Interferon-induced depression: prevalence and management.

Interferon-induced depression ranges from 0 to 50%. Interferon schedule and a history of psychiatric illnesses are not enough to predict who will develop symptoms and who will not. To assess the prevalence of depression during interferon therapy; to test whether Minnesota Multiphasic Personality Inventory is useful in clinical practice for the early identification of patients at risk of depression; whether and how the depression can be cured. One hundred and eighty-five patients treated with interferon and ribavirin for chronic hepatitis C. Before therapy, all patients underwent a Minnesota Multiphasic Personality Inventory and a clinical examination, specifically for the identification of depressive symptoms. Thirty-one patients developed a psychiatric disorder, 11 of them requiring treatment with anti-depressant drugs. Among the 18 patients with Minnesota Multiphasic Personality Inventory positive tests, 16 developed a psychiatric disorder, 8 of them a severe disorder (sensitivity of 0.58; 0.73 for severe disorders). Among the 154 who did not develop psychiatric side effects, 152 had a negative Minnesota Multiphasic Personality Inventory (specificity: 0.99). Severe psychiatric disorders were successfully treated with anti-depressant drugs. Psychiatric side effects are easy to see during interferon therapy. A psychiatric evaluation should be considered on all patients before treatment. If depression develops, it should be treated aggressively, and selective serotonin re-uptake inhibitors are the anti-depressants of choice.