The goal of this study is to evaluate correlations between VOCs in the breath and venous blood glucose values in various glycaemic states in people living with Type 2 Diabetes. VOCs are measured with a gold-standard GC-IMS device and a prototype of a novel breath analyzer. Participants will be exposed to different blood glucose levels at different rates of change by administering glucose solution and insulin and by a meal challenge.

The research project aims to expand the understanding of correlations between VOCs in the breath and venous blood glucose levels in non-insulin-dependent people with Type 2 Diabetes. To better understand correlations, the subjects are exposed to hyperglycaemic, euglycaemic and hyposglcycaemic states at different rates of change by applying a hand clamp procedure, and the VOCs are compared after a standardized meal and the same excursion by applying a hand clamp procedure. Inter- and intraparticipant variability as well as the timing of changes in the VOC spectra compared to changes in the glucose values are of interest. Secondarily, the feasibility of estimating glycaemic states with a prototype of a novel breath analyzer is being investigated.

Inclusion Criteria:

• Signed written informed consent
• T2D treated with one or more oral anti-diabetic drugs (incl GLP-1 and/or GIP)
• 10 years since T2D diagnosis
• HbA1c ≤8% (HbA1c based on last measurement by treating physician but not older than 120 days)
• Willingness to undergo study procedures
• Age 45 -70 years (inclusive)

Exclusion Criteria:

• Pregnancy and/or lactation period
• Currently on chronic or occasional treatment with pulmonary drugs
• Insulin dependency
• Smoking (last cigarette within the last six months)
• BMI above 30 kg/m²
• Lp(a) above 125 nmol/l
• LDL not in the individual target range of an earlier cholesterol goal according ESC guideline 2021 (LDL based on last measurement by treating physician but not older than 30 days)
• Irregular 12-lead ECG or increased carotid plaque burden based on a three-point sonography. Both examinations are performed and evaluated according to the investigator's judgment.
• History of, or manifested, cardiovascular diseases
• Medical history of epilepsy or other neurological disease associated with seizure events
• Known sensitivity to medical grade adhesives
• Comorbidities that are suspected to alter the VOC spectra
• Participation in another investigation with an investigational drug within the 30 days preceding and during the present investigation
• Not able to understand, write or read German