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Old Age Dementia: Clinical Patterns of Progression. Part 1

Background: the clinical experience testifies to the fact, that the increase of dementia severity in late age occurs quickly in some cases and in others it proceeds slowly, which is reflected in the total duration of the disease and survival. One of the aspects of dementias research is the study of significant differences in dementia progression rates.The objective of the review was to generalize the obtained data on progression rates of late age dementias of various genesis, first of all due to Alzheimer’s disease and its associated disorders.Material and methods: papers in MedLine/PubMed bases from1990 to 2020 were selected and analyzed according to the key words: “old age”, “dementia”, “Alzheimer’s disease”, “vascular dementia”, “progression”, “progression rate”, “disease trajectories”, as well as relevant papers in the references of the analyzed works.Conclusion: the history of research of old age dementias natural course was presented in the review of scientific publications. According to the results of development of progression rates detection methods, singling out of dementias with rapid and slow increase in the severity of cognitive decline was substantiated. Works devoted to the study of frequency and nosological belonging of dementias with different progression rates were considered. In the most recent studies prognostic models with detection of various trajectories of the course of the disease were developed. The concept of various dementias progression rates admittedly has practical meaning for provision of diagnostic and treatment assistance and planning of medical and social support measures for patients with dementia and their families. Differentiation of dementia progression clinical patterns during formation of comparable groups of patients seems appropriate for investigation of new therapy methods, as well as in clinical-biological studies of pathogenesis.