Differences in Extracellular Vesicles From Adipose Tissue of Individuals With Obesity.

From each patient, two biopsies will be taken during surgery; one from the subcutaneous and one from the visceral adipose tissue.

From each patient, two venous blood samples (citrate, LiHe and EDTA plasma) will be taken before surgery.

Before bariatric surgery, every patient will fill out questions about general health (physical activity, sedentary behavior, sleeping pattern, ...), physical condition before surgery (nausea, food intake, ...), etc.

Length and weight will be measured to calculate body mass index (BMI). Waist and hip circumference will be assessed, as well as blood pressure (both systolic and diastolic) and heart rate at rest. Body composition will be determined using a bioelectrical impedance analysis (BIA) in the hospital. Medication use and comorbidities (that are allowed within the in-/exclusion criteria) will also be derived from the patient's medical files with patient's permission.