In general, prediabetes is not associated with any specific symptoms. However, there may be indicators of problems in blood sugar metabolism that can be seen years before the development of overt diabetes. Health-care professionals in the field of endocrinology are now routinely looking at these indicators in patients who are high risk for developing diabetes.
There is an association between the lengthening of the menstrual cycle and the risk for developing diabetes, particularly in obese women. In a national study of nurses, those who had a cycle length of greater than 40 days were twice as likely to develop diabetes then those who cycled every 26 to 31 days. The association is thought to be related to polycystic ovary syndrome (PCOS), which also is known to be associated with insulin resistance. Insulin resistance may be a precursor for type 2 diabetes.
By definition, diabetes is associated with a fasting blood sugar of greater than 126 mg/dl. There is another group that has been identified and referred to as having impaired fasting glucose or prediabetes. These people have a fasting blood sugar value of between 110-125mg/dl. The main concern with this group is that they have an increased potential to develop type 2 diabetes when compared to the normal population. The actual percent increase varies depending on ethnicity, weight, etc.; but it is significantly higher, regardless of absolute numbers. In addition, it is known that people with impaired fasting glucose also are at increased risk for heart disease and stroke.
The role of inflammation is an area of extreme interest in regard to disease development. For example, we have begun to understand the importance of inflammation and heart disease. We now know that inflammation may play an important role in the development of diabetes as well. An inflammation marker known as C-reactive protein (CRP) has been shown to be increased in women at risk for developing the metabolic syndrome, and in both men and women at risk for developing type 2 diabetes. Recent studies have shown shifts in the blood levels of a number of markers for inflammation during the progression from no disease, to prediabetes, and then to full-blown diabetes. This research highlights the importance of inflammation as part of the mechanism of diabetes development.
Other risks for the development of diabetes include endothelial dysfunction (abnormal response of the inner lining of blood vessels) and retinal artery narrowing (narrowing of the tiny blood vessels in the back of the eye).