Does lorazepam impair the antidepressant response to nortriptyline and psychotherapy?

Background: This analysis sought to determine whether lorazepam influences time to response or rate of response in elderly depressed patients receiving nortriptyline and psychotherapy and to examine clinical and polysomnographic correlates of lorazepam treatment. Method: Patients with recurrent major depressive disorder (N = 119; mean +/- SD age = 68.0 +/- 6.1 years; diagnosis defined by Research Diagnostic Criteria) received acute treatment with nortriptyline and interpersonal psychotherapy. Thirty-five patients received open-label adjunctive lorazepam for anxiety or insomnia symptoms (LZ+) and 84 did not. Statistical analyses were conducted between the LZ+ group and a group of 35 patients who received no lorazepam (LZ-) and were matched for anxiety level. Patients had polysomnographic studies prior to treatment and after remission of depressive symptoms. Results: The LZ+ group reported more anxiety on the Brief Symptom Inventory (p = .04) compared with the remaining 84 patients. The LZ+ group had a greater proportion of endogenous depression subtype than the anxiety-matched LZ- group, in addition to more abnormal EEG sleep (higher percentage of REM sleep, shorter REM latency, lower delta sleep ratio). Mean time to initial antidepressant response was no different between groups. However, a significantly greater proportion of LZ+ than LZ- patients responded to acute treatment (91.4% vs. 71.4%; p < .03). Conclusion: Adjunctive lorazepam does not slow the antidepressant response to combined antidepressant/psychotherapy treatment in elderly depressed patients, and it is associated with a greater likelihood of antidepressant response. A greater percentage of patients treated with lorazepam have endogenous depression subtype and abnormal sleep findings (EEG) than those who are not treated with lorazepam. Adjunctive lorazepam is useful for treating anxiety in elderly depressed patients.