Subjective cognitive impairment as a manifestation of Alzheimer's disease or emotional disorders

Cognitive impairment (CI) is one of the most common types of neurological disorders and a frequent cause of disability. However, in 20–30% of patients who visit specialized centers (memory clinics) with cognitive complaints, no abnormalities are detected in extended neuropsychological testing. This condition is referred to as subjective cognitive impairment (SCI). According to international studies, SCI in older adults may be a predictor of clinically significant CI in the future, up to and including the development of dementia. We present our own observations of two patients with SCI who, despite subjective complaints of memory loss and a family history of Alzheimer's disease (AD), did not show any clinically significant deviations from the norm in an extended neuropsychological examination. Both patients had emotional disturbances (anxiety). The first patient with SCI had positive biological markers of AD in the cerebrospinal fluid (CSF), which allowed her condition to be classified as SCI with Alzheimer's pathological changes. In another observation, no positive biomarkers were found, which allowed SCI to be diagnosed against a background of emotional disorders (severe anxiety). A number of studies have shown that cognitive complaints in the absence of objective cognitive decline are often explained by the presence of emotional disorders (anxiety and depression). However, on the one hand, emotional disorders are the cause of SCI, and on the other hand, their presence in patients with SCI may be a reflection of cognitive decline and a consequence of an incipient degenerative process in the brain. Issues related to the management of patients with SCI based on non-pharmacological methods are discussed. In our country, nootropic agents are widely used to treat patients with CI. Data on the use of Prospekta in vascular CI are analyzed, highlighting its efficiency and safety based on the results multicenter placebo-controlled trials.

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