A prospective study of the relationship between some clinical parameters and complications of the patients with diabetes is considered. About 200 patients (male and female) have been examined. The patients are classified into five groups subject to the type of the diabetes. The data obtained for each patient are related to the type of the complications -macro vascular, retina pathology, neuron pathology and nephrite pathology and 12 clinical parameters.A mathematical model is build on the patients' data. A logistic regression to identify which factors are associated with the complications is performed. The software package used for statistical modeling of real data is STATISTICA 13.