Mood disorder and multiple sclerosis.

A systematic psychiatric evaluation was performed on 100 consecutive patients attending a multiple sclerosis clinic. Forty-two percent of the patients had lifetime history of depression, and 13% fulfilled criteria for manic-depressive illness. Only 28% of the patients had no psychiatric diagnosis. The relationship of psychiatric disorder to neurologic dysfunction and other aspects of multiple sclerosis are presented. Clinical and theoretical implications of these findings are discussed.