Neurocognitive Profiles in Affective and Amnestic Mild Cognitive Impairment

Abstract

Differentiating mild cognitive impairment due to a depressive episode from early neurodegeneration is challenging among older people. Although neuropsychological tests are routine diagnostic assessments in the evaluation of cognitive decline, in contrast to dementia syndromes, they are often perceived as non-specific in the differentiation of affective and neurodegenerative mild cognitive impairment. Furthermore, depression may represent not only a risk factor for developing dementia but also a prodromal symptom of incipient neurodegeneration. In a university memory disorder clinic setting, we investigated 90 middle-aged and older individuals (57.8% women) suffering from mild cognitive impairment, presenting with or without current or previous depressive disorder. Using discriminance analysis and a multivariate analysis of variance, we show that impairments in executive functioning and attention were predictive towards cognitive impairment developed during a depressive episode. Reduced verbal fluency was also predictive towards depression-associated cognitive impairment, whereas memory was relatively preserved in these patients. Our data suggest that in addition to biological markers, specific neuropsychological profiles can be helpful to separate different etiologies of mild cognitive impairment.