The aim of the present study is to compare the efficacy of liraglutide vs. naltrexone/bupropion on metabolic and cardiovascular risk markers, weight loss, as well as the postprandial secretion of gastrointestinal hormones involved in hunger and satiety, after a test meal. The study will include 40 patients, who will further be divided into two treatment groups (20 patients on liraglutide vs. 20 patients on naltrexone/bupropion). The patients will be examined at baseline, 3 and 6 months after the treatment initiation.

This is a prospective study of patients aged ≥18 years, who are overweight (BMI ≥ 27 kg / m2 in the presence of dyslipidemia or hypertension or obstructive sleep apnea or fatty infiltration or prediabetes) or obese patients (BMI ≥ 30 kg / m2). Patients' data will be collected before starting medication (time 0) and at 3 and 6 months under treatment in the clinical practice of the selected drug, as described in the drug's package leaflet, along with a simultaneous dietary intervention and exercise. Patient groups will be comparable in age, gender and BMI.

The aim of the study is the comparison of the efficacy of liraglutide vs. naltrexone/bupropion in metabolic and cardiovascular markers.

The following parameters will be measured:

• Weight, height, waist and hip circumference
• 24-hour recording of blood pressure and heart rate
• HbA1c, total cholesterol, LDL, HDL, urine albumin/creatinine ratio
• Bioelectric impedance for determination of total and visceral fat and muscle mass Indirect calorimetry for the determination of resting metabolic rate and total energy expenditure
• Determination of baroreflex sensitivity (BRS) and heart rate variability (HRV) to investigate the function of the autonomic nervous system
• Blood sample test meal at 0, 30, 60, 90, 120, 150 and 180 min to determine insulin concentration and gastrointestinal hormones involved in hunger and satiety with modern indirect calorimetry to determine postprandial thermogenic analog scales (VAS)
• Neuropathy tests
• Assessment of quality of life with the SF-36 questionnaire and assessment of the feeling of hunger and satiety
• Echocardiographic determination of the left systolic and telodiastolic diameter of the left ventricle, cardiac fat and the Tei index at times 0 and 6 months with medication
• Pericardial fat

Inclusion Criteria:

• Age ≥18 years with BMI ≥ 30 kg / m2 or BMI ≥ 27 kg / m2 in the presence of dyslipidemia or hypertension or obstructive sleep apnea or fatty infiltration or prediabetes.

Exclusion Criteria:

1. Presence of any clinical contraindications for the administration of liraglutide or bupropion / naltrexone
2. Bariatric surgery
3. Diabetes type 2
4. Active malignancy
5. Medication that affects weight (eg corticosteroids, phenothiazines)