Prediabetes: A lesson in PR
What is Prediabetes?
Prediabetes is no doubt a term that we are all familiar with. But what does it mean for our health and should we be worried about it? Before we start, let’s look at the definition
According to Diabetes UK, “Prediabetes means that your blood sugars are higher than usual, but not high enough for you to be diagnosed with type 2 diabetes. It also means that you are at high risk of developing type 2 diabetes. You are unlikely to be experiencing any symptoms with prediabetes.
Prediabetes is also sometimes called borderline diabetes. Higher than normal blood sugars can be detected via blood tests. The medical terms for higher-than-normal
blood sugars are:
- Impaired Fasting Glucose (IFG)
- Impaired Glucose Tolerance (IGT)
- Impaired Glucose Regulation (IGR)
- Non-diabetic hyperglycaemia”
Impaired Fasting Glucose (IFG) is a glucose levels of 100 to 125 mg per dL (5.6 to 6.9 mmol per L) in patients who have fasted for 12h.
Impaired Glucose Tolerance (IGT) is a glucose levels of 140 to 199 mg per dL (7.8 to 11.0 mmol) two-hour after a 75-g oral glucose load (i.e. a glucose tolerance test).
The history of prediabetes
In 1997, the American Diabetes Association (ADA) introduced the term fasting glucose (IFG) as a fasting plasma glucose of 110–125 mg/dL (6.1–6.9 mmol/L), and this was soon adopted by the World Health Organization (WHO).
According to an article published in Science in 2019, pre-diabetes was “born as a public relations catchphrase. In 2001, the PR chief of the American Diabetes Association (ADA) approached Richard Kahn, then the group’s chief scientific and medical officer, for help with a vexing problem, Kahn recalls. ADA needed a pitch to persuade complacent doctors and the public to take seriously a slight elevation in blood glucose, which might signal a heightened risk of type 2 diabetes.”
Whilst the term pre-diabetes had been used prior to this, once the ADA removed the terms IFG and IGT from all their literature and replaced it with “pre-diabetes” it immediately took off.
In 2003, the ADA lowered the criterion for IFG to from 110 to 100 mg/dL (5.6–6.9 mmol/L) because they noticed that more people with IGT were going on to develop diabetes then those with a IFG. They decided that lowering the threshold of IFG was the best way to redress the balance. Interestingly, the WHO did not adopt this change because of the lack of evidence.
That didn’t stop the ADA and Centers for Disease Control and Prevention (CDC) declaring a “war on pre-diabetes” in the early 2000s. This was primarily led by the CDC diabetes prevention chief Ann Albright, who became an ADA board member from 2005 to 2009. The ADA claimed that impaired glucose tolerance significantly increased a person’s risk of developing diabetes and treating it early would reduce the number of people who went on to develop diabetes, and in doing so reduce the risk of cardiovascular complications.
The World Health Organization have always rejected prediabetes as a diagnostic category because they do not believe that there is any good evidence that IFG/IGT routinely leads to diabetes. There is also little evidence that existing treatments are effective.
According to the aforementioned article in Science, “John Yudkin, a diabetes researcher and emeritus professor of medicine at University College London, describes the ominous warnings about prediabetes from ADA and CDC as “scaremongering.”” And Dr Khan is quoted as saying “Nobody really thought at the time, how ‘pre’ is prediabetes for all these people?”.
In 2009, the ADA, European Association for the Study of Diabetes (EASD) and the International Diabetes Federation (IDF), convened an expert committee to review research on a diagnostic blood sugar test, HbA1c. This had previously been used to monitor glycaemic control in Type 2 diabetics, but the committee agreed that it was reasonable to use the test as a diagnostic criteria for diabetes going forward. However, the IDF and EASD also rejected the term pre-diabetes in its entirety.
In spite of this, the ADA decided to against the committee and changed its definition of pre-diabetes to include an HbA1c level, which it further reduced from 6.0% to 5.7%. The CDC went along with this because the ADA essentially sets the standards and guidelines for diabetes care in the USA. They both claimed that 15% to 30% of untreated prediabetes patients progress to diabetes within 5 years.
In reality that number is as low as 2% per year and less than 10% over 5 years. Quite a significant difference.
In 2018, a Cochrane Review was commissioned with the following purpose:
“We wanted to find out whether raised blood sugar (‘prediabetes’) increases the risk of developing type 2 diabetes and how many of these people return to having normal blood sugar levels (normoglycaemia). We also investigated the difference in type 2 diabetes development in people with prediabetes compared to people with normoglycaemia.”
They found that most people who qualify as prediabetic under the ADA’s criteria never actually progress to diabetes over any period that has been studied. In fact, up to 59% of prediabetes patients returned to normal values up to 11 years later without any treatment. They advised doctors to “be careful about treating prediabetes because we are not sure whether this will result in more benefit than harm, especially when done on a global scale.”
The review concluded:
“Taking into consideration the uncertainty of the available evidence, as well as the fluctuating stages of normoglycaemia, Intermittent Hyperglycaemia (pre-diabetes) and T2DM, which may transition from one stage to another in both directions even after years of follow-up, practitioners should be careful about the potential implications of any active intervention for people ‘diagnosed’ with Intermittent Hyperglycaemia.”
The Diabetes Prevention Program Outcomes Study which started in 2002 and is still going, took 3000 pre-diabetics and randomly assigned them to a lifestyle intervention, metformin or control group. 6 years later 5.3%, 6.4% and 7.8% of them respectively had gone on to develop diabetes. There is still no evidence as to whether these interventions altered cardiovascular outcomes.
Dr Khan, who is responsible for coining the term pre-diabetes is now quoted as saying that when it comes to those in the pre-diabetic category, “if you screen for diabetes every 3 to 5 years, you’re fine”.
Benefits and Costs
Consider the cost of this PR stunt. Not just the financial cost to healthcare systems, public health services and individuals alike, but the emotional and social cost. Consider the role that weight stigma played in the diagnosis and management of a condition that turned not to be a condition after all. Now ask yourself who stood to profit?
Who benefited the most from the billions of dollars that has been spent on pre-diabetes management over the year?
Now take a look at a list of the ADA’s corporate sponsors:
- Novo Nordisk
- Eli Lilly
[You’ll find similar sponsors for diabetes organisations across the world including Diabetes UK who have just as large a role to play in developing guidelines and funding research as the ADA does in the USA].
Finally, ask yourself who suffered the most from this PR campaign? Fat people. Black and other racialised people. People in the lowest castes* who generally have larger bodies, less money and are considered most expendable.
[*I used the term caste as described by Isabel Wikerson in Caste: The origins of our discontent.]