Depression masquerading as diabetic neuropathy.

Fifty-nine patients referred for painful diabetic neuropathy of the lower extremities were evaluated for depression and response to antidepressant drug therapy in a double-blind controlled study. All patients were found to have substantial degrees of depression during psychiatric interview and by Kupfer-Detre test scores (8.1 +/- 0.6, as compared with control values of 4.0 to 4.3 +/- 0.2). Treatment with imipramine hydrochloride or amitriptyline hydrochloride resulted in complete remission of lower extremity pains in all patients in 10 +/- 2 weeks, with concomitant relief of depression and return of depression test scores to 3.8. These results suggest that the syndrome of painful diabetic neuropathy of the lower extremities represents a depressive equivalent in a large proportion of cases and that treatment with imipramine or amitriptyline is a successful mode of therapy for such persons.