Selenium as Augmentation Treatment for Sertraline Resistant Major Depression

This research aims to verify in a pilot study the effect of selenium as an augmentation treatment for sertraline-resistant major depression and, as secondary endpoints, if the levels of selenium in patients with depressive episodes are different from individuals without depression. Thus, this clinical trial was intended to be a randomized double-blind placebo-controlled clinical trial evaluating the effect of selenium or placebo in patients diagnosed with major depression who have not responded to treatment with sertraline in appropriate dose and treatment duration. The initial sample will be comprised of patients with moderate or severe major depression, who will receive sertraline up to 200mg/day, for at least 8 weeks. A group of subjects without major depression will be selected as a control sample, which will be submitted to the same procedures of the included patients. It is estimated an initial sample of 90 patients with major depression (DSM-IV criteria), and about 30 patients resistant to treatment, which will be randomly divided into two groups (selenium and placebo). The control group sample is estimated to be 45 subjects.

For the diagnosis of major depression, it will be used the Structured Clinical Interview for DSM Axis I disorders (SCID Structured Clinical Interview for the DSM-IV Axis I disorders). To evaluate the outcome of treatment of the depressive symptoms, it will be used the Clinical Global Impression Scale and Patient Global Impression Scale (CGI and PGI), Hamilton Depression Rating Scale of 17 items for depression (HAM-D-17), Montgomery-Asberg Depression Rating Scale (MADRS) and SAFTEE- (brief structured interview assessing adverse events). The exclusion criteria include patients with any diagnosis of psychosis, bipolar disorder, personality disorder, any psychiatric condition that need hospitalization, severe risk of suicide, recent drug abuse or dependence, use of any polyvitamin substance, or any substance with known relevant psychopharmacological action, women with known or suspected pregnancy or breastfeeding, and people with unstable organic disease such as lupus erythematosus, uncontrolled diabetes mellitus, hypothyroidism and hyperthyroidism.

Participation is voluntary, and participants of both genders must be over the age of 18 years. After checking for exclusion and inclusion criteria (visit 0), the first phase of the study will start with the completion of the following laboratory tests: serum levels of selenium, electrocardiogram, hematology (hemoglobin, hematocrit, white blood cell count, platelet count), SGOT, SGPT, gammaGT, urea, creatinine, fasting glucose, TSH, free T4, T3, Na, K, total cholesterol + triglycerides fractions, urine analysis.

The second phase consists in the treatment of patients with depression with sertraline, which will receive initial dosage of 50 mg / day up to 200 mg or maximum tolerated dose, according to the investigator's decision, for at least 8 weeks. Patients considered resistant-sertraline (Hamilton-D-17> 7) will be invited to participate in the double-blind randomization phase to treatment groups with placebo or selenium (400 mcg / day). Sertraline will be maintained throughout the whole phase randomization. As the trial would be completed, participants will be referred to outpatient care in community health services. Initially the variables will be analyzed descriptively. In phase 1 Student's test will be used in order to compare the serum levels of selenium in both groups. At stage 2 for comparison of pre and post treatment with Sertraline it will be used the non-parametric McNemar test and in step 3, to determine the behavior of the groups during six weeks, it will be used analysis of variance with repeated measures.