Delusional Depression: Tricyclic Response

To the Editor.—  Howarth and Grace¹ have suggested that a number of reports indicate that tricyclic antidepressants (TCAs) might work effectively in the treatment of delusional depression, and they have cited three reports.^2-4 Our reading is that only the 1978 reanalysis by Quitkin et al² of Klein's 1959 data might suggest that delusional depressive patients respond to TCAs at a rate equal to that of nondelusional patients. The other two cited studies actually show a lower rate of response among delusional compared with nondelusional patients.The study by De Carolis et al³ is particularly striking because of the sample size (181 delusional patients with a 40% response rate vs 256 nondelusional patients with a 68% response rate; P<.001). Simpson et al⁴ clearly noted that "depressed patients who were deluded tended to have a higher failure rate than those who were not deluded." Both studies' conclusions