A - 126 Cognitive Performance in Individuals with Major Depressive Disorder and no Diagnosis.

Abstract

To compare performance in neuropsychological assessments between a sample of individuals with Major Depressive Disorder (MDD) and those with no diagnosis. The MDD group (n = 77; Mage = 34.69, SD = 12.80; Med =13.41, SD = 2.45) had 41.6% male, 69.7% White, 10.5% Black, 17.1% Hispanic, and 2.6% other race). The undiagnosed group (n = 83, Mage = 33.39, SD = 11.82; Med =13.62, SD = 3.02) had 56.6% male, 56.6% White, 18.1% Black, 16.9% Hispanic, and 8.4% other. Participants were selected from a de-identified outpatient clinical database. The groups did not differ significantly in age, years of education, race, or gender (p values >0.05). No significant differences were found in intellectual functioning or memory ability as measured by the WAIS-IV and WMS-IV, respectively (p values >0.05). At the group level, individuals diagnosed with MDD completed significantly fewer categories [t(137) = -2.15, p = 0.02] and made more errors [t(137) = 1.99, p = 0.02] and perseverative responses [t(135) = 2.66, p = 0.004] on the WCST than undiagnosed participants. The increased number of errors and perseverative responses among individuals with MDD might be associated with difficulties sustaining attention, set-shifting, and abstract concept formation associated with depression. As expected, we did not observe differences in recognition memory or intellectual functioning, which tend to remain stable in the presence of mood disorders. Limitations of our study include the lack of a premorbid measure of intellectual functioning and MDD severity. Future research could explore the effect of MDD severity on cognitive performance.