What is “incident” Type 2 diabetes? The medical definition is the diagnosis and first intervention for the medical condition Type 2 diabetes mellitus. In clinical practice, “incident” diabetes is generally still defined as two successive office visits with fasting blood glucose (FBG) readings of ≥126mg/dl or a single A1c ≥6.5%.
The American Diabetes Association standard for diagnosing incipient Type 2 diabetes has changed over the years and continues to be controversial. In 1997, the FBG threshold was lowered from 140mg/dl to ≤126mg/dl. In 2009, the inexpensive A1c test, which measures the percent sugar on the surface of red blood cells (whose life is 2 to 3-months), became the new standard, and the A1c incident diagnosis criterion was lowered from 7.0% to 6.5%.
The A1C blood test is now the preferred method because it simulates the continuous level of glucose circulating in our blood, including the “excursions” (spikes) in postprandial blood sugar levels after eating meals and snacks. This “averaging” method is a more accurate measure of insulin resistance (IR) when “challenged” by a carbohydrate load. Insulin Resistance is the underlying mechanism responsible for high blood sugar (Type 2 diabetes).
Most clinicians still follow the guidance of the American Diabetes Association and strive, initially thru “lifestyle intervention” and then pharmacotherapy, to maintain a patient’s A1C at ≤7.0mg/dl. That translates to an estimated Average Glucose (eAG) of 154mg/dl and assures that the disease, and the pharmacotherapy, will be progressive. That means, eventually, that complications and co-morbidities like cardiovascular disease, kidney disease, neuropathy and retinopathy, are inevitable. In clinical practice most practitioners are complicit in the sense that their hands are tied by “Guidelines.” I don’t mean self-interest, but the trail of breadcrumbs tells a cautionary tale.
Quest Diagnostics lab reports state the current A1C “reference intervals,” as published annually in Diabetes Care, the Journal of the American Diabetes Association, are a guide to the diagnosis of incident Type 2 diabetes. They are:
< 5.7% Decreased risk of diabetes
5.7-6.0% Increased risk of diabetes
6.1-6.4% Higher risk of diabetes
≥6.5% Consistent with diabetes
A plain speaking translation of this very lax ADA standard for “incident Type 2 diabetes” is : ≥6.5% = You’ve got Type 2 Diabetes, period; 6.1-6.4% = You’re Pre-Diabetic; 5.7-6.0% = You’ve got “impaired glucose tolerance” (IGT); and <5.7% but rising = you’ve got “impaired fasting glucose” (IFG). In each case, it is telling you that you are Insulin Resistant (Carbohydrate Intolerant), and you’ve lost beta cell function, i.e., your ability to make your own insulin.
These stages are the “Natural History of Type 2 Diabetes.” They are described more fully in Retrospective #99, which is based on Dr. Ralph A. DeFronzo’s Banting Award Lecture at the ADA’s 2008 convention.
In the full paper published in the ADA Journal, Diabetes, Dr. DeFronzo says, “In summary, our findings demonstrate that, at the stage of IGT, individuals have lost over 80% of their β-cell function…” In the next section, “Pre-Diabetes,” he adds, “The clinical implications of these findings…are that the physician must intervene early, at the stage of IGT or IFG, with interventions that target pathogenic mechanisms known to promote β-cell failure.”
As a physician/researcher, Dr. DeFronzo cannot be faulted for advocating that “the physician must intervene early.” But how about the patient? The intervention that best targets the mechanism that kills beta cells is dietary. Eating carbs forces the pancreas to work. As you reduce carbohydrates, you spare your pancreas. It’s that simple, folks.“Lifestyle interventions” can work, but not if the dietary message is wrong. Dietary changes, if initiated and continued by the patient, if the changes are the right ones, will work. If you eat right, in a way that spares your pancreas, it will allow you to burn body fat for energy and maintain stable blood sugars. That “right” Way of Eating is Very Low Carb. Reading this blog, for your amusement/edification, is a far better “lifestyle intervention,” IMHO.