Cognitive Dysfunction in Major Depressive Disorder: Effects on Psychosocial Functioning and Implications for Treatment

While there is clearly an association between improvement in depressive symptoms and functioning, symptom improvement can also be dissociated from functional improvement and work loss.3,4 Hence there has been increasing recognition that symptomatic remission is an insufficient goal of treatment for MDD and that return to premorbid psychosocial functioning should be targeted.5 Cognitive dysfunction refers to deficits in attention, verbal and nonverbal learning, short-term and working memory, visual and auditory processing, problem solving, processing speed, and motor functioning. Numerous pharmacotherapy augmentation strategies have shown efficacy in MDD, including lithium52 and atypical APs,53 but cognitive dysfunction has not been specifically examined in these studies. [...]there is evidence that lithium is associated with adverse cognitive side effects that may negatively impact psychosocial functioning.54 Likewise, there is evidence to suggest that, in BD, atypical APs may worsen cognitive performance.55,56 Psychostimulants may be expected to have positive effects on cognition, but augmentation studies of osmotic-release oral system-methylphenidate57,58 and lisdexamfetamine59,60 in MDD have shown inconsistent results on depressive symptoms and subjective neurocognitive measures, although the latter were not always measured.