Depressive Cognitive Disorders

Depressive cognitive disorder, previously called pseudodementia (a term introduced by Leslie Kiloh in 1961), is a cognitive impairment secondary to neuropsychiatric symptoms that mimic neurodegenerative disorders.  Cognitive impairment secondary to depression and other mental disorders is under-recognized and undertreated, and potentially reversible causes may be overlooked. Presentation is complicated by the fact that patients with neurocognitive disorders can display signs of depression, or vice versa, and there can be overlap between neurocognitive disorders and neuropsychiatric disorders. According to some authors, cognitive symptoms associated with depression often resist treatment and linger as residual symptoms. The evidence is mixed as to whether patients with depressive cognitive disorders are more likely to develop neurocognitive disorders or if they have a good prognosis.  According to the , 5th ed, text revision (DSM-5-TR), one of the diagnostic criteria for major depressive disorder is diminished ability to think, concentrate, or make decisions. Older individuals with major depressive disorder may first complain of memory difficulties, which may be mistaken for a neurocognitive disorder. Cognitive function consists of several domains, including memory, executive function, attention, and processing speed, each of which has multiple aspects. Although there are some research findings of long-term impaired cognitive functioning as a sequelae of major depressive disorder, the literature does not show clear results.  Depressive cognitive disorders may also be observed in the context of bipolar disorder mania, hypomania, or mixed episodes, although mostly occurring during depressive episodes. Symptoms include disorientation, inattention, and short-term memory deficits. Mania in older adults often has an atypical presentation compared to younger individuals, and they are often misdiagnosed with dementia.