Effect of comorbid anxiety on treatment response and relapse risk in late-life depression: controlled study.

Background: Comorbid anxiety is common in depressive disorders in both middle and late life, and it affects response to antidepressant treatment.

Aims: To examine whether anxiety symptoms predict acute and maintenance (2 years) treatment response in late-life depression.

Method: Data were drawn from a randomised double-blind study of pharmacotherapy and interpersonal psychotherapy for patients age 70 years and over with major depression. Anxiety symptoms were measured using the Brief Symptom Inventory. Survival analysis tested the effect of pre-treatment anxiety on response and recurrence.

Results: Patients with greater pretreatment anxiety took longer to respond to treatment and had higher rates of recurrence. Actuarial recurrence rates were 29% (pharmacotherapy, lower anxiety), 58% (pharmacotherapy, higher anxiety), 54% (placebo, lower anxiety) and 81% (placebo, higher anxiety).

Conclusions: Improved identification and management of anxiety in late-life depression are needed to achieve response and stabilise recovery.