DIABAGE (Diabetes Advanced Glycation End products) study was conducted between 2015 and 2017. It included 196 type 1 diabetic patients with more than 10 years of diabetes. It revealed a significant association between the occurrence of vascular complications and tissular Advanced Glycation End products (AGEs) as well as with some circulating AGEs. This protocol is a continuation of that initial research.

The objective is to evaluate in patients included in the DIABAGE study the incident vascular events (micro and macroangiopathic) after at least 5 years of follow-up.

The secondary objectives are:

1. To assess the predictive value of the initial measurement of AGEs (Advanced Glycation End Products) on the occurrence of these complications.
2. To study the correlation between tissue AGEs measured after 5 years of evolution and HbA1c values between the first inclusion and this new evaluation.

Material and Methods:

Experimental design: monocentric observational study (Reims University Hospital).

Population/patients: patients included in the DIABAGE study are regularly followed in the Endocrinology, Diabetology, Nutrition department of the Reims University Hospital.

Investigation plan:

• All patients in the DIABAGE study will be invited to participate. The estimated participation rate is between 80 and 90%.
• The explorations will be carried out as part of their usual follow-up during a short hospitalization (day or week hospital, depending on the patient). A careful clinical examination will be conducted, as well as a biological check-up. If necessary, investigations for chronic complications will be carried out, including a fundus, systolic pressure indexes, an electrocardiogram and, if necessary, an evaluation of the Coronary Artery Calcium score. Skin auto-fluorescence will also be measured using the AGE-Reader (available at the University Hospital).

Judgement criteria:

Primary endpoint: measurement of the incidence of micro and macro angiopathic vascular complications occurring during the follow-up of type 1 diabetic patients in the DIABAGE cohort.

Secondary endpoints:

• Measurement of initial circulating and tissue AGEs.
• Measurement of tissue AGE delta, defined as the difference between AGE after at least 5 years and baseline AGE.
• Repeat measurements of HbA1c over the follow-up period.

Inclusion Criteria:

• Inclusion in initial DIABAGE study.
• Follow-up at Reims hospital.

Exclusion Criteria:

- Refusal to participate.

• Inclusion in initial DIABAGE study.
• Follow-up at Reims hospital.