Laboratory testing and bloodwork results are very helpful to make the diagnosis. We look for elevations of the blood sugar, elevations of the fasting insulin level and elevations of triglycerides.
Often we will find mild elevations of the liver function tests which indicates the deposition of fat in the liver which is another condition caused by insulin resistance.
The cholesterol or lipid panel may also show low HDL or “good” cholesterol. Very often low HDL and high triglycerides occur together.
Sometimes a patient will have many symptoms of insulin resistance but not very many abnormalities on lab work. The laboratory findings can be subtle initially, and may reveal high fasting triglycerides or high normal fasting triglycerides.
Usually, the lab value that becomes elevated next is the fasting insulin. Fasting insulin may be elevated for years before any hint of problem with the blood glucose is seen.
An evaluation of fasting insulin is not typically part of the lab work profile done in an annual physical, which is why many people may have insulin resistance and are surprised they have never heard about it before.
The physical exam I perform on every patient gives clues about their state of insulin resistance.
· The first is the abdominal deposition of fat. One of the criteria for Metabolic Syndrome (an advanced form of insulin resistance) is a waist circumference of greater than 35 inches for a woman and greater than 40 inches for a man.
· Elevated blood pressure in the range of 135/85 or higher without medication to lower it, is a diagnostic criterion for insulin resistance. Having high blood pressure which is treated well with medications also remains a diagnostic criterion for insulin resistance.
· Sometimes we will find a dark coloration of the skin around the neck which is called Acanthosis Nigricans. It may appear that the neck is dirty but this is not a condition of hygiene at all. It is a marker for insulin resistance. People may notice this darker colored skin in other areas as well such as where there are skin creases. Another skin sign of insulin resistance can be a lot of little skin tags around the neck and head area.
Elevations of the blood sugar above 100 is a later finding in insulin resistance. However, even if a patient has elevated insulin or even has diabetes, there is often a great deal that can be done to reverse and correct insulin resistance. Many patients of mine who entered my practice taking medication for diabetes including insulin injections have been able to reduce or even eliminate medications entirely.