Jw. Stewart et al., Atypical features and treatment response in the National Institute of Mental Health Treatment of Depression Collaborative Research Program, J CL PSYCH, 18(6), 1998, pp. 429-434
Because depression with atypical features is poorly responsive to imipramin
e, treatment trials including a tricyclic antidepressant arm should assess
depressive subtype. Sotsky and Simmens had previously reanalyzed data from
the National Institute of Mental Health Treatment of Depression Collaborati
ve Research Program (TDCRP) providing independent confirmation that imipram
ine is ineffective for patients with atypical features. The TDCRP was a 16-
week study in which 239 outpatients with major depression were randomly ass
igned to cognitive behavior therapy (CBT), interpersonal psychotherapy (IPT
), imipramine-case management (IMI-CM), or pill placebo-case management (Pb
o-Chl). We used Sotsky and Simmens' algorithm to investigate the effect of
diagnostic subtype on all four treatments. Hierarchical multiple regression
analyses demonstrated IMI-CM benefit relative to Pbo-CM in patients withou
t but not in those with atypical features. These analyses did not demonstra
te differential psychotherapy efficacy between depressive subtypes. In conc
lusion, subsequent analyses of the TDCRP study demonstrated the need to ide
ntify the subgroup of depressed patients who have atypical features. Failur
e to identify this subtype underestimates imipramine's benefit in the appro
priately treated subgroup. Comparisons of other treatments with imipramine
may be misleading if they do not account for diagnostic subtype.