Lithium augmentation of nortriptyline for subjects resistant to multiple antidepressants

Lithium augmentation, the most studied augmentation strategy for depression, has not been evaluated in patients with a history of non-response to multiple antidepressants. The objective of this study was to assess the efficacy of lithium augmentation for patients with a history of treatment resistant depression who also failed a prospective trial of nortriptyline. We enrolled 92 subjects with treatment resistant depression. Treatment resistance was defined by at least one, but no more than five, adequate trials of antidepressants during the current episode. Subjects were treated with nortriptyline (NT) for 6 weeks. Those subjects who tolerated NT for 6 weeks and whose depression did not respond (n=35) were randomized to receive either lithium (n=18) or placebo (N=17) augmentation of nortriptyline for an additional 6 weeks. Response was defined as an equal to or greater than 50% decrease in HAM-D-17 scores. After 6 weeks of double-blind augmentation, 12.5 % of subjects responded to lithium and 20.0% to placebo. Our results revealed no significant difference between lithium and placebo augmentation. While lithium augmentation seems to be useful in depression refractory to a single medication in some studies, our data suggest limited usefulness of this option for patients refractory to multiple treatments. More definitive data await the outcome of the NIMH Sequential Treatment Alternatives to Relieve Depression (STAR*D) study.