Does Prediabetes Matter?
At the EASD 2021 conference, leading healthcare professionals discussed the importance of prediabetes, what the science says about its complications, and how we should approach treatment.
Before type 2 diabetes develops, people often have a condition called prediabetes. Prediabetes occurs when a person's A1C is higher than what’s considered the normal range (less than 5.7%), but not high enough to be diagnosed with diabetes (6.5% or greater). People with prediabetes have insulin resistance, which occurs when the body’s cells do not respond normally to insulin and as a result, glucose levels begin to increase in the blood. If no actions are taken to reduce a person’s glucose levels, prediabetes can progress to type 2 diabetes.
Prediabetes is also known or measured as either “impaired glucose tolerance” (IGT) or “impaired fasting glycemia” (IFG).
“With an increasing prevalence of diabetes worldwide, there is also an increase in prediabetes,” said Dr. Dan Ziegler of the German Diabetes Center in a symposium delivered at the EASD 2021 conference. And according to Dr. Coen Stehouwer of Maastricht University in the Netherlands, “Prediabetes prevalence is extremely high, about double the diabetes rate in society.”
Prediabetes affects about 88 million adults in the US, and an estimated 84% of people with prediabetes don’t know they have it. According to the CDC, 15-30% of these individuals will go on to develop type 2 diabetes within five years. In other words, more than 26 million people who currently live with prediabetes could develop type 2 diabetes by 2026.
This condition is also a major problem globally. According to the International Diabetes Federation, the global prevalence of prediabetes in 2017 was around 7.3% or over 352 million people. Estimates show that those numbers will increase by 2045 to 8.3% or over 587 million people worldwide.
Association with complications
“In terms of its consequences, prediabetes is, simply, early diabetes,” said Stehouwer.
That is because prediabetes may increase the likelihood of multiple different microvascular and macrovascular complications such as retinopathy, cognitive dysfunction, hyperglycemia, neuropathy, and cardiovascular disease similar to diabetes.
Dr. Kristine Faerch of the Steno Diabetes Center in Copenhagen highlighted the strong connection between prediabetes and cardiovascular disease, even when considering factors like age, sex, smoking, and socioeconomic status.
“There is a 20% increased risk of cardiovascular disease in people with prediabetes,” compared to people with normal glucose levels, she said. Importantly, some of that risk is attributed to things outside of your glucose levels, like high blood pressure, cholesterol, and weight. Addressing all these factors together can help lower your risk for cardiovascular disease.
According to Zeigler, neuropathy has also increased in people with prediabetes, but people don’t often know that they have it. “The main problem is the unawareness of having neuropathy is extremely high – [this unawareness] is between 90-100% in people with prediabetes or newly detected diabetes,” he said.
Risk factors for neuropathy include age, height, obesity, postprandial glucose (glucose levels after a meal), and high levels of triglycerides in your blood. Studies also suggest that this complication is more common in women with prediabetes than in men with prediabetes.
“Screening for neuropathy should be considered in persons with prediabetes,” Ziegler said. “Long-term lifestyle intervention may improve nerve function in those with prediabetes.”
The connection between prediabetes and type 2 diabetes, along with their associated complications, underscore the importance of early treatment.
“Diabetes is a progressive, macrovascular, microvascular, and neuronal disorder that affects many organs,” said Stehouwer. “And all that starts with prediabetes.”
Fortunately, certain lifestyle interventions can delay or prevent the progression to diabetes, as the Diabetes Prevention Program Outcomes Study (DPPOS) showed. At the fifteen year mark of this follow up study, DPPOS showed that by focusing on diet and exercise, and by taking metformin (which is considered off-label for people with prediabetes), people can significantly reduce their risk for developing type 2 diabetes by up to 27%. The program has also proven to lower healthcare costs and reduce the risk of diabetes-related complications, including neuropathy, retinopathy, and cardiovascular disease.