The aim of the study is to evaluate the effect of insulin therapy in patients with newly diagnosed type 1 diabetes on quantitative and qualitative changes of plasma lipoproteins, with particular emphasis on HDL metabolism, and analysis of the factors determining the effect of insulin therapy on lipid profile.The study is planned to cover a minimum of 100 people with newly diagnosed type 1 diabetes and lead prospective observation of this group (for a minimum of 5-10 years). Patients will be assessed: during the first hospitalization in the moment of diagnosis (prior to introduction of insulin treatment), after 3 weeks, after 6 months and after 12 months of insulin therapy. Further observations planned in the annual intervals. In addition, the study group will be under constant monitoring of metabolic evaluation every three months in the Outpatient Clinic.

During each follow-up will be assessed parameters evaluating the metabolism of plasma lipoprotein fractions and subfractions of HDL:

1. The concentration of apolipoprotein: including A-I, A-II, A-IV, C (II and III), D and E

2. Electrophoresis of plasma lipoproteins

3. Electrophoresis of HDL

4. The activity of enzymes: acyltransferase lecithin: cholesterol (LCAT) and plasma lipoprotein lipase Moreover, evaluation of factors which may potentially modify the relation between insulin therapy and lipoproteins will be assessed

   1. Anthropometric data and markers of insulin resistance (such as BMI, waist-hip ratio, the estimated rate of glucose distribution, VAI index, body fat, blood pressure),
   2. Metabolic management of diabetes,,
   3. Protein glycation end products
   4. The concentration of plasma adipokines.

Expected impact of the research project on the development of science, civilization and society The obtained results allow to assess the impact of exogenous insulin on quantitative and qualitative changes and metabolism of lipoproteins in the serum of patients with type 1 diabetes. Understanding the etiopathogenesis of this phenomenon and the factors affecting it seem to be very important in the treatment of patients with type 1 diabetes, where insulin is the treatment of choice and dosage adjustment appears to be extremely important. Remains unknown whether the changes in the lipoprotein profile result from the beginning of insulin therapy or other factors influence it. Selecting a group of patients with less favorable lipoprotein profile may allow better metabolic control, and thus will affect the quality and length of life of our patients. These studies will assess the impact of our therapeutic actions on the diagnosis of the disease on long-term consequences, such as the development of chronic complications.

Inclusion Criteria:

• New onset type 1 diabetes and treatment with insulin.
• Written consent to participate in the study.
• There are no other medical conditions, and with no other additional drugs beyond insulin

Exclusion Criteria:

• any other medical conditions, and any other additional drugs beyond insulin

A minimum of 100 people with newly diagnosed type 1 diabetes hospitalized in the Department of Internal Medicine and Diabetology Poznan University of Medical Sciences