Having normal blood sugar levels is no guarantee against developing type 2 diabetes down the road, according to researchers. What should we do with a person with a fasting blood sugar on the higher end of normal between 91-99 mg/dL who has a two-fold difference in risk of developing diabetes…
The diagnosis of diabetes started with a fasting blood sugar of 180mg/dL, then was changed to 140mg/dL, then eventually was dropped to 126mg/dL. Now we are adding a new disease called prediabetes, diagnosed with a blood sugar of 100-126mg/dL. This study now says we should look at lowering the number even more. Maybe we should just tell patients that anything above normal can be dangerous over time.
In fact, they report in the journal Diabetes Care, people at the high end of what’s considered the normal blood sugar range are twice as likely to get the disease as are those in the low end.
But does that mean doctors should treat these people any different, as the researchers suggest? Not at all, said one expert who wasn’t involved in the new work.
Dr. Michael LeFevre, a family physician at the University of Missouri in Columbia, stated that, "The concern here is that people get started on medications at a level below the conventional threshold for diabetes."
"My personal recommendation is that people should strive to manage their weight and be physically active irrespective of what their blood (sugar) level is," he added. Type 2 diabetes is a lifestyle disease in which the body no longer responds appropriately to the hormone insulin, which helps ferry sugar from the blood into our cells after a meal.
When fasting blood sugar levels reach 126 milligrams or more per deciliter, doctors will diagnose diabetes, because too much sugar in the blood will cause severe damage to the heart, kidneys and other organs over time.
Traditionally, blood sugar levels below 100 milligrams per deciliter have been considered safe, whereas levels between 100 and 126 signal a higher risk of diabetes — termed prediabetes.
But according to the new study, by Dr. Paolo Brambilla and colleagues at the University Milano Bicocca in Italy, the currently accepted "normal" blood sugar range might be too wide.
The researchers looked at data for nearly 14,000 men and women who’d had blood drawn several times at their clinic. The patients were between 40 and 69 years old and all of them had normal blood sugar levels at first. Over the next seven to eight years, on average, about two percent of the women and nearly three percent of the men developed diabetes.
Less than one percent of those who started out with fasting blood sugar levels between 51 and 82 milligrams per deciliter wound up with the disease, while more than three percent did so if they had values between 91 and 99.
After controlling for other factors that might influence the likelihood of getting diabetes, the higher values corresponded to a two-fold difference in risk of developing the disease.
The findings are in line with an earlier study from Oregon, and the Italian researchers say they can help identify the people who need extra medical attention. According to the American Diabetes Association, more than 79 million have prediabetes.
But LeFevre, who’s a member of the U.S. Preventive Services Task Force, a federally supported expert panel, said he was concerned about the label "prediabetes," let alone expanding the range downward into lower blood sugar ranges.
"We don’t know that there is a magic threshold" for blood sugar, he said. "As the blood sugar goes up, the risk of complications increases."
Diabetes Care, online April 15, 2011