Clinical Response of Ketamine Infusions in Adolescents with Treatment-Resistant Depression

Abstract

Ketamine has recently been studied for its anti-depressant effects in adults with treatment-resistant depression (TRD). The latest data suggests that multiple infusions may have more sustained effects. However, there are no reports on the effects of ketamine in adolescent TRD. This study examined efficacy and durability of anti-depressant effects in an adolescent sample, and particularly examined what specific symptoms of depression improved the most. Participants underwent six ketamine infusions over a two-week period. The dosing was initially based on ideal weight, but changed to actual weight after five participants. The primary response measure was defined by scores of the Children’s Depression Rating Scale-Revised (CDRS-R). The Montgomery-Asberg Depression Rating Scale (MADRS) was used to track depression severity throughout the study by specific symptoms. Currently, ten participants have completed the infusions. The overall response rate is 40%. The four participants that met response criteria came from the second set of patients, for whom the dose was based on actual weight. The responders faced an extensive duration of anti-depressant effects that stretched over the six-week follow-up period (> 42 days). The average improvement seen in responders is 74%, with the strongest improvement in pessimistic thoughts, lassitude, and inability to feel. The results show that the use of ketamine in adolescents with TRD has not yielded a response rate as high as adults, but the adolescents who do benefit from ketamine tend to experience more sustained anti-depressant effects. Additionally, actual-weight dosing, versus ideal-weight dosing, may be the superior ketamine regimen.