Prediabetes label unhelpful, experts argue

“Pre-diabetes label ‘worthless’, researchers claim,” reports the BBC.

The headline is based on an opinion piece published in the British Medical Journal (BMJ) by John Yudkin and Victor Montori, both of whom are professors of medicine.

They argue that diagnosing people with “prediabetes” puts people at risk of unnecessary medicalisation and creates an unsustainable burden on healthcare systems.

The piece is part of an ongoing BMJ series called “Too much medicine”, which is examining what is known as over-medicalising – treating “problems” that don’t actually require treatment.

They argue that money would be better spent changing food, education, health and economic policies.

This is an opinion piece. Although the authors support their opinions with studies, other evidence available could contradict their views.

What is meant by ‘prediabetes’?

Prediabetes is used to describe people at risk of diabetes because they have impaired glucose metabolism, but who do not meet the criteria for diabetes and often have no noticeable symptoms.

It is a term that was introduced by the American Diabetes Association (ADA), but has not been accepted by other health organisations, such as the World Health Organization (WHO).

It may be defined as:

• impaired glucose tolerance
• above normal glucose blood concentration after fasting
• above normal glycated haemoglobin (a marker of average blood glucose concentration)

Supporters of the term’s usage argue that it allows doctors to identify high-risk patients, so they can be treated in order to prevent diabetes from occurring.

What objections do the authors have about the use of the term?

The authors point out that there has been little support for the ADA’s prediabetes label from other expert groups, including WHO, the International Diabetes Federation and the UK’s National Institute for Health and Care Excellence (NICE).

The authors say this is because the ADA has lowered the thresholds for impaired fasting glucose and glycated haemoglobin. Because it encompasses all three aspects of impaired glucose metabolism (impaired glucose tolerance, above normal fasting blood glucose, above normal glycated haemoglobin), the lowered thresholds have created a large, poorly characterised and heterogeneous (mixed) category of glucose intolerance.

In other words, the diagnostic criteria are now so broad (in the opinion of the authors) that it is, essentially, useless.

The authors say that using the ADA’s definition of prediabetes would result in two to three times as many people being diagnosed with impaired glucose metabolism. This would lead to 50% of Chinese adults being diagnosed with prediabetes – over half a billion people.

The authors also question the value of diagnosing people with prediabetes.

They point out that the drugs used to treat people with prediabetes in order to stop them developing diabetes are often the same as the drugs they would take if they actually developed diabetes.

The side effects of these drugs must be measured against the fact that many people with prediabetes, who remain untreated, will not go on to develop the condition.

They also discuss the merits of lifestyle interventions, such as regular exercise and improved diet.

They point out that these types of interventions are of use for all adults, so they question the wisdom of only promoting these interventions to specific groups. A better use of campaigning would be to target all adults, they say.

What dangers or risks do they claim could occur by using the term?

The authors suggest that a label of prediabetes, while not causing any physical symptoms, could still cause:

• problems with self-image
• anxiety about future complications
• challenges with insurance and employment
• a need for medical care and treatment
• increased healthcare costs
• medication side effects, if prediabetes is treated with drugs

In their opinion, the diagnosis would cause more problems than it solves.

What do the researchers suggest instead?

The researchers say that the risk factors for developing a whole host of chronic diseases overlap, and that money would be better spent changing food, education, health and economic policies.

What should I do if I have been told I have prediabetes or that I am at high risk of developing diabetes?

If you have been told you have prediabetes, or that you have a high risk of developing diabetes, you can reduce your risk of developing the illness by:

• being physically active
• achieving or maintaining a healthy weight
• eating a balanced diet
• stop smoking if you are a smoker

Read more advice about lowering your diabetes risk.