Objective There is growing evidence showing a relation between depression, metabolic syndrome, diabetes, cardiovascular disease (1), serum lipid profile (2,3) and body weight (4), as well as the effects of some of the antidepressant medications on these various conditions and profiles.

The aim of the study is to examine the influence of antidepressant medications on the metabolic profiles (5) of patients suffering from Major Depressive Disorder (MDD).

Group of patients:

30 Patients aged 18-65, who were diagnosed with MDD according to the DSM-IV criteria.

Research Design and Methods:

Research duration will be 8 weeks. Patients meeting the inclusion criteria will be recruited after being diagnosed with MDD and having undertaken the HDRS. A follow-up HDRS will be taken at weeks 4 and 8. The psychiatric evaluation will be held by a resident in psychiatry.

The following metabolic parameters will be examined at base-line and at the end of the 8 weeks:

Weight, height, waist circumference, body mass index (BMI: (Weight in Kg/(Height in meters)2), sitting blood pressure (after 3 minutes of sitting).

Serum lipid profile (performed in Ziv hospital's chemistry lab): Low density lipoprotein cholesterol, High density Lipoprotein cholesterol, Triglycerides, Total cholesterol, Apolipoprotein level (Apo AI, Apo B, Apo E, Apo AII).

Fasting glucose and insulin blood levels, in order to evaluate insulin-release and resistance, according to the following formulas:

Insulin Resistance:

HOMA IR=Fasting glucose (mg/dL)x Fasting insulin (mmol/L)/405

Insulin Release:

HOMA-β={360xfasting insulin (mmol/L)}/{glucose(mg/dL)-63} Serum oxidative stress parameters according to the F2-Isoprostane kit will be measured.

Malonylaialdehyde (MDA) content in serum will be analyzed by the thiobarbituric acid reactive substances assay, which measures malondialdehyde equivalent (13). Conjugated dienes will be measured at 234nm (14, 15).

Inclusion Criteria:

• MDD diagnosed patients with a Hamilton Depression Rating Scale (HDRS) score of at least 18 points. Patients not treated with medications or such that had shown resistance to treatment, and were therefore assigned for drug replacement.
• Patients on stable therapy for hypertension, diabetes mellitus, hypothyroidism, dyslipidemia and / or weight lowering medications

Exclusion Criteria:

• Patients receiving antipsychotic treatment as well as patients on mood stabilizers will be excluded.
• Patients with uncontrolled diabetes mellitus, uncontrolled thyroid functioning, or uncontrolled hypertension, as well as patients who regularly consume alcohol will be excluded.
• Patients with uncontrolled malignancy are excluded as well.

30 Patients aged 18-65, who were diagnosed with MDD according to the DSM-IV criteria.