A Controlled Study of Repetitive Transcranial Magnetic Stimulation as a Treatment of Depression in the Elderly
Facundo Manes a1, Ricardo Jorge a1, Maria Morcuende a1, Toru Yamada a2, Sergio Paradiso a1andRobert G. Robinson a1 a1 Department of Psychiatry, The University of Iowa College of Medicine, Iowa City, Iowa, USA. a2 Department of Neurology, The University of Iowa College of Medicine, Iowa City, Iowa, USA.
Rapid transcranial magnetic stimulation (rTMS) applied to the left dorsal lateral frontal cortex has been shown to produce antidepressant effects. Older depressed patients, however, in one study showed a lower response rate than younger patients. The current study examined treatment response in 20 depressed, treatment-refractory patients (mean age 60.7 ± 9.8 years) given five sessions of rTMS at 20 Hz for 2 seconds over 20 trains at 80% of motor threshold or identical placebo stimulation, after patients had been withdrawn from their antidepressants. There were no significant differences in Hamilton Depression Scale scores either before or after treatment at 7 days' follow-up. There were three responders to active treatment and three to sham treatment and responders had significantly greater frontal lobe volume than nonresponders (p=.03). These findings suggest that the stimulation parameters used in this study were probably insufficient to produce treatment response and that frontal atrophy may interfere with the effectiveness of rTMS.
(Received May 10 2000) (Accepted September 22 2000)