Mar 19, 2009

A randomized trial of the anti-depressant effects of low- and high-frequency transcranial magnetic stimulation in treatment-resistant depression

PMID: 19105212
TITLE: A randomized trial of the anti-depressant effects of low- and high-frequency transcranial magnetic stimulation in treatment-resistant depression.
AUTHORS: Paul B Fitzgerald, Kate Hoy, Zafiris J Daskalakis, Jayashri Kulkarni
AFFILIATION: Department of Psychological Medicine, Alfred Psychiatry Research Centre, The Alfred and Monash University, Commercial Rd Melbourne, Vic., Australia.
REFERENCE: Depress Anxiety 2009 26(3):229-34
BACKGROUND: The majority of studies investigating the effectiveness of
repetitive transcranial magnetic stimulation (rTMS) as a treatment for
major depression have focused on high-frequency rTMS to the left
prefrontal cortex (HFL-rTMS). In addition, low-frequency right
prefrontal rTMS (LFR-rTMS) has also been shown to have antidepressant
properties. To date only a small number of studies have directly
compared the efficacy of these two approaches. METHODS: The aim of this
study, therefore, was to investigate further whether LFR-rTMS is as
effective as HFL-rTMS in the treatment of major depression. Twenty-seven
patients were randomized to one of two treatment arms (HFL-rTMS or LFR-
rTMS) for 3 weeks with a possible 1-week extension. Non-responders were
offered the opportunity of crossing over to the other treatment type.
Stimulation parameters for HFL-rTMS were 30 stimulation trains of 5 s
duration at 100% of the resting motor threshold (RMT); for LFR-rTMS,
stimulation was applied in four trains of 180 s duration (30 s inter-
train interval) at 110% of the RMT. Stimulation was provided 5-week days
per week. RESULTS: There were significant improvements seen from
baseline to end point irrespective of group and on all clinical outcome
measures. In addition, there was no deterioration in any of the measures
used to assess cognitive change, and significant improvements were seen
on measures of immediate verbal memory and verbal fluency. CONCLUSIONS
: HFL-rTMS and LFR-rTMS appear to be equally efficacious in treating
major depression. This study adds to the growing literature supporting
LFR-rTMS as an additional viable method of rTMS delivery in the
treatment of depression.