Antidepressant Effects of Mirtazapine in Patients with Major Depression

Lee, Hong Shick; Suh, Ho Suk; Kim, Chan Hyung; Kim, Kwang Soo; Chae, Jeong Ho; Oh, Kang Seob

Abstract

OBJECTIVES
Mirtazapine is a newly introduced antidepressant in Korea. The purpose of this study is to evaluate effectiveness and safety of mirtazapine as an antidepressant for the first time in Korean patients with major depression.
METHODS
This study is an open, non-comparative, multicenter study treated with mirtazapine for 6 weeks in patients with DSM-IV diagnosis of major depression who have 17-item HAMD score> or = 18 and who are between 18 and 65 years of age. Mirtazapine was administered 30 mg orally as an initial dose and could be increased to 45 mg from the 14th day of treatment, depending on the therapeutic responses of subjects. The clinical efficacy of mirtazapine was assessed at the baseline and at the 1st, 2nd, 4th, and 6th week of treatment. To assess the clinical efficacy of the drug, well-trained psychiatrists have evaluated subjects using 17-item HAMD and CGI on each evaluation periods. Also, for the evaluation of subjective symptoms of patients, BDI was used. Adverse experiences associated with mirtazapine were evaluated on each visit, with recordings of blood pressure, heart rate and weight. The responders were defined as patients with > or = 50% decrease from baseline in total 17-item HAMD scores and remitted patients with a total 17-item HAMD score of < or = 7.
RESULTS
Out of 79 subjects enrolled, 45 were completed this study. After 6 weeks, the score of 17-item HAMD, CGI and BDI demonstrated statistically significant decrease compared with at the baseline. This decrease was observed as early as the 1st week of mirtazapine treatment. Moreover, the meaningful reduction in each total scores of these different parameters on each evaluation period could be detected, except in case of 2-4 week and 4-6 week of BDI. The responder rate was 15.6% at the first week of mirtazapine treatment, 88.9% at the 6th week. The rate of remission was 2.2% at the first week and 60.0% at the 6th week. The most frequent adverse events during 6 weeks were somnolence(31.6%), drowsiness(19%) and weight gain(17.7%). Aside from sedation and weight gain, anticholinergic, cardiovascular and stimulating side effects are less than 10%, and no one complained about sexual dysfunction. The dropouts(34 subjects, 43%) were caused by adverse events(38.2%), insufficient compliance(35.3%) and uncooperation with the study(20.6%).
CONCLUSION
Mirtazapine has shown to have superior antidepressant effect in this study. Especially, this effect appeared from the early treatment phase, the 1st week of treatment. The most frequent adverse events reported were somnolence, drowsiness and weight gain. Anticholinergic, cardiovascular, stimulating adverse events as well as sexual dysfunction were rarely reported, and there was no clinical significant change on physical examinations. Therefore this study showed that mirtazapine is a superior and safe antidepressant in patients with major depression.