J Neurol 2002 Jul;249(7):815-20
Feinstein A, O'Connor P, Feinstein K.
Department of Psychiatry, University of Toronto and Sunnybrook and Women's College Health Sciences Centre, Room FG38, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada.
The objectives were twofold: a) to explore a possible association between major depression and treatment with interferon beta-1b in patients with multiple sclerosis; and b) to investigate whether putative antecedent risk factors such as a previous psychiatric history and a family history of affective illness influence the prevalence of major depression post-treatment with interferon beta-1b.
Forty-two patients with relapsing-remitting MS underwent neurological examination and were interviewed with the Structured Clinical Interview for Axis 1 DSM-IV Disorders prior to starting interferon beta-1b and thereafter at 3, 6 and 12 months.
Ethical considerations dictated that patients diagnosed with major depression received anti-depressant medication.
At index assessment, 21.4 % of the sample were diagnosed with a major depression, the figures falling to 17.5 %, 11.4 % and 6.3 % at 3, 6 and 12 months respectively.
The majority of subjects with a major depression had a history of psychiatric illness prior to treatment with interferon beta-1b.
A family history of affective disorder was not associated with a significantly increased rate of major depression either before or after treatment with interferon beta-1b.
While the study's methodology did not address causality, the data demonstrate that major depression post-treatment with interferon beta-1b is linked to a history of psychiatric illness prior to starting treatment.
The threefold decline in prevalence rates for major depression over the course of a year demonstrates a good response to anti-depressant medication and possible beneficial effects of interferon beta-1b on mood.