A combination of glycosylated hemoglobin, impaired fasting glucose and waist circumference is effective in screening for individuals at risk for future type 2 diabetes

The diabetes mellitus of type 2 (DMT2) is a disease of the elderly with multifactorial pathogenesis, characterized by interactions of genetic variations suspect for diabetes, as well as of the longevity and aging genes. Since today it is still not possible to obtain the diagnosis with laboratory methods of clinical genetics, we tried to identify the subjects of risk of future diabetes on the basis of a combined measurement of glycemia, the glycosylated hemoglobin (HbA1c) and the waist circumference (WC). The studied population consisted of 2603 elderly subjects of 65–84 years of age, involved in the epidemiological study called ILSA (Italian Longitudinal Study on Aging). The subjects who displayed at the baseline an impaired fasting glucose (IFG) accompanied by HbA1c and WC values above the normal cut-points proved to be diabetic after a 3-year follow-up in 18.96%, while the subjects with normal fasting glucose (NFG) accompanied by normal HbA1c and WC values were found to be diabetic only in 1.34%. It means that the presence of abnormal values of these 3 parameters in the elderly does not allow the identification of the risks for future diabetes in the great majority of subjects. We conclude that the results of prospective studies may gain particular significance not only regarding the glycemia, but also the other 2 risk factors, if we wish to reach not only a predictive diagnosis of risk for diabetes, but also to prevent the chronic degenerative complications of it.