diagnostic approaches and metrics, such as BMI, are imperfect. However, alongside diagnostic criteria for alternative metrics such as excessive body fat is not well established, there are three major areas of caution:
- BMI remains a relatively available and important measure for identifying population-level risk within populations. Public health measures that shape the environment to make the healthy choice the easy choice is likely to have the most effective and equitable impact on preventing obesity across nations; BMI is important to guide this.
- The proposed pre-clinical obesity group risks inequalities between people living with ‘controlled’ obesity and those living with controlled other long-term conditions such as high blood pressure or diabetes.
- The proposed criteria suggest that treatment and control efforts would be delayed until an individual has obesity complications. This is at odds with the UK Government’s aim to ‘shift to prevention’ and we know that earlier intervention and secondary prevention of chronic conditions are highly effective for individuals and lead to wider economic outcomes in turn.
Obesity is a major public health issue globally with implications far beyond the healthcare system. Our recent analysis estimates that the total annual welfare savings to the UK Treasury if everyone with obesity was effectively managed and able to be economically active could be over £10bn per year. We need three complementary preventive efforts to obesity: preventing the onset of obesity, preventing the progression of obesity to higher BMIs and preventing the onset and impact of obesity clinical complications. This requires both public health and medical interventions and an ability to identify and preventively manage people with obesity who have not yet developed clinical complications.
Dr Jonathan Pearson-Stuttard Partner and Head of Health Analytics at LCP
