Subclinical stage of the disease precedes the clinical stage of moderate cognitive decline in Alzheimer's disease (AD). Subjective cognitive decline (SCD) — a condition in which the level of cognitive function habitual for the subject gradually begins to decrease. In 2021, researchers from the National Institute on Aging and the Alzheimer's Association (NIA-AA) clinical criteria for the diagnosis of SCD have been proposed, as well as features that increase the probability of preclinical stage AD in patients with moderate cognitive impairment have been identified. Patients should be offered a complex of examinations — questionnaires regarding the impact of memory impairment on current cognitive activity (forgetfulness, searching for things, difficulty finding words, etc.), testable self-report of cognitive dynamics, neuropsychological testing and diagnosis of pathopsychological changes such as depression and anxiety. It would appear that counselling in the form of interviews and/or testing of persons able to provide relevant information about the patient should be included in the examination of patients with complaints of memory disorders, regardless of their degree of severity. It may be necessary to conduct a survey on the patient’s daily activity, ability to self-service (score, orientation, planning, control and so on), as well as to obtain information about any memory-related changes that have become visible to others, because it is the data from the partner/relative that increase the predictive value of the diagnostic. The modern approach to the study of cognitive functions in elderly people without dementia in the long-term is certainly able to help identify people with a high risk of developing AD.