Cognitive dysfunction in recovered depressive patients with silent cerebral infarction

In this study, we characterized cognitive functioning in patients with major depression and silent cerebral infarction (SCI), as detected by magnetic resonance imaging (MRI), after they had recovered from depression. Thirty-five patients with unipolar depression who experienced the onset of depression after the age of 50 underwent MRI and were classified as SCI(+) (n = 17) or SCI(-) (n = 18). The Wechsler Adult Intelligence Scale-Revised (WAIS-R) and the Uchida-Kraepelin psychodiagnostic test were administered after the patients had recovered from depression. In addition, the intelligence quotient (IQ) and mental speed of the patients in the two groups were compared. The total, verbal and performance IQ scores, as determined by the WAIS-R, were significantly lower in the SCI(+) group than in the SCI(-) group. The mental speed of patients in the SCI(+) group, as assessed by the Uchida-Kraepelin psychodiagnostic test, was almost half that of the SCI(-) group. Our findings provide further evidence that a comprehensive impairment of cognitive functioning, especially a severe reduction in mental speed, remains after recovery from depression in patients with major depression and SCI.