Response to phenelzine and imipramine in placebo nonresponders with atypical depression. A new application of the crossover design
F. M. Quitkin, W. Harrison, J. W. Stewart, P. J. McGrath, E. Tricamo, K. Ocepek-Welikson, J. G. Rabkin, S. G. Wager, E. Nunes and D. F. Klein
Department of Psychiatry, Columbia University, New York, NY.
We employed a study design that permitted a double-blind 12-week contrast
of imipramine hydrochloride and phenelzine sulfate therapies in patients
who met Columbia University criteria for atypical depression and were
unresponsive to 7 weeks of treatment with placebo. These patients were
found to benefit selectively from therapy with monoamine oxidase inhibitors
compared with tricyclic drug therapy. This supports our observation about
treatment response in depressed patients with reversed vegetative features.
The design we utilized in this study has not previously been reported, to
our knowledge. It was hypothesized that it would offer the advantage of the
removal of a portion of placebo responders and serve to replicate our
original findings. Treatment response to therapy with both imipramine and
pheneizine in placebo nonresponders was uniformly lower (roughly 20% less
than corresponding rates for patients who did not participate in the
initial 6-week placebo trial). This is consistent with the view that the
lower response rates were a result of the removal of some "placebo"
responders in the drug groups. We think this is a useful design that should
be considered in all studies of placebo and two active treatment regimens.