The Effectiveness of Mirtazapine in Posttraumatic Stress Disorder: Open Trial of 24-Week Continuation Treatment

Bahk, Won Myong; Pae, Chi Un; Chae, Jeong Ho; Jun, Tae Youn; Kim, Kwang Soo; Kim, Won

Abstract

OBJECTIVE
Although the number of studies are increasing in the pharmacotherapy of posttraumatic stress disorder (PTSD), few studies for the long-term effects of antidepressants on the treatment of PTSD were conducted. The aim of the present study was to investigate the effectiveness of mirtazapine during 24-week continuation treatment in patients with posttraumatic stress disorder. METHODS: Out of 15 patients participating in the previous 8 weeks study, 12 patients completed 24 weeks treatment with mirtazapine. Efficacy was evaluated at 12-week and 24-week using Impact of Event Scale-Revised (IES-R), Short PTSD Rating Interview (SPRINT), Interviewer-Administered Structured Interview for PTSD (SIP) and Montgomery Asberg Depression Rating Scale (MADRS). RESULTS: The scores on the IES-R, SPRINT, SIP and MADRS were significantly reduced by time from baseline to the end-point (F=36.1, df=4, p<0.001 ; F=106.3, df=4, p<0.001 ; F=121.1, df=4, p<0.001 ; F=198.9, df=4, p<0.001). On post hoc analysis, the scores of all 4 measures were significantly reduced at the end point since week 8. But, after Bonferroni correction, the reduced score was statistically significant in only SPRINT. The number of patients, whose scores reduced over 50% in all four scales, tended to increase from 3 at week 8 to 8 at the end point (p=0.063). No serious drug-related side effects were observed. CONCLUSION: This result suggests that the therapeutic effect of mirtazapine is maintained and may be even increased in the long-term treatment of PTSD. More studies in the pharmacotherapy of PTSD will be needed in the future.