Major depressive depression(MDD) is an severe public mental disorders. The purpose of current study is using big data analysis based on clinical features and immunochemistry to investigate and establish an relapse predict model for patients with first episode MDD.

Major depressive depression(MDD) is an severe public mental disorders. The purpose of current study is using big data analysis based on clinical features and immunochemistry to investigate and establish an relapse predict model for patients with first episode MDD.

This study includes two steps. Step 1: Big data analysis based on the clinical features and immunochemical figures of 30000 patients with first episode MDD will be conducted to construct a relapse predict model.

Step 2: 300 patients with first episode MDD will be recruited in this step. Physicians prefer to give corresponding treatment recommendation based on the predictive factors to verify this relapse model.

Inclusion Criteria:

• Age from 18 to 65 years old;
• Han Chinese;
• Outpatient and inpatient patients;
• Patients met Diagnostic and Statistical Manual of Mental Disorders(DSM-IV-TR) criteria of bipolar I or II disorder, currently depressed, ascertained with the Mini International Neuropsychiatric Interview (MINI)
• Hamilton Depression Scale(HAM-D) total score≥17, HAM-D item 1 (depressed mood) score≥2, and Young Mania Rating Scale(YMRS) total score≤10 at baseline;
• Written informed consent was given;
• Junior high school education and above, with enough audio-visual ability to accomplish the visits;
• Normally resident in one country and had a residential address, able to follow-up.

Exclusion Criteria:

• Bipolar disorder rapid cycling or mixed episode;
• Experienced DSM-IV-TR axis I disorders in the 6 months prior to randomization;
• Severe personality disorder, metal retardation, anorexia/bulimia nervosa;
• Actively suicide ascertained by research psychiatrist or HAM-D item 3 score≥3(suicidality);
• Female patients who were pregnant, planning to be pregnant or breast feeding;
• Severe medical or neurological problems.