Reuters Health Information 2007. © 2007 Reuters Ltd.
NEW YORK (Reuters Health) Sept 19 - Lithium is more effective than phenelzine in elderly patients with treatment-resistant major depression, results of a new study suggest.
"Up to a third of elderly patients with major depressive disorder do not respond to a first course of treatment with an antidepressant," Dr. Rob M. Kok, of Altrecht Institute of Mental Health Care, Utrecht, the Netherlands, and colleagues write in the August issue of the Journal of Clinical Psychiatry.
"There is a lack of controlled studies evaluating therapies for treatment-resistant depression in late-life depression," they wrote, "and no randomized controlled studies assessing the efficacy and tolerability of lithium augmentation in elderly patients have been published."
In an open, randomized, controlled study, the researchers compared the efficacy and tolerability of lithium augmentation versus the classic monoamine oxidase inhibitor (MAOI) phenelzine in the treatment of elderly inpatients (at least 60 years of age) with major depressive disorder who had previously failed to respond to at least one treatment with a tricyclic antidepressant or venlafaxine.
A double-blind trial was not feasible, the team explains, "as the lithium serum levels had to be monitored in the lithium-treated patients, dietary restrictions were necessary for the phenelzine patients, and the antidepressant had to be continued in the lithium patients and stopped in the phenelzine patients."
After 6 weeks, 5 of the 15 patients receiving lithium augmentation but none of the 14 receiving phenelzine achieved remission, defined as a final score 10 or less on the Montgomery-Asberg Depression Rating Scale =MADRS, p = 0.042).
"On the secondary outcome measures, there was also a =tatistically significant difference between patients with lithium and phenelzine," Dr. Kok's team reports.
All but one patient experienced at least one adverse event. The mean number of adverse events was 4.3 in the lithium group and 5.7 in the phenelzine group. Adverse events were generally mild or moderate in intensity, and none of the patients were withdrawn from treatment because of adverse events.
After the 6-week trial, the patients were followed for 2 years, during which time dosages and medications were adjusted. Overall, 25 patients did eventually achieve remission.
The investigators note that they had expected both medications to be effective, and that phenelzine might be better tolerated. Instead, they conclude, "Lithium was more effective than phenelzine in elderly patients with treatment-resistant major depressive disorder, while tolerance of both treatments was remarkably good in this group of elderly inpatients with many comorbid medical disorders."
J Clin Psychiatry 2007;68:1177-1185.