Metformin as Adjunct Therapy in Depression-obesity Comorbidity: Clinical and Genetic Evaluation

Inclusion criteria

• Group I: Normal Controls Group II: Depression Group III: Obesity
• Group IV and V:
• Age ≥ 18 years
• Both males and females
• Recurrent depressive disorder (6A71) according to ICD-11,
• Asian cut off: Obese and overweight (BMI \< 23)
• BDI score ≥ 13 or PHQ score ≥ 4
• Either medication-naïve or medication-free for at least 2 weeks before enrollment, or the patient did not take antidepressants during the last 7 days before study entry (discontinuation of effective medication to enable study participation is prohibited)
• In case of non-psychotropic medication: The patient received stable pharmacological medication for at least 14 days before study entry (any changes in medication dose or frequency of therapy must be answered with no)

Exclusion criteria

• Groups I-III: Negative Controls (Normal: no depression and Obesity for SNP comparison only)
• Age less than 18
• Dementia/ Mentally impaired who can not fill self report performas for inclusion criteria
• Group IV: Positive Control (RCT patients)
• Patients with comorbid conditions (HTN, CKD) if taking any drug for that condition.
• The patient is not an employee of the investigator study site, or a family member of the employees or the investigator, or otherwise dependent on the sponsor, the investigator, or the investigator study site.
• The patient did not participate in other interventional trials during the 6 months before and at the time of this trial. The patient does not have a history of non-response to antidepressants included in the study.
• The patient has not given birth within the 6 months before study entry and is not breastfeeding
• The patient did not receive treatment with ketamine, irreversible MAO inhibitor (e.g. tranylcypromine), electroconvulsive therapy (ECT) or other stimulatory treatments in the index episode.
• The patient is not diagnosed with dementia and does not have moderate or severe impairment of general cognitive function according to clinical impression.
• The patient does not meet the criteria for alcohol use disorder (DSM-5: 303.90; ICD-10: F10.20) or substance use disorder (DSM-5: 304; ICD-10: F11.20 - F19.20) in DSM-5, and a urine/serum drug screening is negative (except for benzodiazepines and opiates).
• The patient does not have:
• A known allergy or contraindication against antidepressants included in the study
• History of suicidal tendencies
• Uncontrolled hepatic disorder, renal or cardiovascular disease
• Untreated hypothyroidism
• History of myocardial infarction or stroke
• Symptomatic peripheral arterial disease
• Monogenic familial hypercholesterolemia