The aim of the study is to analyse the biomechanical stiffness of red blood cells extracted from subjects with type I diabetes with and without microvascular complications through a biophysical characterization of red blood cells using microscopy, spectroscopy and scattering measurements. 48 subjects with type 1 diabetes, 24 with and 24 without microvascular complications will be enrolled. From all subjects a single blood sample will be taken to perform the analysis of red blood cells morpho-mechanical properties.

Inclusion Criteria:

• Diagnosis of type 1 diabetes for at least 10 years
• Stable metabolic control (HbA1c <7.5%) for at least 6 months
• BMI between 18.5 and 30 Kg/m^2
• Systolic blood pressure < 140 mmHg and diastolic blood pressure <90 mmHg

Exclusion Criteria:

• Blood pressure higher than 140/90 mmHg
• Unstable metabolic control (HbA1c >7.5%)
• BMI > 30 Kg/m^2 or < 18.5 Kg/m^2
• Liver failure
• Concomitant acute infections
• Uncontrolled thyroid diseases
• Pregnancy

Subjects with type I diabetes mellitus with (case group) and without (control group) microvascular complications. The two groups will be balanced for age (50-70 years), age of disease (>10 years), glycaemic control and BMI value.